View source for Primary mediastinal large B-cell lymphoma

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{{SK}}: Mediastinal B-cell lymphoma; Mediastinal large B-cell lymphoma, PMBCL, Primary mediastinal B-cell lymphoma.

== Overview ==
Primary mediastinal large B-cell lymphoma (PMBCL) is a subtype of [[diffuse large B-cell lymphoma]] (DLBCL). It is also considered a distinct type of [[non-Hodgkin lymphoma]] (NHL) in the World Health Organization (WHO) classification system. It occurs in the thymus gland. The small gland in the centre of the chest behind the sternum where lymphocytes mature, multiply and become T cells. or lymph nodes in the center of the chest. On microscopic histopathological analysis, large-sized cells and alveolar fibrosis are characteristic findings of primary mediastinal large B-cell lymphoma. The incidence of primary mediastinal large B-cell lymphoma increases with age; the median age at diagnosis is 35 years. Symptoms of the primary mediastinal large B-cell lymphoma include  [[fever]], [[weight loss]], [[night sweats]], skin rash, facial swelling, cough, shortness of breath, and painless swelling in the neck, axilla, groin, thorax, or abdomen. Lymph node or mediastinal mass biopsy is diagnostic of primary mediastinal large B-cell lymphoma. The predominant therapy for primary mediastinal large B-cell lymphoma is [[chemotherapy]]. Adjunctive [[radiotherapy]], [[stem cell transplant]], and [[biological therapy]] may be required. The optimal therapy for primary mediastinal large B-cell lymphoma depends on the clinical presentation.<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref><ref name="canadiancancer">Primary mediastinal large B-cell lymphoma. Canadian Cancer Society. http://www.cancer.ca/en/cancer-information/cancer-type/non-hodgkin-lymphoma/non-hodgkin-lymphoma/types-of-nhl/primary-mediastinal-large-b-cell-lymphoma/?region=nb. Accessed on March 7, 2016 </ref>
==Classification==
There is no established system for the classification of primary mediastinal B-cell lymphoma. 

==Pathophysiology==
* Primary mediastinal large B-cell lymphoma most likely arises within the thymus.<ref name="seer.cancer.gov" /><ref name="pmid2423430">{{cite journal |vauthors=Addis BJ, Isaacson PG |title=Large cell lymphoma of the mediastinum: a B-cell tumour of probable thymic origin |journal=Histopathology |volume=10 |issue=4 |pages=379–90 |date=April 1986 |pmid=2423430 |doi= |url=}}</ref> 
* Patients present with a localized anterosuperior mediastinal mass. 
* The mass is often bulky and frequently invades adjacent structures such as lungs, pleura, or pericardium. 
* Spread to supraclavicular and cervical lymph nodes can occur. 
* Pathophysiologically,  tumor grows through constitutive STAT 6 phosphorylation and DNA-binding activity.<ref name="pmid15044251">{{cite journal |vauthors=Guiter C, Dusanter-Fourt I, Copie-Bergman C, Boulland ML, Le Gouvello S, Gaulard P, Leroy K, Castellano F |title=Constitutive STAT6 activation in primary mediastinal large B-cell lymphoma |journal=Blood |volume=104 |issue=2 |pages=543–9 |date=July 2004 |pmid=15044251 |doi=10.1182/blood-2003-10-3545 |url=}}</ref>
* STAT 6 phosphorylation activates Interleukin 4/ interleukin-13 signalling pathway. 
* Constitutive STAT6 phosphorylation and DNA-binding activity is detected is proved through immunohistochemical analysis. 
* Another proposed mechanism of autocrine pathway is amplification of JAK 2 pathway involves phosphorylation of IL-4 and IL-13. 
* The Janus kinase 2 (JAK2) is also constitutively phosphorylated in the primary mediastinal large B-cell lymphoma.
* Primary mediastinal large B-cell lymphoma is treated with JAK2 inhibitor AG490, resulted in partially decreased STAT6 phosphorylation, which suggests that JAK2 is partially involved in STAT6 activation in these cells.

===Genetics:===
Genes involved in the pathogenesis of primary mediastinal large B-cell lymphoma include:
* Comparative genomic hybridzation demonstrated gains in chromosome 9p24 and 2p15
* Genomic hybridization in chromosome X-p11.4-21
* Translocations involving the CIITA gene<ref name="pmid21368758">{{cite journal |vauthors=Steidl C, Shah SP, Woolcock BW, Rui L, Kawahara M, Farinha P, Johnson NA, Zhao Y, Telenius A, Neriah SB, McPherson A, Meissner B, Okoye UC, Diepstra A, van den Berg A, Sun M, Leung G, Jones SJ, Connors JM, Huntsman DG, Savage KJ, Rimsza LM, Horsman DE, Staudt LM, Steidl U, Marra MA, Gascoyne RD |title=MHC class II transactivator CIITA is a recurrent gene fusion partner in lymphoid cancers |journal=Nature |volume=471 |issue=7338 |pages=377–81 |date=March 2011 |pmid=21368758 |pmc=3902849 |doi=10.1038/nature09754 |url=}}</ref>
* Amplification of the REL oncogene<ref name="pmid8608249">{{cite journal |vauthors=Joos S, Otaño-Joos MI, Ziegler S, Brüderlein S, du Manoir S, Bentz M, Möller P, Lichter P |title=Primary mediastinal (thymic) B-cell lymphoma is characterized by gains of chromosomal material including 9p and amplification of the REL gene |journal=Blood |volume=87 |issue=4 |pages=1571–8 |date=February 1996 |pmid=8608249 |doi= |url=}}</ref>

* Hyperdiploid karyotypes, often with gains in the region on chromosome 9p containing the JAK2 gene and the genes encoding PD-L1 and PD-L2, ligands for the receptor PD-1<ref name="pmid24497532">{{cite journal |vauthors=Twa DD, Chan FC, Ben-Neriah S, Woolcock BW, Mottok A, Tan KL, Slack GW, Gunawardana J, Lim RS, McPherson AW, Kridel R, Telenius A, Scott DW, Savage KJ, Shah SP, Gascoyne RD, Steidl C |title=Genomic rearrangements involving programmed death ligands are recurrent in primary mediastinal large B-cell lymphoma |journal=Blood |volume=123 |issue=13 |pages=2062–5 |date=March 2014 |pmid=24497532 |doi=10.1182/blood-2013-10-535443 |url=}}</ref>

* The B cell leukemia/lymphoma 2 (BCL-2) gene and B cell leukemia 6 (BCL-6) gene rearrangements can occur.<ref name="pmid2788371">{{cite journal |vauthors=Lamarre L, Jacobson JO, Aisenberg AC, Harris NL |title=Primary large cell lymphoma of the mediastinum. A histologic and immunophenotypic study of 29 cases |journal=Am. J. Surg. Pathol. |volume=13 |issue=9 |pages=730–9 |date=September 1989 |pmid=2788371 |doi= |url=}}</ref>
* Gains of the proto-oncogene BCL11A and nuclear accumulation of BCL11A(XL) protein.<ref name="pmid16871282">{{cite journal |vauthors=Weniger MA, Pulford K, Gesk S, Ehrlich S, Banham AH, Lyne L, Martin-Subero JI, Siebert R, Dyer MJ, Möller P, Barth TF |title=Gains of the proto-oncogene BCL11A and nuclear accumulation of BCL11A(XL) protein are frequent in primary mediastinal B-cell lymphoma |journal=Leukemia |volume=20 |issue=10 |pages=1880–2 |date=October 2006 |pmid=16871282 |doi=10.1038/sj.leu.2404324 |url=}}</ref>

* Immunoglobulin genes clonally rearranged. 

===Immunophenotype:===
* The immunophenotype of PMBL is determined by histochemistry or flow cytometry.
* The tumor cells express B cell-associated antigens (CD19, CD20, CD22, CD79a) and CD45.<ref name="pmid2788371">{{cite journal |vauthors=Lamarre L, Jacobson JO, Aisenberg AC, Harris NL |title=Primary large cell lymphoma of the mediastinum. A histologic and immunophenotypic study of 29 cases |journal=Am. J. Surg. Pathol. |volume=13 |issue=9 |pages=730–9 |date=September 1989 |pmid=2788371 |doi= |url=}}</ref>
* Weak expression of CD30 is often present
* The tumor cells also stain for TRAF-1 and nuclear c-Rel. These two markers are also expressed by the Reed-Sternberg cells, but are not present in other forms of diffuse large B cell lymphoma. <ref name="pmid15644776">{{cite journal |vauthors=Rodig SJ, Savage KJ, Nguyen V, Pinkus GS, Shipp MA, Aster JC, Kutok JL |title=TRAF1 expression and c-Rel activation are useful adjuncts in distinguishing classical Hodgkin lymphoma from a subset of morphologically or immunophenotypically similar lymphomas |journal=Am. J. Surg. Pathol. |volume=29 |issue=2 |pages=196–203 |date=February 2005 |pmid=15644776 |doi= |url=}}</ref>
* Other markers that are relatively specific for PMBL are CD200 and MAL.<ref name="pmid22899296">{{cite journal |vauthors=Dorfman DM, Shahsafaei A, Alonso MA |title=Utility of CD200 immunostaining in the diagnosis of primary mediastinal large B cell lymphoma: comparison with MAL, CD23, and other markers |journal=Mod. Pathol. |volume=25 |issue=12 |pages=1637–43 |date=December 2012 |pmid=22899296 |doi=10.1038/modpathol.2012.129 |url=}}</ref><ref name="pmid12429796">{{cite journal |vauthors=Copie-Bergman C, Plonquet A, Alonso MA, Boulland ML, Marquet J, Divine M, Möller P, Leroy K, Gaulard P |title=MAL expression in lymphoid cells: further evidence for MAL as a distinct molecular marker of primary mediastinal large B-cell lymphomas |journal=Mod. Pathol. |volume=15 |issue=11 |pages=1172–80 |date=November 2002 |pmid=12429796 |doi=10.1097/01.MP.0000032534.81894.B3 |url=}}</ref>
===Microscopic Pathology:===
* On microscopic histopathological analysis, large-sized cells and alveolar fibrosis are characteristic findings of primary mediastinal large B-cell lymphoma.
* The tumor is composed of large cells with variable nuclear features, cells may resemble:<ref name="pmid16129841">{{cite journal |vauthors=De Paepe P, Achten R, Verhoef G, Wlodarska I, Stul M, Vanhentenrijk V, Praet M, De Wolf-Peeters C |title=Large cleaved and immunoblastic lymphoma may represent two distinct clinicopathologic entities within the group of diffuse large B-cell lymphomas |journal=J. Clin. Oncol. |volume=23 |issue=28 |pages=7060–8 |date=October 2005 |pmid=16129841 |doi=10.1200/JCO.2005.15.503 |url=}}</ref>
** Centroblasts
** Large centrocytes
** Multilobated cells, often with pale or "clear" cytoplasm 
** Less frequently, the tumor cells resemble immunoblasts
** Reed-Sternberg-like cells 
** Some cases have also presented with fine, compartmentalizing sclerosis
<gallery widths="200px"> 
Image:Primary mediastinal large B-cell lymphoma pathology .jpg|Hematoxylin and eosin (50X). Primary mediastinal B cells (PMBC) associated with delicate interstitial fibrosis.<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
Image:Primary medistinal large b-cell lymphoma pathology 1 .jpg| Primary mediastinal large B-cell lymphoma immunoreactivity for B cell antigen on the membrane, CD20<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
Image:Primary mediastinal large B-cell lymphoma pathology 2.jpg|Primary mediastinal large B-cell lymphoma immunoreactivity for CD30<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
</gallery>

==Causes==
There are no established causes of primary mediastinal  B-cell lymphoma. 

==Differentiating ((Page name)) from Other Diseases==
[Disease name] must be differentiated from other diseases that cause [clinical feature 1], [clinical feature 2], and [clinical feature 3], such as [differential dx1], [differential dx2], and [differential dx3].

OR

[Disease name] must be differentiated from [[differential dx1], [differential dx2], and [differential dx3].

==Epidemiology and Demographics==
Primary mediastinal large B-cell lymphoma comprises of 7% of overall diffuse [[Diffuse large B cell lymphoma|large B cell lymphoma]]'s and 2.4 % of all [[Non-Hodgkin lymphoma|Non hodgkin lymphoma]]<nowiki/>s. <ref name="pmid9166827">{{cite journal |vauthors= |title=A clinical evaluation of the International Lymphoma Study Group classification of non-Hodgkin's lymphoma. The Non-Hodgkin's Lymphoma Classification Project |journal=Blood |volume=89 |issue=11 |pages=3909–18 |date=June 1997 |pmid=9166827 |doi= |url=}}</ref>

=== Age: ===
The incidence of [[primary mediastinal large B-cell lymphoma]] increases with age; the median age at diagnosis is 35 years.<ref name="pmid10889382" />

=== Gender: ===
Females are more commonly affected with primary mediastinal large B-cell lymphoma than males.<ref name="pmid10889382">{{cite journal |vauthors=Nguyen LN, Ha CS, Hess M, Romaguera JE, Manning JT, Cabanillas F, Cox JD |title=The outcome of combined-modality treatments for stage I and II primary large B-cell lymphoma of the mediastinum |journal=Int. J. Radiat. Oncol. Biol. Phys. |volume=47 |issue=5 |pages=1281–5 |date=July 2000 |pmid=10889382 |doi= |url=}}</ref>

==Risk Factors==
There are no established risk factors for [disease name].

OR

The most potent risk factor in the development of [disease name] is [risk factor 1]. Other risk factors include [risk factor 2], [risk factor 3], and [risk factor 4].

OR

Common risk factors in the development of [disease name] include [risk factor 1], [risk factor 2], [risk factor 3], and [risk factor 4].

OR

Common risk factors in the development of [disease name] may be occupational, environmental, genetic, and viral.

==Screening==
There is insufficient evidence to recommend routine screening for [disease/malignancy].

OR

According to the [guideline name], screening for [disease name] is not recommended.

OR

According to the [guideline name], screening for [disease name] by [test 1] is recommended every [duration] among patients with [condition 1], [condition 2], and [condition 3].

==Natural History, Complications, and Prognosis==
If left untreated, [#]% of patients with [disease name] may progress to develop [manifestation 1], [manifestation 2], and [manifestation 3].

OR

Common complications of [disease name] include [complication 1], [complication 2], and [complication 3].

OR

Prognosis is generally excellent/good/poor, and the 1/5/10-year mortality/survival rate of patients with [disease name] is approximately [#]%.

==Diagnosis==
===Diagnostic Study of Choice===
The diagnosis of [disease name] is made when at least [number] of the following [number] diagnostic criteria are met: [criterion 1], [criterion 2], [criterion 3], and [criterion 4].

OR

The diagnosis of [disease name] is based on the [criteria name] criteria, which include [criterion 1], [criterion 2], and [criterion 3].

OR

The diagnosis of [disease name] is based on the [definition name] definition, which includes [criterion 1], [criterion 2], and [criterion 3].

OR

There are no established criteria for the diagnosis of [disease name].

===History and Symptoms===
The majority of patients with [disease name] are asymptomatic.

OR

The hallmark of [disease name] is [finding]. A positive history of [finding 1] and [finding 2] is suggestive of [disease name]. The most common symptoms of [disease name] include [symptom 1], [symptom 2], and [symptom 3]. Common symptoms of [disease] include [symptom 1], [symptom 2], and [symptom 3]. Less common symptoms of [disease name] include [symptom 1], [symptom 2], and [symptom 3].

===Physical Examination===
Patients with [disease name] usually appear [general appearance]. Physical examination of patients with [disease name] is usually remarkable for [finding 1], [finding 2], and [finding 3].

OR

Common physical examination findings of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

The presence of [finding(s)] on physical examination is diagnostic of [disease name].

OR

The presence of [finding(s)] on physical examination is highly suggestive of [disease name].

===Laboratory Findings===
An elevated/reduced concentration of serum/blood/urinary/CSF/other [lab test] is diagnostic of [disease name].

OR

Laboratory findings consistent with the diagnosis of [disease name] include [abnormal test 1], [abnormal test 2], and [abnormal test 3].

OR

[Test] is usually normal among patients with [disease name].

OR

Some patients with [disease name] may have elevated/reduced concentration of [test], which is usually suggestive of [progression/complication].

OR

There are no diagnostic laboratory findings associated with [disease name].

===Electrocardiogram===
There are no ECG findings associated with [disease name].

OR

An ECG may be helpful in the diagnosis of [disease name]. Findings on an ECG suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

===X-ray===
There are no x-ray findings associated with [disease name].

OR

An x-ray may be helpful in the diagnosis of [disease name]. Findings on an x-ray suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

There are no x-ray findings associated with [disease name]. However, an x-ray may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].

===Echocardiography or Ultrasound===
There are no echocardiography/ultrasound  findings associated with [disease name].

OR

Echocardiography/ultrasound  may be helpful in the diagnosis of [disease name]. Findings on an echocardiography/ultrasound suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

There are no echocardiography/ultrasound  findings associated with [disease name]. However, an echocardiography/ultrasound  may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].

===CT scan===
There are no CT scan findings associated with [disease name].

OR

[Location] CT scan may be helpful in the diagnosis of [disease name]. Findings on CT scan suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

There are no CT scan findings associated with [disease name]. However, a CT scan may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].

===MRI===
There are no MRI findings associated with [disease name].

OR

[Location] MRI may be helpful in the diagnosis of [disease name]. Findings on MRI suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

There are no MRI findings associated with [disease name]. However, a MRI may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].

===Other Imaging Findings===
There are no other imaging findings associated with [disease name].

OR

[Imaging modality] may be helpful in the diagnosis of [disease name]. Findings on an [imaging modality] suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

===Other Diagnostic Studies===
There are no other diagnostic studies associated with [disease name].

OR

[Diagnostic study] may be helpful in the diagnosis of [disease name]. Findings suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].

OR

Other diagnostic studies for [disease name] include [diagnostic study 1], which demonstrates [finding 1], [finding 2], and [finding 3], and [diagnostic study 2], which demonstrates [finding 1], [finding 2], and [finding 3].

==Treatment==
===Medical Therapy===
There is no treatment for [disease name]; the mainstay of therapy is supportive care.

OR

Supportive therapy for [disease name] includes [therapy 1], [therapy 2], and [therapy 3].

OR

The majority of cases of [disease name] are self-limited and require only supportive care.

OR

[Disease name] is a medical emergency and requires prompt treatment.

OR

The mainstay of treatment for [disease name] is [therapy].

OR
 
The optimal therapy for [malignancy name] depends on the stage at diagnosis.

OR

[Therapy] is recommended among all patients who develop [disease name].

OR

Pharmacologic medical therapy is recommended among patients with [disease subclass 1], [disease subclass 2], and [disease subclass 3].

OR

Pharmacologic medical therapies for [disease name] include (either) [therapy 1], [therapy 2], and/or [therapy 3].

OR

Empiric therapy for [disease name] depends on [disease factor 1] and [disease factor 2].

OR

Patients with [disease subclass 1] are treated with [therapy 1], whereas patients with [disease subclass 2] are treated with [therapy 2].

===Surgery===
Surgical intervention is not recommended for the management of [disease name].

OR

Surgery is not the first-line treatment option for patients with [disease name]. Surgery is usually reserved for patients with either [indication 1], [indication 2], and [indication 3]

OR

The mainstay of treatment for [disease name] is medical therapy. Surgery is usually reserved for patients with either [indication 1], [indication 2], and/or [indication 3].

OR

The feasibility of surgery depends on the stage of [malignancy] at diagnosis.

OR

Surgery is the mainstay of treatment for [disease or malignancy].

===Primary Prevention===
There are no established measures for the primary prevention of [disease name].

OR

There are no available vaccines against [disease name].

OR

Effective measures for the primary prevention of [disease name] include [measure1], [measure2], and [measure3].

OR

[Vaccine name] vaccine is recommended for [patient population] to prevent [disease name]. Other primary prevention strategies include [strategy 1], [strategy 2], and [strategy 3].

===Secondary Prevention===
There are no established measures for the secondary prevention of [disease name].

OR

Effective measures for the secondary prevention of [disease name] include [strategy 1], [strategy 2], and [strategy 3].

<gallery widths="200px"> 
Image:Primary mediastinal large B-cell lymphoma pathology .jpg|Hematoxylin and eosin (50X). Primary mediastinal B cells (PMBC) associated with delicate interstitial fibrosis.<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
Image:Primary medistinal large b-cell lymphoma pathology 1 .jpg| Primary mediastinal large B-cell lymphoma immunoreactivity for B cell antigen on the membrane, CD20<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
Image:Primary mediastinal large B-cell lymphoma pathology 2.jpg|Primary mediastinal large B-cell lymphoma immunoreactivity for CD30<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crihem/2012/197347/. Accessed on March 07, 2016 </ref>
</gallery>

==Causes==
There are no established causes for primary mediastinal large B-cell lymphoma.
==Differentiating type page name here from other Diseases==
Primary mediastinal large B-cell lymphoma must be differentiated from other diseases such as:
* [[Thymoma]]
* [[Hodgkin's lymphoma]]
* [[Thymic carcinoma]]
==Epidemiology and Demographics==
===Age===
The incidence of primary mediastinal large B-cell lymphoma increases with age; the median age at diagnosis is 35 years.<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref>
===Gender===
Females are more commonly affected with primary mediastinal large B-cell lymphoma than males.<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref>
== Risk Factors ==
There are no established risk factors for primary mediastinal large B-cell lymphoma.
== Screening ==
According to the the U.S. Preventive Service Task Force (USPSTF), there is insufficient evidence to recommend routine screening for primary mediastinal large B-cell lymphoma.<ref name="uspreventive">Recommendations. U.S Preventive Services Task Force. http://www.uspreventiveservicestaskforce.org/BrowseRec/Search?s=Primary+mediastinal+large+B-cell+lymphoma+.  Accessed on March 7, 2016</ref>
== Natural History, Complications and Prognosis==
* Primary mediastinal large B-cell lymphoma is usually a fast-growing (aggressive) lymphoma. 
* Patients often have localized disease in the chest at first. 
* If left untreated, primary mediastinal large B-cell lymphoma can cause shortness of breath, cough, or chest pain as the mass grows in the chest. 
* Primary mediastinal large B-cell lymphoma can also partially block the main vein ([[superior vena cava]]) that carries blood from the upper body to the heart and cause [[superior vena cava syndrome]]. 
* The bone marrow is rarely affected by this type of lymphoma.
* Recurrence or relapse often occurs in organs or tissues outside the lymph nodes (extranodal sites), such as the [[kidneys]] or [[central nervous system]].

== Diagnosis == 
===Staging===
Staging for primary mediastinal large B-cell lymphoma is provided in the following table:<ref>{{Cite journal| doi = 10.1200/JCO.2013.54.8800| issn = 1527-7755| volume = 32| issue = 27| pages = 3059–3068| last1 = Cheson| first1 = Bruce D.| last2 = Fisher| first2 = Richard I.| last3 = Barrington| first3 = Sally F.| last4 = Cavalli| first4 = Franco| last5 = Schwartz| first5 = Lawrence H.| last6 = Zucca| first6 = Emanuele| last7 = Lister| first7 = T. Andrew| last8 = Alliance, Australasian Leukaemia and Lymphoma Group| last9 = Eastern Cooperative Oncology Group| last10 = European Mantle Cell Lymphoma Consortium| last11 = Italian Lymphoma Foundation| last12 = European Organisation for Research| last13 = Treatment of Cancer/Dutch Hemato-Oncology Group| last14 = Grupo Español de Médula Ósea| last15 = German High-Grade Lymphoma Study Group| last16 = German Hodgkin's Study Group| last17 = Japanese Lymphorra Study Group| last18 = Lymphoma Study Association| last19 = NCIC Clinical Trials Group| last20 = Nordic Lymphoma Study Group| last21 = Southwest Oncology Group| last22 = United Kingdom National Cancer Research Institute| title = Recommendations for initial evaluation, staging, and response assessment of Hodgkin and non-Hodgkin lymphoma: the Lugano classification| journal = Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology| date = 2014-09-20| pmid = 25113753}}</ref>

{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ '''Revised staging system for primary nodal lymphomas (Lugano classification)'''
! style="background: #4479BA; color:#FFF;" | Stage
! style="background: #4479BA; color:#FFF;" | Involvement
! style="background: #4479BA; color:#FFF;" | Extranodal (E) status
|-
| colspan="3" style="padding: 5px 5px; background: #DCDCDC;" | '''Limited'''
|-
| style="padding: 5px 5px; background: #F5F5F5;" | Stage I
| style="padding: 5px 5px; background: #F5F5F5;" | One node or a group of adjacent nodes
| style="padding: 5px 5px; background: #F5F5F5;" | Single extranodal lesions without nodal involvement
|-
| style="padding: 5px 5px; background: #F5F5F5;" | Stage II
| style="padding: 5px 5px; background: #F5F5F5;" | Two or more nodal groups on the same side of the diaphragm
| style="padding: 5px 5px; background: #F5F5F5;" | Stage I or II by nodal extent with limited contiguous extranodal involvement
|-
| style="padding: 5px 5px; background: #F5F5F5;" | Stage II bulky
| style="padding: 5px 5px; background: #F5F5F5;" | II as above with "bulky" disease
| style="padding: 5px 5px; background: #F5F5F5;" | Not applicable
|-
| colspan="3" style="padding: 5px 5px; background: #DCDCDC;" | '''Advanced'''
|-
| style="padding: 5px 5px; background: #F5F5F5;" | Stage III
| style="padding: 5px 5px; background: #F5F5F5;" | Nodes on both sides of the diaphragm; nodes above the diaphragm with spleen involvement
| style="padding: 5px 5px; background: #F5F5F5;" | Not applicable
|-
| style="padding: 5px 5px; background: #F5F5F5;" | Stage IV
| style="padding: 5px 5px; background: #F5F5F5;" | Additional noncontiguous extralymphatic involvement
| style="padding: 5px 5px; background: #F5F5F5;" | Not applicable
|}

=== Symptoms ===
Symptoms of the primary mediastinal large B-cell lymphoma include:<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref>
* [[Fever]]
* [[Weight loss]]
* [[Night sweats]]
* Skin rash
* Shortness of breath
* Facial swelling
* Cough
* Painless swelling in the neck, axilla, groin, thorax, and abdomen

=== Physical Examination<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref> ===
====Vitals====
* [[Fever]] is often present 
====Skin====
* [[Rash]] 
====HEENT====
* [[Lymphadenopathy|Cervical lymphadenopathy]]
* Facial edema
====Thorax====
* Thoracic masses suggestive of [[Lymphadenopathy|central lymphadenopathy]]
* Localized anterosuperior mediastinal mass
====Abdomen====
* [[Abdominal mass]]es suggestive of [[Lymphadenopathy|central lymphadenopathy]]
====Extremities====
* [[Lymphadenopathy|Peripheral lymphadenopathy]]

===Laboratory Findings === 
Laboratory tests for primary mediastinal large B-cell lymphoma include:<ref name="seer.cancer.gov">Primary mediastinal large B-cell lymphoma. Surveillance, Epidemiology, and End Results Program. http://seer.cancer.gov/seertools/hemelymph/51f6cf56e3e27c3994bd5318/. Accessed on March 7, 2016 </ref>
* [[Complete blood count]] (CBC)
* Blood chemistry studies
* Cytogenetic analysis
* [[Flow cytometry]]
* [[Immunohistochemistry]]
* [[Immunophenotyping]]: 
:*  Positive: [[CD19]], [[CD79a]], [[CD20]], [[CD30]], and  [[CD22]] 
====Chest X-Ray====
Chest X-ray may be helpful in the diagnosis of primary mediastinal large B-cell lymphoma. Finding on chest X-ray suggestive of primary mediastinal large B-cell lymphoma includes large anterior mediastinal mass.<ref name="hindawi">Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crionm/2013/814291/. Accessed on March 07, 2016 </ref>
====Biopsy====
Lymph node or mediastinal mass biopsy is diagnostic of primary mediastinal large B-cell lymphoma.
====Echocardiography====
Echocardiography may be helpful in the diagnosis of primary mediastinal large B-cell lymphoma.
<gallery widths="200px"> 
Image:Primary mediastinal large B-cell lymphoma echo.jpg|A comprehensive 2 dimensional M-mode color flow and Doppler echocardiography reveals a normal left ventricular systolic function (EF 60–69%). A large right atrial mass measuring  cm almost fills the right atrium and extends into the tricuspid valve causing tricuspid regurgitation.<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crionm/2013/814291/. Accessed on March 07, 2016 </ref>
</gallery>

====CT ====
[[CT]] scan may be helpful in the diagnosis of primary mediastinal large B-cell lymphoma.
<gallery widths="200px">
Image:Primary mediastinal large B-cell lymphoma CT scan 1 .jpg|CT scan of the chest with contrast reveals a large lobulated anterior mediastinal solid mass (black arrow) with extension into the right hemithorax and the right atrium. There is displacement of the great vessels into the left hemithorax with significant mass effect on the right upper lobe. The tumor causes compression of the right pulmonary artery (red arrow) and right and left mainstem bronchi (white arrows).<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crionm/2013/814291/. Accessed on March 07, 2016 </ref>
Image:Primary mediatinsl large B-cell lymphoma coronal CT scan.jpg|Coronal CT scan image elucidates a mediastinal mass with extension into the right atrium (black arrow) with complete encasement and compression of the SVC. The tumor extends to the confluence of the IVC in the right atrium causing dilatation of the intraabdominal IVC and hepatic veins suggesting compromised cardiac return (red arrows). Tumor causes the displacement of great vessels into the left hemithorax.<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crionm/2013/814291/. Accessed on March 07, 2016 </ref>
</gallery>
==== MRI ====
[[MRI]] scan may be helpful in the diagnosis of primary mediastinal large B-cell lymphoma.
<gallery widths="200px"> 
Image:Primary medistinal large B-cell lymphoma MRI .jpg| Cardiac MRI short axis T1 at the level of mitral valve reveals a large mediastinal mass infiltrating and obliterating the SVC causing SVC obstruction. The tumor extends into the right atrium (red arrow) and invades the tricuspid valve.<ref name=hindawi>Primary mediastinal large B-cell lymphoma.Hindawi Publishing Corporation. http://www.hindawi.com/journals/crionm/2013/814291/. Accessed on March 07, 2016 </ref>
</gallery>
==== Other Imaging Findings ====
[[PET]] scan may be helpful in the diagnosis of primary mediastinal large B-cell lymphoma.

==Treatment==
===Medical Therapy===

{| style="border: 0px; font-size: 90%; margin: 3px;" align="center"
|+ '''Treatment of primary mediastinal large B-cell lymphoma<ref name="canadiancancer">Primary mediastinal large B-cell lymphoma. Canadian Cancer Society. http://www.cancer.ca/en/cancer-information/cancer-type/non-hodgkin-lymphoma/non-hodgkin-lymphoma/types-of-nhl/primary-mediastinal-large-b-cell-lymphoma/?region=nb. Accessed on March 7, 2016 </ref>'''
! style="background: #4479BA; color:#FFF;" | Therapy 
! style="background: #4479BA; color:#FFF;" | Description 
|-
|-
| style="padding: 5px 5px; background: #DCDCDC;" | [[Chemotherapy]]
| style="padding: 5px 5px; background: #F5F5F5;" | 
* A commonly used combination chemotherapy is CHOP: [[Cyclophosphamide]], [[Doxorubicin]], [[Vincristine]], {{and}} [[Prednisone]]
|-
| style="padding: 5px 5px; background: #DCDCDC;" | [[Biological therapy]]
| style="padding: 5px 5px; background: #F5F5F5;" | 
* [[Rituximab]] may be added to chemotherapy. 
|-
| style="padding: 5px 5px; background: #DCDCDC;" | [[Radiation therapy]]
| style="padding: 5px 5px; background: #F5F5F5;" | 
* [[External beam radiation therapy]] to the mass in the chest may be used after chemotherapy.
|-
| style="padding: 5px 5px; background: #DCDCDC;" | [[Stem cell transplant]]
| style="padding: 5px 5px; background: #F5F5F5;" |
* A [[stem cell transplant]] may be offered to some people  if their lymphoma returns or relapses after treatment.
|}

==References==
{{Reflist|2}}

[[Category:Disease]]
[[Category:Oncology]]
 [[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]
[[Category:Hematology]]
[[Category:Immunology]]