View source for Fibroadenoma overview

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{{Fibroadenoma}}
{{CMG}} {{AE}} {{IO}} {{HL}}

==Overview==
Fibroadenoma of the breast is a [[benign]] [[tumor]] characterized by proliferation of both [[gland]]ular and [[Stroma (animal tissue)|stromal]] elements.
==Classification== 
Fibroadenoma may be classified according to microscopic histopathological analysis into four subtypes, which include juvenile fibroadenoma, complex fibroadenoma, myxoid fibroadenoma, and cellular fibroadenoma. 

==Pathophysiology==
Fibroadenoma is a common benign [[tumor]] of the [[breast]]. Fibroadenoma arises from [[connective tissue]] [[cell]]s, which are cells that are normally involved in the functional and mechanical support of the surrounding tissues. Fibroadenoma demonstrate [[estrogen]] and [[progesterone]] sensitivity and may grow during [[pregnancy]]. The mediator complex subunit 12 (MED12) [[gene]] is the most common gene involved in the pathogenesis of fibroadenoma. On [[gross pathology]], a rubbery, tan colored, and lobulated mass is a characteristic finding of fibroadenoma. On [[microscopic]] [[pathology]], charectersitic findings of fibroadenoma include a biphasic proliferation of both [[stromal]] and [[epithelial]] components that can be arranged in two growth patterns; a pericanalicular growth pattern and an intracanalicular growth pattern.

==Causes==
There are no known direct causes for fibroadenoma.  Common risk factors for fibroadenoma can be found [[Fibroadenoma risk factors|'''here''']].

==Differentiating Fibroadenoma from other Diseases==
Fibroadenoma must be differentiated from other diseases that cause a similar clinical presentation, such as phyllodes tumor, [[hamartoma]], and adenomyoepithelioma. 

==Epidemiology and Demographics==
Fibroadenoma is the most common breast mass among adolescent women in the United States. There are no definite data regarding the exact incidence of fibroadenoma among the US general population. Fibroadenoma commonly affects individuals younger than 30 years of age. Females are more commonly affected with fibroadenoma than males. Fibroadenoma usually affects individuals of the African American race. Caucasian individuals are less likely to develop fibroadenoma. 

==Risk Factors==
Common [[risk factors]] in the development of fibroadenoma are [[obesity]], [[estrogen replacement therapy]], and [[pregnancy|nulliparity]].

==Screening==
According to the the U.S. Preventive Service Task Force (USPSTF), there is insufficient evidence to recommend routine screening for fibroadenoma.

==Natural History, Complications and Prognosis==
Most patients with fibroadenoma are asymptomatic. If left untreated, patients with fibroadenoma may progress to develop a painless, mobile, and well-circumscribe [[breast]] lump. Fibroadenoma is a benign tumor that rarely develops any [[complications]]. Fibroadenomas commonly enlarge during [[pregnancy]] and involute after the age of [[menopause]]. The prognosis is generally excellent, and the 5-year [[survival rate]] of patients with fibroadenoma is almost equal to the normal population.
==Diagnosis==

===History and Symptoms===
The majority of patients with fibroadenoma are asymptomatic. The hallmark of fibroadenoma is the presence of a painless, firm, solitary, mobile, slowly growing [[lump]] in the [[breast]]. 

===Physical Examination===
Patients with fibroadenoma usually appear averagely built and [[well nourished]]. [[Physical examination]] of patients with fibroadenoma is usually remarkable for a painless, firm, solitary, well-circumscribed, and mobile [[breast]] mass.

===CT Scan===
CT scan may be helpful in the diagnosis of fibroadenoma. Findings on CT scan suggestive of fibroadenoma include an oval mass with well defined borders, lobulated appearance, and localized [[calcification]]. 

===MRI===
MRI may be helpful in the diagnosis of fibroadenoma. On a T1 weighted brain MRI image, fibroadenoma is characterized by a well-defined, isointense mass located at the upper-outer quadrant of the [[breast]].

===Echocardiography or Ultrasound===
Ultrasound may be helpful in the diagnosis of fibroadenoma. Findings on ultrasound suggestive of fibrodenoma include a well-circumscribed, round to ovoid, macrolobulated mass that is generally uniformly hypoechogenic.

===Other Imaging Findings===
Breast [[mammogram]] may be helpful in the [[diagnosis]] of fibroadenoma. On breast [[mammogram]], fibroadenoma is characterized by a well circumscribed, discrete, oval mass that is isodense to [[breast]] [[gland|glandular]] tissue. The mass may contain coarse, popcorn calcification.

===Other Diagnostic Studies===
The definitive diagnosis of fibroadenoma is confirmed by an ultrasound guided [[biopsy]]. Characteristic findings for fibroadenoma on microscopic histopathological analysis can be found [[Fibroadenoma pathophysiology|'''here''']].

==Treatment==
===Surgery===
The majority of cases of fibroadenoma are self-limited and only require close follow-up. The feasibility of [[surgery]] depends on the age of the patient at the time of diagnosis. [[Surgery]] is the mainstay of treatment for fibroadenoma among patients older than 35 years of age.

==References==
{{reflist|2}}

{{Soft tissue tumors and sarcomas}}

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[[Category:Breast]]
[[Category:Up-To-Date]]
[[Category:Oncology]]
[[Category:Medicine]]