Skin cancer
|
Skin cancer Microchapters |
| Skin cancer | |
| ICD-10 | C43-C44 |
|---|---|
| ICD-9 | 172, 173 |
| ICD-O: | 8010-8720 |
| MeSH | D012878 |
For patient information click here
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sara Mohsin, M.D.[2]Faizan Sheraz, M.D. [3]
Overview
Skin cancer is the malignant growth on the skin which can have many causes. Skin cancer generally develops in the epidermis (the outermost layer of skin), so a tumor is usually clearly visible. This makes most skin cancers detectable in the early stages. There are three common types of skin cancer, each of which is named after the type of skin cell from which it arises. Cancers caused by UV exposure may be prevented by avoiding exposure to sunlight or other UV sources, wearing sun-protective clothes, and using a broad-spectrum sun screen. Skin cancers are the fastest growing type of cancer in the United States. Skin cancer represents the most commonly diagnosed malignancy, surpassing lung, breast, colorectal and prostate cancer. More than 1 million Americans will be diagnosed with skin cancer in 2007.
Historical Perspective
Classification
- Skin cancer is broadly divided into melanoma and nonmelanoma types as shown in the following table:[1][2]
Pathophysiology
- Skin cancer is most closely associated with chronic inflammation of the skin
- UVA & UVB have both been implicated in causing DNA damage resulting in cancer[3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]
- Macroscopically, the tumor is often elevated, fungating, or may be ulcerated with irregular borders
- Microscopically, tumor cells destroy the basement membraneand form sheets or compact masses which invade the subjacent connective tissue (dermis)
- In well differentiated carcinomas, tumor cells are pleomorphic/atypical, but resembling normal keratinocytes from prickle layer (large, polygonal, with abundant eosinophilic (pink) cytoplasm and central nucleus)
- Their disposal tends to be similar to that of normal epidermis: immature/basal cells at the periphery, becoming more mature to the centre of the tumor masses
- Tumor cells transform into keratinized squamous cells and form round nodules with concentric, laminated layers, called "cell nests" or "epithelial/keratinous pearls"
- The surrounding stroma is reduced and contains inflammatory infiltrate (lymphocytes)
- Poorly differentiated squamous carcinomas contain more pleomorphic cells and no keratinization
Causes
Differentiating Skin cancer from other Disorders
Epidemiology & Demographics
- Skin cancer is a common condition because of the increased exposure to UV radiation (caused by increasing popularity of sun tanning/sun bathing)
- Individuals with lighter-skin are more vulnerable to get it
- One out of every three new cancers arises from skin in United States[20]
Risk factors
Common risk factors for skin cancer include:[21][22]
Screening
Natural History, Complications, and Prognosis
Diagnosis
History and Symptoms
Common sites of involvement
- Primarily involves the sun-exposed areas of skin such as:
- Can also involve the skin areas very rarely exposed to sun such as:
- Underneath fingernails or toenails
- Palm of the hand
- Sole of the foot
- Genital region
Common symptoms
- There are a variety of different skin cancer symptoms
- These include crabs or changes in the skin that do not heal, ulcers in the skin, discoloration, and changes in existing moles.
Physical Examination
- Basal cell carcinoma usually looks like a raised, smooth, pearly bump on the sun-exposed skin of the head, neck or shoulders
- Sometimes small blood vesselscan be seen within the tumor
- Crusting and bleeding in the center of the tumor frequently develops
- It is often mistaken for a sore that does not heal
- Squamous cell carcinoma is commonly a red, scaling, thickened patch on sun-exposed skin
- Ulceration and bleeding may occur
- When SCC is not treated, it may develop into a large mass
- Most melanomas are brown to black looking lesions
- Signs that might indicate a malignant melanoma include change in size, shape, color or elevation of a mole
- The appearance of a new mole during adulthood, or new pain, itching, ulceration or bleeding of an existing mole should be checked
Laboratory Tests
Biopsy
Other Diagnostic Studies
Treatment
- For low-risk disease, radiation therapy, electrotherapy, and cryotherapy (freezing the cancer off) can provide adequate control of the disease; both, however, have lower overall cure rates than surgery
- Moh's Microsurgery is a technique used to remove the cancer with the least amount of surrounding tissue and the edges are checked immediately to see if tumor is found
- This provides the opportunity to remove the least amount of tissue and provide the best cosmetically favorable results
- This is especially important for areas where excess skin is limited, such as the face
- Cure rates are equivalent to wide excision
- Special training is required to perform this technique
- In the case of disease that has spread (metastasized) further surgical or chemotherapy may be required
Prevention
Although the possibility of skin cancer can't be eliminated completely, but the risk for developing skin cancer can be significantly reduced by acting on the following preventive measures in the first place to decrease the excessive exposure to UV rays:[22][23]
| Preventive method | Details |
|---|---|
| Avoiding sunburns and suntans | |
| Wearing protective clothing | Wear the following while being in the outdoor environment: |
| Wearing SPF sunscreen | |
| Avoiding tanning beds | |
| Being aware of sun-sensitizing medications |
|
| Checking skin regularly and reporting any new or unusual skin changes to the doctor |
|
| Watching dysplastic nevi (abnormal irregular multiple moles) regularly |
|
| Reducing the exposure to ultraviolet (UV) radiation, especially during the early years of life |
|
Related Chapters
References
- ↑ "Nonmelanoma skin cancer - Symptoms and causes - Mayo Clinic".
- ↑ Linares MA, Zakaria A, Nizran P (2015). "Skin Cancer". Prim Care. 42 (4): 645–59. doi:10.1016/j.pop.2015.07.006. PMID 26612377.
- ↑ Yang Y, Yin R, Wu R, Ramirez CN, Sargsyan D, Li S; et al. (2019). "DNA methylome and transcriptome alterations and cancer prevention by triterpenoid ursolic acid in UVB-induced skin tumor in mice". Mol Carcinog. doi:10.1002/mc.23046. PMID 31237383.
- ↑ Yang Y, Wu R, Sargsyan D, Yin R, Kuo HC, Yang I; et al. (2019). "UVB drives different stages of epigenome alterations during progression of skin cancer". Cancer Lett. 449: 20–30. doi:10.1016/j.canlet.2019.02.010. PMC 6411449. PMID 30771437.
- ↑ Yang AY, Lee JH, Shu L, Zhang C, Su ZY, Lu Y; et al. (2014). "Genome-wide analysis of DNA methylation in UVB- and DMBA/TPA-induced mouse skin cancer models". Life Sci. 113 (1–2): 45–54. doi:10.1016/j.lfs.2014.07.031. PMC 5897904. PMID 25093921.
- ↑ Yi Y, Xie H, Xiao X, Wang B, Du R, Liu Y; et al. (2018). "Ultraviolet A irradiation induces senescence in human dermal fibroblasts by down-regulating DNMT1 via ZEB1". Aging (Albany NY). 10 (2): 212–228. doi:10.18632/aging.101383. PMC 5842848. PMID 29466247.
- ↑ Zhang C, Yuchi H, Sun L, Zhou X, Lin J (2017). "Human amnion-derived mesenchymal stem cells protect against UVA irradiation-induced human dermal fibroblast senescence, in vitro". Mol Med Rep. 16 (2): 2016–2022. doi:10.3892/mmr.2017.6795. PMC 5561982. PMID 28627622.
- ↑ Zhang C, Wen C, Lin J, Shen G (2015). "Protective effect of pyrroloquinoline quinine on ultraviolet A irradiation-induced human dermal fibroblast senescence in vitro proceeds via the anti-apoptotic sirtuin 1/nuclear factor-derived erythroid 2-related factor 2/heme oxygenase 1 pathway". Mol Med Rep. 12 (3): 4382–4388. doi:10.3892/mmr.2015.3990. PMID 26126510.
- ↑ Youn HJ, Kim KB, Han HS, An IS, Ahn KJ (2017). "23-Hydroxytormentic acid protects human dermal fibroblasts by attenuating UVA-induced oxidative stress". Photodermatol Photoimmunol Photomed. 33 (2): 92–100. doi:10.1111/phpp.12294. PMID 28106292.
- ↑ Yang S, Zhou B, Xu W, Xue F, Nisar MF, Bian C; et al. (2017). "Nrf2- and Bach1 May Play a Role in the Modulation of Ultraviolet A-Induced Oxidative Stress by Acetyl-11-Keto-β-Boswellic Acid in Skin Keratinocytes". Skin Pharmacol Physiol. 30 (1): 13–23. doi:10.1159/000452744. PMID 28142143.
- ↑ Hseu YC, Chou CW, Senthil Kumar KJ, Fu KT, Wang HM, Hsu LS; et al. (2012). "Ellagic acid protects human keratinocyte (HaCaT) cells against UVA-induced oxidative stress and apoptosis through the upregulation of the HO-1 and Nrf-2 antioxidant genes". Food Chem Toxicol. 50 (5): 1245–55. doi:10.1016/j.fct.2012.02.020. PMID 22386815.
- ↑ Hseu YC, Lo HW, Korivi M, Tsai YC, Tang MJ, Yang HL (2015). "Dermato-protective properties of ergothioneine through induction of Nrf2/ARE-mediated antioxidant genes in UVA-irradiated Human keratinocytes". Free Radic Biol Med. 86: 102–17. doi:10.1016/j.freeradbiomed.2015.05.026. PMID 26021820.
- ↑ Zhao P, Alam MB, Lee SH (2018). "Protection of UVB-Induced Photoaging by Fuzhuan-Brick Tea Aqueous Extract via MAPKs/Nrf2-Mediated Down-Regulation of MMP-1". Nutrients. 11 (1). doi:10.3390/nu11010060. PMC 6357030. PMID 30597920.
- ↑ Sun Z, Park SY, Hwang E, Zhang M, Seo SA, Lin P; et al. (2017). "Thymus vulgaris alleviates UVB irradiation induced skin damage via inhibition of MAPK/AP-1 and activation of Nrf2-ARE antioxidant system". J Cell Mol Med. 21 (2): 336–348. doi:10.1111/jcmm.12968. PMC 5264136. PMID 27641753.
- ↑ Sun Z, Du J, Hwang E, Yi TH (2018). "Paeonol extracted from Paeonia suffruticosa Andr. ameliorated UVB-induced skin photoaging via DLD/Nrf2/ARE and MAPK/AP-1 pathway". Phytother Res. 32 (9): 1741–1749. doi:10.1002/ptr.6100. PMID 29748977.
- ↑ Al-Matouq J, Holmes TR, Hansen LA (2019). "CDC25B and CDC25C overexpression in nonmelanoma skin cancer suppresses cell death". Mol Carcinog. doi:10.1002/mc.23075. PMID 31237025.
- ↑ Sehati N, Sadeghie N, Mansoori B, Mohammadi A, Shanehbandi D, Baradaran B (2019). "MicroRNA-330 inhibits growth and migration of melanoma A375 cells: In vitro study". J Cell Biochem. doi:10.1002/jcb.29211. PMID 31237010.
- ↑ Xiong Y, Liu L, Qiu Y, Liu L (2018). "MicroRNA-29a Inhibits Growth, Migration and Invasion of Melanoma A375 Cells in Vitro by Directly Targeting BMI1". Cell Physiol Biochem. 50 (1): 385–397. doi:10.1159/000494015. PMID 30286469.
- ↑ Mao XH, Chen M, Wang Y, Cui PG, Liu SB, Xu ZY (2017). "MicroRNA-21 regulates the ERK/NF-κB signaling pathway to affect the proliferation, migration, and apoptosis of human melanoma A375 cells by targeting SPRY1, PDCD4, and PTEN". Mol Carcinog. 56 (3): 886–894. doi:10.1002/mc.22542. PMID 27533779.
- ↑ "Common Cancer Types - National Cancer Institute".
- ↑ Ishdorj G, Beiggi S, Nugent Z, Streu E, Banerji V, Dhaliwal D; et al. (2019). "Risk factors for skin cancer and solid tumors in newly diagnosed patients with chronic lymphocytic leukemia and the impact of skin surveillance on survival". Leuk Lymphoma: 1–10. doi:10.1080/10428194.2019.1620941. PMID 31237469.
- ↑ 22.0 22.1 "Skin cancer - Symptoms and causes - Mayo Clinic".
- ↑ "Skin Cancer Prevention and Early Detection".