Carcinoma of the penis
Penile cancer is a malignant growth found on the skin or in the tissues of the penis. A Squamous cell carcinoma usually originating in the glans or foreskin is by far the most common type, occurring in 9 out of 10 cases.[1] Penis cancer tends to develop in men over the age of sixty. Penile cancer is very rare in Europe and North America, occurring in about one in 100,000 men in the latter. It accounts for 0.2% of cancers and 0.1% of deaths from cancer amongst males in the United States. However, in some parts of Africa and South America it accounts for up to 10% of cancers in men.[2]
Symptoms
Symptoms include redness, irritation, a sore on the penis or a lump on the penis. Anyone with these symptoms should consult a doctor immediately.[3]
Pathology
- A. Precancerous Dermatologic Lesions
- B. Carcinoma in Situ (Bowen Disease, Erythroplasia of Queyrat)
- C. Invasive Carcinoma of the Penis
Staging
Like many malignancies, penile cancer can spread to other parts of the body. It is usually a primary malignancy, the initial place from which a cancer spreads in the body. Much less often it is a secondary malignancy, one in which the cancer has spread to the penis from elsewhere. Doctors use the extent of metastasis to estimate what stage the disease is in, to aid in treatment decisions and prognosis. The stages are assessed as follows(Jackson's staging):
- Stage I - Cancer has only affected the glans and/or foreskin.
- Stage II - Cancer has spread to the shaft of the penis.
- Stage III - Mobile (operable) inguinal lymph nodes
- Stage IV - Fixed (inoperable) inguinal lymph nodes or distant metastasis.
- Recurrent - Cancer that has returned after treatment.
Prognosis can range considerably for patients, depending where on the scale they have been staged. Generally speaking, the earlier the cancer is diagnosed, the better the prognosis. The overall 5-year survival rate for all stages of penile cancer is about 50%.
Treatment
There are several treatment options for penile cancer, depending on staging. They include surgery, radiation therapy, chemotherapy, and biological therapy. The most common treatment is one of five types of surgery:
- Wide local excision - The tumor and some surrounding healthy tissue are removed
- Microsurgery - Surgery performed with a microscope is used to remove the tumor and as little healthy tissue as possible
- Laser surgery - laser light is used to burn or cut away cancerous cells
- Circumcision - cancerous foreskin is removed
- Amputation (penectomy) - a partial or total removal of the penis, and possibly the associated lymph nodes.
Radiation therapy is usually used adjuvantly with surgery to reduce the risk of recurrence. With earlier stages of penile cancer, a combination of topical chemotherapy and less invasive surgery may be used. More advanced stages of penile cancer usually require a combination of surgery, radiation and chemotherapy. In addition to all the above, treatment of the underlying disease like Brucellosis, is important to limit disease recurrence.
Risk factors
The exact cause of penile cancer is unknown. The American Cancer Society provides the following as risk factors for penile cancer:[4] human papillomavirus (HPV) infection, smoking, smegma and phimosis (both found only in uncircumcised men), treatment of psoriasis with UV light, age, and AIDS. The other etiologic factor most commonly associated with penile carcinoma is poor hygiene. There is some evidence that lichen sclerosus (also known as balanitis xerotica obliterans) may also be a risk factor.[5]
Circumcision
Most cases of penile cancer occur in countries where men are uncircumcised. There has been some debate over whether circumcision is a form of prevention.
One study reported a lifetime risk of a man in the United States developing invasive penile cancer (IPC) to be 1 in 600 if he is uncircumcised.[6] though this study has been criticised.[7] Several studies report that the risk is higher if a male was not circumcised neonatally, with relative risk estimates including 3.2[8] and 22[9] associated with the presence of a foreskin, and 0.41 associated with its absence.[10] Several authors also state that there is a lower incidence of penile cancer in circumcised men.[11][11][12][13][14] A few studies suggested that circumcision decreased the risk of HPV infection in males.[15][16][17] A study that concluded circumcision did not prevent penile cancer was done by Wallerstein, which reported that the risk of penile cancer in Japan, Norway, and Sweden (countries with a low rate of circumcision) is about the same (1 in 100,000 per year) as in the US.[18]
HPV Vaccine
Main article:
HPV vaccineInfection with HPV is associated with some penile cancers. A quadri-valent vaccine (Gardasil) to prevent infection by the four most common variants of HPV has been developed, successfully tested, and approved by the US Food and Drug Administration for females between the ages of 9 and 26, and as of 2009, males between the ages of 16 and 26.[19] Gardasil has been shown to also be effective in males, and has been approved by the FDA to be marketed as such.[20]
See also
References
- ^ "Cancer Research UK: Types of penile cancer". http://www.cancerhelp.org.uk/help/default.asp?page=22698. Retrieved 2008-06-24.
- ^ "ACS :: What Are the Key Statistics About Penile Cancer?". Archived from the original on 2007-10-30. http://web.archive.org/web/20071030194444/http://www.cancer.org/docroot/CRI/content/CRI_2_4_1X_What_are_the_key_statistics_for_penile_cancer_35.asp?sitearea=. Retrieved 2007-12-13.
- ^ "Penis Cancer". http://www.medicinenet.com/penis_cancer/page2.htm. Retrieved 2008-06-24.
- ^ "ACS :: What Are the Risk Factors for Penile Cancer?". Archived from the original on 2007-09-26. http://web.archive.org/web/20070926223401/http://www.cancer.org/docroot/CRI/content/CRI_2_4_2X_What_are_the_risk_factors_for_penile_cancer_35.asp?sitearea=. Retrieved 2007-12-13.
- ^ "bmj.com Rapid Responses for Rickwood et al., 321 (7264) 792-793". http://bmj.bmjjournals.com/cgi/eletters/321/7264/792#110919. Retrieved 2007-12-13.
- ^ Kochen M, McCurdy S (1980). "Circumcision and the risk of cancer of the penis. A life-table analysis". Am. J. Dis. Child. 134 (5): 484–6. doi:10.1001/archpedi.134.5.484. PMID 7377156.
- ^ Ronald L. Poland (1990). "The question of routine neonatal circumcision". The New England Journal of Medicine 22 (18): 1312–1315. http://www.cirp.org/library/general/poland/.
- ^ Maden C, Sherman KJ, Beckmann AM, et al. (1993). "History of circumcision, medical conditions, and sexual activity and risk of penile cancer". J. Natl. Cancer Inst. 85 (1): 19–24. doi:10.1093/jnci/85.1.19. PMID 8380060.
- ^ Schoen EJ, Oehrli M, Colby C, Machin G (2000). "The highly protective effect of newborn circumcision against invasive penile cancer". Pediatrics 105 (3): E36. doi:10.1542/peds.105.3.e36. PMID 10699138.
- ^ Tsen HF, Morgenstern H, Mack T, Peters RK (2001). "Risk factors for penile cancer: results of a population-based case-control study in Los Angeles County (United States)". Cancer Causes Control 12 (3): 267–77. doi:10.1023/A:1011266405062. PMID 11405332.
- ^ a b Dillner J, von Krogh G, Horenblas S, Meijer CJ (2000). "Etiology of squamous cell carcinoma of the penis". Scand J Urol Nephrol Suppl 34 (205): 189–93. doi:10.1080/00365590050509913. PMID 11144896.
- ^ Gajalakshmi CK, Shanta V (1993). "Association between cervical and penile cancers in Madras, India". Acta Oncol 32 (6): 617–20. doi:10.3109/02841869309092439. PMID 8260177.
- ^ Sánchez Merino JM, Parra Muntaner L, Jiménez Rodríguez M, Valerdiz Casasola S, Monsalve Rodríguez M, García Alonso J (2000). "[Epidermoid carcinoma of the penis]" (in Spanish; Castilian). Arch. Esp. Urol. 53 (9): 799–808. PMID 11196386.
- ^ Schoeneich G, Perabo FG, Müller SC (1999). "Squamous cell carcinoma of the penis". Andrologia 31 Suppl 1: 17–20. doi:10.1111/j.1439-0272.1999.tb01445.x. PMID 10643514.
- ^ Castellsagué X, Bosch FX, Muñoz N, et al. (2002). "Male circumcision, penile human papillomavirus infection, and cervical cancer in female partners". N. Engl. J. Med. 346 (15): 1105–12. doi:10.1056/NEJMoa011688. PMID 11948269.
- ^ Baldwin SB, Wallace DR, Papenfuss MR, Abrahamsen M, Vaught LC, Giuliano AR (2004). "Condom use and other factors affecting penile human papillomavirus detection in men attending a sexually transmitted disease clinic". Sex Transm Dis 31 (10): 601–7. doi:10.1097/01.olq.0000140012.02703.10. PMID 15388997.
- ^ Svare EI, Kjaer SK, Worm AM, Osterlind A, Meijer CJ, van den Brule AJ (2002). "Risk factors for genital HPV DNA in men resemble those found in women: a study of male attendees at a Danish STD clinic". Sex Transm Infect 78 (3): 215–8. doi:10.1136/sti.78.3.215. PMC 1744457. PMID 12238658. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1744457.
- ^ Wallerstein E (February 1985). "Circumcision. The uniquely American medical enigma". Urol. Clin. North Am. 12 (1): 123–32. PMID 3883617.
- ^ Crum C, Jones C, Kirkpatrick P (August 2006). "Quadrivalent human papillomavirus recombinant vaccine". Nature reviews. Drug discovery 5 (8): 629–30. doi:10.1038/nrd2117. PMID 16918020. http://www.nature.com/nrd/journal/v5/n8/full/nrd2117.html.
- ^ Cortez, Michelle Fay and Pettypiece, Shannon. "Merck Cancer Shot Cuts Genital Warts, Lesions in Men". Bloomberg News. (Bloomberg.com) 13 Nov 2008.
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Related
diseases |
Cervical cancer ·
Factor in other cancers (Anal, Vaginal, Vulvar, Penile, Head and neck cancer (HPV-positive oropharyngeal cancer)) ·
Warts ( genital, plantar, flat, Laryngeal papillomatosis), Epidermodysplasia verruciformis, Focal epithelial hyperplasia, Papilloma
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| Colposcopy |
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| History |
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cutn/syst (hppv/hiva, infl/zost/zoon)/epon
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drugJ(dnaa, rnaa, rtva, vacc)
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