Rare variants of malignant melanoma

Abstract

The personal experience with 5 rare types of malignant melanoma is reviewed to point out some of the practical problems in the diagnosis and management of these tumors. The rare forms discussed are conjunctival, nasal, oral, vulvar, and penile melanomas. All pigmented lesions in the oral cavity, but not the penis or vulva, should be prophylactically excised as lesions in the mouth have a higher malignant potential. Local excision of all 5 forms of primary melanomas, no matter how locally advanced they may be, is the sole treatment. Nevertheless, anatomic constraints often preclude surgery with generous margins and consequently local recurrence, particularly for conjunctival, nasal, and oral primary lesions, is usually the major first failure in treatment. Lymph node dissection is only performed if the regional nodes are palpable at the time of first presentation. Elective lymph node dissections are not performed since the patients are often elderly, the lymphatic drainage is usually ambiguous or multiple, and the disease tends to spread hematogenously rather than lymphatically. Surgery still remains the cornerstone of treatment for these rare forms of melanoma but prognosis is very poor since surgery is often a palliative rather than a curative measure. Improved survival may depend on identifying more effective chemotherapeutic and immunologic agents.

Primary Mucosal and Glans Penis Melanomas: The Sydney Melanoma Unit Experience

“…As in other series, the lesions most frequently developed on the mucosa overlying the hard palate 2 , 8 , 10 –12 , 18 . Very often oral mucosal melanoma does not produce troublesome symptoms and sometimes the tumour is found incidentally by a dentist, as was the case with one of the SMU patients 12 , 17 , 18 , 20 …”

“…The penis is a rare site for primary malignant melanoma, occurring much less commonly than vulval melanoma 10 . It accounts for 0.6–1.4% of penile malignancies in most large series 5 , 20 , 35 , 36 …”

Malignant melanoma of the glans penis and male urethra Glans penis ve erkek üretrasının primer malign melanomu

“…Whereas some authors recommended an aggresive surgical approach with total amputation of the penis, perineal urethrostomy and radical inguinal, iliac and obturator lymph node dissection (8,9,10). But Stillwell et al, belive that conservative penile surgery (local excision with 3 to 5 cm margin or distal partial penectomy) with an appropriate margin when inguinal nodes are nonpalpable in a patient with thin lesions (less than 1.5 mm) and prophylactic superficial inguinal node dissection for those greather than 1.5 mm 3 thick and most authors agree with these treatment (11,12,13). Some others reported that sentinel lymphadenectomy using radiocolloid mapping and dye localization avoided potential morbidity of bilateral superficial inguinal node dissections and allowed accurate staging for further treatment and prognosis (14,15).…”

“…The combination chemotherapy consisting of six cycles DTIC, BCNU, cisplatin and tamoxifen gives the best result. The respond rate changes between %15 to %45 (11)(12)(13)(14)(15)(16). There has been reported other treatment options; such as radiotherapy, immunotherapy with BCG, endolymphatic iodine-iodized oil infusion but the result are not superior to chemotherapy (2).…”

Penile primary melanoma: analysis of 6 patients treated at Brazilian national cancer institute in the last eight years

“…All patients underwent conservative treatment, including the amputation of the glans in 6 patients, local excision in 3 and partial penile amputation in 2 (3). They believe that conservative surgery such as local excision or partial penile amputation with appropriate safety margin (3-5 cm), can be performed in superficial lesions (less than 1.5 mm) or associated with superficial bilateral inguinal lymphadenectomy in deeper lesions (greater to 1.5 mm), thus being suitable for melanomas stage T1 or T2 (27)(28)(29). However, lack further evidence for defining the optimal surgical margin for lesions with a thickness between 1 and 2 mm, and it is the current trend to practice banks of 2 cm.…”