What is the most common melanoma in patients with dark skin?
Nodular melanoma accounts for 15 to 30% of melanomas, and this variant is unique because it begins with a vertical growth phase that partly accounts for its worse prognosis. Lentigo maligna is typically found in older individuals and primarily located in the head and neck region. The acral lentiginous variant accounts for 29 to 72% of melanomas in dark-skinned individuals, is occasionally seen in Caucasians, and is found on palmar, plantar, and subungual surfaces.
Kaposi sarcoma:
Kaposi sarcoma is diagnosed after the fifth decade of life and predominantly found on the skin but can occur anywhere in the body. In North America, the Kaposi sarcoma herpes virus is transmitted via sexual and nonsexual routes and predominantly affects individuals with compromised immune systems such as those with HIV and transplant recipients on immunesuppressing medications. Clinically, Kaposi sarcoma appears as multifocal, rubbery blue nodules. Treatment of acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma is with antiviral therapy, and many patients experience a dramatic treatment response. Those individuals who do not respond and have limited mucocutaneous disease may benefit from cryotherapy, photodynamic therapy, radiation therapy, intralesional injections, and topical therapy. Surgical biopsy is important for disease diagnosis, but given the high local recurrence and the fact that Kaposi sarcoma represents more of a systemic rather than local disease, the benefit of surgery is limited and generally should not be pursued except for palliation.
The following is NOT a prognostic indicator for patients with a sentinel node containing metastatic melanoma:
Melanoma is characterized according to the American Joint Committee on Cancer (AJCC) as localized disease (stage I and II), regional disease (stage III), or distant metastatic disease (stage IV). Overall tumor thickness, ulceration, and mitotic rate are the most important prognostic indicators of survival. If a sentinel node contains metastatic melanoma, the number of positive nodes; thickness, mitotic rate, and ulceration of the primary tumor; and patient age determine prognosis. With clinically positive nodes, the number of positive nodes, primary tumor ulceration, and patient age determine prognosis. The site of metastasis is strongly associated with prognosis for stage IV disease, and elevated lactate dehydrogenase (LDH) is associated with a worse prognosis.
A patient with a 5-mm deep melanoma of the thigh and no clinically positive nodes should undergo which procedure?
Nonmetastatic in-transit disease should undergo excision to clear margins when feasible. However, disease not amenable to complete excision derives benefit from isolated limb perfusion (ILP) and isolated limb infusion (ILI) (Fig. below). These two modalities are used to treat regional disease, and their purpose is to administer high doses of chemotherapy, commonly melphalan, to an affected limb while avoiding systemic drug toxicity. ILl was shown to provide a 31% response rate in one study, while hyperthermic ILP provided a 63% complete response rate in an independent study.
Isolated limb infusion. Schematic of isolated limb infusion of lower extremity. (From Thompson J F, Kam PC Isolated limb infusion for melanoma: a simple but effective alternative to isolated limb perfusion.
A 65-year-old patient who spends winters in Florida presents with a painless, ulcerated lesion on his right cheek. The lesion has been present for 1 year. Physical examination of the patient's neck reveals no lymph node enlargement. The most likely diagnosis is:
The most common form of BCC (60%) is the nodular variant, characterized by raised, pearly pink papules and occasionally a depressed tumor center with raised borders giving the classic "rodent ulcer" appearance. This variant tends to develop in sun-exposed areas of individuals older than 60 years. Superficial BCC accounts for 15% ofBCC, is diagnosed at a mean age of 57 years, and typically appears on the trunk as a pink or erythematous plaque with a thin pearly border. The infiltrative form appears on the head and neck in the late 60s with similar clinical appearance to the nodular variant. An important variant to keep in mind is the pigmented variant of nodular BCC because this may be difficult to differentiate from nodular melanoma. Other important subtypes include the morpheaform variant, accounting for 3% of cases and characterized by indistinct borders with a yellow hue, and fibroepithelioma of Pinkus. Histologic subtypes of BCC include nodular and micronodular (50%), superficial (15%), and infiltrative.
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