In the ABCDE of melanoma, the D stands for diameter greater than:
Melanoma most commonly manifests as cutaneous disease, and clinical characteristics include an Asymmetric outline, changing irregular Borders, Color variations, Diameter greater than 6 mm, and Elevation (ABCDE). Other key clinical characteristics include a pigmented lesion that has enlarged, ulcerated, or bled. Amelanotic lesions appear as raised pink, purple, or normal-colored skin papules and are often diagnosed late.
The most common site of distant metastasis for melanoma:
The most common sites of distant metastasis are the lungs and liver followed by the brain, gastrointestinal tract, distant skin, and subcutaneous tissue. A limited subset of patients with small-volume, limited distant metastases to the brain, gastrointestinal tract, or distant skin will be cured with resection or gamma knife radiation. Liver metastases are better dealt without surgical resection unless they arise from an ocular primary.
The most common subtype of melanoma is:
Melanoma growth most commonly starts as a localized, radial growth phase followed by a vertical growth phase that determines metastatic risk. The subtypes of melanoma include lentigo maligna, superficial spreading, acral lentiginous, mucosal, nodular, polypoid, desmoplastic, amelanotic, and soft tissue. The most common subtype is superficial spreading, accounting for 70% of cases.
Ocular melanoma:
Ocular melanoma is the most common noncutaneous disease site, and treatment includes photocoagulation, partial resection, radiation, or enucleation. Ocular melanomas exclusively metastasize to the liver and not regional lymph nodes, and some patients benefit from liver resection.
The following is NOT true in regard to Merkel cell carcinoma:
This is a rare and aggressive neuroendocrine tumor of the skin most commonly found in white men and diagnosed at a mean age of 70 years. Risk factors include UV radiation, PUVA, and immunosuppression. Approximately one in three cases present on the face, with the remainder occurring on sun-exposed skin. A rapidly growing, flesh-colored papule or plaque characterizes the disease. Regional lymph nodes are involved in 30% of patients, and 50% will develop systemic disease (skin, lymph nodes, liver, lung, bone, brain). There are no standardized diagnostic imaging studies for staging, but computed tomography ( CT) of the chest, abdomen, and pelvis and octreotide scans may provide useful information when clinically indicated. After examining the entire skin for other lesions, treatment should begin by evaluating the nodal basins.
Recurrence is common, and one study of95 patients showed a 47% recurrence, with 80% of recurrences occurring within 2 years and 96% occurring within 5 years. Regional lymph node disease is common, and 70% of patients will have nodal spread within 2 years of disease presentation. Five-year overall survival of head and neck disease in surgically treated patients is between 40 and 68%.
Click to expand