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melanomaA tumour that comprises 1–3% of all new cancers (18,000/year) and causes 6500 deaths/year (US), most age 30–50; melanoma is increasing at ± 7%/year, and now affects 9/105 (primarily the head and neck) in men and 12/105 (primarily legs) in women; it is rare but more aggressive in children.
Giant congential melanocytic nevus, dysplastic nevus, xeroderma pigmentosum, immunodeficiency, moles with persistent pigment changes (especially > age 15), large or irregularly pigmented lesions, familial moles, congenital moles, Caucasian (12-fold greater risk than Black), previous melanoma, melanoma in 1st-degree relative, immunosuppression, photosensitivity, increased sun exposure.
Site of metastasis
Liver, lung, intestine, pancreas, adrenal, heart, kidney, brain, spleen, thyroid.
Wide excision; chemo- and radiation are essentially useless.
Local recurrence common; many metastasise; 5-year survival reflects stage when diagnosed.
Poor prognostic factors
Large size, paranasal/nasopharyngeal location, vascular invasion, high mitotic activity, marked cellular pleomorphism, distant metastases.
Stages of melanoma
▪ Stage I—Confined to epidermis and/or upper dermis, and measures ≤ 1.5-mm thick.
▪ Stage II—1.5-mm to 4-mm thick; spread to lower dermis but not beyond or to adjacent lymph nodes.
▪ Stage III—Any of the following:
– > 4-mm thick;
– Spread beyond the skin;
– Satellite lesions within 2 cms of the original tumour; or
– Spread to nearby lymph nodes or satellite lesions between original and regional lymph nodes.
▪ Stage IV—Metastases to other organs or to lymph nodes far from the original lesion.
Types of melanoma
Acral lentiginous melanoma
A rare, flat, palmoplantar or subungual lesion more common in non-whites; average 5-year survival < 50%; unrelated to actinic exposure, but possibly related to ectopic pigmentation.
Rare, poorly differentiated, and occurs in those with a previous pigmented melanoma; since the Fontana-Masson stain is rarely positive in amelanotic melanoma, special studies are necessary, including immunoperoxidase staining with antibodies to the S-100 antigen and ultrastructural examination for presence of premelanosomes.
Comprises 10% of melanomas; affects those > age 60; appears as flat, indolent lesions on face, arising from a premalignant freckle with greater than 90% 5-year survival; aetiologically linked to prolonged actinic exposure.
15% of cases; similar clinically to superficial spreading melanoma; 50% average 5-year survival.
1/3 of lentigo maligna (Hutchinson’s freckle) progress to malignant melanoma after 10–15 years.
Superficial spreading melanoma
70% of cases; affects ages 30 to 60, especially female in lower legs or trunk, as a flat lesion (radial growth phase) that may be present for months to years; average 5-year survival 75%; aetiologically linked to recreational actinic exposure.
Thin melanoma (Stage-I cutaneous melanoma)
A lesion measuring < 1 cm in diameter; virtually 100% survival.
mel·a·not·ic car·ci·no·ma(mel'ă-not'ik kahr'si-nō'mă)
carcinoma(kar?sin-o'ma ) [ carcin- + -oma]
Optimal patient care includes: identifying and explaining to patient and family the type of cancer and its typical natural history; options for treatment, side effects of treatments, expected response of the cancer to the treatment, best predictions for recovery and life expectancy, availability of clinical trials, alternative and complementary therapies, and the potential benefit of referral to specialty cancer centers.
acinar cell carcinoma of the pancreas
alveolar cell carcinoma
basal cell carcinomaAbbreviation: BCC
bronchogenic carcinomaLung cancer.
choroid plexus carcinoma
carcinoma of the colonSee: colorectal cancer
colorectal carcinomaColorectal cancer.
ductal carcinoma in situ of breastSee: ductal carcinoma in situ of breast
epidermoid carcinomaSquamous cell carcinoma.
giant cell carcinoma
carcinoma in situAbbreviation: CIS
oat cell carcinoma
carcinoma of pancreasPancreatic cancer.
pancreatic carcinomaPancreatic cancer.
papillary carcinoma of the thyroidSee: papillary carcinoma of the thyroid
renal cell carcinoma
Because of its location in the retroperitoneum, renal cell carcinoma may grow to a relatively large size before it manifests obvious symptoms. The most common findings are blood in the urine (hematuria), flank pain, or a flank mass. Some patients develop fevers, weight loss, or symptoms caused by hormones excreted by the tumor. These hormones (parathyroid-like hormone or erythropoietin) occasionally cause hypercalcemia or abnormal increases in the red blood cell count (erythrocytosis).
Surgical removal of the affected kidney may be curative for those patients whose tumor has not spread outside the perirenal fascia. Treatment options are less successful for patients with metastatic disease because renal cell carcinomas are relatively resistant to chemotherapy.