Merkel cell carcinoma: analysis of clinical, histologic, and immunohistologic features of 132 cases with relation to survival.
BACKGROUND
Merkel cell carcinoma (MCC) is an uncommon malignancy of the skin and has a high rate of recurrence and metastasis. There have been few large studies of the biologic behavior of MCC.


OBJECTIVE
Our purpose was to determine whether there were clinical or histologic features of MCC that predict its biologic behavior.


METHODS
We reviewed 132 cases of MCC. Clinical and histologic features were correlated with follow-up information to determine whether any of these were associated with prognosis.


RESULTS
Clinical information was available on 126 patients; 57 were alive, 1 was alive with tumor, 28 died of tumor, 27 died from other causes, and 14 were lost to follow-up. MCC on the buttock/thigh area or trunk had the worst prognosis, and those on the distal extremities had the best prognosis; however, the difference was not statistically significant. Sex and age were not significant factors. Small cell size, high mitotic rate, and large tumor size were associated with a low survival rate. When cell size was excluded, male sex and depth of invasion were associated with a worse survival, although these were not statistically significant.


CONCLUSIONS
Cell size, mitotic rate, and tumor size are significant factors in relation to the biologic behavior of MCC.
Skelton
H G
HG
Laboratory Corporation of America, Herndon, Virginia, USA.
Smith
K J
KJ
Hitchcock
C L
CL
McCarthy
W F
WF
Lupton
G P
GP
Graham
J H
JH
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000943:Antigens, Differentiation / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D018959:CD57 Antigens / Q000032:analysis; D015266:Carcinoma, Merkel Cell / Q000401:mortality / Q000473:pathology* / Q000556:secondary; D002864:Chromogranins / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D015999:Multivariate Analysis; D010751:Phosphopyruvate Hydratase / Q000032:analysis; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D009418:S100 Proteins / Q000032:analysis; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000401:mortality / Q000473:pathology*; D016019:Survival Analysis
D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm; D018959:CD57 Antigens; D002864:Chromogranins; D009418:S100 Proteins; D010751:Phosphopyruvate Hydratase