Case 244 - Discussion

Uploaded: 2008-06-14, Updated: 2008-06-14

 

 

HMB45 MART1
MITF S100
  • Clinical History: Patient had a desmoplastic melanoma of the right forearm resected recently.

  • Microscopic Description: The large lymph node is entirely effaced by spindle neoplastic cells in bundles or fascicles with focal myxoid degeneration. Most of the tumor cells are intermediate in size with moderate to abundant pale cytoplasm and round, oval or spindle nuclei. The chromatin is rather evenly disposed without visible nucleoli. Scattered epithelioid neoplastic cells are present. Frequent mitotic figures are present. By immunostains, the scattered epithelioid cells but not the spindle cells are positive for MITF, S100, MUC-1, and HMB45. Both the epithelioid and spindle tumor cells are positive for vimentin but negative for CK AE1:3 and LCA.

  • Final Diagnosis: Metastatic desmoplastic melanoma

 

 

The Key Features

 

CLINICAL FEATURES

 

GROSS FINDINGS

 

MICROSCOPIC FINDINGS

 

SUBTYPES

 

DIFFERENTIAL DIAGNOSES

 

IMMUNOHISTOCHEMISTRY AND SPECIAL STAINS

 

ELECTRON MICROSCOPIC FINDINGS

 

CYTOGENETIC STUDIES

 

TREATMENT AND PROGNOSIS

 

REFERENCES