Melanoma markers in angiomyolipoma of the liver and kidney: a comparative study.

Abstract

CONTEXT:

Melanoma markers, especially the new microphthalmia transcription factor (mitf), have not been previously compared in hepatic and renal angiomyolipomas.

OBJECTIVES:

To evaluate expression of the novel melanocytic markers mitf and tyrosinase in angiomyolipomas, and to compare these markers with the established markers HMB-45 and melan-A in both hepatic and renal tumors.

DESIGN:

Clinical, histopathologic, and immunohistochemical features of 15 hepatic angiomyolipomas were compared with those of 10 renal angiomyolipomas.

RESULTS:

No significant differences between patients with hepatic angiomyolipomas and renal angiomyolipomas were found with respect to age, gender, race, and tumor size. Hepatic angiomyolipomas exhibited a predominance of the epithelioid smooth muscle cell component, in contrast to their renal counterparts, which were predominantly spindled. The smooth muscle cells expressed HMB-45 in 100% of cases in both groups, melan-A in 14 of 15 hepatic angiomyolipomas and 8 of 9 renal angiomyolipomas, mitf in 5 of 12 hepatic angiomyolipomas versus 6 of 10 renal angiomyolipomas, and tyrosinase in 3 of 12 and 2 of 10 hepatic angiomyolipomas and renal angiomyolipomas, respectively. The extent and intensity of immunostaining with HMB-45 and melan-A were dependent on whether spindled or epithelioid cells predominated; the epithelioid cells showed stronger and more widespread reactivity than the spindled cells.

CONCLUSION:

We believe that the best immunohistochemical marker for confirming the diagnosis of angiomyolipoma is HMB-45, followed by melan-A. Routine use of mitf and/or tyrosinase is not indicated.

• Authors: Hala R Makhlouf, Kamal G Ishak, Raj Shekar, Isabell A Sesterhenn, Denise Y Young, Julie C Fanburg-Smith
• Journal: Archives of pathology & laboratory medicine (Arch Pathol Lab Med) Vol. 126 Issue 1 Pg. 49-55 (Jan 2002) ISSN: 0003-9985 [Print] United States
• PMID: 11800647 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Antigens, Neoplasm
• Biomarkers, Tumor
• DNA-Binding Proteins
• MART-1 Antigen
• MITF protein, human
• MLANA protein, human
• Melanoma-Specific Antigens
• Microphthalmia-Associated Transcription Factor
• Neoplasm Proteins
• Transcription Factors
• Monophenol Monooxygenase

Topics

• Adult
• Aged
• Angiomyolipoma (metabolism, pathology)
• Antigens, Neoplasm
• Biomarkers, Tumor (metabolism)
• DNA-Binding Proteins (metabolism)
• Female
• Humans
• Immunohistochemistry
• Kidney Neoplasms (metabolism, pathology)
• Liver Neoplasms (metabolism, pathology)
• MART-1 Antigen
• Male
• Melanoma-Specific Antigens
• Microphthalmia-Associated Transcription Factor
• Middle Aged
• Monophenol Monooxygenase (metabolism)
• Neoplasm Proteins (metabolism)
• Transcription Factors (metabolism)