An immunophenotypic survey of malignant melanomas.
An immunohistochemical study of 106 malignant melanoma specimens from 59 patients, using formalin-fixed, paraffin-embedded material, is reported. Negativity for HMB-45 was seen in 11% of specimens. The rate of positivity with CAM 5.2 was 7%. One specimen showed alpha-smooth muscle actin (alpha SMA) positivity. For 11 of the 12 cases in which anomalous immunophenotypes were seen, multiple specimens were available; nine of these showed evidence of an alteration in the immunophenotype between specimens. Comparing the primary tumours with local recurrences and metastases, there was, variously, loss of HMB-45, S-100 protein and NKI/C3 positivity, and acquisition of CAM 5.2 and alpha SMA positivity. In some cases, the change of immunophenotype appeared to occur in a single step. However, one case with six consecutive specimens showed evidence of progressive loss of HMB-45, S-100 protein and NKI/C3 with concomitant gain of CAM 5.2 staining. The implications for the use of immunophenotyping in diagnostic practice are discussed.
Bishop
P W
PW
Department of Pathological Sciences, University of Manchester, UK.
Menasce
L P
LP
Yates
A J
AJ
Win
N A
NA
Banerjee
S S
SS
D014408:Biomarkers, Tumor; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008545:Melanoma / Q000473:pathology* / Q000556:secondary; D012878:Skin Neoplasms / Q000473:pathology
D014408:Biomarkers, Tumor