p53 and bcl-2 expression do not correlate with prognosis in primary cutaneous large T-cell lymphomas.

Overexpression of p53 protein in cutaneous T-cell lymphoma (CTCL) has been reported in primary cutaneous large T-cell lymphomas (PCLTCL) and has been associated with tumor progression and transformation in mycosis fungoides. However, the prognostic significance of p53 expression has not been studied thus far. In the present study we investigated the expression of p53 as well as bcl-2 protein in 27 PCLTCL, including 19 CD30-positive and 8 CD30-negative lymphomas, retrieved from the registry of the Dutch Cutaneous Lymphoma Working Group. The results were correlated with follow-up data and proliferative activity, as assessed by the percentage of MIB-1 positive tumor cells. Overexpression of p53 protein, defined as nuclear staining of more than 5% of the tumor cells, was found in 10 of 27 cases (37%), including 6 of 19 (32%) CD30+lymphomas and 4 of 8 (50%) CD30-PCLTCL. bcl-2 protein was expressed in 6 of 19 (32%) CD30+lymphomas and in only 1 of 8 (12%) CD30-PCLTCL. However, no significant correlation between p53 or bcl-2 expression and prognosis was found, neither in the whole group, nor within the CD30+ or CD30- group. In addition, no relationship between p53 expression and proliferative activity was found. The results confirm that p53 expression is more common in PCLTCL than in mycosis fungoides and Sézary syndrome. However, neither p53 nor bcl-2 expression correlated with survival or proliferative activity.