Primary CD30-positive cutaneous T-cell lymphomas and lymphomatoid papulosis frequently express cytotoxic proteins

Alms: To analyse the relationship between expression of cytotoxic proteins. histopathology and the CD30 status in primary cutaneous T-cell disorders, we investigated the expression of TIA-1, granzyme B and perforin in CD30 ne gative and CD30 positive cutaneous T-cell lymphomas (CTCL) and lymphomatoid papulosis (LP). Methods and results: We studied 26 cases of CTCL and 12 cases of LP for the expression of TIA-1, granzyme B and perforin which are granule-associated proteins of cytotoxic lymphocytes involved in the mechanism of apoptosis. W e showed that most cases (10/13) of CD30 negative pleomorphic lymphomas exp ressed cytotoxic proteins only in scattered, apparently reactive lymphocyte s, the exception being one CD8+ CTCL and two gamma delta subcutaneous 'pann iculitis-like' T-cell lymphomas. We also showed that at least one cytotoxic protein was expressed in a proportion of neoplastic cells in 77% (10/13) o f CD30+ T-cell lymphomas (3/4 pleomorphic and 7/9 anaplastic) and in a prop ortion of atypical cells in 75% (9/12) of LP. Conclusions: Our findings show a strong correlation between the CD30 phenot ype and the expression of cytotoxic proteins in primary CTCL. In addition, these results provide further evidence for an overlap between lymphomatoid papulosis and cutaneous CD30+ pleomorphic and anaplastic lymphomas. These e ntities, which belong to the spectrum of CD30 positive cutaneous T-cell lym phoproliferations, appear to be derived from cytotoxic cells.