• PDF / 172,215 Bytes
• 1 Pages / 595.245 x 841.846 pts (A4) Page_size
• 73 Downloads / 167 Views

DOWNLOAD

REPORT

---

1

S

Phenotypic switch from primary cutaneous T-cell lymphoma to cutaneous γδ T-cell lymphoma: case report In a case series of two patients, a 92-year-old woman was described, who developed phenotypic switch from primary cutaneous T-cell lymphoma (CTCL) to cutaneous γδ T-cell lymphoma following treatment with cyclophosphamide, etoposide and prednisone for CTCL. The woman, who had a history of colorectal cancer, presented with pruritic and flakey skin lesions on her ears, face and chest. Few months later, a biopsy of the left cheek and scalp was performed which showed a lichenoid deep, periadenexal, and severely epidermotropic infiltrate of large mononuclear cells in the dermis and epidermis which demonstrated CD3 and CD4 (4:1 CD4/CD8), but had a 40–50% decreased expression of CD7. βF1, TCRδ, Granzyme B, and TIA-1 were also found to be negative. T-cell receptor (TCR) gene rearrangement studies revealed monoclonal peaks in the γ (V1–8, 255 bp and V11, 155 bp) and β regions (Tube C 312 bp). She was diagnosed with CTCL manifesting as mycosis fungoides stage IIB. Further PET/CT scan demonstrated that the CTCL was confined to the skin and subcutis. She started receiving radiation therapy as well as chemotherapy with cyclophosphamide, prednisone and etoposide [routes and dosages not stated]. Initially, her lesions shrunk. However, six months after the initiation of chemotherapy, her lesions recurred and started to enlarge. A repeat biopsy of the ulcerated cutaneous chest wall lesion showed diffuse sheets of medium to large-sized neoplastic lymphocytes. Investigation also revealed that some of the neoplastic cells were rimming adipocytes and had a panniculitis-like pattern, but extensively involved the dermis as well. No identifiable epidermis was located on any sections. Flow cytometry demonstrated that the cells expressed CD3, CD26, CD45, CLA (cutaneous lymphocyte-associated antigen), TCR γδ, Granzyme B, and TIA-1, but not CD2, CD4, CD5, CD7, CD 8 , CD 30 , CD 56 or TCRαβ. Immunohistochemistry showed positive result for TIA-1, Granzyme B, and CD3 and negative for CD5 and CD7. In addition, TCR gene rearrangement study revealed same gene rearrangements as observed in previous investigation, confirming that this was the same neoplasm as previous. Based on these findings, she was diagnosed with cutaneous γδ T-cell lymphoma due to phenotypic switch from primary CTCL. Chemotherapy with cyclophosphamide, prednisone and etoposide was considered as one of the risk factor for the phenotypic switch. Within a month, she died due to cutaneous γδ T-cell lymphoma. Author comment: "It is unclear if [phenotypic switch] is related to treatment, genetic alterations, tumor microenvironment, or chance." "A [phenotypic switch] usually occurs after treatment and is defined by a tumor retaining its genetic signature, but its phenotype is altered." Marks E, et al. Two cases of phenotypic switch of primary cutaneous T cell lymphoma after treatment with an aggressive course and review of the literature. Virchows Archiv: an international journal o