Abstract: The growth factor receptor c-kit (CD117) is expressed in immature T-cells and in some advanced forms of mycosis fungoides. c-kit gene mutation results in unrestricted neoplastic proliferation. We aimed to detect by PCR the most frequent exon mutations in seventeen plaque-stage MF patients, in their perilesional skin and in healthy skin donors. We secondarily evaluated CD117 expression by immunohistochemistry in plaque-stage and tumor-stage MF. We detected no mutation in c-kit gene and low CD117 expression was confirmed on atypical cells in one patient. Complete c-kit exon and intron sequences should be assessed and more sensitive sequencing method could be also applied.

Abstract: Pyoderma gangrenosum may precede, coexist or follow diverse systemic diseases. The bullous variety is usually associated with hematologic disorders. From 31 patients with pyoderma gangrenosum diagnosed in our hospital during 10 years, only 2 presented with the bullous type. One patient had previous diagnosis of chronic myeloid leukemia. Both had fast-progressive, painful lesions, and both showed an excellent response to systemic corticosteroids. In less than 3 months the lesions recurred simultaneously with the progression of chronic myeloid leukemia in one patient and with the initial diagnosis of acute myeloid leukemia in the other one. They died in less than four weeks. These findings emphasize the importance of its timely diagnosis. Cutaneous lesions could be the first predictor of an underlying disease.