[The study on the specific eruptions of malignant lymphoma. I. Clinical, pathological and immunopathological characters].

We investigated 31 cases of cutaneous malignant lymphoma diagnosed by skin biopsy during about 11 years at the University of Tsukuba Hospital. The specific eruption was occurred in 17.7% of all malignant lymphomas at the hospital. The skin was primarily affected in 5.8% of all malignant lymphomas including Hodgkin disease, and in 6.9% excluding Hodgkin disease. We divided 31 cases into 3 groups; Group A is the primary cutaneous lymphoma, and Group B and C are the secondary cutaneous lymphoma. The skin lesions of Group B share the major part. On the other hand, that of Group C is minimal and transient. The differences between group A/B and group C were the high frequency of epidermotropism. The T cell dominance, the widespread eruption and the variety of the eruptions for one case in Group A/B. Group A differed from group B/C by the specific plaque, and from Group B by the high frequency of Pautrier's microabscess. B cell lymphomas did not show dermal-epidermotropism as well as epidermotropism.