Anaplastic large cell Ki‐1 lymphoma. Delineation of two morphological types

Abstract

This report describes 16 cases of the recently recognized anaplastic large cell Ki-1 lymphoma. The disease showed a male:female ratio of 2.2:1 and a bimodal age distribution with peaks in the third and eighth decades. The clinical presentation was highly variable, with lymph node, skin, bone and gastrointestinal tract being the most commonly affected sites. The lymph nodes usually showed subtotal or sinusoidal involvement, and parenchymal fibrosis was common. The large neoplastic cells were almost invariably admixed with many reactive small lymphocytes, histiocytes and/or neutrophils. Two cytological types could be delineated: type I (pale cell, four cases) consisted of large polygonal cells with distinct pink-staining cell membrane and pale cytoplasm and pleomorphic nuclei showing marked chromatin clearing; and type II (basophilic cell, 12 cases) consisted of round or oval cells with basophilic cytoplasm and/or paranuclear pale hof, pleomorphic nuclei often reniform or lobulated and with frequent multinucleated wreath-like and Reed-Sternberg-like cells. Immunohistochemical studies showed that nine cases (56.3%) exhibited a T-cell phenotype, three cases (18.8%) each exhibited a B-cell or null-cell phenotype, while one case exhibited both T- and B-cell markers. Cutaneous involvement at presentation was associated with a favourable outcome, and spontaneous regression was common. For patients with non-cutaneous presentation, the prognosis was relatively good for young patients treated with aggressive chemotherapy, but was grave for old patients.

Anaplastic Large Cell Lymphoma: The Shifting Sands of Diagnostic Hematopathology

“…In some series a bi-modal age distribution is seen (19,30,46). However, cases of ALCL in the elderly usually are t(2;5) or ALK negative, and probably constitute an unrelated clinicopathologic entity.…”

Pathobiology of NPM-ALK and variant fusion genes in anaplastic large cell lymphoma and other lymphomas

“…Histological variations within the common type have also been variously described by investigators as pale vs basophilic and monomorphic vs pleomorphic. 52,55 The less common variants include HD-like variant (6%), small cell predominant variant (6%), and lymphohistiocytic variant (4%) ( Table 3). For reviews on the histology of ALCL and its morphological variants see Refs 43,67,68.…”

Anaplastic KI-1 (CD30) Positive Large Cell Lymphoma of the Stomach Mimicking Hodgkin's Disease: A Case Report and Review of the Literature

“…20 Primary CD30-positive ALCL of stomach are very rare. 12,13,27,28 In our patient, a diagnosis of ALCL CD30+ was made, where the tumor cells were arranged in sheets, having abundant faintly eosinophilic cytoplasm and large nuclei with prominent eosinophilic nucleoli. A variable proportion of large, bizarre, often multinucleated, cells in a background of small lymphocytes raised the possibility of HD.…”