The morphologic spectrum of primary cutaneous anaplastic large T-cell lymphoma: a histopathologic study on 66 biopsy specimens from 47 patients with report of rare variants.
BACKGROUND
Primary cutaneous anaplastic large T-cell lymphoma (PCALCL) is a well-defined entity with prognostic differences from the nodal counterpart [nodal anaplastic large cell lymphoma (NALCL)]. Several histological variants of NALCL have been characterized (common, lymphohistiocytic and small cell). However, studies on morphological variants of PCALCLs are lacking.


METHODS
We analyzed retrospectively the clinicopathologic features of 66 biopsies from 47 patients (M : F = 27 : 20; median age: 53 years; mean age: 51.8 years; range: 14-82) with PCALCL, in order to better characterize the spectrum of this unusual neoplasm.


RESULTS
The 'common variant' was the most frequent (40.4%). In contrast to NALCL, in PCALCL, marked reactive infiltrates are more commonly present. In fact, 26 cases were classified as 'inflammatory type' (15 cases) and 'lymphohistiocytic' (11 cases). Concerning the predominant cell morphology, large anaplastic cells (33%) were almost as frequent as large pleomorphic (36%) and small to medium-sized cells (26%). We reported for the first time in the skin 2 rare cases with the predominance of large cells with a 'signet-ring'-like appearance. Epidermotropism and presence of eosinophils were found in a proportion of cases in all PCALCL variants.


CONCLUSIONS
PCALCL is characterized by variable histopathological presentations and a broad cytomorphologic spectrum.
Massone
Cesare
C
Department of Dermatology, Research Unit of Dermatopathology, Medical University of Graz, Graz, Austria.
El-Shabrawi-Caelen
Laila
L
Kerl
Helmut
H
Cerroni
Lorenzo
L
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D004804:Eosinophils / Q000473:pathology; D005260:Female; D015329:Gene Rearrangement, T-Lymphocyte / Q000235:genetics; D006801:Humans; D007124:Immunoenzyme Techniques; D016130:Immunophenotyping; D054446:Lymphoma, Primary Cutaneous Anaplastic Large Cell / Q000737:chemistry / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology*
D014408:Biomarkers, Tumor