Page 202 - Differential Diagnosis in Small Animal Cytology, The Skin and Subcutis

Round Cell Tumours
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Pearls and Pitfalls
VetBooks.ir • Definitive diagnosis of cutaneous lymphoma may require additional testing, including
histopathology ideally accompanied by immunophenotypical techniques (immunohisto-
chemistry, flow cytometry) and/or clonality assay (PARR – PCR for antigen receptor
rearrangement). This is particularly useful in the small cell forms, which may appear undis-
tinguishable from lymphocytic inflammation.
• Cutaneous lymphoma can also be the manifestation of a generalized form of lymphoma.

(A) (B)

(C)

Fig. 10.19. Schematic representation of the distribution of neoplastic lymphoid cells in (A) cutaneous epithelio-
tropic lymphoma, (B) cutaneous non-epitheliotropic lymphoma and (C) subcutaneous lymphoma.