Multifocal cutaneous non-epitheliotropic B-cell lymphoma in a cat

Abstract

Case summary Skin tumours are the second-most common form of feline cancer after haematopoietic neoplasms and are often malignant. Cutaneous lymphoma is uncommon in cats and can be classified as epitheliotropic (typically of T-cell origin) or non-epitheliotropic (either of T-cell or B-cell origin). The present study describes a case of multifocal cutaneous non-epitheliotropic B-cell lymphoma. The skin nodules were multiple and variable in size; showed rapid progression; were alopecic and erythematous in appearance and pruritic and ulcerated; and were mostly located on the trunk. Nodule biopsies revealed the presence of uniform medium-to-large round neoplastic cells that infiltrated the dermis and subcutis. The neoplasias were consistent with a round cell cutaneous tumour and did not show evidence of epitheliotropism. Furthermore, immunohistochemical assessments indicated an immunophenotype characterised by round cells with a strong membrane and cytoplasmic positivity for the CD20 antigen, consistent with a lymphocyte of B-cell origin. Relevance and novel information Cutaneous non-epitheliotropic B-cell lymphoma in cats is rare and was previously reported to appear as single dermal and subcutaneous masses that are variable in size and generally develop in the tarsal region. To our knowledge, this is the first report to describe multifocal cutaneous non-epitheliotropic B-cell lymphoma in a cat.

Non-epitheliotropic Cutaneous T-cell lymphoma in a cat: a case report

“…The epitheliotropic and non-epitheliotropic forms can have similar clinical appearances. The lesions may be solitary or diffuse and are often described by various manifestations such as erythematous spots, alopecia, scales, skin nodules, or ulcerative plaques [5,7]. The period of existence of the lesion before diagnosis varies from case to case: the lesions can last up to 2 years in NECL [10], and the lesion progressed rapidly and worsened within 2 months in this case.…”

“…Most epitheliotropic tumors are of T-cell origin, and the tumor cells infiltrate the epidermis and adnexal epithelium in ECL [3]; however, tumor cells are of either T-cell or B-cell origin and do not usually involve the adnexal gland in NECL [4]. Previous studies have reported that the prognosis of NECL is grave, and its median survival time appears to be shorter than that of ECL [3,5]. Herein, we report a case to describe clinical and pathological findings of T-cell NECL in a cat.…”

“…Cutaneous lymphoma is rarely reported and constitutes 0.2% to 3.0% of the feline lymphomas [6]. ECL is characterized by T cells with an affinity for the epidermis and adnexal epithelium, whereas NECL is of B-or T-cell origin and is characterized by neoplastic lymphocytes predominantly in the dermis and subcutis [1,5,7]. Although it is known that NECL is more common in feline cutaneous lymphoma [7], but most documents are ECL in cats [4,8] thopedic implants, and viral infection have been suggested to be risk factors for its development [5,6].…”

“…ECL is characterized by T cells with an affinity for the epidermis and adnexal epithelium, whereas NECL is of B-or T-cell origin and is characterized by neoplastic lymphocytes predominantly in the dermis and subcutis [1,5,7]. Although it is known that NECL is more common in feline cutaneous lymphoma [7], but most documents are ECL in cats [4,8] thopedic implants, and viral infection have been suggested to be risk factors for its development [5,6]. Recently, the following feline NECL subgroups have been acknowledged: cutaneous lymphoma at injection sites [9], tarsal lymphoma [1], and NECL associated with a fracture site [6].…”

Subcutaneous panniculitis‐like T‐cell lymphoma: Morphological, immunophenotypical and clonality assessment in six cats

“…11 Primary cutaneous lymphomas account for 0.2%-3% of all feline lymphomas, with nonepitheliotropic lymphomas reported more frequently than epitheliotropic forms. [12][13][14] Primary nonepitheliotropic cutaneous lymphomas reported in cats comprise indolent T-cell lymphoma, also referred to as cutaneous lymphocytosis, 15 multifocal cutaneous B-cell lymphoma, 16 T-cell-rich B-cell lymphoma, 12,17 and injection site lymphoma. 18 Thus, because of the lack of documentation, we believe that this study represents the first documentation of SPTCL in cats presenting features that resemble the human and canine forms of the disease.…”