Primary vaginal T-cell lymphoma involving the cervix in 2 dogs

This report describes 2 cases of extremely rare primary vaginal T-cell lymphoma involving the cervix in dogs, diagnosed through comprehensive imaging, histopathological, and immunophenotypic evaluations. Case 1 involved a 12-year-old spayed female Shiba Inu dog that was presented with dyschezia and vulvar bleeding. Cytologic evaluation of fine-needle aspirates was nondiagnostic, necessitating tissue biopsy for definitive diagnosis. Computed tomography revealed a large vaginal mass with poor contrast enhancement and a uniformly hypodense internal structure. Chemotherapy with prednisolone, L-asparaginase, and lomustine resulted in temporary tumor regression; however, disease progression was noted by Day 50, and the dog died on Day 56. Case 2 involved a 10-year-old spayed female mixed-breed dog that was presented with dyschezia, dysuria, and hematuria. A CT scan revealed a large mass extending from the vaginal canal into the pelvic cavity. Cytologic evaluation was inconclusive. Surgical excision of the mass and urinary diversion was done, followed by chemotherapy with L-asparaginase, prednisolone, and lomustine. Despite these interventions, the clinical condition rapidly deteriorated, and the dog died on Day 44. Necropsy revealed widespread systemic dissemination of lymphoma and findings consistent with disseminated intravascular coagulation. These cases highlight the aggressive clinical behavior of this disease and underscore the importance of early histopathological diagnosis for appropriate therapeutic intervention. Key clinical message: Lymphoma should be considered as a differential diagnosis in dogs with primary vaginal masses.