Detection of mammary adenocarcinoma and metastasis with 99mTc-Thymine in a cat

Abstract

Mammary adenocarcinomas with metastasis are more common in dogs than in cats. Its incidence is 1 in every 4,000 cats. Usually, veterinary routine laboratory exams are nonspecific for these neoplasms and tumoral markers are not widely used in the practice. The clinical evaluation and image assessment leads the way to the proper treatment, especially when surgical intervention is a possibility. Although an invasive procedure, biopsy and histopathological findings are the gold standards which define the clinical approach. Procedures: This study describes the clinical signs, histopathological aspects, radiological and scintigraphic findings of a cat with mammary adenocarcinoma and metastasis evaluated one hour after intravenous administration of 99mTc-Thymine. Our focus is not to discuss the pathological aspects of the disease but the nuclear medicine role in metastasis detection. Metastasis when lesser than 4mm, could be unnoticed by radiological exams whereas scintigraphy may detect it. Results: Here, we successfully detected unsuspected metastasis in lungs, liver and right kidney. Early diagnosis is the key for a better rate of survival due to the given treatment and, prognostic. Conclusions: We strongly recommend the use of 99mTc-Thymine as a complementary tool for breast cancer diagnosis in veterinary care.