The case was a 2.5-year-old calico cat with an abdominal mass, which was brought from a private clinic to Ankara University, Veterinary Faculty, Animal Hospital, Internal Diseases Clinic. It was reported that the cat was operated 20 days ago, a mass of 8 cm in diameter near the jejunum was removed, but a second mass in the region was noticed in the investigation. The mass removed with operation was found to be Lymphoblastic lymphocarcinoma. In the ultrasonography, a two lobed mass of 3x4.5 cm in size was detected in the mesenterium near the liver. An alternative treatment was considered to be performed instead of reoperation on determining that the mass recurred in a very short time and was malignant as a result of the pathology. Considering that the cat was young and with good general condition, it was decided to administer chemotherapy. Modified Wisconsin Maddison method was selected for the chemotherapy. Shortly after the initiation of the chemotherapy protocol, chemotherapy had to be discontinued due to dense acid accumulation in the abdomen and deterioration of the general condition. Feline Corona Virus was detected positive in the cat scanned for subclinical diseases.