肺葉切除後に肺内転移が認められた犬に対し外科切除および補助的化学療法を行った1例

抄録

A 9-year-old neutered female Miniature Dachshund had undergone lobectomy of the left frontal lobe for lung carcinoma followed by nine post-operative doses of carboplatin chemotherapy(250 mg/m², every 3weeks). The dog was referred to the Japan Animal Referral Medical Center (Nagoya), because of lung masses in the opposite right middle and posterior lobes. Whole body contrast-enhanced computed tomography(CT)was performed and revealed lung solitary tumors in the relevant areas. No abnormal findings were observed in other lobes or intrathoracic lymph nodes. Since the possibility of metastatic lesions of lung carcinoma incompletely removed in the previous surgery was considered, we performed CT again on day 45 for evaluation of the new tumor progression. The size of both tumors increased, and right middle and posterior lung lobectomies were carried out on day 53. There were no adhesive lesions around the tumors, carcinomatous pleuritis, pleural fluid or hilar lymphadenopathy. While histopathology revealed high-grade lung adenocarcinoma with numerous mitoses, there was no evidence of intravascular invasion, suggesting complete resection. A tentative diagnosis of metastatic lung tumor(T2N0M1)was made. Adjuvant chemotherapy with carboplatin(250 mg/m², for every 3 weeks)and piroxicam(0.3 mg/kg/3 days)was also given starting on day 21, and no evidence of recurrent lesions was observed on day 726 with a good health condition maintained. From these results, it is suggested that aggressive surgery plus adjuvant chemotherapy can be appropriate treatments for metastatic lung carcinoma.