Research Update: Thoracoscopy: A viable treatment of lung tumors in dogs

In this retrospective study from a veterinary teaching hospital, nine dogs with lung tumors were treated with thoracoscopic lung lobectomy. The dogs' mean weight was 63.8 lb (29 kg) and mean age was 10.7 years. Six dogs had a previous neoplastic disease.

The preoperative diagnosis was metastatic lung disease in six dogs and a primary lung tumor in three dogs. The diagnoses were based on the dogs' histories and the results of thoracic radiography. Fluoroscopy, scintigraphy, fine-needle aspiration and cytology, or bronchoalveolar lavage cytology were also used in some dogs. In six dogs, a solitary mass was identified; the other three dogs had at least two masses in the same lung lobe.

The mean duration of surgery was 109 minutes for dogs undergoing thoracoscopy only and 151 minutes for the four dogs having thoracoscopy followed by thoracotomy. In these patients, poor visibility necessitated the second procedure. A chest tube was placed in all the dogs before they recovered from anesthesia, and the chest tubes remained in place for a mean duration of 24 hours. Various analgesics (fentanyl, lidocaine, bupivacaine, piroxicam) were administered postoperatively. Complications included intercostal artery hemorrhage (1), thrombocytopenia and hyperthermia (1), corneal ulceration (1), subcutaneous emphysema (1), aspiration pneumonia (1), and poor oxygenation (2).

The dogs remained in the hospital for a mean duration of 3.1 days. The owners of five of the dogs were contacted by telephone and reported a mean survival time of 1.3 years. In spite of the small sample size, the authors concluded that thoracoscopy was useful in treating small lung tumors located away from the hilus.

COMMENTARY

Although primary lung tumors are rare and metastatic lesions represent advanced disease, surgically resecting these masses prolongs patients' survival times. In people, therapeutic thoracoscopy greatly reduces patient morbidity compared with thoracotomy. With this in mind, along with reports of other thoracoscopic procedures in animals, the authors pursued thoracoscopic lung lobectomy for tumor removal in dogs. The results of this study support the usefulness of the procedure, and with increasing data and experience, the advantages (vs. thoracotomy) and technical ease of the procedure will become more apparent.

Lansdowne JL, Monnet E, Twedt DC, et al. Thoracoscopic lung lobectomy for treatment of lung tumors in dogs. Vet Surg 2005;34:530-535.

The information in "Research Updates" was provided by Veterinary Medicine Editorial Advisory Board member Joseph Harari, MS, DVM, DACVS, Veterinary Surgical Specialists, 21 E. Mission Ave., Spokane, WA 99202.

Joseph Harari, MS, DVM, DACVS