Impact of primary tumour stage on survival in dogs with solitary lung tumours.
OBJECTIVE
The objective of this study was to determine simple prognostic criteria for differentiation of canine solitary lung tumour cases into those that will and will not benefit from thoracic surgery.


METHODS
This was a retrospective study using the records of cases presented to Davies Veterinary Specialists, Hitchin, UK, from December 1998 to December 2005. Survival analyses were performed using the Kaplan-Meier and logrank methods. Potentially significant variables were evaluated by multivariate Cox analysis.


RESULTS
Forty-two patients met the inclusion criteria. Primary tumour stage T1, absence of neoplastic lymph nodes and metastases, and papillary tumour type were statistically significant favourable prognostic indicators on univariate analysis. Multivariate analysis attributed significance to primary tumour stage T1 and papillary type only. Median survival times were 555 days for T1N0M0 tumours of papillary type and 72 days for the remainder.


CONCLUSIONS
Survival time following surgery in dogs with primary lung tumours was poor except in clinical stage T1N0M0 cases. These data support use of clinical techniques to dichotomise cases as T1N0M0 or other, improving decision making in thoracic surgery. These data validate initiation of prospective studies examining the role of chemotherapy in the management of advanced cases.
Polton
G A
GA
Davies Veterinary Specialists, Manor Farm, Business Park, Higham Gobion, Hitchin, Hertfordshire SG5 3HR, UK.
Brearley
M J
MJ
Powell
S M
SM
Burton
C A
CA
D000818:Animals; D003657:Decision Making; D004283:Dog Diseases / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D004285:Dogs; D005260:Female; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000473:pathology / Q000601:surgery; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D008297:Male; D015999:Multivariate Analysis; D009367:Neoplasm Staging / Q000662:veterinary*; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome