Study objective: To determine the indications for preoperative localization of a small indeterminate pulmonary nodule.
Design: In this retrospective study, univariate and multivariate analyses were performed by the logistic regression procedure.
Setting: A single National Cancer Center Hospital in Japan.
Patients: A series of 92 consecutive patients who underwent video-assisted thoracoscopic surgery (VATS) at our institute between 1993 and 1996.
Interventions: The frequency and reasons for conversion to thoracotomy were assessed retrospectively. All preoperative CT scans were reviewed for eight radiologic features by two of the authors. These data were entered into univariate and multivariate analyses to identify the significant risk factors for a failure to detect a pulmonary nodule.
Measurements and results: Fifty patients (54%) needed conversion to a thoracotomy. The most common reason for the conversion was failure to localize nodules (46%). Univariate and multivariate analyses of 11 variables revealed one significant risk factor in the failure to detect nodules: distance to the nearest pleural surface (p < 0.05). Tumor size on radiograph remained marginally significant (p = 0.065) in multivariate analyses. If the distance to the pleural surface was > 5 mm in cases of nodules < or = 10 mm in size, the probability of failure to detect a nodule was 63%.
Conclusions: Our results suggested the indications for preoperative localization of a peripheral pulmonary nodule. Preoperative marking for a small indeterminate pulmonary nodule should be considered when the distance to the nearest pleural surface is > 5 mm in cases of lung nodules of < or = 10 mm in size.