Purpose: Superior sulcus tumors (SST) of the lung are uncommon and constitute approximately 3% of non-small cell lung cancer (NSCLC). These tumors cause specific symptoms and signs, and are associated with patterns of failure that differ from those seen for NSCLC tumors in other nonapical locations. Prognostic factors and most effective treatments are controversial. We conducted a retrospective study at The University of Texas M. D. Anderson Cancer Center to identify outcome predictors for patients with SST treated by a multidisciplinary approach.
Methods and materials: This retrospective review of 143 patients without distant metastasis at presentation is a continuation of a previous M. D. Anderson study now updated to 1994. In this study, we examine the 5-year survival rate by pretreatment tumor and patient characteristics and by the treatments received. Strict criteria were used to define SST. Actuarial life-table analyses and Cox proportional hazard models were used to compare survival rates.
Results: Overall predictors of 5-year survival were weight loss (p < 0.01), supraclavicular fossa (p = 0. 03), or vertebral body (p = 0.05) involvement, stage of the disease (p < 0.01), and surgical treatment (p < 0.01). Five-year survival for patients with Stage IIB disease was 47% compared to 14% for Stage IIIA, and 16% for Stage IIIB. For patients with Stage IIB disease, surgical treatment (p < 0.01) and weight loss (p = 0.01) were significant independent predictors of 5-year survival. Among patients with Stage IIIA disease, the only predictor of survival was Karnofsky performance score (KPS) (p = 0.02). For patients with Stage IIIB disease, the only independent predictor of survival was a right superior sulcus location, which was associated with a worse 5-year survival rate than that for patients with tumors in the left superior sulcus (p = 0.02). More patients with adenocarcinoma than with squamous cell tumors experienced cerebral metastases within 5 years (p < 0.01). Patients without gross residual disease after surgical resection who received postoperative radiation therapy with total doses of 55 to 64 Gy had a 5-year survival rate of 82% as compared with the 5-year survival rate of 56% in patients who received 50 to 54 Gy. Twenty-three patients survived for longer than 3 years. Of these, 4 patients (17%) received radiation therapy alone or in combination with chemotherapy without surgical resection. The other 19 patients (83%) had resection combined with radiation therapy and/or chemotherapy.
Conclusions: The findings from this study confirm the importance of the new staging system, separating T3 N0 M0 (Stage IIB) from Stage IIIA, since there was a significant difference in the 5-year survival (p < 0.01). Interestingly, there was no significant 5-year survival difference between Stage IIIA (N2) and Stage IIIB (T4 or N3). This study also suggests that surgery is an important component of the multidisciplinary approach to patients with SST if their nodes were negative. Disease that is minimally invading surrounding normal structures can be resected followed by radiation therapy in doses of 55 to 64 Gy. Further investigation of treatment strategies combining high-dose radiation therapy (>/=66 Gy) with chemotherapy is indicated for patients with unresectable and/or node-positive (N2) SST.