E-36. Long-term results after vertebral body resections for non-small cell lung cancer

Abstract

Introduction: Curative treatment of lung cancer involving the vertebral column remains one of the most difficult challenges for thoracic oncologists. Surgical treatment of lung carcinomas is still considered as the best means of local control, provided that a complete resection can be achieved. Ten years multidisciplinary experience of radical en bloc resection for lung tumors attached to the spine is reported. Data: Between 1993 and 2003, thirty-one patients underwent en bloc vertebral and lung resection for non-small cell lung carcinoma at 1’Institut Mutualiste Montsouris. In 26 of them, follow-up data longer than 6 months allowed late outcome analysis. Mean age of the patients was 47 years, ranging from 36 to 69. Histology of tumors was adenocarcinoma in a majority of the patients (62%). Criteria for en bloc resection were documented non-small cell lung cancer attached to the spine, without mediastinal lymph nodes or distant metastasis. Pathological tumor status was T4 and T3 in 58% (n= 15) and 42% (n= ll), respectively. Those T3 tumors required partial vertebrectomy in attempting to obtain free margins, although vertebral body was not actually involved. Nodal status was NO in a majority of the patients (77%). One unforeseen N2 involvement was discovered at operation, as well as ipsilateral supraclavicular nodes in two cases, contiguous to the tumor, that could be considered as resectable Nl nodes. Clinical stages were IIB in 9 patients (35%), IIIA in one, while 16 patients were in stage IIIB (62%). Sixteen patients received induction treatments: 10 were treated by induction chemotherapy (vinorelbine/cisplatin, 2 cycles); 4 patients received concomitant chemoradiotherapy (42 gray-bifractionated radiation therapy, concurrent cisplatin, 5 fluorouracil, and vinblastine, 2cycles); and 2 patients received only preoperative radiotherapy. Pulmonary resections were mainly lobectomies (77%). Vertebrectomy was partial and total in 21 and 5 cases, respectively. Mean number of resected vertebral bodies was 3 (1 to 4). The majority of patients were operated on by means of a 2-incision approach, using an osteomuscular sparing transmanubrial anterior access, followed by a midline posterior vertebral approach [l]. Through the anterior cervico-thoracic approach the tumor is separated from the vascular and nervous cervical structures, or vascular resections and reconstructions are performed. An en bloc lobectomy with nodal dissection is done, without opening the tumor block, thus respecting oncologic principles. The upper lobe is left attached to the vertebral column by the tumor involvement. After closure of the anterior approach, the patient is turned upside down in a prone position. Through a midline posterior approach, after laminectomy, stabilization of the spine, and spondylectomy the block is extracted by rotation about the cord [2]. Then the vertebral bodies are reconstructed using a bone graft. Vascular reconstruction was required in 2 cases. The number of resected ribs ranged from one to five. Five patients underwent total vertebrectomy, of T2 in one patient, T2 and T3 in three patients, and T4-5-6 in one patient. Mean operative time was 9 hours. Complete resection was achieved in 85% of the patients. No postoperative death occurred. But severe morbidity was observed in almost half the patients (46%). Five patients had to be reoperated on. Postoperative radiotherapy was given to 5 patients. Recurrences occurred in 20 patients, local in 31% (n = 8). Among the 22 completely resected patients, 6 had local relapses (27%). Two-year and 5-year survival rates were respectively 54% and 25% for the entire series, 60% and 21% for all T4 patients, and 73% and 30% for completely resected T4 patients. For these completely resected T4 patients, median survival was 25 months. Among the 16 IIIB patients, tumor was locally controlled at two years in 6 cases (38%). These results can be compared with those reported by the team of University of Texas MD Anderson Cancer Center, which observed an overall actuarial survival at 2 years of 54% [3]. On completely resected T4 patients (n = 11) median survival was found of 25 months. Disease-free-survival rates obtained at 2 years by this aggressive strategy compare favorably with the results achieved by non surgical treatments. In the same institution, Komaki and ~011. found a 15% local control rate at 2 years in Pancoast tumors with vertebral involvement [4]. Similarly, in a study by Arriagada and toll., radiation therapy with or without chemotherapy achieved a 2-year disease-free-survival inferior to 20% in stage IIIB inoperable non-small cell lung cancers [5]. In this series, 2-year disease-free-survival rate was 36% for patients with completely resected T4 tumors. Interestingly patients without recurrence at two years remain free of disease at 5 years. Conclusion: These results show that en bloc vertebral and lung resection are technically demanding procedures, and associated with a high rate of morbidity. Nevertheless the local control obtained is encouraging, and long term disease-free-survival can be achieved, even in the case of T4 invasion of the vertebral body by a non-small cell lung carcinoma.