Small Cell Lung Cancer 小细胞肺癌
NCCN Guidelines Version 2.2017
Surgical Resection of Stage I SCLC
The Principles of Surgical Resection for SCLC are described in the NCCN algorithm; studies supporting these recommendations are described in this section. Briefly, the NCCN Guidelines state that surgery should only be considered for patients with stage I (T1–2, N0) SCLC in whom mediastinal staging has confirmed that mediastinal lymph nodes are not involved. Data show that patients with clinically staged disease in excess of T1–2,N0 do not benefit from surgery. Note that only 5% of patients with SCLC have true stage I SCLC. The Lung Cancer Study Group conducted the only prospective randomized trial evaluating the role of surgery in SCLC. Patients with limited-stage disease, excluding those with solitary peripheral nodules, received 5 cycles of chemotherapy with CAV; those showing a response to chemotherapy were randomly assigned to undergo resection plus thoracic radiotherapy or thoracic radiotherapy alone. The overall survival rates of patients on the 2 arms were equivalent, suggesting no benefit to surgery in this setting. However, only 19% of enrolled patients had clinical stage I (T1–2, N0, M0) disease.
Most data regarding the benefit of surgery are from retrospective reviews. These studies report favorable 5-year survival rates of 40% to 60% in patients with stage I disease. In most series, survival rates decline significantly in patients with more advanced disease, leading to the general recommendation that surgery should only be considered in those with stage I disease. Interpretation of these results is limited by the selection bias inherent in retrospective reviews and by the variable use of chemotherapy and radiotherapy.
Analyses of the SEER database also suggest that surgery may be appropriate for some patients with localized disease. However, these studies are limited by the lack of information on chemotherapy use in the database. In addition, comparison of the survival of surgical patients to all those who did not undergo surgery is inherently flawed by selection bias. Ultimately, the role of surgery in SCLC will not be fully defined until results are available from trials comparing surgery plus adjuvant chemotherapy to concurrent chemoradiotherapy in patients who are rigorously staged.
In all patients with clinical stage I (T1–2, N0) SCLC who are being considered for surgical resection, occult nodal disease should be ruled out through mediastinal staging before resection. If resection is performed, the NCCN Panel favors lobectomy and does not feel that segmental or wedge resections are appropriate for patients with SCLC. After complete resection, adjuvant chemotherapy or chemoradiation is recommended. Adjuvant chemotherapy alone is recommended for patients without nodal metastases, whereas concurrent chemotherapy and postoperative mediastinal radiotherapy are recommended for patients with nodal metastases (see Adjuvant Treatment in the NCCN Guidelines for SCLC). Although panel members agree that postoperative mediastinal radiotherapy is recommended in this setting, it should be based on the extent of nodal sampling/dissection and extent of nodal positivity; however, there are no data to support this recommendation. PCI should be considered after adjuvant therapy in select patients, because it can improve survival (see Prophylactic Cranial Irradiation in this Discussion and Adjuvant Treatment in the NCCN Guidelines for SCLC). For the 2017 update, the NCCN Panel added new recommendations for response assessment after adjuvant therapy. Response assessment using CT with contrast of the chest, liver, and adrenal gland should occur only after completion of initial therapy for patients with limited-stage disease; repeating scans during therapy is not recommended.