Selective nodal irradiation on basis of (18)FDG-PET scans in limited-disease small-cell lung cancer: a prospective study.
ABSTRACT To evaluate the results of selective nodal irradiation on basis of (18)F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure.
A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter.
A difference was seen in the involved nodal stations between the pretreatment (18)F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis.
PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.
- [show abstract] [hide abstract]
ABSTRACT: Thoracic radiotherapy provides a survival benefit in patients with limited-stage disease of small cell lung cancer (LS-SCLC), but inclusion and exclusion of prophylactic irradiation of the supraclavicular area are still controversial. This study analyses the risk factors and characteristics of lymph node metastases in the supraclavicular area of LS-SCLC patients, which could help in developing a better radiotherapy for the patients. A total of 239 patients with LS-SCLC were included in this retrospective analysis. Clinical characteristics and mediastinal lymph node metastasis were analyzed for association with SCM, and the SCM pattern was further analyzed based on the treatment planning CT scans. The SCM incidence was 34.7 % (83 of 239). The multivariate analysis showed that only the mediastinal level 2 (OR = 16.101, P = 0.000) and level 3 (OR = 5.597, P = 0.000) lymph node metastases were significantly associated with SCM. As the most frequently involved region, supraclavicular level I lymph node metastases were identified in 61 of 83 patients (73.5 %), followed by level III, level IV, level V, and level II lymph node metastases, accounting a total of 95.2 % for level I and/or III lymph node metastases, whereas the incidence of skip metastasis was only 4.8 %. SCLC patients with mediastinal level 2 and level 3 lymph node metastasis were at high risk of SCM. If prophylactic irradiation therapy is considered, the nodal clinical target volume of irradiation should include bilateral lower para-recurrent laryngeal neural region (level I) and the para-internal jugular venous region (level III).Medical Oncology 03/2013; 30(1):493. · 2.14 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: The optimal timing of chemoradiotherapy in limited-stage small-cell lung cancer (LS-SCLC) hasn't been established, although evidence from studies supported that patients can benefit from early radiation therapy. The purpose of this study was to quantify tumor shrinkage in response to induction chemotherapy (IC), evaluate the impact of tumor shrinkage on radiation dosimetric parameters and determine its implication for the timing of radiation therapy for patients with LS-SCLC. Twenty patients with LS-SCLC who were treated with IC followed by concomitant radiation therapy were investigated retrospectively. Ten patients received 1 cycle of IC, and 10 patients received 2 cycles of IC. Pre-IC CT imaging was coregistered with a simulation CT, and virtual radiation plans were created for pre- and post-IC thoracic disease in each case. The changes in the gross target volume (GTV), planning target volume (PTV) and dosimetric factors associated with the lungs, esophagus and heart were analyzed. The mean GTV and PTV for all of the patients decreased by 60.9% and 40.2%, respectively, which resulted in a significant reduction in the radiation exposure to the lungs, esophagus and heart. Changes in the PTV and radiation exposure of normal tissue were not significantly affected by the number of chemotherapy cycles delivered, although patients who received 2 cycles of IC had a greater decrease in GTV than those who received only 1 cycle of IC (69.6% vs. 52.1%, p = 0.273). Our data showed that targeting the tumor post-IC may reduce the radiation dose to normal tissue in patients with LS-SCLC. However, the benefit to the normal tissue was not increased by an additional cycle of IC. These findings suggest that the first cycle of chemotherapy is very important for tumor shrinkage and that initiating thoracic radiation therapy at the second cycle of chemotherapy may be a reasonable strategy for timing of radiation therapy in LS-SCLC treatment.Radiation Oncology 09/2013; 8(1):216. · 2.11 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Radiotherapy (RT) is fundamental to the care of patients diagnosed with small-cell lung cancer (SCLC). In the setting of limited stage disease (LS-SCLC), the addition of thoracic RT to chemotherapy (CHT) improves survival and local control, as demonstrated in decades-worth of randomized clinical trials and subsequent meta-analyses. In extensive stage disease (ES-SCLC), thoracic RT is invaluable in the palliation of chest symptoms but there are suggestions that its use in selected patients may potentially improve overall survival . Prophylactic cranial irradiation (PCI) also improves outcomes in SCLC. For LS-SCLC patients, it reduces brain metastases rates by half and improves overall survival with minimal impact on quality-of-life. Recently, favorable results for PCI with respect to survival and prevention of symptomatic brain disease have been observed for ES-SCLC patients with any response to CHT. Current phase III trials in SCLC RT include studies looking at the optimal dose and target for limited disease and the role of thoracic RT in extensive disease.Current Oncology Reports 04/2013; · 3.33 Impact Factor