Tumor regression during radiotherapy as a predictor of response in locally advanced nonsmall cell carcinoma.

Aims: To compare the predicted response with observed response to treatment by measuring gross tumor volume-primary (GTVp) using onboard kilovoltage (kV) cone-beam computed tomography (CBCT), to analyze the serial tumor volumes during radiotherapy (RT) with serial tumor volumes during follow-up, and to identify the variables associated with survival outcomes. Materials and Methods: Between June 2017 and December 2019, 23 patients of histologically proven locally advanced nonsmall cell lung cancer (LA-NSCLC) received definitive chemoradiation. Serial kV-CBCT images X-ray volume imaging (XVI) were generated weekly for image guidance and were used to generate serial GTVp. Posttreatment follow-up images were used to generate follow-up GTVp. Relative volume regression (VR) during RT and relative response assessment (RA) during follow-up were defined from Avg Vol, of planning CT. The predicted progression model was generated from VR and analyzed against observed progression events. Regression-response model was generated to analyze VR against RA. Results: The median XVI vol1, XVI vol2, and XVI vol3 were 78.123, 56.571, and 48.513 cc during the 2nd, 4th, and 6th weeks of RT, respectively. The median VR0 was 11.777% in the 2nd-week, VR1 was 20.959% in the 4th week, and 33.661% in the 6th week. The predicted responders and progression using the VR were similar to the observed response during the follow-up. The prediction of both RA0 and RA1 obtained from VR2 was statistically significant. Predication of RA0 from VR1 tended towards significant (P=0.084). VR2 was statistically significant in predicting RA2 (P = 0.04). The median progression-free survival (PFS) was not reached and the median overall survival (OS) was 24.2 months (95% confidence interval, 20.3-28.2 months). There was no statistically significant difference in PFS and OS between Avg Vol ≤ 99.5 cc and > 99.5 cc or other clinical parameters. Conclusions: Tumor regression during RT is a potential predictor of response in LA-NSCLC. kV-CBCT is a strong tool in assessing tumor regression during RT.

Treatment outcomes and prognostic factors in locally advanced non-small cell lung cancer - An experience from normal India.

Context: Chemoradiation is the standard of care in locally advanced non-small cell lung cancer (LA-NSCLC). Clinical presentation, disease course, and available treatment options are challenges to overcome. Little is known about the ideal timing and interaction of the two modalities, its relevance in day-to-day decision-making and the treatment outcome. Aims: The study evaluates the demographic profile, treatment pattern, outcome, and radiotherapy (RT) practice and patient care of LA-NSCLC at a tertiary cancer center. Setting and Design: This is a retrospective study from a tertiary cancer centre. Archives of patients of LA-NSCLC treated between June 2016 and June 2018 were included in our study. Materials and Methods: Clinical, demographic characteristics, treatment patterns, and outcomes were recorded. RT practice and patient care process including the integration of RT with other specialties, waiting time, and compliance to treatment were documented and analyzed. Statistical Analysis: Overall survival (OS) and progression-free survival (PFS) were the primary endpoints of the study. Log-rank test was used for univariate analysis for the factors on OS, and Cox's proportional hazards model was used for multivariate analysis for cofactors on OS. Results: Two hundred and thirty-two patients of lung cancer were treated during the study period. Fifty-four patients were squamous cell carcinoma, 108 were adenocarcinoma, and 12 were others. Out of 59 patients of LA-NSCLC, 34 underwent definitive chemoradiation. The median follow-up was 11 months (0.7-29), median overall treatment time was 44 days, median PFS was 8.9 months (range: 1.6-28.6), and median OS was 9.4 months (1.7-44.8). Time to start any oncological intervention was 1 month (0.1-4.3) and time to start RT was 2.1 months (0.1-5.4). Adherence to treatment was 91.2%. Age ≥65 and performance status ≥2 were significant for OS on univariate analysis and none on multivariate analysis. Conclusions: One-third of the cases of NSCLC present in LA stage and a third are suitable for definitive chemoradiation and only 20% undergo the planned treatment.

High-dose-rate remote brachytherapy for metachronous second primary carcinoma of soft palate by iridium 192 isotope in an afterload surface mold.

Conservative management of metachronous second primary carcinoma of head and neck is preferred in order to preserve form and function. The purpose of the case report is to describe the treatment of metachronous second primary carcinoma of soft palate by high-dose-rate, remote, afterload brachytherapy. The brachytherapy was done in remote settings by afterloading Iridium 192 isotope carried through a custom fabricated surface mold. The mold enabled good adaptation, stability, and repeatable positioning of the radiation source at each treatment session of fractionated brachytherapy offering consistent dosimetric advantage through a single dosimetry calculation. Collaborative efforts of radiation oncologist and prosthodontist ensured conservative treatment in outpatient set up with minimal adverse effects.