Assessing failure patterns of radical intent radiation strategies in patients with locally advanced carcinoma of the esophagus.

BACKGROUND: Patterns of failure following definitive CRT (dCRT) are different as compared to neoadjuvant chemoradiotherapy (NACRT) with increased locoregional failures documented with dCRT. AIM: To document failure patterns in patients with esophageal carcinoma treated with neoadjuvant and definitive intent radiation strategies. METHODS: Subjects were 123 patients treated with two chemoradiotherapy strategies. Group 1 (n = 99) underwent dose escalated definitive chemoradiotherapy (dCRT), Group 2 (n = 24) received neoadjuvant chemoradiotherapy (NACRT) followed by surgery. Cumulative incidence of locoregional failure (LRF), local failure (LF), regional lymph node failure (RLNF), and distant metastasis (DM) were computed; differences between the groups was evaluated using log rank test. Univariable and multivariable predictors of failure were identified using Cox regression analysis. RESULTS: Cumulative LRF: 64% in Group 1 vs 35% in Group 2 (P = .050). Cumulative LF: 59% in Group 1 vs 12% in Group 2 (P = .000). Cumulative RLNF: 30% in Group 1 vs 24% in Group 2 (P = .592). Most common RLNF: mediastinum for both groups (6% vs 12.5%, respectively). Distant metastasis: 40.4% Group 1 vs 17% Group 2 (P = .129), predominantly lung (Group 1, 5%), and nonregional nodes (Group 2, 8.3%). Univariate analysis identified age ≤50, absence of concurrent chemotherapy, dose ≤50 Gy, and incomplete radiotherapy to predict higher odds of LRF and DM for Group 1; absence of comorbidities predicted for lower odds of LRF for Group 2. Age ≤50 predicted for higher odds of RNLR for Group 1, while absence of comorbidities predicted for lower odds of RNLR in Group 2. Multivariate analysis identified age ≤50, incomplete radiotherapy, and absence of concurrent chemotherapy to predict higher odds of LRF for Group 1. Age ≤50, absence of concurrent chemotherapy predicted higher odds of DM for Group 1. Absence of comorbidity predicted lower odds of LRF in Group 2. CONCLUSION: LRF is common in both groups, with LF being predominant in dCRT as opposed to RNLF in NACRT. Age ≤50, absence of concurrent chemotherapy is a predictor of LRF and DM in dCRT.

Total reference air kerma: to what extent can it predict intracavitary volume enclosed by isodose surfaces during multiple high-dose rate brachytherapy?

BACKGROUND: The International Commission on Radiation Units and Measurements (ICRU) report 38 recommends reporting of total reference air kerma (TRAK) and reference ICRU isodose volumes during intracavitary brachytherapy (ICBT) in cancer of the cervix. The present study attempts to estimate the volumes enclosed by isodose surfaces from TRAK and evaluate its utility to represent doses to organs of interest. MATERIAL AND METHODS: Volumes encompassed by isodose surfaces of 3 Gy, 6 Gy, 9 Gy, and 12 Gy were obtained for 90 high-dose rate (HDR) ICBT procedures. These were used to derive a relation between isodose volumes, TRAK/dose (K/D), and rectal and bladder doses. RESULTS: Actual volumes (V) encompassed by isodose surfaces were reflected as a quadratic function of K/D (r(2)=0.998) and the expression, V=-23.09+1295.99(K/D)+5661.65(K/D)(2) gave the best estimates for various volumes. No correlation was observed between TRAK and bladder (r(2)=0.086) or rectal doses (r(2)=0.082). CONCLUSIONS: Estimates of volumes encompassed by different dose levels from TRAK could be derived with reasonable certainty. However, TRAK fails to correlate with rectal and bladder doses.

Safety and efficacy of concurrent cisplatin and radiotherapy in inoperable or metastatic squamous cell esophageal cancer.

Between August 1996 and May 1999, 50 consecutive, previously untreated patients with carcinoma of the esophagus and who were inoperable for various reasons were treated with weekly doses of cisplatin (35 mg/m2, maximum 7 cycles) concurrent with either 66 Gy/33 fractions external beam radiotherapy (EBRT) (n = 42) or 50 Gy/25 fractions EBRT and two insertions of high-dose-rate intraluminal radiotherapy of 6 Gy each, spaced a week apart (n = 8). Eighty-two percent (41/50) of the patients received the stipulated radiotherapy (RT) dose. Seventy-six percent (38/50) received at least 6 cycles of chemotherapy. Neutropenia in the form of WHO grade 11-12%, (6/50) and grade III-2% (1/50) was observed. Grade III emesis was seen in 8% (4/50). Improvement in the swallowing status was seen in 84% (42/50). Median duration of dysphagia relief was 6 months. The median overall survival was 9 months with 17% estimated to be alive after 4 years. Combined treatment with single agent cisplatin and definitive radiotherapy for inoperable cancer of the esophagus is safe, well tolerated and reasonably efficacious.