Jonathan B. Ashman

Reduced acute bowel toxicity in patients treated with intensity-modulated radiotherapy for rectal cancer.

PURPOSE We have previously shown that intensity-modulated radiotherapy (IMRT) can reduce dose to small bowel, bladder, and bone marrow compared with three-field conventional radiotherapy (CRT) technique in the treatment of rectal cancer. The purpose of this study was to review our experience using IMRT to treat rectal cancer and report patient clinical outcomes. METHODS AND MATERIALS A retrospective review was conducted of patients with rectal cancer who were treated at Mayo Clinic Arizona with pelvic radiotherapy (RT). Data regarding patient and tumor characteristics, treatment, acute toxicity according to the Common Terminology Criteria for Adverse Events v 3.0, tumor response, and perioperative morbidity were collected. RESULTS From 2004 to August 2009, 92 consecutive patients were treated. Sixty-one (66%) patients were treated with CRT, and 31 (34%) patients were treated with IMRT. All but 2 patients received concurrent chemotherapy. There was no significant difference in median dose (50.4 Gy, CRT; 50 Gy, IMRT), preoperative vs. postoperative treatment, type of concurrent chemotherapy, or history of previous pelvic RT between the CRT and IMRT patient groups. Patients who received IMRT had significantly less gastrointestinal (GI) toxicity. Sixty-two percent of patients undergoing CRT experienced ≥Grade 2 acute GI side effects, compared with 32% among IMRT patients (p = 0.006). The reduction in overall GI toxicity was attributable to fewer symptoms from the lower GI tract. Among CRT patients, ≥Grade 2 diarrhea and enteritis was experienced among 48% and 30% of patients, respectively, compared with 23% (p = 0.02) and 10% (p = 0.015) among IMRT patients. There was no significant difference in hematologic or genitourinary acute toxicity between groups. In addition, pathologic complete response rates and postoperative morbidity between treatment groups did not differ significantly. CONCLUSIONS In the management of rectal cancer, IMRT is associated with a clinically significant reduction in lower GI toxicity compared with CRT. Further study is needed to evaluate differences in late toxicity and long-term efficacy.

Postoperative stereotactic radiosurgery compared with whole brain radiotherapy for resected metastatic brain disease (NCCTG N107C/CEC·3): a multicentre, randomised, controlled, phase 3 trial

BACKGROUND Whole brain radiotherapy (WBRT) is the standard of care to improve intracranial control following resection of brain metastasis. However, stereotactic radiosurgery (SRS) to the surgical cavity is widely used in an attempt to reduce cognitive toxicity, despite the absence of high-level comparative data substantiating efficacy in the postoperative setting. We aimed to establish the effect of SRS on survival and cognitive outcomes compared with WBRT in patients with resected brain metastasis. METHODS In this randomised, controlled, phase 3 trial, adult patients (aged 18 years or older) from 48 institutions in the USA and Canada with one resected brain metastasis and a resection cavity less than 5·0 cm in maximal extent were randomly assigned (1:1) to either postoperative SRS (12-20 Gy single fraction with dose determined by surgical cavity volume) or WBRT (30 Gy in ten daily fractions or 37·5 Gy in 15 daily fractions of 2·5 Gy; fractionation schedule predetermined for all patients at treating centre). We randomised patients using a dynamic allocation strategy with stratification factors of age, duration of extracranial disease control, number of brain metastases, histology, maximal resection cavity diameter, and treatment centre. Patients and investigators were not masked to treatment allocation. The co-primary endpoints were cognitive-deterioration-free survival and overall survival, and analyses were done by intention to treat. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT01372774. FINDINGS Between Nov 10, 2011, and Nov 16, 2015, 194 patients were enrolled and randomly assigned to SRS (98 patients) or WBRT (96 patients). Median follow-up was 11·1 months (IQR 5·1-18·0). Cognitive-deterioration-free survival was longer in patients assigned to SRS (median 3·7 months [95% CI 3·45-5·06], 93 events) than in patients assigned to WBRT (median 3·0 months [2·86-3·25], 93 events; hazard ratio [HR] 0·47 [95% CI 0·35-0·63]; p<0·0001), and cognitive deterioration at 6 months was less frequent in patients who received SRS than those who received WBRT (28 [52%] of 54 evaluable patients assigned to SRS vs 41 [85%] of 48 evaluable patients assigned to WBRT; difference -33·6% [95% CI -45·3 to -21·8], p<0·00031). Median overall survival was 12·2 months (95% CI 9·7-16·0, 69 deaths) for SRS and 11·6 months (9·9-18·0, 67 deaths) for WBRT (HR 1·07 [95% CI 0·76-1·50]; p=0·70). The most common grade 3 or 4 adverse events reported with a relative frequency greater than 4% were hearing impairment (three [3%] of 93 patients in the SRS group vs eight [9%] of 92 patients in the WBRT group) and cognitive disturbance (three [3%] vs five [5%]). There were no treatment-related deaths. INTERPRETATION Decline in cognitive function was more frequent with WBRT than with SRS and there was no difference in overall survival between the treatment groups. After resection of a brain metastasis, SRS radiosurgery should be considered one of the standards of care as a less toxic alternative to WBRT for this patient population. FUNDING National Cancer Institute.

Excellent local control with preoperative radiation therapy, surgical resection, and intra-operative electron radiation therapy for retroperitoneal sarcoma

To examine the value of surgical resection combined with preoperative external beam radiation therapy and intraoperative radiation therapy (Surg‐RT) for retroperitoneal sarcoma (RPS).

Neoadjuvant chemoradiation compared to neoadjuvant radiation alone and surgery alone for Stage II and III soft tissue sarcoma of the extremities.

BackgroundNeoadjuvant chemoradiation (NCR) prior to resection of extremity soft tissue sarcoma (STS) has been studied, but data are limited. We present outcomes with NCR using a variety of chemotherapy regimens compared to neoadjuvant radiation without chemotherapy (NR) and surgery alone (SA).MethodsWe conducted a retrospective chart review of 112 cases.ResultsTreatments included SA (36 patients), NCR (39 patients), and NR (37 patients). NCR did not improve the rate of margin-negative resections over SA or NR. Loco-regional relapse-free survival, distant metastases-free survival, and overall survival (OS) were not different among the treatment groups. Patients with relapsed disease (OR 11.6; p = 0.01), and tumor size greater than 5 cm (OR 9.4; p = 0.01) were more likely to have a loco-regional recurrence on logistic regression analysis. Significantly increased OS was found among NCR-treated patients with tumors greater than 5 cm compared to SA (3 year OS 69 vs. 40%; p = 0.03). Wound complication rates were higher after NCR compared to SA (50 vs. 11%; p = 0.003) but not compared to NR (p = 0.36). Wet desquamation was the most common adverse event of NCR.ConclusionsNCR and NR are acceptable strategies for patients with STS. NCR is well-tolerated, but not clearly superior to NR.

Compliance with National Comprehensive Cancer Network guidelines in the use of radiation therapy for extremity and superficial trunk soft tissue sarcoma in the United States.

We sought to examine adherence to National Comprehensive Cancer Network guidelines for use of radiation therapy (RT) in patients with soft tissue sarcoma (STS) in the United States.

Prophylactic cranial irradiation in elderly patients with small cell lung cancer: Findings from a North Central Cancer Treatment Group pooled analysis

OBJECTIVES To examine the efficacy of prophylactic cranial irradiation (PCI) in elderly patients with small cell lung cancer (SCLC) (≥70 years of age) from a pooled analysis of four prospective trials. MATERIALS & METHODS One hundred fifty-five patients with SCLC (limited stage, LSCLC, and extensive stage, ESCLC) participated in four phase II or III trials. Ninety-one patients received PCI (30 Gy/15 or 25 Gy/10) and 64 patients did not receive PCI. Survival was compared in a landmark analysis that included only patients who had stable disease or better in response to primary therapy. RESULTS Patients who received PCI had better survival than patients who did not receive PCI (median survival 12.0 months vs. 7.6 months, 3-year overall survival 13.2% vs. 3.1%, HR = 0.53 [95% CI 0.36-0.78], p = 0.001). On multivariate analysis of the entire cohort, the only factor that remained significant for survival was stage (ESCLC vs. LSCLC, p = 0.0072). In contrast, the multivariate analysis of patients who had ESCLC revealed that PCI was the sole factor associated with a survival advantage (HR = 0.47 [95% CI 0.24-0.93], p = 0.03). Grade 3 or higher adverse events (AEs) were significantly greater in patients who received PCI (71.4% vs. 47.5%, p = 0.0031), with non-neuro and non-heme being the specific AE categories most strongly correlated with PCI delivery. CONCLUSIONS PCI was associated with a significant improvement in survival for our entire elderly SCLC patient cohort on univariate analysis. Multivariate analysis suggested that the survival advantage remained significant in patients with ESCLC. PCI was also associated with a modest increase in grade 3 or higher AEs.

Scanning proton beam therapy reduces normal tissue exposure in pelvic radiotherapy for anal cancer

An inter-comparison planning study between photon beam therapy (IMRT) and scanning proton beam therapy (SPBT) for squamous cell carcinoma of the anus (SCCA) is presented. SPBT plans offer significant reduction (>50%, P=0.008) in doses to small bowel, and bone marrow thereby offering the potential to reduce bowel and hemotoxicities.

Integration of radiation oncology with surgery as combined-modality treatment.

Integration of surgery and radiation (external beam, EBRT; intraoperative, IORT) has become more routine for patients with locally advanced primary cancers and those with local-regional relapse. This article discusses patient selection and treatment from a more general perspective, followed by a discussion of patient selection and treatment factors in select disease sites (pancreas cancer, colorectal cancer, retroperitoneal soft-tissue sarcomas). Outcomes with combined modality treatment (surgery, EBRT alone or with concurrent chemotherapy, IORT) are discussed. The ultimate in contemporary integration of radiation and surgery is found in patients who are candidates for surgery plus both EBRT and IORT.

Preoperative chemoradiation and IOERT for unresectable or borderline resectable pancreas cancer

BACKGROUND AND OBJECTIVES Pre-operative chemoradiation (preop CRT) plus intraoperative electron irradiation (IOERT) has been used in the multidisciplinary treatment for patients with locally advanced unresectable or borderline resectable pancreas cancer. This review was performed to evaluate survival, relapse patterns and prognostic factors in patients treated with curative intent. METHODS Between January 2002 and December 2010, 48 patients with locally advanced pancreatic ductal adenocarcinoma received preop CRT prior to an attempt at resection and IOERT. 31/48 (65%) patients proceeded to curative-intent surgical resection. Resection status prior to preop CRT was locally unresectable (20 patients) and borderline resectable (11 patients). Preop CRT (45-50.4 Gy/25-28 Fx in 27/31) was delivered with concurrent 5FU or gemcitabine-based regimens. Subsequent gross total resection was achieved in 16 patients (R0, 11; R1, 5). IOERT was delivered in 28 patients (dose, 10-20 Gy). 16 patients also received adjuvant post-operative systemic chemotherapy. Outcomes evaluated include survival, local failure in the EBRT field (LF), central failure in the IOERT field (CF), and distant metastases. RESULTS Resection status was predictive for survival and for patterns of relapse. For patients with at least a gross total resection after preop CRT (R0/R1; n=16) vs. no resection (n=15), both median and overall survival were improved (median 23 vs. 10 months; 2-year, 40% vs. 17%; 3-year, 40% vs. 0%; P=0.002). Liver or peritoneal relapse was documented in 22/31 patients (71%); LF/CF in 5/26 (16%). CONCLUSIONS Long term survival and disease control are achievable in select patients with borderline resectable or locally unresectable pancreas cancer when gross total surgical resection is achieved after preop CRT. Continued evaluation of curative-intent combined modality therapy is warranted in this high risk population, but additional strategies are needed to improve resectability and disease control.

Spot-scanned pancreatic stereotactic body proton therapy: A dosimetric feasibility and robustness study

PURPOSE We explored the dosimetric potential of spot-scanned stereotactic body proton therapy (SBPT) for pancreatic cancer. METHODS We compared SBPT to stereotactic body intensity-modulated radiotherapy (SB-IMRT) in 10 patients. We evaluated 3 variables in SBPT planning: (1) 4 and 6 mm spot size; (2) single vs. multi-field optimization (SFO vs. MFO); and (3) optimization target volume (OTV) expansion. Robustness analysis was performed with unidirectional isocenter shifts of ±3 mm in x, y, and z and ±3% stopping power uncertainties. RESULTS SBPT plans had lower V10Gy for the stomach and small and large bowels. Under static robustness, a 5 mm OTV and SFO-6 mm spot size represented the best compromise between target and normal structure. A 4-mm spot-size and 3 mm OTV resulted in significant target underdosing with deformable dose accumulation analysis. CONCLUSIONS This study provides a critical basis for clinical translation of spot size, optimization technique, and OTV expansion for pancreatic SBPT.