Predictors of lymphopenia in esophageal cancer patients receiving photon or proton radiation therapy: A dosimetric analysis

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Background: Lymphopenia during radiation therapy (RT) has been associated with worse oncologic outcomes in a number of malignancies, including esophageal cancer (EC). No studies to date have investigated specific dosimetric parameters associated with this lymphopenia in EC. We performed an analysis of RT dose to multiple organs at risk (OARs) to investigate associations with grade 4 lymphopenia (G4L). Methods: Consecutive EC patients receiving curative intent chemoradiotherapy +/- surgery between July of 2015 and December of 2017 were included. Lymphocyte nadir was defined as the lowest lymphocyte count during RT. G4L was defined as absolute lymphocyte count <200/mm3. Dose to OARs including aorta, body, bone marrow, heart, liver, lung, and spleen were calculated. Univariate logistic regression analyses were performed for each OAR at the 1, 5, 10, 15, 20, 30, 35, 40, and 50 Gy levels with volume receiving dose ‘x’(VxGy) analyzed as a continuous variable per 10% increase. Clinical tumor volume (CTV) and RT modality (photon vs. proton) as well clinical factors including sex, stage (I/II vs. III/IV), age (per 10 year increase), and BMI (per 5 unit increase) were also analyzed. Results: One hundred forty-four pts were identified for inclusion. Seventy-nine pts received photon RT and 65 proton RT. Chemotherapy was weekly carbotaxol (99%). G4L at nadir was 40% overall (56% photon, 22% proton). By organ, body V1-V30Gy (OR 1.45-8.18, p<0.01), heart V1-V30Gy (OR 1.24-1.49, p<0.01), liver V1-V35Gy (OR 1.23-2.75, p<0.01), lung V1-V30Gy (OR 1.26-5.73 p<0.01), and spleen V1-V40Gy (OR 1.26-1.49 p<0.01) were highly associated with G4L whereas dose to aorta and bone marrow were not. Advanced stage (OR, 3.92 p<0.01), photon vs. proton (OR 4.58 p<0.01), and CTV (per 100 cc’s (OR=1.21, p<0.01)) were also associated with G4L. Sex, age, and BMI were not associated with G4L. Conclusions: Low to intermediate dose volumes to OARs including body, spleen, liver, lungs, and heart were associated with G4L. These findings provide rational for the differences seen in rates of G4L for photon versus proton RT.

Pre-treatment pulmonary function testing as a predictor of cardiopulmonary toxicity in esophageal cancer patients treated with trimodality therapy

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Background: We evaluated the role of pre-treatment pulmonary function testing (PFT) in predicting the likelihood of cardiac and/or pulmonary toxicity for esophagus cancer patients receiving trimodality therapy. Methods: From 2007 to 2013, 64 patients with esophageal cancer received trimodality therapy at a single tertiary center with pre-treatment PFTs. The odds ratio of pre-treatment PFT as a predictor of cardiopulmonary toxicity was assess with univariate analysis (UVA). FEV1 (forced expiratory volume in 1 second) and DLCO (diffusion capacity for carbon monoxide) were assessed per 0.5-unit decrease. Percent FEV1 and DLCO predicted were assessed per 10% decrease. Results: The median age was 62 years (range, 41-79) with 88% male patients. A total of 70% of patients had adenocarcinoma with 66% having stage 3 disease. Most patients were former (43%) or current smokers (32%) and 18% had COPD. One or more cardiac comorbidities were observed in 54% of patients. The median RT dose was 50 Gy and the most frequent concurrent chemotherapy was cisplatin/5FU (53%). The median pre-treatment FEV1 and DLCO was 2.8 liters (range, 1-4.9) and 22.5 mL/min/mmHg (range, 17.2-25.5), respectively. This correlated to a median percent predicted value for FEV1 and DLCO of 85% (range, 30-124%) and 81.5% (range, 49-119%), respectively. The overall rate of any cardiac and pulmonary toxicity was 35% and 50%, respectively. Percent predicted value of both FEV1 and DLCO was statistically associated with pulmonary but not cardiac toxicity (Table). Conclusions: Patients with compromised pre-treatment pulmonary function are at higher risk of developing post-treatment pulmonary toxicities. Pulmonary function testing should be routinely performed prior to initiation of trimodality therapy for patient risk stratification. [Table: see text]

A multicenter study of trimodality therapy for patients 75 years and older with esophageal cancer

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Background: Trimodality therapy is the standard of care for patients with resectable cancer of the esophagus. However, patients ≥75 years have been underrepresented or excluded from landmark clinical trials to date. We investigated the feasibility and safety of treatment of esophageal cancer with trimodality therapy in patients’ ≥ 75 years. Methods: We performed a retrospective review of all patients ≥75 years who received trimodality therapy for esophageal cancer in 3 high volume tertiary cancer institutions from June 2007 to June 2013. All patients received neoadjuvant radiation with concomitant chemotherapy followed by esophagectomy. Toxicities and clinical outcomes were abstracted from the electronic medical record and partially from a prospectively maintained database. Overall and disease-free survival were estimated using the Kaplan-Meier method. Results: Five hundred seventy patients were treated with trimodality therapy for esophageal cancer from 2007-2013. Of these, 38 patients (7%) were 75 or older at the time of diagnosis. At diagnosis, comorbidities included coronary artery disease (32%), atrial fibrillation (11%) and COPD (13%). The majority of patients (87%) received 50.4Gy/28 fractions. 5-fluorouracil (5-FU)/cisplatin was the most common chemotherapy regimen (37%), followed by 5-FU/docetaxel (24%). A total of 13 patients (34%) developed acute grade ≥3 toxicity associated with neoadjuvant therapy. The most common acute grade 3 toxicities were haematological (10%), nausea (8%), esophagitis (5%) and fatigue (5%). Significant postoperative complications included respiratory (empyema, ARDS, pleural effusion) (39%), arrhythmia (32%), anastomotic leak (5%), and ileus (5%). There were 2 deaths (5%) within 90 days of surgery: one was secondary to empyema, the other developed DIC and sepsis. Median overall survival and disease free survival were 4.4 and 2.3 years respectively. Conclusions: Trimodality treatment is a reasonable approach for management of carefully selected elderly patients with esophageal cancer, with similar rates of cancer outcomes, and treatment related morbidity and mortality as compared to younger patients.

A Comparison of Grade 4 Lymphopenia With Proton Versus Photon Radiation Therapy for Esophageal Cancer

Purpose

Grade 4 lymphopenia (G4L) during radiation therapy (RT) is associated with higher rates of distant metastasis and decreased overall survival in a number of malignancies, including esophageal cancer (EC). Through a reduction in integral radiation dose, proton RT (PRT) may reduce G4L relative to photon RT (XRT). The purpose of this study was to compare G4L in patients with EC undergoing PRT versus XRT.

Methods and materials

Patients receiving curative-intent RT and concurrent chemotherapy for EC were identified. Lymphocyte nadir was defined as the lowest lymphocyte count during RT. G4L was defined as absolute lymphocyte count <200/mm³. Univariate and multivariable logistic regression analyses (MVA) were performed to assess patient and treatment factors associated with lymphopenia. A propensity-matched (PM) cohort was created using logistic regression, including baseline covariates.

Results

A total of 144 patients met the inclusion criteria. The median age was 66 years (range, 32-85 years). Of these patients, 79 received XRT (27% 3-dimensional chemo-RT and 73% intensity modulated RT) and 65 received PRT (100% pencil-beam scanning). Chemotherapy consisted of weekly carboplatin and paclitaxel (99%). There were no significant differences in baseline characteristics between the groups, except for age (median 4 years older in the PRT cohort). G4L was significantly higher in patients who received XRT versus those who received PRT (56% vs 22%; P < .01). On MVA, XRT (odds ratio [OR]: 5.13; 95% confidence interval [CI], 2.35-11.18; P < .001) and stage III/IV (OR: 4.54; 95% CI, 1.87-11.00; P < .001) were associated with G4L. PM resulted in 50 PRT and 50 XRT patients. In the PM cohort, G4L occurred in 60% of patients who received XRT versus 24% of patients who received PRT. On MVA, XRT (OR: 5.28; 95% CI, 2.14-12.99; P < .001) and stage III/IV (OR: 3.77; 95% CI, 1.26-11.30; P = .02) were associated with G4L.

Conclusions

XRT was associated with a significantly higher risk of G4L in comparison with PRT. Further work is needed to evaluate a potential association between RT modality and antitumor immunity as well as long-term outcomes.

A Curative-Intent Trimodality Approach for Isolated Abdominal Nodal Metastases in Metastatic Colorectal Cancer: Update of a Single-Institutional Experience

BACKGROUND

The purpose of this study was to define survival rates in patients with isolated advanced abdominal nodal metastases secondary to colorectal cancer (CRC), treated with curative-intent trimodality therapy.

MATERIALS AND METHODS

Sixty-five patients received trimodality therapy, defined as chemotherapy delivered with external beam radiotherapy (EBRT) followed by lymphadenectomy and intraoperative radiotherapy (IORT). Infusional 5-fluorouracil was the most common radiosensitizer used (63%, 41 patients). The median dose of EBRT was 50 Gy, and the median dose of IORT was 12.5 Gy. We evaluated time to distant metastasis, toxicities, local failure within the EBRT field, recurrence within the IORT field, and survival.

RESULTS

Fifty-two percent of patients were male; patients' median age was 50.5 years. All patients had an Eastern Cooperative Oncology Group score ≤1. Twenty-nine patients had right-sided colon cancer, 22 had left-sided colon cancer, and 14 had rectal primaries. The median time from initial CRC diagnosis to development of abdominal nodal metastatic disease was 20.6 months (95% confidence interval [CI], 21.2-40.8 months). Seventy-eight percent (51 patients) had para-aortic nodal metastases, 15% (10 patients) had mesenteric nodal metastases, and 6% (4 patients) had both. With a median follow-up of 77.6 months, the median overall survival and 5-year estimated survival rate were 55.4 months (95% CI, 47.2-80.9 months) and 45%, respectively. The median progression-free survival was 19.3 months (95% CI, 16.5-32.8 months). Twenty-six (40%) patients never developed distant disease. The outcome was not affected by disease sidedness or rectal primary. Treatment was well tolerated without grade 3 or 4 toxicities.

CONCLUSION

Trimodality therapy produces sustainable long-term survival in selected patients with metastatic CRC presenting with isolated retroperitoneal or mesenteric nodal relapse.

IMPLICATIONS FOR PRACTICE

This article reports a unique trimodality approach incorporating external beam radiotherapy with radiosensitizing chemotherapy, surgical resection, and intraoperative radiotherapy provides durable survival benefit with significant curative potential for patients with metastatic colorectal cancer who present with isolated abdominal nodal (mesenteric and/or retroperitoneal) recurrence.

Knowledge of endoscopic ultrasound-delivered fiducial composition and dimension necessary when planning proton beam radiotherapy

BACKGROUND AND STUDY AIMS

Little consideration has been given to selection of endoscopic ultrasound-guided fiducials for proton radiotherapy and the resulting perturbations in the therapy dose and pattern. Our aim was to assess the impact of perturbations caused by six fiducials of different composition and dimensions in a phantom gel model.

MATERIALS AND METHODS

 The phantom was submerged in a water bath and irradiated with a uniform 10 cm × 10 cm field of 119.7 MeV monoenergetic spot scanning protons delivered through a 45 mm range shifter. The proton "Bragg Peak" was evaluated.

RESULTS

 Dose perturbations manifesting as dose reductions up to 30 % were observed. A carbon composite (1 × 5 mm) and gold (0.4 × 10 mm) fiducial with backload potential rather than dedicated EUS pre-loaded gold fiducial needles had the best performance in terms of minimizing the dose perturbation.

CONCLUSIONS

 Our data demonstrate that a carbon composite fiducial has a less untoward effect on proton therapy dose distribution than dedicated EUS pre-loaded gold fiducial needles. Such information is important to consider when selecting fiducials specifically for proton therapy.

Extended-Field Chemoradiation Therapy for Definitive Treatment of Anal Canal Squamous Cell Carcinoma Involving the Para-Aortic Lymph Nodes

PURPOSE

To report cancer control rates and adverse events (AEs) of curative-intent, extended-field chemoradiation therapy administered to patients with squamous cell carcinoma (SCC) of the anal canal presenting with distant metastasis limited to the para-aortic (PA) lymph nodes.

METHODS

This was a retrospective review of patients with SCC of the anal canal metastatic to the PA lymph nodes at initial diagnosis who were treated with curative-intent, extended-field chemoradiation therapy between September 2002 and February 2016 at two tertiary care centers. Outcomes assessed included treatment-related AEs (Common Terminology Criteria for Adverse Events, version 4.0), disease control (cumulative incidence estimates), and survival (Kaplan-Meier estimates).

RESULTS

Thirty patients were included. Involved and elective PA nodes were treated to median doses of 51 Gy (range 45-57.6) and 45 Gy (range 30.6-50.4) in 29 fractions (range 17-32). All patients received one of these concomitant regimens: 6 weekly cycles of cisplatin with 5-fluoruracil/capecitabine (5-FU) (n = 22), 2 cycles of mitomycin-C with 5-FU (n = 7), or daily capecitabine (n = 1). After a median follow-up period of 3.1 years, 18 patients (60%) remained alive and 17 patients were without evidence of anal cancer after definite and salvage treatments. Overall and disease-free survival at 3 years was 67% (95% CI 49%-89%) and 42% (95% CI 25%-69%). Fifteen (50%) patients experienced a recurrence at a median of 0.9 year (range 0.5-3.5 years). The predominant site of recurrence was distant metastases, with a 3-year cumulative incidence of 50% (95% CI 20%-68%). There was no acute grade 5 AE. Grade 3 to 4 gastrointestinal, dermatologic, and hematologic AEs occurred in 30%, 27%, and 20% of patients respectively.

CONCLUSIONS

Extended-field chemoradiation therapy is a potentially curative treatment option for patients presenting with SCC of the anal canal with metastases limited to the PA lymph nodes.

Initial experience with intensity modulated proton therapy for intact, clinically localized pancreas cancer: Clinical implementation, dosimetric analysis, acute treatment-related adverse events, and patient-reported outcomes

Purpose

Pencil-beam scanning intensity modulated proton therapy (IMPT) may allow for an improvement in the therapeutic ratio compared with conventional techniques of radiation therapy delivery for pancreatic cancer. The purpose of this study was to describe the clinical implementation of IMPT for intact and clinically localized pancreatic cancer, perform a matched dosimetric comparison with volumetric modulated arc therapy (VMAT), and report acute adverse event (AE) rates and patient-reported outcomes (PROs) of health-related quality of life.

Methods and materials

Between July 2016 and March 2017, 13 patients with localized pancreatic cancer underwent concurrent capecitabine or 5-fluorouracil-based chemoradiation therapy (CRT) utilizing IMPT to a dose of 50 Gy (radiobiological effectiveness: 1.1). A VMAT plan was generated for each patient to use for dosimetric comparison. Patients were assessed prospectively for AEs and completed PRO questionnaires utilizing the Functional Assessment of Cancer Therapy-Hepatobiliary at baseline and upon completion of CRT.

Results

There was no difference in mean target coverage between IMPT and VMAT (P > .05). IMPT offered significant reductions in dose to organs at risk, including the small bowel, duodenum, stomach, large bowel, liver, and kidneys (P < .05). All patients completed treatment without radiation therapy breaks. The median weight loss during treatment was 1.6 kg (range, 0.1-5.7 kg). No patients experienced grade ≥3 treatment-related AEs. The median Functional Assessment of Cancer Therapy-Hepatobiliary scores prior to versus at the end of CRT were 142 (range, 113-163) versus 136 (range, 107-173; P = .18).

Conclusions

Pencil-beam scanning IMPT was feasible and offered significant reductions in radiation exposure to multiple gastrointestinal organs at risk. IMPT was associated with no grade ≥3 gastrointestinal AEs and no change in baseline PROs, but the conclusions are limited due to the patient sample size. Further clinical studies are warranted to evaluate whether these dosimetric advantages translate into clinically meaningful benefits.

Data collection of patient outcomes: one institution's experience

Patient- and provider-reported outcomes are recognized as important in evaluating quality of care, guiding health care policy, comparative effectiveness research, and decision-making in radiation oncology. Combining patient and provider outcome data with a detailed description of disease and therapy is the basis for these analyses. We report on the combination of technical solutions and clinical process changes at our institution that were used in the collection and dissemination of this data. This initiative has resulted in the collection of treatment data for 23 541 patients, 20 465 patients with provider-based adverse event records, and patient-reported outcome surveys submitted by 5622 patients. All of the data is made accessible using a self-service web-based tool.

Postresection CA19-9 and margin status as predictors of recurrence after adjuvant treatment for pancreatic carcinoma: Analysis of NRG oncology RTOG trial 9704

Purpose

NRG Oncology RTOG 9704 was the first adjuvant trial to validate the prognostic value of postresection CA19-9 levels for survival in patients with pancreatic carcinoma. The data resulting from this study also provide information about predictors of recurrence that may be used to tailor individualized management in this disease setting. This secondary analysis assessed the prognostic value of postresection CA19-9 and surgical margin status (SMS) in predicting patterns of disease recurrence.

Methods and materials

This multicenter cooperative trial included participants who were enrolled as patients at oncology treatment sites in the United States and Canada. The study included 451 patients analyzable for SMS, of whom 385 were eligible for postresection CA19-9 analysis. Postresection CA19-9 was analyzed at cut points of 90, 180, and continuously. Patterns of disease recurrence included local/regional recurrence (LRR) and distant failure (DF). Multivariable analyses included treatment, tumor size, and nodal status. To adjust for multiple comparisons, a P value of ≤ .01 was considered statistically significant and > .01 to ≤ .05 to be a trend.

Results

For CA19-9, 132 (34%) patients were Lewis antigen-negative (no CA19-9 expression), 200 (52%) had levels <90, and 220 (57%) had levels <180. A total of 188 patients (42%) had negative margins, 152 (34%) positive, and 111 (25%) unknown. On univariate analysis, CA19-9 cut at 90 was associated with increases in LRR (trend) and DF. Results were similar at the 180 cut point. SMS was not associated with an increase in LRR on univariate or multivariate analyses. On multivariable analysis, CA19-9 ≥ 90 was associated with increased LRR and DF. Results were similar at the 180 cut point.

Conclusions

In this prospective evaluation, postresection CA19-9 was a significant predictor of both LRR and DF, whereas SMS was not. These findings support consideration of adjuvant radiation therapy dose intensification in patients with elevated postresection CA19-9.

Pelvis Ewing sarcoma: Local control and survival in the modern era

PURPOSE

Local control for Ewing sarcoma (ES) has improved in modern studies. However, it is unclear if these gains have also been achieved for pelvis tumors. The purpose of this study is to evaluate local control and survival in pelvis ES patients treated in the modern era.

METHODS

All pelvis ES patients diagnosed from 1990 to 2012 and seen at Mayo Clinic were identified. Factors relevant to survival and local control were analyzed.

RESULTS

The cohort consisted of 48 patients. Fifty-two percent had metastatic disease at diagnosis. The 5-year overall survival and event-free survival was 73% and 65%, respectively, for localized disease. The 5-year cumulative incidence of local recurrence was 19%, with a 26% incidence for radiation, 13% for surgery, and 0% for surgery + radiation (P = 0.54). All local failures occurred in-field. Sacral involvement by tumor trended toward a higher incidence of local recurrence (hazard ratio 3.06, P = 0.09). Patients treated with definitive radiation doses ≥5,600 cGy had a lower incidence of local recurrence (17% vs. 28%, P = 0.61).

CONCLUSIONS

Our study demonstrates excellent survival for localized tumors in the modern era. Anatomical localization within the pelvis likely correlates with outcomes. Local control remains problematic, especially for patients treated with definitive radiation. Though statistically not significant, surgery + radiation and definitive radiation dose ≥5,600 cGy were associated with the lowest incidence of local failure, suggesting treatment intensification may improve local control for pelvis ES.

The role of neoadjuvant radiotherapy for locally-advanced rectal cancer with resectable synchronous metastasis

BACKGROUND

Although neoadjuvant radiotherapy is typically administered for locally-advanced rectal cancer to reduce local recurrence (LR), its role for patients who present with synchronous resectable liver and/or lung metastasis is not well defined. The aim of this study was to evaluate the role of neoadjuvant radiotherapy for patients with stage IV rectal cancer undergoing curative-intent surgery.

METHODS

This study is a retrospective review of a prospectively maintained surgical registry of all consecutive adult patients who underwent curative-intent resection at Mayo Clinic in Rochester, MN, from January 1990 until December 2014 with a median follow-up time of 43 (IQR 16-67) months. Eligible patients had locally-advanced rectal cancer (T3, T4 and/or nodal involvement) with synchronous resectable liver and/or lung metastasis. Exclusion criteria were as follows: patients with primary tumor stage of T1N0 or T2N0, patients with metastasis to organs other than the liver or lung, patients who had palliative resection, patients who had non-surgical treatment of synchronous metastasis (e.g., radiofrequency ablation), patients who received postoperative radiotherapy, or absence of research authorization. Ninety three patients were included of which 47 received neoadjuvant radiotherapy and 46 did not. All patients received neoadjuvant chemotherapy +/- radiotherapy followed by curative-intent surgery with metastasectomy performed either simultaneously with resection of the primary tumor or as a planned staged resection. The primary outcomes of this study are LR, distant metastasis, overall and disease-specific survival (DSS).

RESULTS

LR was observed in 12 patients (26%) who did not receive radiotherapy, while no LR developed in those who received neoadjuvant radiotherapy, P<0.001. Univariate analysis showed that neither age, sex, ASA class, BMI, tumor location, procedure performed, or neoadjuvant chemotherapy were associated with subsequent LR. The 5-year overall survival (OS) rates were: 43.3% (95% CI: 30.1, 62.3) for no radiotherapy vs. 58.3% (95% CI: 43.4, 78.2) with radiotherapy.

CONCLUSIONS

Neoadjuvant radiotherapy should be considered in patients with locally-advanced stage IV rectal cancer. These data add to the evidence supporting neoadjuvant radiotherapy in the setting of resectable metastatic disease.

EUS-guided fine-needle injection of gemcitabine for locally advanced and metastatic pancreatic cancer

BACKGROUND AND AIMS

Among the greatest hurdles to pancreatic cancer (PC) therapy is the limited tissue penetration of systemic chemotherapy because of tumor desmoplasia. The primary study aim was to determine the toxicity profile of EUS-guided fine-needle injection (EUS-FNI) with gemcitabine. Secondary endpoints included the ability to disease downstage leading to an R0 resection and overall survival (OS) at 6 months, 12 months, and 5 years after therapy.

METHODS

In a prospective study from a tertiary referral center, gemcitabine (38 mg/mL) EUS-FNI was performed in patients with PC before conventional therapy. Initial and delayed adverse events (AEs) were assessed within 72 hours and 4 to 14 days after EUS-FNI, respectively. Patients were followed for ≥5 years or until death.

RESULTS

Thirty-six patients with stage II (n = 3), stage III (n = 20), or stage IV (n = 13) disease underwent gemcitabine EUS-FNI with 2.5 mL (.7-7.0 mg) total volume of injectate per patient. There were no initial or delayed AEs reported. Thirty-five patients (97.2%) were deceased at the time of analysis with a median 10.3 months of follow-up (range, 3.1-63.9). OS at 6 months and 12 months was 78% and 44%, respectively. The median OS was 10.4 months (range, 2.7-68). Among patients with stage III unresectable disease, 4 (20%) were downstaged and underwent an R0 resection.

CONCLUSIONS

Our study suggests the feasibility, safety, and potential efficacy of gemcitabine EUS-FNI for PC. Additional data are needed to verify these observations and to determine the potential role relative to conventional multimodality therapy.

Results of the randomized phase II portion of NRG Oncology/RTOG 0848 evaluating the addition of erlotinib to adjuvant gemcitabine for patients with resected pancreatic head adenocarcinoma

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Background: NRG/RTOG 0848 is a 2-step study designed to determine whether erlotinib (E) added to gemcitabine (G) (randomized Ph II) &/or adjuvant radiation with concurrent 5-FU or capecitabine following 6 months of systemic chemotherapy (Ph III), improve survival in patients (pts) with resected pancreatic head adenocarcinoma. The erlotinib results are reported here. Methods: Eligible pts include those with resected pancreatic head adenocarcinoma, pathologic stage T1-T3, N0-1, M0; PS 0-1, & CA19-9 ≤ 180 IU/L. Pts in Arms 1 & 2 received G 1 gm/m2 weekly for 3 weeks in a 28-day cycle for 6 cycles. Pts in Arm 2 also received E 100 mg/day. The primary hypothesis for the E portion was that G+E would increase overall survival (OS) compared to G alone. With a 1-sided alpha of 0.15, 200 OS events provide 80%/90% power to detect a signal for an increase in median OS from 22 to 28.8/30.6 months (mos). OS was estimated by the Kaplan-Meier method & arms compared using the log rank test. The Cox proportional hazards model was used to analyze treatment effect. Results: 336 pts were randomized from 11/17/2009 to 2/28/2014, with 163 pts evaluable for G and 159 for G+E. Median age was 63 years (39-86). Most pts had pathologic T3 disease (78%) & CA19-9 ≤ 90 (93%). There are 32 pts (20%) with grade 4 adverse events (AEs) & 2 pts (1%) with grade 5 AEs on G and 27 (17%) & 3 (2%) on G+E arm, respectively. There are fewer grade ≥ 3 GI AEs on the G arm (22%) as compared to the G+E arm (28%), and 110 (69.2%) & 93 (59.6%) pts received at least 85% of planned G dose for the G & G+E arms, respectively. 58% of E pts received at least 85% of planned E dose. The median follow-up for alive pts is 42.5 mos (min-max: < 1-75). With 203 deaths, median & 3-yr OS (95% CI) are 29.9 mos (21.7-33.4) & 39% (30, 45) for G and 28.1 mos (20.7-30.9) & 39% (31, 47) for G+E; log-rank p = 0.62. The hazard ratio (95% CI) comparing OS of G+E to G is 1.04 (0.79- 1.38). Conclusions: The addition of adjuvant E to G did not provide a signal for increased OS in pts with resected pancreatic head cancer compared to G alone. Accrual to the trial is continuing to answer the Ph III radiation question. Clinical trial information: NCT01013649.

A curative intent trimodality approach for advanced isolated abdominal nodal metastasis in metastatic colorectal cancer: Update of a single-institutional experience

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Background: To define and update survival rates and relapse patterns in patients (pts) with isolated advanced abdominal nodal metastasis secondary to colorectal cancer (CRC), treated with curative intent using aggressive trimodality therapy. Methods: Fifty-seven pts with isolated advanced abdominal lymph node metastasis (retroperitoneal and mesenteric) secondary to colorectal cancer received trimodality therapy defined as chemotherapy delivered in conjunction with external beam radiotherapy (EBRT) followed by lymphadenectomy and intraoperative radiotherapy (IORT). Infusional 5-FU was the most common radiosensitizer used (66%, 38 pts). The median dose of EBRT was 50 Gy & the median dose of intraoperative radiotherapy was 12.5 Gy. End points included distant metastasis, toxicities, local failure within EBRT field, recurrence within the intraoperative radiotherapy field, and survival. Results: 49% of pts were male, median age 50.5 yrs. All patients had ECOG ≤ 1. 27 pts had primary right sided colon cancer, 16 left sided colon cancer and 14 rectal primaries. Median time from initial CRC diagnosis to development of abdominal lymph node metastatic disease was 24 months (95% CI, 23.5-45.1 months). 84% (48 pts) had paraaortic nodal metastases, 12% (7 pts) had mesenteric nodal metastases, and 3% (2 pts) had both. With a median follow up of 89.4 months, the median overall survival and 5-year estimated survival rate were 53.2 months (95% CI, 46.4-78.8 months) and 42%, respectively. Median progression free survival was 19.3 months (95% CI, 15.6-32.8 months). 21 (37%) pts never developed distant disease. Outcome was not affected by disease sidedness, rectal primary, or mutational profile. Treatment was well tolerated without any grade 3/4 toxicities. Conclusions: The use of trimodality therapy including EBRT with radiosensitizing chemotherapy, lymphadenectomy and IORT produces sustainable long-term survival in selected metastatic CRC pts presenting with isolated retroperitoneal/mesenteric nodal relapse.

Intraoperative radiation therapy for colon and rectal cancers: a clinical review

Although there have been significant advances in the adjuvant therapy of colorectal cancer, results for patients have historically been poor when complete resection is unlikely or not possible. Similarly, locally recurrent colorectal cancer patients often experience significant tumor related morbidity and disease control and long term survival have historically been poor with standard therapies. Intraoperative radiation therapy (IORT) has been proposed as a possible tool for dose escalation in patients with locally advanced colorectal cancer.

For patients with locally advanced primary or recurrent colon cancer, the absence of prospective controlled trials limits the ability to draw definitive conclusions in completely resected patients. In subtotally resected patients, the available evidence is consistent with marked improvements in disease control and survival compared to historical controls. For patients with locally advanced primary or recurrent rectal cancer, a relatively large body of evidence suggests improved disease control and survival, especially in subtotally resected patients, with the addition of IORT to moderate dose external beam radiation (EBRT) and chemotherapy. The most important prognostic factor in nearly all series is the completeness of surgical resection. Many previously irradiated patients may be carefully re-treated with radiation and IORT in addition to chemotherapy resulting in long term survival in more than 25% of patients. Peripheral nerve is dose limiting for IORT and patients receiving 15 Gy or more are at higher risk.

IORT is a useful tool when dose escalation beyond EBRT tolerance limits is required for acceptable local control in patients with locally advanced primary or recurrent colorectal cancer. Previously irradiated patients should not be excluded from treatment consideration.

Results of intraoperative electron beam radiotherapy containing multimodality treatment for locally unresectable T4 rectal cancer: a pooled analysis of the Mayo Clinic Rochester and Catharina Hospital Eindhoven

BACKGROUND

The aim of this study is to analyse the pooled results of intraoperative electron beam radiotherapy (IOERT) containing multimodality treatment of locally advanced T4 rectal cancer, initially unresectable for cure, from the Mayo Clinic, Rochester, USA (MCR) and Catharina Hospital, Eindhoven, The Netherlands (CHE), both major referral centers for locally advanced rectal cancer. A rectal tumor is called locally unresectable for cure if after full clinical work-up infiltration into the surrounding structures or organs has been demonstrated, which would result in positive surgical margins if resection was the initial component of treatment. This was the reason to refer these patients to the IOERT program of one of the centers.

METHODS

In the period from 1981 to 2010, 417 patients with locally unresectable T4 rectal carcinomas at initial presentation were treated with multimodality treatment including IOERT at either one of the two centres. The preferred treatment approach was preoperative (chemo) radiation and intended radical surgery combined with IOERT. Risk factors for local recurrence (LR), cancer specific survival, disease free survival and distant metastases (DM) were assessed.

RESULTS

A total of 306 patients (73%) underwent a R0 resection. LRs and metastases occurred more frequently after an R1-2 resection (P<0.001 and P<0.001 respectively). Preoperative chemoradiation (preop CRT) was associated with a higher probability of having a R0 resection. Waiting time after preoperative treatment was inversely related with the chance of developing a LR, especially after R+ resection. In 16% of all cases a LR developed. Five-year disease free survival and overall survival (OS) were 55% and 56% respectively.

CONCLUSIONS

An acceptable survival can be achieved in treatment of patients with initially unresectable T4 rectal cancer with combined modality therapy that includes preop CRT and IOERT. Completeness of the resection is the most important predictive and prognostic factor in the treatment of T4 rectal cancer for all outcome parameters. IOERT can reduce the LR rate effectively, especially in R+ resected patients.

Results of a pooled analysis of IOERT containing multimodality treatment for locally recurrent rectal cancer: Results of 565 patients of two major treatment centres

OBJECTIVE

Aim of this study is analysing the pooled results of Intra-Operative Electron beam Radiotherapy (IOERT) containing multimodality treatment of locally recurrent rectal cancer (LRRC) of two major treatment centres.

METHODS AND MATERIALS

Five hundred sixty five patients with LRRC who underwent multimodality-treatment up to 2010 were studied. The preferred treatment was preoperative chemo-radiotherapy, surgery and IOERT. In uni- and multivariate analyses risk factors for local re-recurrence, distant metastasis free survival, relapse free survival, cancer-specific survival and overall survival were studied.

RESULTS

Two hundred fifty one patients (44%) underwent a radical (R0) resection. In patients who had no preoperative treatment the R0 resection rate was 26%, and this was 43% and 50% for patients who respectively received preoperative re-(chemo)-irradiation or full-course radiotherapy (p < 0.0001). After uni- and multivariate analysis it was found that all oncologic parameters were influenced by preoperative treatment and radicality of the resection. Patients who were re-irradiated had a similar outcome compared to patients, who were radiotherapy naive and could undergo full-course treatment, except the chance of local re-recurrence was higher for re-irradiated patients. Waiting-time between preoperative radiotherapy and IOERT was inversely correlated with the chance of local re-recurrence, and positively correlated with the chance of a R0 resection.

CONCLUSIONS

R0 resection is the most important factor influencing oncologic parameters in treatment of LRRC. Preoperative (chemo)-radiotherapy increases the chance of achieving radical resections and improves oncologic outcomes. Short waiting-times between preoperative treatment and IOERT improves the effectiveness of IOERT to reduce the chance of a local re-recurrence.

Utility of 18F-FDG PET for Predicting Histopathologic Response in Esophageal Carcinoma following Chemoradiation

INTRODUCTION

For patients with esophageal cancer undergoing neoadjuvant chemoradiation (CRT) followed by surgical resection, complete histopathologic response (pCR) is associated with favorable overall survival (OS). The aim of this study was to evaluate the correlation between ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG PET) response to neoadjuvant CRT and pCR.

METHODS

Maximum standardized uptake values and standardized uptake ratios (SURs) were measured before and after CRT. SUR was normalized to liver uptake and mediastinal blood pool uptake. FDG PET complete response was defined as metabolic activity normalization to hepatic and blood pool activity. The correlation between FDG PET parameters and pCR was examined through logistic regression analyses.

RESULTS

In total, 193 patients were monitored for a median of 3.6 years after initiation of CRT. Most tumors were adenocarcinoma (85%) and stage T3 (75%). Complete FDG PET response and pCR occurred in 27% and 34% of patients, respectively. Histologic findings, chemotherapy type, tumor stage, and radiation dose were not significantly associated with complete radiographic response. The rates of pCR in patients with and without radiographic complete response were 42% and 31% (p = 0.17), respectively. No predictive correlation was found between pCR and change in maximum standardized uptake value (p = 0.25), in SUR normalized to blood pool uptake (p = 0.20), or in SUR normalized to liver uptake (p = 0.15). The 5-year OS rate was 46% for patients with a complete FDG PET response versus 44% without a complete response (p = 0.78). The 5-year OS rate of patients who achieved pCR was 49% versus 43% for patients with residual tumor (p = 0.04).

CONCLUSION

For patients with esophageal cancer who received neoadjuvant chemoradiation, pretreatment and posttreatment FDG PET parameters did not correlate with pCR or OS.

Irradiation of Very Locally Advanced and Recurrent Rectal Cancer

Adjuvant therapy with chemoradiation or short-course radiation in addition to improvements in surgical technique has led to improved outcomes for patients with locally advanced rectal cancer. Local recurrence rates of less than 10% and 5-year survival rate of 60% or higher is expected. However, for patients with very locally advanced primary or locally recurrent disease in whom surgical resection is likely to be associated with incomplete resection, survival and disease control rates are poor and standard doses of adjuvant radiation or chemoradiation are relatively ineffective. Dose-escalation approaches with intraoperative radiation (IORT) have been explored in both the primary and recurrent setting. Although high-level evidence is lacking, available data suggest improvements in local and distant control leading to improved survival with IORT approaches. This review summarizes the evidence for dose-escalation approaches with IORT for patients with very locally advanced and recurrent rectal cancer.

Adjuvant pelvic radiotherapy in patients with stage IVA rectal adenocarcinoma

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Background: For patients with stage IVA rectal cancer with liver metastases treated with curative-intent chemotherapy and surgery, the role of adjuvant pelvic radiotherapy (RT) is unclear. The purpose of this study was to evaluate the impact of pelvic RT on oncologic outcomes in this patient population. Methods: We retrospectively reviewed medical records of all patients with stage IVA rectal adenocarcinoma with liver metastases treated with curative-intent resection of the primary tumor and all liver metastases at our institution between 1991 and 2010. Patient and treatment characteristics were compared between patients who did or did not receive pelvic RT using chi-square and unpaired ttests. Survival and recurrence estimates were calculated from date of initial diagnosis using the Kaplan-Meier method. Local recurrence (LR) was defined as recurrence in the pelvis occurring at or before distant recurrence (DR). Cox regression was used to compare rates of freedom from LR (FFLR), freedom from DR (FFDR), and overall survival (OS) between patients who did or did not receive pelvic RT. Results: The analysis included 65 patients. Median patient age at diagnosis was 59 years (range, 27-87). Tumor stage was T2 (n = 4), T3 (n = 53), or T4 (n = 8). The median number of liver metastases was 2 (range, 1-14). Surgery was low anterior resection (n = 54) or abdominoperineal resection (n = 11). All patients received perioperative fluoropyrimidine based chemotherapy. Pelvic RT was administered to 35 patients (54%), either preoperatively (n = 22) or postoperatively (n = 13). Median RT dose was 50.4 Gy (range 25-58). Patient characteristics were similar for those who did or did not receive pelvic RT. Median follow-up was 3.7 years. The 3-year estimates of FFLR, FFDR and OS were 81% vs 58% (p =.056), 35% vs 29% (p =.75), and 66% vs 71% (p =.81) for RT vs no RT, respectively. Conclusions: In this analysis of patients with stage IVA rectal cancer with liver metastases undergoing curative intent therapy, pelvic RT (vs. no pelvic RT) was associated with a trend to lower rates of LR and similar rates of DR and OS.

Establishment of practice standards in nomenclature and prescription to enable construction of software and databases for knowledge-based practice review

INTRODUCTION

Establishment of standards within a practice and across disease site groups for nomenclatures, prescription formatting, and measured dose-volume histogram (DVH) metrics is a key enabling step for creating software and database solutions to make routine aggregation of dosimetric data for all patients treated in a practice, practical. A process of physician-driven, iterative dialogs coupled with development of technical tools is required to implement the cultural and procedural changes. The cumulative reward for this effort is a database that can be used for defining practice norms, benchmarking against national standards, and tracking dosimetric effects of longitudinal practice pattern changes.

METHODS AND MATERIALS

A 4-year project was carried out to develop and introduce standardizations, modify processes, and develop computer-based tools for reporting, aggregation, and analysis of prescription and DVH metrics. Physician disease site groups developed 42 target and 81 normal tissue templates. From the database of 32,002 DVH metrics, benchmarking was illustrated for a subgroup of breast (281) and prostate (324) patients treated with conventional fractionation over a 16-month period. Breast patients were segregated according to prescription template used: simple (S, tangents only) vs complex (C, tangents + supraclavicular ± intramammary nodes) and left (S-L or C-L) versus right (S-R or C-R).

RESULTS

Prostate patients' median and 50% confidence intervals (CIs) for bladder, stated according to the nomenclature: the percentage of bladder volume receiving doses of ≥40 Gy (V40[%]), V65Gy[%], V70Gy[%], V75Gy[%], and V80Gy[%] were 45.5 (24.9-57.0), 15.6 (9.0-23.8), 7.6 (3.3-13.6), 2.0 (0.0-7.9), and 0.0 (0.0-1.4), respectively. Values for rectum: V50Gy[%], V60 Gy[%], V65Gy[%], V70Gy[%], and V75Gy[%] were 37.1 (27.8-43.5), 21.8 (15.6-25.5), 14.6 (9.6-18.0), 7.7 (1.9-12.3), and 1.0 (0-7.0), respectively. For breast patients, heart:mean Gray values were 1.5 (1.0-2.0), 3.1 (2.2-4.8), 0.4 (0.3-0.7), and 1.1 (0.8-2.2) for S-L, C-L, S-R, and C-R, respectively. Longitudinal, moving window plots of median, 50% CI, and 90% CI for 6-month periods demonstrated the effect of practice changes to reduce heart doses.

CONCLUSIONS

Standardization was challenging as a practice change, but has resulted in significant improvements for both our clinical and research efforts.

Stereotactic body radiotherapy for primary and metastatic liver tumors - the Mayo Clinic experience

INTRODUCTION

To better understand the efficacy of liver SBRT we reviewed our prospectively collected institutional SBRT database.

METHODS

Between May 2008 and March 2013, 80 patients with 104 liver lesions received SBRT. The Kaplan-Meier method estimated local control (LC), overall survival (OS). Cox proportional hazards regression models identified factors associated with LC and OS.

RESULTS

The median follow-up for living patients was 38.6 months. Patients had primary (n=17) or metastatic (n=63) tumors. The median tumor size was 2.7 cm (range, 0.6-14.0). The 1 and 4 year rates of LC were 89.4% and 88%, respectively. Colorectal (CRC) metastasis was associated with lower rates of LC (p=0.013). OS at 1 and 4 years was 78% and 25%, respectively. Patients with CRC metastases had higher rates of OS (p=0.03). The occurrence of severe acute and late toxicity was 3.8% and 6.3%, respectively.

CONCLUSIONS

SBRT should be studied in prospective clinical trials compared with other liver-directed treatment modalities.

Endoscopically inserted nasobiliary catheters for high dose-rate brachytherapy as part of neoadjuvant therapy for perihilar cholangiocarcinoma

BACKGROUND AND AIM

Selected patients with unresectable perihilar cholangiocarcinoma can undergo neoadjuvant chemoradiotherapy followed by liver transplantation, which has been shown to improve survival. The aim of this study was to determine the feasibility and safety of endoscopic transpapillary insertion of nasobiliary tubes (NBTs) and brachytherapy catheters for high dose-rate (HDR) brachytherapy as part of this neoadjuvant chemoradiotherapy.

PATIENTS AND METHODS

Medical records of patients undergoing biliary brachytherapy for hilar cholangiocarcinoma at the Mayo Clinic, Rochester were reviewed. Patients were treated with curative intent using external beam radiotherapy (4500 cGy), chemotherapy (5-FU or capecitabine), and HDR brachytherapy (930 - 1600 cGy in one to four fractions delivered over 1 - 2 days) prior to planned liver transplantation.

RESULTS

Between 2009 and 2013, 40 patients underwent biliary HDR brachytherapy via endoscopically placed NBTs (8.5 - 10 Fr). Patients had a median age of 55 years (range 28 - 68); 25 patients (62.5 %) had primary sclerosing cholangitis. Prior to therapy, 29 patients (72.5 %) had plastic stents, two (5 %) had metal stents, and nine (22.5 %) had no stents. Bilateral NBTs were placed in five patients (12.5 %). NBT/brachytherapy catheter displacement was seen in eight patients (20 %) - five intraprocedure and three post-procedure. A radiotherapy error and NBT kinking each occurred once. Post-procedure adverse events included: cholangitis (n = 5; 12.5 %), severe abdominal pain (n = 3; 7.5 %), duodenopathy (n = 3; 7.5 %), gastropathy (n = 3; 7.5 %), and both duodenopathy and gastropathy (n = 2; 5 %).

CONCLUSION

HDR biliary brachytherapy administered via endoscopically placed NBTs and brachytherapy catheters is technically feasible and appears reasonably safe in selected patients with unresectable perihilar cholangiocarcinoma.

Vaginal brachytherapy for early-stage carcinosarcoma of the uterus

OBJECTIVE

Uterine carcinosarcoma (CS) is an aggressive malignancy and the optimal adjuvant treatment is not well-established. We report outcomes with vaginal brachytherapy (VB) for women with early-stage CS.

METHODS AND MATERIALS

A multi-institutional retrospective study of Stage I-II CS treated with hysterectomy, surgical staging, and adjuvant high-dose-rate VB without external-beam pelvic radiotherapy was performed. Rates of vaginal control, pelvic control, locoregional control, disease-free survival, and overall survival were determined using the Kaplan-Meier method.

RESULTS

33 patients were identified. Prescribed VB dose was 21 Gy in three fractions (n = 15 [45%]) or 24 Gy in six fractions (n = 18 [55%]). Eighteen patients (55%) received chemotherapy. Median followup was 2.0 years. Twenty-seven patients (82%) underwent pelvic lymphadenectomy, 5 (15%) had nodal sampling, and 1 (3%) had no lymph node assessment. Relapse occurred in 11 patients (33%), all of whom had lymph node evaluation. Locoregional relapse was a component of failure in 6 patients (18%), of whom 3 (9%) failed in the pelvis alone. Three patients (9%) had simultaneous distant and locoregional relapse (two vaginal, one pelvic). Five additional patients (15%) had distant relapse. Six of the 11 patients (55%) with disease recurrence received chemotherapy. Two-year vaginal control and pelvic control were 94% and 87%. Two-year locoregional control, disease-free survival, and overall survival were 81%, 66%, and 79%.

CONCLUSIONS

Despite having early-stage disease and treatment with VB, patients in this series had relatively high rates of local and distant relapse. Patients who undergo lymphadenectomy and VB remain at risk for relapse. Novel treatment strategies are needed.

CA19-9 and surgical margin status (SMS) associations with local-regional (LRF) and distant failure (DF) in patients (Pts) with pancreatic cancer: RTOG 9704 secondary analysis

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Background: 9,704 was the first phase 3 pancreatic cancer trial to validate the prognostic value of postresection CA19-9 for overall survival (OS), with values > 90/180 associated with worse OS. All pts received adjuvant gemcitabine or 5-FU and chemo-radiotherapy (RT). This analysis evaluates patterns of disease failure. Methods: SMS was negative, positive, or unknown. CA19-9 was analyzed at cut points 90, 180 and continuously. LRF and DF were estimated by cumulative incidence and Gray’s test compared. Cox hazard models were used for multivariate analyses (MVA) and included treatment, tumor site, size and nodal status. To adjust for multiple comparisons a p-value < 0.01 is statistically significant and 0.01 to < 0.05 a trend. Results: 538 pts accrued, with 451 eligible and analyzable for SMS and 385 for CA19-9. For CA19-9, 132 (34%) were Lewis Antigen negative (no CA19-9 expression), 200 (52%) < 90 and 220 (57%) < 180. 188 (42%) had negative margins, 152 (34%) positive and 111 (25%) unknown (i.e., no margin comment in path report; shown to have outcomes similar to negative margin pts). Pts with CA19-9 ≥ 180 were more likely to have tumors ≥ 3 cm and pts with positive SMS more likely to have KPS 60 - 80, T3/T4, or N1 disease. On univariate analysis (UVA) CA19-9 cut at 90 was associated with significant increases in both LRF (trend) and DF; in the gemcitabine arm this was seen in DF, not in LRF; in the 5-FU arm it was seen in both. Results were similar at the 180 cut point and continuously. SMS on UVA was not associated with increase in LRF/DF; see Table. On MVA, CA19-9 > 90 was significantly associated with LRF and DF; positive SMS showed only a trend for DF. Conclusions: Postresection CA19-9 has significant association with both LRF and DF not seen with SMS. These findings support continued use of RT in trials and consideration of dose intensification among pts with elevated postresection CA19-9. Grants: NCI U10, CA21661, CA37422, CA180868, CA180822. Clinical trial information: 0000000. [Table: see text]

Impact of radiotherapy duration on outcomes in patients with esophageal cancer treated with definitive concurrent radiotherapy and chemotherapy on RTOG trials 8501 and 9405

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Background: Radiotherapy (RT) interruptions have a negative impact on outcomes in many epithelial malignancies treated with definitive RT. The purpose of this study was to analyze the impact of RT duration on outcomes in patients (pts) with esophageal cancer treated with definitive chemoradiotherapy (CRT). Methods: Pts treated with definitive CRT on RTOG trials 8501 and 9405 were included. Separate analyses were performed in pts receiving standard dose (SD-CRT; 50 Gy + 5FU + cisplatin) and high dose (HD-CRT; 64.8 Gy + 5FU + cisplatin) CRT. Local (LF) and regional (RF) failure were estimated by the cumulative incidence method. Disease-free (DFS) and overall (OS) survival were estimated by the Kaplan-Meier method. Univariate (UVA) and multivariate (MVA) Cox proportional hazards models were utilized to examine for correlation between RT duration (< vs. ≥ median) with LF, RF, DFS and OS. Results: In the SD-CRT cohort (n=235), 96 pts (41%) had ≥ 1 RT interruption for a median of 3 (IQR 1-6) days. The median RT duration was 39 (IQR 37-43) days. In UVA and MVA, RT duration was not associated with LF, RF, DFS, or OS. Estimated outcome rates are in the table. In the HD-CRT cohort (n=107), 64 pts (60%) had ≥ 1 RT interruption for a median of 3.5 (IQR 2-7.5) days. The median RT duration was 52 (IQR 50-57) days. In UVA, RT duration ≥ 52 days was associated with a 33% reduction in risk of DFS failure (HR=0.66, 95% CI [0.44-0.98], p=0.039) and a 29% reduction in risk of death (HR=0.71, 95% CI [0.48-1.06], p=0.09). When excluding the 25 pts with RT dose < 64.8 Gy, RT duration was not associated with DFS or OS. Conclusions: In pts with esophageal cancer receiving definitive SD-CRT, an association between RT duration and outcomes was not observed. In pts receiving HD-CRT, longer RT duration was associated with improved DFS, which may have been due to a significant number of deaths at RT dose < 64.8 Gy. Supported by NCI U10 grants CA21661, CA180868, CA180822, CA37422. Clinical trial information: NCT00002631. [Table: see text]

Comparison and consensus guidelines for delineation of clinical target volume for CT- and MR-based brachytherapy in locally advanced cervical cancer

OBJECTIVE

To create and compare consensus clinical target volume (CTV) contours for computed tomography (CT) and 3-Tesla (3-T) magnetic resonance (MR) image-based cervical-cancer brachytherapy.

METHODS AND MATERIALS

Twenty-three experts in gynecologic radiation oncology contoured the same 3 cervical cancer brachytherapy cases: 1 stage IIB near-complete response (CR) case with a tandem and ovoid, 1 stage IIB partial response (PR) case with tandem and ovoid with needles, and 1 stage IB2 CR case with a tandem and ring applicator. The CT contours were completed before the MRI contours. These were analyzed for consistency and clarity of target delineation using an expectation maximization algorithm for simultaneous truth and performance level estimation (STAPLE), with κ statistics as a measure of agreement between participants. The conformity index was calculated for each of the 6 data sets. Dice coefficients were generated to compare the CT and MR contours of the same case.

RESULTS

For all 3 cases, the mean tumor volume was smaller on MR than on CT (P<.001). The κ and conformity index estimates were slightly higher for CT, indicating a higher level of agreement on CT. The Dice coefficients were 89% for the stage IB2 case with a CR, 74% for the stage IIB case with a PR, and 57% for the stage IIB case with a CR.

CONCLUSION

In a comparison of MR-contoured with CT-contoured CTV volumes, the higher level of agreement on CT may be due to the more distinct contrast medium visible on the images at the time of brachytherapy. MR at the time of brachytherapy may be of greatest benefit in patients with large tumors with parametrial extension that have a partial or complete response to external beam. On the basis of these results, a 95% consensus volume was generated for CT and for MR. Online contouring atlases are available for instruction at http://www.nrgoncology.org/Resources/ContouringAtlases/GYNCervicalBrachytherapy.aspx.

Interobserver variability in target definition for hepatocellular carcinoma with and without portal vein thrombus: radiation therapy oncology group consensus guidelines

PURPOSE

Defining hepatocellular carcinoma (HCC) gross tumor volume (GTV) requires multimodal imaging, acquired in different perfusion phases. The purposes of this study were to evaluate the variability in contouring and to establish guidelines and educational recommendations for reproducible HCC contouring for treatment planning.

METHODS AND MATERIALS

Anonymous, multiphasic planning computed tomography scans obtained from 3 patients with HCC were identified and distributed to a panel of 11 gastrointestinal radiation oncologists. Panelists were asked the number of HCC cases they treated in the past year. Case 1 had no vascular involvement, case 2 had extensive portal vein involvement, and case 3 had minor branched portal vein involvement. The agreement between the contoured total GTVs (primary + vascular GTV) was assessed using the generalized kappa statistic. Agreement interpretation was evaluated using Landis and Koch's interpretation of strength of agreement. The S95 contour, defined using the simultaneous truth and performance level estimation (STAPLE) algorithm consensus at the 95% confidence level, was created for each case.

RESULTS

Of the 11 panelists, 3 had treated >25 cases in the past year, 2 had treated 10 to 25 cases, 2 had treated 5 to 10 cases, 2 had treated 1 to 5 cases, 1 had treated 0 cases, and 1 did not respond. Near perfect agreement was seen for case 1, and substantial agreement was seen for cases 2 and 3. For case 2, there was significant heterogeneity in the volume identified as tumor thrombus (range 0.58-40.45 cc). For case 3, 2 panelists did not include the branched portal vein thrombus, and 7 panelists contoured thrombus separately from the primary tumor, also showing significant heterogeneity in volume of tumor thrombus (range 4.52-34.27 cc).

CONCLUSIONS

In a group of experts, excellent agreement was seen in contouring total GTV. Heterogeneity exists in the definition of portal vein thrombus that may impact treatment planning, especially if differential dosing is contemplated. Guidelines for HCC GTV contouring are recommended.

Anal carcinoma: impact of TN category of disease on survival, disease relapse, and colostomy failure in US Gastrointestinal Intergroup RTOG 98-11 phase 3 trial

PURPOSE

The long-term update of US GI Intergroup RTOG 98-11 anal cancer trial found that concurrent chemoradiation (CCRT) with fluorouracil (5-FU) plus mitomycin had a significant impact on disease-free survival (DFS) and overall survival (OS) compared with induction plus concurrent 5-FU plus cisplatin. The intent of the current analysis was to determine the impact of tumor node (TN) category of disease on survival (DFS and OS), colostomy failure (CF), and relapse (local-regional failure [LRF] and distant metastases [DM]) in this patient group.

METHODS AND MATERIALS

DFS and OS were estimated univariately by using the Kaplan-Meier method, and 6 TN categories were compared by the log-rank test (T2N0, T3N0, T4N0, T2N1-3, T3N1-3, and T4N1-3). Time to relapse and colostomy were estimated by the cumulative incidence method, and TN categories were compared using Gray's test.

RESULTS

Of 682 patients, 620 were analyzable for outcomes by TN category. All endpoints showed statistically significant differences among the TN categories of disease (OS, P<.0001; DFS, P<.0001; LRF, P<.0001; DM, P=.0011; CF, P=.01). Patients with the poorest OS, DFS, and LRF outcomes were those with T3-4N-positive (+) disease. CF was lowest for T2N0 and T2N+ (11%, 11%, respectively) and worst for the T4N0, T3N+, and T4N+ categories (26%, 27%, 24%, respectively).

CONCLUSIONS

TN category of disease has a statistically significant impact on OS, DFS, LRF, DM, and CF in patients treated with CCRT and provides excellent prognostic information for outcomes in patients with anal carcinoma. Significant challenges remain for patients with T4N0 and T3-4N+ categories of disease with regard to survival, relapse, and CF and lesser challenges for T2-3N0/T2N+ categories.

Upper abdominal normal organ contouring guidelines and atlas: a Radiation Therapy Oncology Group consensus

PURPOSE

To standardize upper abdominal normal organ contouring guidelines for Radiation Therapy Oncology Group (RTOG) trials.

METHODS AND MATERIALS

Twelve expert radiation oncologists contoured the liver, esophagus, gastroesophageal junction (GEJ), stomach, duodenum, and common bile duct (CBD), and reviewed and edited 33 additional normal organ and blood vessel contours on an anonymized patient computed tomography (CT) dataset. Contours were overlaid and compared for agreement using MATLAB (MathWorks, Natick, MA). S95 contours, defined as the binomial distribution to generate 95% group consensus contours, and normal organ contouring definitions were generated and reviewed by the panel.

RESULTS

There was excellent consistency and agreement of the liver, duodenal, and stomach contours, with substantial consistency for the esophagus contour, and moderate consistency for the GEJ and CBD contours using a Kappa statistic. Consensus definitions, detailed normal organ contouring recommendations and high-resolution images were developed.

CONCLUSIONS

Consensus contouring guidelines and a CT image atlas should improve contouring uniformity in radiation oncology clinical planning and RTOG trials.

Assessment of long-term rectal function in patients who received pelvic radiotherapy: a pooled North Central Cancer Treatment Group trial analysis, N09C1

PURPOSE

Pelvic radiotherapy (PRT) is known to adversely affect bowel function (BF) and patient well-being. This study characterized long-term BF and evaluated quality of life (QOL) in patients receiving PRT.

METHODS

Data from 252 patients were compiled from two North Central Cancer Treatment Group prospective studies, which included assessment of BF and QOL by the BF questionnaire (BFQ) and Uniscale QOL at baseline and 12 and 24 months after completion of radiotherapy. BFQ scores (sum of symptoms), Uniscale results, adverse-event incidence, and baseline demographic data were compared via t test, χ (2), Fisher exact, Wilcoxon, and correlation methodologies.

RESULTS

The total BFQ score was higher than baseline at 12 and 24 months (P < 0.001). More patients had five or more symptoms at 12 months (13 %) and 24 months (10 %) than at baseline (2 %). Symptoms occurring in greater than 20 % of patients at 12 and 24 months were clustering, stool-gas confusion, and urgency. Factors associated with worse BF were female sex, rectal or gynecologic primary tumors, prior anterior resection of the rectum, and 5-fluorouracil chemotherapy. Patients experiencing grade 2 or higher acute toxicity had worse 24-month BF (P values, <.001-.02). Uniscale QOL was not significantly different from baseline at 12 or 24 months, despite worse BFQ scores.

CONCLUSIONS

PRT was associated with worse long-term BF. Worse BFQ score was not associated with poorer QOL. Further research to characterize the subset of patients at risk of significant decline in BF is warranted.

Intraoperative Electron Beam Radiotherapy (IOERT) in the management of locally advanced or recurrent cervical cancer

Background

To report outcomes in women with locally recurrent or advanced cervical cancer who received intraoperative electron beam radiotherapy (IOERT) as a component of therapy.

Methods

From 1983 to 2010, 86 patients with locally recurrent (n = 73, 85%) or primary advanced (n = 13, 15%) cervical cancer received IOERT following surgery. Common surgeries included pelvic exenteration (n = 26; 30%) or sidewall resection (n = 22; 26%). The median IOERT dose was 15 Gy (range, 6.25-25 Gy). Sixty-one patients (71%) received perioperative external beam radiotherapy (EBRT; median dose, 45 Gy). Forty-one patients (48%) received perioperative chemotherapy.

Results

Median follow-up was 2.7 years (range, 0.1-25.5 years). Resections were classified as R0 (n = 35, 41%), R1 (n = 30, 35%), or R2 (n = 21, 24%). Cumulative incidences of central (within the IOERT field) and locoregional relapse at 3 years were 23 and 38%, respectively. The 3-year cumulative incidence of distant relapse was 43%. Median survival was 15 months, and 3-year Kaplan-Meier estimates of cause-specific (CSS) and overall survival (OS) were 31 and 25%, respectively. On multivariate analysis, pelvic exenteration (p = 0.02) and perioperative EBRT (p = 0.009) were associated with improved central control in patients with recurrent disease. Recurrence within 6 months of initial therapy was associated with reduced CSS (p = 0.001). Common IOERT-related toxicities included peripheral neuropathy (n = 16), ureteral stenosis (n = 4), and bowel fistula/perforation (n = 4). Eleven of 16 patients with neuropathy required long-term pain medication.

Conclusions

Long-term survival is possible with combined modality therapy including IOERT for advanced cervical cancer. Distant relapse is common, yet a significant number of patients experienced local progression in spite of aggressive treatment. In addition to consideration of disease- and treatment-related morbidity, other factors to be considered when selecting patients for this approach include the time interval from initial therapy to recurrence and whether the patient is able to receive perioperative EBRT and pelvic exenteration in addition to IOERT.

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.

Long-term update of US GI intergroup RTOG 98-11 phase III trial for anal carcinoma: survival, relapse, and colostomy failure with concurrent chemoradiation involving fluorouracil/mitomycin versus fluorouracil/cisplatin

PURPOSE

On initial publication of GI Intergroup Radiation Therapy Oncology Group (RTOG) 98-11 [A Phase III Randomized Study of 5-Fluorouracil (5-FU), Mitomycin, and Radiotherapy Versus 5-Fluorouracil, Cisplatin and Radiotherapy in Carcinoma of the Anal Canal], concurrent chemoradiation (CCR) with fluorouracil (FU) plus mitomycin (MMC) decreased colostomy failure (CF) when compared with induction plus concurrent FU plus cisplatin (CDDP), but did not significantly impact disease-free survival (DFS) or overall survival (OS) for anal canal carcinoma. The intent of the updated analysis was to determine the long-term impact of treatment on survival (DFS, OS, colostomy-free survival [CFS]), CF, and relapse (locoregional failure [LRF], distant metastasis) in this patient group.

PATIENTS AND METHODS

Stratification factors included sex, clinical node status, and primary size. DFS and OS were estimated univariately by the Kaplan-Meier method, and treatment arms were compared by log-rank test. Time to relapse and CF were estimated by the cumulative incidence method and treatment arms were compared by using Gray's test. Multivariate analyses used Cox proportional hazard models to test for treatment differences after adjusting for stratification factors.

RESULTS

Of 682 patients accrued, 649 were analyzable for outcomes. DFS and OS were statistically better for RT + FU/MMC versus RT + FU/CDDP (5-year DFS, 67.8% v 57.8%; P = .006; 5-year OS, 78.3% v 70.7%; P = .026). There was a trend toward statistical significance for CFS (P = .05), LRF (P = .087), and CF (P = .074). Multivariate analysis was statistically significant for treatment and clinical node status for both DFS and OS, for tumor diameter for DFS, and for sex for OS.

CONCLUSION

CCR with FU/MMC has a statistically significant, clinically meaningful impact on DFS and OS versus induction plus concurrent FU/CDDP, and it has borderline significance for CFS, CF, and LRF. Therefore, RT + FU/MMC remains the preferred standard of care.

RTOG 0529: a phase 2 evaluation of dose-painted intensity modulated radiation therapy in combination with 5-fluorouracil and mitomycin-C for the reduction of acute morbidity in carcinoma of the anal canal

PURPOSE

A multi-institutional phase 2 trial assessed the utility of dose-painted intensity modulated radiation therapy (DP-IMRT) in reducing grade 2+ combined acute gastrointestinal and genitourinary adverse events (AEs) of 5-fluorouracil (5FU) and mitomycin-C (MMC) chemoradiation for anal cancer by at least 15% compared with the conventional radiation/5FU/MMC arm from RTOG 9811.

METHODS AND MATERIALS

T2-4N0-3M0 anal cancer patients received 5FU and MMC on days 1 and 29 of DP-IMRT, prescribed per stage: T2N0, 42 Gy elective nodal and 50.4 Gy anal tumor planning target volumes (PTVs) in 28 fractions; T3-4N0-3, 45 Gy elective nodal, 50.4 Gy ≤ 3 cm or 54 Gy >3 cm metastatic nodal and 54 Gy anal tumor PTVs in 30 fractions. The primary endpoint is described above. Planned secondary endpoints assessed all AEs and the investigator's ability to perform DP-IMRT.

RESULTS

Of 63 accrued patients, 52 were evaluable. Tumor stage included 54% II, 25% IIIA, and 21% IIIB. In primary endpoint analysis, 77% experienced grade 2+ gastrointestinal/genitourinary acute AEs (9811 77%). There was, however, a significant reduction in acute grade 2+ hematologic, 73% (9811 85%, P=.032), grade 3+ gastrointestinal, 21% (9811 36%, P=.0082), and grade 3+ dermatologic AEs 23% (9811 49%, P<.0001) with DP-IMRT. On initial pretreatment review, 81% required DP-IMRT replanning, and final review revealed only 3 cases with normal tissue major deviations.

CONCLUSIONS

Although the primary endpoint was not met, DP-IMRT was associated with significant sparing of acute grade 2+ hematologic and grade 3+ dermatologic and gastrointestinal toxicity. Although DP-IMRT proved feasible, the high pretreatment planning revision rate emphasizes the importance of real-time radiation quality assurance for IMRT trials.

The clinical case for proton beam therapy

Over the past 20 years, several proton beam treatment programs have been implemented throughout the United States. Increasingly, the number of new programs under development is growing. Proton beam therapy has the potential for improving tumor control and survival through dose escalation. It also has potential for reducing harm to normal organs through dose reduction. However, proton beam therapy is more costly than conventional x-ray therapy. This increased cost may be offset by improved function, improved quality of life, and reduced costs related to treating the late effects of therapy. Clinical research opportunities are abundant to determine which patients will gain the most benefit from proton beam therapy. We review the clinical case for proton beam therapy. SUMMARY SENTENCE: Proton beam therapy is a technically advanced and promising form of radiation therapy.

Clinical outcomes and toxicity using stereotactic body radiotherapy (SBRT) for advanced cholangiocarcinoma

Background

To report single-institutional clinical outcomes and toxicity with SBRT for cholangiocarcinoma.

Methods

From March 2009 to July 2011, 10 patients with 12 unresectable primary (n = 6) or recurrent (n = 6) cholangiocarcinoma lesions underwent abdominal SBRT. Sites treated included liver (n = 10), abdominal lymph nodes (n = 1), and adrenal gland (n = 1). SBRT was delivered in three (n = 2) or five (n = 10) consecutive daily fractions over one week. The median prescription dose was 55 Gy (range, 45–60). Treatment response was graded by RECIST v.1.1, and toxicities were scored by CTCAE v.4.0. Data was analyzed using the Kaplan-Meier method to determine rates of local control (LC), freedom from distant progression (FFDM) and overall survival (OS).

Results

The median follow-up was 14 months (range, 2–26 months). LC, defined as freedom from progression within the SBRT field, was 100%, but four patients treated to intrahepatic sites experienced progression elsewhere in the liver. Estimates for FFDM at 6 and 12 months were 73% and 31%, respectively. Sites of disease relapse included liver (n = 3), liver and lymph nodes (n = 1), liver and lungs (n = 1), lymph nodes (n = 1), and mesentery (n = 1). OS estimates for the cohort at 6 and 12 months were 83% and 73%, respectively. The most common Grade ≥2 early toxicities were Grade 2 nausea and vomiting (n = 5) and gastrointestinal pain (n = 2). Late ≥2 toxicities included Grade 2 gastrointestinal pain (n = 3), Grade 3 biliary stenosis (n = 1), and Grade 5 liver failure (n = 1).

Conclusions

SBRT shows promise as an effective local therapy for properly-selected patients with cholangiocarcinoma. Further follow-up is needed to better quantify the risk of late complications associated with SBRT.

North Central Cancer Treatment Group phase II study of panitumumab (Pmab), chemotherapy, and external beam radiation (Chemo-RT) in patients with locally advanced (LA) pancreatic cancer

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Background: Epidermal growth factor inhibitors show some benefit in the treatment of advanced pancreatic cancer. A trial to evaluate the incorporation of Pmab into a conventional multimodality regimen and continuation as maintenance therapy was conducted in pts with LA disease.

Methods: Pts with ECOG PS 0-1, preserved organ function and tumor encompassed within standard radiation fields were eligible. Pmab 6 mg/kg on days 1, 15, 29 and continuous infusion 5-FU 225 mg/m2/d or capecitabine 825 mg/m2 were given with RT. Pts then received weekly gemcitabine 1000 mg/m2 and Pmab on days 1, 15 for three 4-week cycles. Maintenance Pmab was then continued for additional 6 months. RT consisted of 45 Gy to the tumor and regional nodes with a 5.4 Gy boost using conformal techniques. Primary endpoint of one-year survival (OS) with secondary endpoints progression-free survival (PFS), confirmed tumor response, and adverse events (at least possibly related) are reported.

Results: 51 pts (23 M: 28 F) were enrolled with a median age of 65 (range: 43-84). Twenty-two pts (43%) received at least 1 cycle of post-chemo-RT, while 29 patients only received chemo-RT. All 51 pts have ended treatment with pts going off study because of: progression (39%), adverse events (27%), refusal (25%), and other reasons (8%). Frequently occurring maximum grade 3/4 AEs across the entire treatment course (chemo-RT + post-chemo-RT chemo) are shown below. With a median follow-up of 12.3 months, survival at 12 months is 50.2% (95% CI: 37.9-66.5%), median survival 12.1 mos (95% CI: 6.8-15.9) and median PFS 7.4 mos (95% CI: 3.7-8.6). Confirmed response rate was 5.9% (1-CR, 2-PR).

Conclusions: The addition of Pmab to a conventional chemo-RT regimen provides benefit in terms of median survival. This is similar to reports of other EGFR inhibitors in LA disease. Adverse events, especially during the chemo-RT portion, were considerable and affected administration of subsequent systemic maintenance therapy.

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Intraoperative electron beam radiotherapy (IOERT) in the management of recurrent ovarian malignancies

OBJECTIVE

To investigate disease control, survival outcomes, and tolerance of intraoperative electron beam radiation therapy (IOERT) as a component of treatment for women with recurrent ovarian malignancies.

METHODS

From November 1987 to January 2009, 20 patients with recurrent ovarian malignancies received IOERT after maximal surgical cytoreduction. Areas treated included the pelvis (14), para-aortic nodes (6), or inguinal nodes (1). The median IOERT dose was 12.5 Gy (range, 10-22.5 Gy). Sixteen patients also received perioperative external beam radiotherapy as a component of treatment (median, 50 Gy; range, 20-54.3 Gy). All patients were followed prospectively for outcome and toxicity evaluation.

RESULTS

Median follow-up for surviving patients was 76.2 months (range, 1.5-175.8 months). The 5-year Kaplan-Meier estimate of local control was 59%, and central control (within the IOERT field) was 76%. All local relapses occurred in patients who had microscopic margin-positive resections. The 5-year freedom from distant relapse was 37%. The median disease-free interval after IOERT was 14 months. The median survival was 30 months, and the 5-year Kaplan-Meier estimate of survival was 49%. Six patients (29%) experienced grade 3 or higher toxicities, 2 of which (10%) were at least partly attributable to IOERT. Three patients experienced grade 1 or 2 peripheral neuropathy related to IOERT.

CONCLUSIONS

Combined modality therapy with external beam radiotherapy, surgery, and IOERT is an option for the treatment of localized recurrent ovarian cancer, with acceptable rates of in-field failure and toxicity. Durable disease control is possible in select women treated with this regimen.

Outcomes following surgery without radiotherapy for rectal cancer

BACKGROUND

This study determined survival and recurrence rates following curative resection of rectal cancer without radiotherapy.

METHODS

This was a retrospective review of the Mayo Clinic database of patients with rectal cancer treated with curative intent using surgery alone from 1990 to 2006. Patients who received neoadjuvant chemotherapy or radiation therapy and those who had any postoperative radiotherapy were excluded. Details were collected from the database and patient records using a protocol approved by the institutional review board.

RESULTS

Some 655 consecutive patients with rectal cancer treated with curative intent using surgery alone were identified; 397 had stage I disease, 125 stage II and 133 stage III. Four hundred and nine patients underwent anterior resection (AR) and 246 abdominoperineal resection (APR). Median follow-up was 62 months. The 5-year rate of local recurrence was 4·3 per cent, disease-free survival 90·0 per cent and cancer-specific survival 91·5 per cent. Stage-specific and all-stage disease-free survival did not differ significantly between AR and APR. The 5-year cumulative local recurrence rate was lower following AR than APR (3·6 versus 5·5 per cent; P = 0·321). There were only two patients with positive margins and type of operation was not significant on multivariable analysis.

CONCLUSION

Well-performed, standardized APRs have similar local recurrence to AR. Radiation therapy may not confer much additional benefit.