Clinical and Dosimetric Impact of 2D kV Motion Monitoring and Intervention in Liver Stereotactic Body Radiation Therapy

Purpose

Positional errors resulting from motion are a principal challenge across all disease sites in radiation therapy. This is particularly pertinent when treating lesions in the liver with stereotactic body radiation therapy (SBRT). To achieve dose escalation and margin reduction for liver SBRT, kV real-time imaging interventions may serve as a potential solution. In this study, we report results of a retrospective cohort of liver patients treated using real-time 2D kV-image guidance SBRT with emphasis on the impact of (1) clinical workflow, (2) treatment accuracy, and (3) tumor dose.

Methods and Materials

Data from 33 patients treated with 41 courses of liver SBRT were analyzed. During treatment, planar kV images orthogonal to the treatment beam were acquired to determine treatment interventions, namely treatment pauses (ie, adequacy of gating thresholds) or treatment shifts. Patients were shifted if internal markers were >3 mm, corresponding to the PTV margin used, from the expected reference condition. The frequency, duration, and nature of treatment interventions (ie, pause vs shift) were recorded, and the dosimetric impact associated with treatment shifts was estimated using a machine learning dosimetric model.

Results

Of all fractions delivered, 39% required intervention, which took on average 1.9 ± 1.6 minutes and occurred more frequently in treatments lasting longer than 7 minutes. The median realignment shift was 5.7 mm in size, and the effect of these shifts on minimum tumor dose in simulated clinical scenarios ranged from 0% to 50% of prescription dose per fraction.

Conclusion

Real-time kV-based imaging interventions for liver SBRT minimally affect clinical workflow and dosimetrically benefit patients. This potential solution for addressing positional errors from motion addresses concerns about target accuracy and may enable safe dose escalation and margin reduction in the context of liver SBRT.

Association of Radiotherapy Duration With Clinical Outcomes in Patients With Esophageal Cancer Treated in NRG Oncology Trials: A Secondary Analysis of NRG Oncology Randomized Clinical Trials

Importance

For many types of epithelial malignant neoplasms that are treated with definitive radiotherapy (RT), treatment prolongation and interruptions have an adverse effect on outcomes.

Objective

To analyze the association between RT duration and outcomes in patients with esophageal cancer who were treated with definitive chemoradiotherapy (CRT).

Design, Setting, and Participants

This study was an unplanned, post hoc secondary analysis of 3 prospective, multi-institutional phase 3 randomized clinical trials (Radiation Therapy Oncology Group [RTOG] 8501, RTOG 9405, and RTOG 0436) of the National Cancer Institute-sponsored NRG Oncology (formerly the National Surgical Adjuvant Breast and Bowel Project, RTOG, and Gynecologic Oncology Group). Enrolled patients with nonmetastatic esophageal cancer underwent definitive CRT in the trials between 1986 and 2013, with follow-up occurring through 2014. Data analyses were conducted between March 2022 to February 2023.

Exposures

Treatment groups in the trials used standard-dose RT (50 Gy) and concurrent chemotherapy.

Main Outcomes and Measures

The outcomes were local-regional failure (LRF), distant failure, disease-free survival (DFS), and overall survival (OS). Multivariable models were used to examine the associations between these outcomes and both RT duration and interruptions. Radiotherapy duration was analyzed as a dichotomized variable using an X-Tile software to choose a cut point and its median value as a cut point, as well as a continuous variable.

Results

The analysis included 509 patients (median [IQR] age, 64 [57-70] years; 418 males [82%]; and 376 White individuals [74%]). The median (IQR) follow-up was 4.01 (2.93-4.92) years for surviving patients. The median cut point of RT duration was 39 days or less in 271 patients (53%) vs more than 39 days in 238 patients (47%), and the X-Tile software cut point was 45 days or less in 446 patients (88%) vs more than 45 days in 63 patients (12%). Radiotherapy interruptions occurred in 207 patients (41%). Female (vs male) sex and other (vs White) race and ethnicity were associated with longer RT duration and RT interruptions. In the multivariable models, RT duration longer than 45 days was associated with inferior DFS (hazard ratio [HR], 1.34; 95% CI, 1.01-1.77; P = .04). The HR for OS was 1.33, but the results were not statistically significant (95% CI, 0.99-1.77; P = .05). Radiotherapy duration longer than 39 days (vs ≤39 days) was associated with a higher risk of LRF (HR, 1.32; 95% CI, 1.06-1.65; P = .01). As a continuous variable, RT duration (per 1 week increase) was associated with DFS failure (HR, 1.14; 95% CI, 1.01-1.28; P = .03). The HR for LRF 1.13, but the result was not statistically significant (95% CI, 0.99-1.28; P = .07).

Conclusions and Relevance

Results of this study indicated that in patients with esophageal cancer receiving definitive CRT, prolonged RT duration was associated with inferior outcomes; female patients and those with other (vs White) race and ethnicity were more likely to have longer RT duration and experience RT interruptions. Radiotherapy interruptions should be minimized to optimize outcomes.

Use of the Toxicity Index in Evaluating Adverse Events in Anal Cancer Trials: Analysis of RTOG 9811 and RTOG 0529

Novel toxicity metrics that account for all adverse event (AE) grades and the frequency of may enhance toxicity reporting in clinical trials. The Toxicity Index (TI) accounts for all AE grades and frequencies for categories of interest. We evaluate the feasibility of using the TI methodology in 2 prospective anal cancer trials and to evaluate whether more conformal radiation (using Intensity Modulated Radiation Therapy) results in improved toxicity as measured by the TI. Patients enrolled on NRG/RTOG 0529 or nonconformal RT enrolled on the 5-Fluorouracil/Mitomycin arm of NRG/RTOG 9811 were compared using the TI. Patients treated on NRG/RTOG 0529 had lower median TI compared with patients treated with nonconformal RT on NRG/RTOG 9811 for combined GI/GU/Heme/Derm events (3.935 vs 3.996, P=0.014). The TI methodology is a feasible method to assess all AEs of interest and may be useful as a composite metric for future efforts aimed at treatment de-escalation or escalation.

Practical Implementation of Emergent After-Hours Radiation Treatment Process Using Remote Treatment Planning on Optimized Diagnostic CT Scans

The purpose of this report is to present the implementation of a process for after-hours radiation treatment (RT) utilizing remote treatment planning based on optimized diagnostic computed tomography (CT) scans for the urgent palliative treatment of inpatients. A standardized operating procedure was developed by an interprofessional panel to improve the quality of after-hours RT and minimize the risk of treatment errors. A new diagnostic CT protocol was created that could be performed after-hours on hospital scanners and would ensure a reproducible patient position and adequate field of view. An on-call structure for dosimetry staff was created utilizing remote treatment planning. The optimized CT protocol was developed in collaboration with the radiology department, and a novel order set was created in the electronic health system. The clinical workflow begins with the radiation oncologist notifying the on-call team (therapist, dosimetrist, and physicist) and obtaining an optimized diagnostic CT scan on a hospital-based scanner. The dosimetrist remotely creates a plan; the physicist checks the plan; and the patient is treated. Plans are intentionally simple (parallel opposed fields, symmetric jaws) to expedite care and reduce the risk of error. Education on the new process was provided for all relevant staff. Our process was successfully implemented with the use of an optimized CT protocol and remote treatment planning. This approach has the potential to improve the quality and safety of emergent after-hours RT by better approximating the normal process of care.

Association of pretreatment CA19-9 with survival after 3-fraction SBRT for locally advanced pancreatic cancer: Results from a phase I dose-escalation trial

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Background: The optimal dose and fractionation scheme for stereotactic body radiotherapy (SBRT) is unknown. The biologic effects of ultra-high doses per fraction (>8Gy) are theoretical, but may include eliciting an effect on the endothelial cells of the tumor vasculature which could improve treatment response. This study aimed to determine the safety and maximally tolerated dose of 3-fraction SBRT for locally advanced pancreatic cancer (LAPC). Methods: A multi-site phase 1 dose escalation trial was conducted from March 2016 to April 2019 at Memorial Sloan Kettering Cancer Center (NCT02643498) and University of Colorado (NCT02873598). Patients with localized histologically confirmed pancreatic adenocarcinoma deemed unresectable on multidisciplinary review without distant progression following induction chemotherapy for ≥ 2 months were eligible. Patients received 3-fraction LINAC-based SBRT at 3 dose levels, 27Gy, 30Gy and 33Gy following a modified 3+3 design, allowing for enrollment of additional patients at the last dose level during the 90-day observation period, provided no dose-limiting toxicities (DLTs) were observed. DLTs were defined as ≥ Grade 3 treatment-related GI toxicity within 90 days of RT by CTCAE v.4. The secondary endpoints were overall survival (OS), local progression-free and distant metastasis-free survival (LPFS and DMFS, respectively). Univariate analysis using log-rank test was performed to identify factors associated with OS. Results: Twenty-three evaluable patients were enrolled, including 8 patients at 27Gy, 8 patients at 30Gy and 7 patients at 33Gy. The median age was 67 years (range 52 - 79), 9 patients (39%) were male, all were stage IIIwith a median tumor size of 3.5cm (range, 1.0 - 6.4) and CA19-9 of 60U/mL (range, <1 - 4880). All received chemotherapy for a median of 4.0 months (range 2.5 -11.4). There were no grade ≥ 3 abdominal pain, dyspepsia, diarrhea, nausea, vomiting, or gastrointestinal hemorrhage. Four patients underwent resections (pancreaticoduodenectomy=3, Appleby=1). Twelve-month rates of OS, DMFS and LPFS were 45.8 %, 37.7% and 53.0%, respectively. On univariate analysis, CA19-9 (HR=0.2365, 95%CI 0.07999 to 0.6990), but not dose level, size, N stage, tumor location, duration of chemotherapy were associated with OS. Twelve-month OS for patients with CA19-9 ≤ 60U/mL vs > 60U/mL were 80% vs 27% (p=0.0023). Conclusions: For select LAPC patients, dose escalation to the target dose of 33Gy in 3 fractions resulted in no DLTs and disease outcomes comparable to conventional RT. Lower pre-SBRT CA19-9 values were associated with improved OS and could help identify patients most likely to benefit from local therapies. Continued exploration of (ultra)hypofractionated schemes to maximize tumor control while enabling efficient integration of RT with systemic therapy is warranted. Clinical trial information: NCT02643498/NCT02873598.

Long-Term Outcomes of NRG Oncology/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 Anal Canal Cancer

PURPOSE

A multi-institutional phase 2 trial assessed long-term outcomes of dose-painted intensity modulated radiation therapy (IMRT) with 5-fluorouracil (5FU) and mitomycin-C (MMC) for anal canal cancer.

METHODS AND MATERIALS

T2-4N0-3M0 anal cancers received 5FU (1000 mg/m²/d, 96-hour infusion) and MMC (10 mg/m² bolus) on days 1 and 29 of dose-painted IMRT prescribed as follows: T2N0 = 42 Gy elective nodal and 50.4 Gy anal tumor planning target volumes, 28 fractions; T3-4N0-3 = 45Gy elective nodal, 50.4 Gy ≤3 cm and 54 Gy >3cm metastatic nodal and 54 Gy anal tumor planning target volumes, 30 fractions. Local-regional failures, distant metastases, and colostomy failures were assessed using the cumulative incidence method, and disease-free survival, overall survival, and colostomy-free survival were assessed using the Kaplan-Meier method. Late effects were scored using National Cancer Institute-Common Terminology Criteria for Adverse Events v3.

RESULTS

Of 52 patients, 54% were stage II, 25% were stage IIIA, and 21% were stage IIIB. Median follow-up was 7.9 years (min-max, 0.02-9.2 years). Local-regional failure, colostomy failures, distant metastases, overall survival, disease-free survival, and colostomy-free survival at 5 years are 16% (95% confidence interval [CI], 7%-27%), 10% (95% CI, 4%-20%), 16% (95% CI, 7%-27%), 76% (95% CI, 61%-86%), 70% (95% CI, 56%-81%), and 74% (95% CI, 59%-84%); and at 8 years they are 16% (95% CI, 7%-27%), 12% (95% CI, 5%-23%), 22% (95% CI, 12%-34%), 68% (95% CI, 53%-79%), 62% (95% CI, 47%-74%) and 66% (95% CI, 51%-77%), respectively. Eight patients experienced local-regional failure, with 5 patients having persistent disease at 12 weeks. No isolated nodal failures occurred in the microscopic elective nodal volumes. Six patients required colostomy-5 for local-regional salvage and 1 for a temporary ostomy for anorectal dysfunction. Rates of late adverse events included: 28 patients (55%) with grade 2, 8 patients (16%) with grade 3, 0 patients with grade 4, and 2 patients (4%) with grade 5 events (sinus bradycardia and myelodysplasia, possibly owing to chemotherapy). Only 11 patients reported grade 1 to 3 sexual dysfunction.

CONCLUSIONS

Dose-painted IMRT with 5FU/MMC for the treatment of anal canal cancer yields comparable long-term efficacy as conventional radiation cohorts. Enhanced normal tissue protection lowered rates of grade 3 and higher late effects without compromising pelvic tumor control.

Use of Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer: Initial Results From the Pembrolizumab Arm of a Phase 2 Randomized Clinical Trial

Importance

Total neoadjuvant therapy (TNT) is often used to downstage locally advanced rectal cancer (LARC) and decrease locoregional relapse; however, more than one-third of patients develop recurrent metastatic disease. As such, novel combinations are needed.

Objective

To assess whether the addition of pembrolizumab during and after neoadjuvant chemoradiotherapy can lead to an improvement in the neoadjuvant rectal (NAR) score compared with treatment with FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin) and chemoradiotherapy alone.

Design, Setting, and Participants

In this open-label, phase 2, randomized clinical trial (NRG-GI002), patients in academic and private practice settings were enrolled. Patients with stage II/III LARC with distal location (cT3-4 ≤ 5 cm from anal verge, any N), with bulky disease (any cT4 or tumor within 3 mm of mesorectal fascia), at high risk for metastatic disease (cN2), and/or who were not candidates for sphincter-sparing surgery (SSS) were stratified based on clinical tumor and nodal stages. Trial accrual opened on August 1, 2018, and ended on May 31, 2019. This intent-to-treat analysis is based on data as of August 2020.

Interventions

Patients were randomized (1:1) to neoadjuvant FOLFOX for 4 months and then underwent chemoradiotherapy (capecitabine with 50.4 Gy) with or without intravenous pembrolizumab administered at a dosage of 200 mg every 3 weeks for up to 6 doses before surgery.

Main Outcomes and Measures

The primary end point was the NAR score. Secondary end points included pathologic complete response (pCR) rate, SSS, disease-free survival, and overall survival. This report focuses on end points available after definitive surgery (NAR score, pCR, SSS, clinical complete response rate, margin involvement, and safety).

Results

A total of 185 patients (126 [68.1%] male; mean [SD] age, 55.7 [11.1] years) were randomized to the control arm (CA) (n = 95) or the pembrolizumab arm (PA) (n = 90). Of these patients, 137 were evaluable for NAR score (68 CA patients and 69 PA patients). The mean (SD) NAR score was 11.53 (12.43) for the PA patients (95% CI, 8.54-14.51) vs 14.08 (13.82) for the CA patients (95% CI, 10.74-17.43) (P = .26). The pCR rate was 31.9% in the PA vs 29.4% in the CA (P = .75). The clinical complete response rate was 13.9% in the PA vs 13.6% in the CA (P = .95). The percentage of patients who underwent SSS was 59.4% in the PA vs 71.0% in the CA (P = .15). Grade 3 to 4 adverse events were slightly increased in the PA (48.2%) vs the CA (37.3%) during chemoradiotherapy. Two deaths occurred during FOLFOX: sepsis (CA) and pneumonia (PA). No differences in radiotherapy fractions, FOLFOX, or capecitabine doses were found.

Conclusions and Relevance

Pembrolizumab added to chemoradiotherapy as part of total neoadjuvant therapy was suggested to be safe; however, the NAR score difference does not support further study.

Trial Registration

ClinicalTrials.gov Identifier: NCT02921256.

A single-institution experience using total neoadjuvant therapy to treat locally advanced rectal cancer

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Background: The management of locally advanced rectal cancer has historically included preoperative chemoradiation followed by surgery and then adjuvant chemotherapy. Recently there has been an increasing utilization of preoperative chemotherapy in addition to standard chemoradiation, a strategy known as total neoadjuvant therapy (TNT). TNT has been offered to patients at the University of Colorado Cancer Center since 2015. Methods: Records of all patients presenting to the University of Colorado colorectal multidisciplinary clinic since 2015 were screened for treatment with TNT. Data collected on these patients included demographic information, diagnosis and initial staging, preoperative treatment received, and surgical outcomes including treatment response and pathological stage. TNT included preoperative chemotherapy with oxaliplatin combined with either 5-FU (FOLFOX) or capecitabine (CAPOX) as well as chemoradiation, generally given with concurrent capecitabine. Patients then underwent surgical resection; if a complete clinical response was achieved with TNT, non-operative management (NOM) was offered. Results: A total of 81 patients thus far have undergone TNT followed by resection or, if complete clinical response and preferred by the patient, NOM. The mean age of patients was 56 years, ranging from 23 to 87, and 60% of patients were male. The majority of patients (67) had stage III disease at presentation while 1 had stage 1 (T2N0) disease, 11 had stage II disease and 2 patients had oligometastatic disease. Ultimately 13 patients (16%) opted for non-operative management after being found to have a complete clinical response following TNT. Of the 68 patients who underwent surgical resection, 21 (31%) had a pathological complete response, with another 14 (21%) with near-complete response. 28 patients (41%) had a partial treatment response and 5 (7%) had no treatment response. In total, the rate of complete clinical or pathologic response was 42%. Treatment was overall well-tolerated with 90% of patients receiving the full planned dose of radiation and 98% of patients completing all planned cycles of chemotherapy, though most of them with typical dose reductions needed. Of the patients who underwent surgery, 49 (72%) had low anterior resection and 19 (28%) had an abdominoperineal resection. Of patients with temporary ileostomies, 85% of them had their ileostomy reversed within 10 weeks of surgery. Conclusions: Treatment of locally advanced rectal cancer by a total neoadjuvant approach is well-tolerated and results in a high rate of clinical and pathological complete response.

The role of neoadjuvant chemotherapy in elderly patients with borderline or locally advanced pancreatic cancer: Is it safe and feasible?

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Background: For borderline resectable (BRPC) or locally advanced pancreatic cancer (LAPC), neoadjuvant (NAT) FOLFIRINOX or gemcitabine plus nab-paclitaxel (GnP) are standard treatment options and these regimens have shown a survival advantage over single-agent gemcitabine. However, the role of these modern therapeutic regimens in elderly patients is debatable. In this analysis, we evaluated the outcomes of neoadjuvant treatment (NAT) with combination chemotherapy in elderly patients. Methods: 230 consecutive patients who underwent neoadjuvant treatment for BRPC/LAPC discussed and planned for NAT at the University of Colorado Cancer Center from January 2011 to March 2019 were reviewed. 214 patients who received FOLFIRINOX (n = 143) or GnP (n = 71) were eligible for analysis. We divided all patients into three groups ( < 70, 70-74, ≥75 years) and compared the short-term and long-term outcomes. Results: Of 214 patients, patients < 70 (n = 147) received FOLFIRINOX more frequently than the other groups (p < 0.001): FOLFIRINOX: 115 cases, GnP: 32 cases, 70-74 years (n = 33): FOLFIRINOX: 15 cases, GnP: 18 cases, and ≥75 years (n = 34): FOLFIRINOX: 13 cases, GnP: 21 cases. Resection rates were not statistically different between three groups ( < 70: 62%, 70-74: 70%, ≥75 years: 56%, p = 0.504). There was a slight trend towards worse survival in the two older groups (Median Survival Time [MST]: < 70: 23.2 mo., 70-74: 19.5 mo., ≥75 years: 17.6 mo., p = 0.075) The FOLFIRINOX group was superior to GnP group in all three groups (MST: < 70: 25.6 vs 18.2 mo., p = 0.017; 70-74: 33.2 vs 16.1mo., p = 0.029; ≥75 years: not reached vs 16.1 mo., p = 0.135). There were no toxic deaths or 30 day mortality after pancreatectomy in the study population. Conclusions: Neoadjuvant combination chemotherapy regimens were safe and feasible for elderly patients. Neoadjuvant therapy with FOLFIRINOX was associated with a survival advantage vs GnP and is an good option for fit and elderly patients ≥75 years.

An assessment of dose intensity of the TNT approach on outcomes in locally advanced rectal cancer

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Background: Patients with clinical stage II or III locally advanced rectal cancer may be treated with the total neoadjuvant therapy (TNT) approach; chemotherapy with 4 mths of FOLFOX followed by chemoradiation (chemo/XRT) with capecitabine for 5 wks administered before surgery. We hypothesized that full dose intensity is not necessary for treatment benefit. Methods: A retrospective chart review was conducted on patients with newly diagnosed rectal cancer recommended to receive TNT by the multidisciplinary (multiD) colorectal cancer tumor board at the University of Colorado Cancer Center (UCCC). The primary objective was to evaluate dose intensity of TNT and its impact on response assessed by biopsy and/or imaging (MRI). Results: Between January 31, 2016 and January 31, 2019, 80 patients were recommended the TNT approach for cancer management by the multiD team. Of those, 48 completed their neoadjuvant treatment at UCCC and were included in the analysis. The average age was 55 years (range 23-80) and 61% were male. Thirty-one patients had an ECOG of 0 and 17 had an ECOG of 1. Overall responses were 44% complete response (CR, n = 21), 15% near complete response (nCR, n = 7), 35% partial response (PR, n = 17), and 6% no response (NR, n = 3). See Table for responses seen by dose intensity for chemotherapy. Two patients did not receive their full planned XRT course, and 9 patients had their capecitabine doses held/decreased during chemoradiation. Conclusions: This single center retrospective analysis of patients receiving the TNT approach for rectal cancer provides data supporting that achieving full dose intensity is not necessary to achieve treatment benefit.

[Table: see text]

Endoscopic Ultrasound Placement of Preloaded Fiducial Markers Shortens Procedure Time Compared to Back-Loaded Markers

BACKGROUND & AIMS

Fiducial markers are inert radiopaque gold or carbon markers implanted in or near pancreatic tumor to demarcate areas for image-guided radiation therapy. Endoscopic ultrasound (EUS) pre-loaded fiducial needles (PLNs) have been developed to circumvent technical issues associated with traditional back-loaded fiducials (BLNs). We performed a randomized controlled trial to compare procedure times in patients with pancreatic adenocarcinoma undergoing EUS-guided placement of BLNs vs PLNs.

METHODS

In a prospective study, 44 patients with pancreatic adenocarcinoma referred for fiducial marker placement at 2 tertiary care centers were assigned to groups that received PLNs (n = 22) or BLNs (n = 22); each group had the same proportion of patients with tumors of different locations (head or neck vs body or tail).The procedure was standardized among all endoscopists and placement of a minimum of 3 markers inside the tumor was defined as technical success. The times for procedure and fiducial placement were recorded, total number of fiducial markers used documented, and grade of procedure difficulty ranked by passing the needle or deploying the fiducials. Other recorded variables included tumor characteristics, fluoroscopy use, and the number of fiducials clearly seen by EUS and fluoroscopy. The primary aim was to compare the duration of EUS-guided fiducial insertion of BLNs vs PLNs.

RESULTS

The median placement time was significantly shorter in the PLN group (9 min) than the BLN group (16 min) (P < .001). However, the 44% reduction in time did not reach pre-specified levels (≥60%). Similar results were found after stratifying by tumor location. Deployment of BLNs was easier than deployment of PLNs (P = .03). There was no significant difference between groups in technical success, number of fiducials placed, EUS or fluoroscopic visualization, or adverse events. During simulation computed tomography and image-guided radiation therapy, there was no difference between groups in visualization of fiducials, migration rate, or accuracy of placement.

CONCLUSIONS

In a randomized controlled trial of 44 patients with pancreatic adenocarcinoma, we found EUS-guided placement of PLNs to require less time and produce similar results compared with BLNs. Further refinements in PLN delivery system are needed to increase the ease of deployment. Clinicaltrials.gov no: NCT02332863.

QIM19-130: Quality Improvement Project to Standardize a Prehabilitation Pathway for Patients With Esophageal Cancer Receiving Neoadjuvant Chemoradiation

Background: At our institution, the standard treatment recommendation for esophageal cancer patients with stage IB–IIIB disease is for neoadjuvant chemoradiation per the CROSS regimen prior to surgery. This regimen can be difficult for patients to tolerate, and they may be unable to receive full dose therapy without treatment dose reductions and delays. Methods: We conducted a quality improvement (QI) project, STRENGTH (Seeking to Reactivate Esophageal and Gastric Treatment Health), to implement supportive care interventions in the prehabilitation phase of neoadjuvant treatment. Our QI program included a standardized chemotherapy order template with supportive care interventions implemented at specific time points. Following implementation of the STRENGTH pathway, a retrospective QI analysis assessed an equal number of patients in the pre-STRENGTH and STRENGTH group for chemotherapy and radiation therapy dose intensities, as well as treatment outcomes. Results: During the pre-STRENGTH period, patients received an average of 5 chemotherapy treatments (range, 2–6), with an average relative dose intensity of 91.8% for carboplatin and 86.7% for paclitaxel. During the STRENGTH period, patients received an average of 6 (range, 5–8) chemotherapy treatments, with an average relative dose intensity of 111.4% for carboplatin and 112.9% for paclitaxel. In the pre-STRENGTH group, one patient did not complete their planned radiation dose due to nausea, vomiting, and dehydration. All patients in the STRENGTH group received their planned radiation dose. In the STRENGTH group, there is a trend of improved pathologic response, longer progression-free survival, and shortened time to surgery. Conclusion: Implementation of the STRENGTH pathway improved chemotherapy dose intensity, with potentially improved oncologic outcomes in the STRENGTH group. We plan to further optimize the STRENGTH program with implementation of standardized dose reduction and delay protocols for both chemotherapy and radiation, and assess the effects of STRENGTH interventions on patient quality of life.

Anal Cancer in the Era of Dose Painted Intensity Modulated Radiation Therapy: Implications for Regional Nodal Therapy

Since the initial development of 5-fluorouracil and mitomycin as a standard of care platform for definitive anal cancer chemoradiotherapy, multiple studies have evaluated the optimal chemotherapy regimen, and radiotherapy technique. Refinements in treatment technique have taken place during an era of improved diagnostic imaging, including incorporation of FDG-PET, with implications for a possible stage migration effect. This has introduced an opportunity to develop stage-specific recommendations for primary tumor, involved nodal, and elective nodal irradiation dose. Elective nodal irradiation remains standard given the low rates of elective nodal failure with current practice, although may be subject to evolving controversy for patients with early stage disease. In this review, development of the current standard of care for anal cancer chemoradiotherapy is reviewed in the context of modern staging and dose-painted radiotherapy treatment techniques.

Impact of neoadjuvant chemotherapy and stereotactic body radiation therapy (SBRT) on R0 resection rate for borderline resectable and locally advanced pancreas cancer

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Background: Management for borderline resectable pancreas cancer (BRPC) and locally advanced pancreas cancer (LAPC) is controversial. Multiagent chemotherapy (CT) followed by SBRT may allow for tumor downstaging and the ability to perform an R0 resection. Methods: We retrospectively evaluated BRPC and LAPC patients (pts) treated on our multidisciplinary treatment pathway. Pts underwent 2-3 months of CT. Pts without systemic progression received five fractions of SBRT, delivered every other day, to a dose of 30-33 Gy. After restaging, pts underwent surgery if resectable. Overall survival (OS), distant metastasis free survival (DMFS) and local progression free survival (LPFS) were estimated and compared by Kaplan-Meier and log-rank methods. Results: We identified 80 pts with BRPC (65) or LAPC (15) treated with neoadjuvant CT + SBRT between 2011-2017. Median follow up was 20 months. CT primarily included FOLFIRINOX (65%) and gemcitabine/nab-paclitaxel (30%). Of pts completing CT + SBRT, 67 (84%) went to surgery and 53 (79%) of those pts underwent definitive surgery including seven LAPC patients. The remaining 14 pts underwent palliative or exploratory surgery due to intraoperative metastases (43%) or vascular involvement (57%). Of pts undergoing definitive surgery, 51 had R0 resection (96%) and 5 (9%) had a complete pathologic response (PR) to CT + SBRT. The R0 resection rate of the cohort was 64%. OS was 24.5 months. Pts with a complete or marked (14%) PR had significantly better OS than those with a moderate (40%) PR (41.3 vs 30 months, p = 0.04) and pts unable to undergo definitive surgery (18.2 months, p < 0.001). Zero of 11 pts who had a marked or complete PR had local progression, significant compared to those with moderate PR (p = 0.012). DMFS between these two groups was not statistically significantly different. Conclusions: Neoadjuvant CT + SBRT are associated with favorable PR rates and R0 resection rates. Marked or complete PR was associated with improved LPFS and OS compared to moderate PR and pts who did not undergo definitive surgery. DMFS was not significantly different between complete and marked PR compared to those with moderate PR.

Impact of multidisciplinary management in the diagnosis and treatment of neuroendocrine tumors (NET)

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Background: The incidence and prevalence of NETs is increasing and diagnosis and pathologic evaluation of NETs is complex. Given the new advances in local and systemic therapies, multidisciplinary management models have been suggested to assist in treatment decisions. However, scientific data showing definite change in management with multidisciplinary clinic (MDC) review is lacking. We aim to address this need in this study. Methods: 113 GI-NET patients from 2012-18 were reviewed from a dedicated MDC where patients are seen simultaneously by multiple subspecialties, and data on patient characteristics, radiology, tumor pathology and treatment strategies were collected. Change in diagnosis was defined as any change in radiographic or pathologic findings that resulted in a change in the tumor type, grade, site or stage of cancer. Change in management was defined as any recommended change in treatment approach for NETs compared to the prior treatment plan. For patients who did not have a prior treatment plan or were seen directly at MDC, a change of management was considered as yes only if there was a change in diagnosis post MDC. Results: The mean age of patients evaluated was 61, with locally advanced or metastatic disease seen in 81% of patients. Small bowel and pancreatic NETs were the most common primaries (36% each). Significant proportion of NETs were well-differentiated (72%) with < 2 mitosis/10 HPF (47.3%) and Ki-67 of < 3% (36%). Patients were referred to MDC at an average of 2.5 years from diagnosis, with 23% having the MDC as their first visit. 40% had prior resection of primary, 25% were on somatostatin analogues (SSAs) previously and 9% of patients had received prior liver directed therapy (LDT). A significant proportion of patients had change in diagnosis post MDC evaluation: change in site (7%), stage of disease (7%), tumor type (3.5%) and grade (0.1%). A change in management was recommended in 50% of patients, with SSAs recommended in 43.8%, surgery in 25.4% and LDT in 17.5% of the patients. Conclusions: The use of a dedicated MDC to manage NETs had a substantial impact in change in management in a significant percentage of patients evaluated. MDC care for patients diagnosed with NET is recommended for optimal management.

Impact of radiation dose during neoadjuvant chemoradiation on postoperative complications in esophageal (EC) and gastroesophageal junction cancers (GEJC)

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Background: Neoadjuvant chemoradiation (nCRT) followed by resection is standard of care for operable stage II-III EC and GEJC; however, it can be associated with significant risk of postoperative complications (POC). The CROSS study group reported no increase in POC severity with nCRT using 41.4 Gy compared to surgery alone as defined by the Comprehensive Complication Index (CCI). We applied the CCI metric to evaluate the impact of nCRT radiation dose of < 50 Gy vs. ≥ 50 Gy on POC rates and compared to the CROSS rates. Methods: We retrospectively reviewed 82 pts (2004-2016) with EC or GEJC treated with nCRT followed by resection at our institution. 29 (35%) pts were treated with < 50 Gy (range 39.6-46.8 Gy) and 53 (65%) were treated with ≥ 50 Gy (range 50.0-52.5 Gy) delivered using IMRT/VMAT (41%), 3D-CRT (46%), or tomotherapy IMRT (12%). Concurrent chemotherapy were carboplatin/paclitaxel (59%), cisplatin/5-FU (17%), or other (24%). Resection was performed by Ivor Lewis esophagectomy (67%), esophagogastrectomy (14%), or trans-hiatal approach (11%). POC within 30 days were graded using the Clavien-Dindo scale and CCI scores were computed and compared between the two dose groups and with the CROSS nCRT group. Results: CCI scores and complication rates between our < 50 Gy and ≥ 50 Gy groups were not significantly different. Assuming a normal distribution of the CROSS CCI scores, there was no significant difference in CCI scores between the CROSS study nCRT, < 50 Gy, or ≥ 50 Gy groups. Rates of pulmonary complications were greater in the CROSS study. Conclusions: In highly selected EC and GEJC pts, definitive nCRT radiation doses do not appear to increase POC rates. Thus, 50 Gy can likely be delivered without increasing toxicity while also achieving a definitive dose for pts not able or willing to undergo subsequent surgery. [Table: see text]

Pilot Prehabilitation Program for Patients With Esophageal Cancer During Neoadjuvant Therapy and Surgery

BACKGROUND

Locally advanced esophageal cancer is often treated with neoadjuvant therapy followed by surgery. Many patients present with or experience clinical deconditioning during neoadjuvant therapy. Prehabilitation programs in other areas of surgery have demonstrated improved postoperative outcomes. The aims of this study were to evaluate the feasibility of a pilot prehabilitation program and determine preliminary effects on surgical and cancer-related outcomes.

METHODS

A retrospective review of patients treated at a single institution with resectable esophageal cancer was performed (n = 22). Patients in the prehabilitation group received protocol-structured intervention in several clinical domains including nutrition, psychosocial support, and physical exercise.

RESULTS

Clinical stage and comorbidities were well matched between groups. The structured prehabilitation program was feasible and well received by participants. Fewer patients required admission during neoadjuvant therapy in the prehabilitation group (27.3% versus 54.5%). Percentage weight loss during treatment was 3.0% in the prehabilitation group versus 4.3% in the control group. Compared with the control group, the prehabilitation group demonstrated 0.0% versus 18.2% 30-d postoperative readmission rate and 18.2% versus 27.3% 90-d postoperative readmission rate. There were no statistically significant differences between groups in regard to complications or mortality.

CONCLUSIONS

The pilot prehabilitation program demonstrated feasibility of implementing a structured program for patients receiving neoadjuvant therapy for esophageal cancer. Although the small population limits evaluation of statistical significance, trends in the data suggest a potential benefit of the prehabilitation program on neoadjuvant hospital admission rates, postsurgical readmission rates, and nutritional status.

Disparities Predict for Higher Rates of Cut-through Hysterectomies in Locally Advanced Cervical Cancer

OBJECTIVES

The treatment of choice for locally advanced cervical cancer is definitive chemoradiation (CRT). Hysterectomy is not indicated due to higher-rates of cut-through resections leaving gross disease behind, requiring additional therapy with increasing morbidity and no benefit in overall survival (OS). The objectives of this study were to determine factors associated with cut-through hysterectomies and evaluate OS outcomes.

MATERIALS AND METHODS

The National Cancer Database (NCDB) was queried for patients 18 years and older with clinical Federation of Gynecology and Obstetrics stage IB2 to IVA. All patients underwent upfront hysterectomy and had known margin status. Cut-through hysterectomy was classified as presence of microscopic or macroscopic disease at the margin.

RESULTS

A total of 11,638 patients were included; 993 (8.5%) had positive margins. In patients with positive margins, 560 (56.4%) received postoperative CRT and 148 (14.9%) underwent postoperative radiation. Five-year OS was worse for those with cut-through resections when compared with those with negative margins, 66.0% versus 86.7%, respectively (hazard ratios, 3.08; P<0.001). Under multiple logistic regression, African American race (odds ratio [OR], 1.45; P=0.001), older age (OR per year increase, 1.03; P<0.001), patients with government insurance (OR, 1.21; P=0.019), and those treated at community practices (OR, 1.31; P=0.001) were more likely to undergo cut-through hysterectomies.

CONCLUSIONS

A review of national patterns of care over the past decade confirms women with positive margins after hysterectomy for cervical cancer have significantly worse OS. Disparities in surgical results for women with cervical cancer exist. In response, further causality evaluation and corrective action are warranted to address these inequalities.

Early outcomes in patients with locally advanced rectal cancer following total neoadjuvant therapy

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Background: The current standard treatment for locally advanced rectal cancer (LARC) is neoadjuvant chemoradiation followed by surgery, and then adjuvant chemotherapy. An alternative approach currently being offered to patients at University of Colorado is total neoadjuvant therapy (TNT), in which patients receive all of their planned treatment, including systemic chemotherapy, preoperatively. Methods: Records of patients from the University of Colorado multidisciplinary colorectal clinic between 2/2015 and 5/2017 were retrospectively reviewed. Treatment plans for included patients involved 8 cycles of preoperative chemotherapy with FOLFOX (5-fluoruracil, oxaliplatin, leucovorin), followed by chemoradiation with concurrent capecitabine, and then resection. Patient data collected includes demographic information, initial staging, chemotherapy and radiation received, adverse effects, surgical outcomes, and clinical and pathological response to treatment. Results: At the time of our analysis, 14 patients have completed TNT and undergone surgical resection, with either abdominoperineal resection or low anterior resection (LAR), at the University of Colorado. Patients ranged in age from 39 to 74 years (mean age 56) with 8 patients (57%) female sex. All 14 patients received 5-fluorouracil with all 8 cycles, though 4 (29%) required omission of oxaliplatin by cycle 8. Toxicities from preoperative treatment were as expected, without significant delays in surgery. Of the 14 patients, 4 (29%) showed a pathologic complete response (grade 0, no residual tumor) on their surgical pathology, with 8 (57%) having either grade 0 or 1 (minimal residual tumor) response. Of the 5 patients who underwent LAR with diverting loop ileostomies, mean time to ostomy reversal was 53.6 days (range 49-61). No patients developed clinically-apparent metastatic disease during preoperative therapy. Conclusions: The use of preoperative chemotherapy in addition to standard chemoradiation for locally advanced rectal cancer is well-tolerated, results in a high rate of pathologic complete response, and allows for early reversal of diverting ileostomies.

Adjuvant radiotherapy improves overall survival in patients with resected gastric adenocarcinoma: A National Cancer Data Base analysis

BACKGROUND

For patients with resectable gastric adenocarcinoma, perioperative chemotherapy and adjuvant chemoradiotherapy (CRT) are considered standard options. In the current study, the authors used the National Cancer Data Base to compare overall survival (OS) between these regimens.

METHODS

Patients who underwent gastrectomy for nonmetastatic gastric adenocarcinoma from 2004 through 2012 were divided into those treated with perioperative chemotherapy without RT versus those treated with adjuvant CRT. Survival was estimated and compared using univariate and multivariate models adjusted for patient and tumor characteristics, surgical margin status, and the number of lymph nodes examined. Subset analyses were performed for factors chosen a priori, and potential interactions between treatment and covariates were assessed.

RESULTS

A total of 3656 eligible patients were identified, 52% of whom underwent perioperative chemotherapy and 48% of whom received postoperative CRT. The median follow-up was 47 months, and the median age of the patients was 62 years. Analysis of the entire cohort demonstrated improved OS with adjuvant RT on both univariate (median of 51 months vs 42 months; P = .013) and multivariate (hazard ratio, 0.874; 95% confidence interval, 0.790-0.967 [P = .009]) analyses. Propensity score-matched analysis also demonstrated improved OS with adjuvant RT (median of 49 months vs 39 months; P = .033). On subset analysis, a significant interaction was observed between the survival impact of adjuvant RT and surgical margins, with a greater benefit of RT noted among patients with surgical margin-positive disease (hazard ratio with RT: 0.650 vs 0.952; P for interaction <.001).

CONCLUSIONS

In this National Cancer Data Base analysis, the use of adjuvant RT in addition to chemotherapy was associated with a significant OS advantage for patients with resected gastric cancer. The survival advantage observed with adjuvant CRT was most pronounced among patients with positive surgical margins. Cancer 2017;123:3402-9. © 2017 American Cancer Society.

Predictors of Radiation Therapy-Related Gastrointestinal Toxicity From Anal Cancer Dose-Painted Intensity Modulated Radiation Therapy: Secondary Analysis of NRG Oncology RTOG 0529

PURPOSE

NRG Oncology RTOG 0529 assessed the feasibility of dose-painted intensity modulated radiation therapy (DP-IMRT) to reduce the acute morbidity of chemoradiation with 5-fluorouracil (5FU) and mitomycin-C (MMC) for T2-4N0-3M0 anal cancer. This secondary analysis was performed to identify patient and treatment factors associated with acute and late gastrointestinal (GI) adverse events (AEs).

METHODS AND MATERIALS

NRG Oncology RTOG 0529 treatment plans were reviewed to extract dose-volume data for tightly contoured small bowel, loosely contoured anterior pelvic contents (APC), and uninvolved colon outside the target volume (UC). Univariate logistic regression was performed to evaluate association between volumes of each structure receiving doses ≥5 to 60 Gy (V5-V60) in 5-Gy increments between patients with and without grade ≥2 acute and late GI AEs, and grade ≥3 acute GI AEs. Additional patient and treatment factors were evaluated in multivariate logistic regression (acute AEs) or Cox proportional hazards models (late AEs).

RESULTS

Among 52 evaluable patients, grade ≥2 acute, grade ≥2 late, and grade ≥3 acute GI AEs were observed in 35, 17, and 10 patients, respectively. Trends (P<.05) toward statistically significant associations were observed between grade ≥2 acute GI AEs and small bowel dose (V20-V40), grade ≥2 late GI AEs and APC dose (V60), grade ≥3 acute GI AEs and APC dose (V5-V25), increasing age, tumor size >4 cm, and worse Zubrod performance status. Small bowel volumes of 186.0 cc, 155.0 cc, 41.0 cc, and 30.4 cc receiving doses greater than 25, 30, 35, and 40 Gy, respectively, correlated with increased risk of acute grade ≥2 GI AEs.

CONCLUSIONS

Acute and late GI AEs from 5FU/MMC chemoradiation using DP-IMRT correlate with radiation dose to the small bowel and APC. Such associations will be incorporated in the dose-volume normal tissue constraint design for future NRG oncology anal cancer studies.

Impact of facility volume on outcomes in patients with squamous cell carcinoma of the anal canal: Analysis of the National Cancer Data Base

BACKGROUND

Given the rarity of anal cancer and the technical aspects involved in radiation (RT) planning, the authors conducted a population-based analysis evaluating the impact of radiation oncology facility volume on overall survival (OS) in patients with squamous cell carcinoma (SCC) of the anal canal.

METHODS

The National Cancer Data Base (NCDB) was queried for patients with SCC of the anal canal who underwent RT. All patients were coded as having received their entire course of RT at the NCDB reporting facility. Facility volume was categorized into tertiles (low, intermediate, and high) and was based on the number of times a facility's unique identification code appeared.

RESULTS

In total, 13,550 patients were identified. Patients who received treatment at higher volume radiation oncology facilities had longer OS based on multivariate analysis (MVA) (hazard ratio, 0.81; 95% confidence interval [CI], 0.73-0.90; P < .001) and propensity score matching analysis (hazard ratio, 0.79; 95% CI, 0.69-0.91; P < .001). For patients who received treatment at low-volume, intermediate-volume, and high-volume centers, the 5-year OS rate was 70%, 72.2%, and 75.4%, respectively (P < .001). Compared with low/intermediate-volume radiation oncology centers, high-volume centers were more likely to treat patients with concurrent chemotherapy (odds ratio, 1.27; 95% CI, 1.07-1.51; P = .006) and less likely to have treatment delays leading to an RT duration of >45 days (odds ratio, 0.74; 95% CI, 0.69-0.80; P < .001).

CONCLUSIONS

Treatment at higher volume radiation oncology centers appears to be associated with improved OS in patients with SCC of the anal canal. These results likely reflect the relation between physician experience and delivery of high-quality RT, which perhaps is best evident in rare tumors such as anal SCC. Cancer 2017;123:228-236. © 2016 American Cancer Society.

The Multidisciplinary Approach to GI Cancer Results in Change of Diagnosis and Management of Patients. Multidisciplinary Care Impacts Diagnosis and Management of Patients

BACKGROUND

The multidisciplinary approach to GI cancer is becoming more widespread as a result of multimodality therapy. At the University of Colorado Hospital (UCH), we utilize a formal multidisciplinary approach through specialized clinics across a variety of settings, including pancreas and biliary cancer, esophageal and gastric cancer, liver cancer and neuroendocrine tumors (NET), and colorectal cancer. Patients with these suspected diagnoses are seen in a multidisciplinary clinic. We evaluated whether implementation of disease-specific multidisciplinary programs resulted in a change in diagnosis and/or change in management for these patients.

METHODS

Data from 1747 patients were prospectively collected from inception of each multidisciplinary program through December 31, 2015. Change in diagnosis was defined as a change in radiographic or endoscopic findings that resulted in a change in cancer stage or clinical diagnosis and/or a change in pathologic diagnosis. Reports of incidental findings unrelated to primary diagnosis on radiographic evaluation were also assessed, but not included in overall change in diagnosis findings. We further evaluated if patients had a change in the management of their disease compared with outside recommendations.

RESULTS

Of 1747 patients evaluated, change occurred in 38 % (pancreas and biliary), 13 % (esophageal and gastric); 22 % (liver and NET), and 16 % (colorectal). Change in management for each multidisciplinary program occurred in 35 % (pancreas and biliary), 20 % (esophageal and gastric), 27 % (liver and NET), and 13 % (colorectal).

CONCLUSIONS

The use of a multidisciplinary clinic to manage GI cancer has a substantial impact in change in diagnosis and/or management in more than one-third of patients evaluated.

Multidisciplinary management for esophageal and gastric cancer

The management of esophageal and gastric cancer is complex and involves multiple specialists in an effort to optimize patient outcomes. Utilizing a multidisciplinary team approach starting from the initial staging evaluation ensures that all members are in agreement with the plan of care. Treatment selection for esophageal and gastric cancer often involves a combination of chemotherapy, radiation, surgery, and palliative interventions (endoscopic and surgical), and direct communication between specialists in these fields is needed to ensure appropriate clinical decision making. At the University of Colorado, the Esophageal and Gastric Multidisciplinary Clinic was created to bring together all experts involved in treating these diseases at a weekly conference in order to provide patients with coordinated, individualized, and patient-centered care. This review details the essential elements and benefits of building a multidisciplinary program focused on treating esophageal and gastric cancer patients.

Multidisciplinary management of pancreatic adenocarcinoma with isolated pulmonary metastases

384

Background: Metastatic pancreatic adenocarcinoma (PAC) with isolated pulmonary metastases has recently been associated with prolonged overall survival. The purpose of this study was to review multi-disciplinary management and outcomes of these patients. Methods: Patients with PAC with pulmonary-only metastases were queried between 2012 to 2015 from a prospective single-institutional database. Results: Ten patients (median age: 71 yrs) were identified. Median number of lung metastases at diagnosis was 3 (range: 1 to innumerable). Seven patients had biopsy-proven lung metastases. Five presented with synchronous metastatic disease and five developed metachronous lung metastases as their first site of progression. Median time to progression between diagnosis of primary cancer to diagnosis of pulmonary metastases was 15 months (range: 4 to 31). Seven patients are alive as of this analysis. Median overall survival (OS) of this series (including two patients diagnosed 3 and 6 months ago) is 17 months, with longest overall survival = 40+ months (patient is still alive). All patients received gemcitabine-based chemotherapy; however, systemic regimens differed and included investigational agents. 3 of 5 patients with metachronous metastases underwent pancreaticoduodenectomy and are long-term survivors (34-40+ months). 2 of these 3 patients had diagnostic VATS of lung metastases and are alive with overall survival of 36+ months (resection of 2/3 nodules) and 34+ months (resection of all visible disease). Two patients with metachronous disease underwent neoadjuvant chemotherapy and pancreatic SBRT with progression to lung prior to planned surgery (OS: 30 months (deceased) and 6+ months (recently diagnosed)). 0 of 5 patients with synchronous metastatic disease had surgical resection; 3 of 5 received pancreatic SBRT. 3 of 10 patients are deceased due to visceral disease (14 months), pulmonary failure (18 months), and unknown causes (30 months). Conclusions: We report a recent single-institutional series of PAC with isolated lung metastases. Our data support that metastatic PAC patients with isolated pulmonary metastases have prolonged overall survival and suggest that local intervention may be beneficial.

Stereotactic body radiation therapy for pancreatic cancer: Assessing motion with and without abdominal compression

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Background: Stereotactic body radiation therapy (SBRT) is an emerging treatment option for locally advanced pancreatic cancer. This ablative therapy requires highly accurate delivery due to nearby organs at risk. To minimize tumor motion, our institution applies abdominal compression during computed tomography (CT) simulation. The purpose of this study is to evaluate the effect of compression in the context of pancreatic SBRT. Methods: In the last 6 months, 32 patients who completed SBRT to the pancreas at our institution were selected for analysis. In each patient, two 4DCT images were acquired, one with and one without abdominal compression. Abdominal compression was achieved with an indexed compression belt with a customized degree of inflation. Each patient had fiducial markers implanted in or near the pancreatic tumor prior to simulation. These fiducials were contoured on both planning CT scans for each gated phase. Motion was assessed by fiducial position changes throughout each gated phase. Results: In the anterior to posterior, transverse, and superior to inferior dimension, compression decreased motion in 19 of 32 cases (59%), 21 of 32 cases (66%), and 28 of 32 cases (88%) respectively. In the anterior to posterior (AP) dimension compression decreased motion by a mean of 0.43mm ± 1.7mm with a range of -2.1-6.5mm (p = 0.16). The mean decrease in motion with compression in the transverse dimension was 0.93mm ± 1.9mm with a range of -1.6-8.6mm (p = 0.01). In the superior to inferior dimension, compression decreased motion by a mean of 2.72mm ± 2.8mm with a range of -1.2-11.5mm (p < 0.001). Displacement of tissue due to compression led to increased patient AP separation at the level of T12 by a mean of 9.1±5.8mm (p < 0.001). Conclusions: Abdominal compression significantly reduced tumor motion in the superior to inferior and transverse directions for patients undergoing SBRT to the pancreas. This decrease in motion allows for significant reductions in the size of the volume necessary to treat the tumor. Given our findings, we would recommend using abdominal compression over free-breathing for pancreatic SBRT.

Establishing a framework for building multidisciplinary programs

While most providers support the concept of a multidisciplinary approach to patient care, challenges exist to the implementation of successful multidisciplinary clinical programs. As patients become more knowledgeable about their disease through research on the Internet, they seek hospital programs that offer multidisciplinary care. At the University of Colorado Hospital, we utilize a formal multidisciplinary approach across a variety of clinical settings, which has been beneficial to patients, providers, and the hospital. We present a reproducible framework to be used as a guide to develop a successful multidisciplinary program.

Profile of bevacizumab and its potential in the treatment of cervical cancer

Blocking angiogenesis is an effective antitumor strategy proven in many disease sites. Anti-angiogenic therapies are fulfilling the promise of improved outcomes in cervical cancer as demonstrated in several recent trials. With its overall survival improvement in metastatic or recurrent cervical cancer, a frame shift in the management of these patients has occurred. The US Food and Drug Administration approval of bevacizumab in advanced cervical cancer has led to national guidelines, including the US National Comprehensive Cancer Network guidelines for cervical cancer, including systemic regimens containing bevacizumab as first line combination therapy. Future trials will build on this anti-angiogenesis backbone via targeting additional novel pathways and potentially leading to further improved outcomes in cervical cancer.

Clinical potential of bevacizumab in the treatment of metastatic and locally advanced cervical cancer: current evidence

The addition of bevacizumab to established therapies for metastatic and locally advanced cervical cancer is an area of evolving research and a potential strategy toward improving historically suboptimal outcomes for women with advanced disease. Bevacizumab, when added to first-line chemotherapy, has now been shown to improve overall survival among women with metastatic cervical cancer, and recent Phase II data suggests it is safe and effective for patients with locally advanced disease treated with curative intent. Here we review the rationale and current evidence for bevacizumab in clinical practice, with an emphasis on the emerging role of bevacizumab in the treatment of metastatic and locally advanced cervical cancer.

Rationale for ablation of oligometastatic disease and the role of stereotactic body radiation therapy for hepatic metastases

Management paradigms for metastatic solid tumors are evolving. Once regarded as uniformly incurable, today there is recognition of an intermediate oligometastatic state, where ablation of metastatic foci may improve disease control and prolong survival. In the setting of limited colorectal liver metastases, hepatic resection has resulted in favorable long-term outcomes, but is technically unsuitable for most patients. Stereotactic body radiation therapy represents an effective, noninvasive means of tumor ablation, supported by a large body of prospective evidence specific to hepatic metastases. This review examines the current rationale for ablation of oligometastatic disease, including various objectives beyond indefinite disease-free survival. The role of stereotactic body radiation therapy for ablation of hepatic metastases is then comprehensively reviewed.

High-dose MVCT image guidance for stereotactic body radiation therapy

PURPOSE

Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance.

METHODS

Two nonstandard, high-dose imaging modes were created on a tomotherapy machine by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison.

RESULTS

MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp∕mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable.

CONCLUSIONS

High-dose imaging modes are made possible on a clinical tomotherapy machine by increasing the LINAC pulse rate. Increasing the imaging dose results in increased CNRs; making it easier to distinguish the boundaries of low contrast objects. The imaging dose levels observed in this work are considered acceptable at our institution for SBRT treatments delivered in 3-5 fractions.

A phase II study of neoadjuvant therapy with cisplatin, docetaxel, panitumumab plus radiation therapy followed by surgery in patients with locally advanced adenocarcinoma of the distal esophagus (ACOSOG Z4051)

4062

Background: Multiple clinical trials have incorporated preoperative chemotherapy and radiation (RT) in an attempt to improve local tumor control, distant disease failure and overall survival rates for locally advanced but resectable adenocarcinoma of the distal esophagus and gastroesophageal junction (GEJ). This multicenter, cooperative group study combined active chemotherapy agents cisplatin (C), docetaxel (D) and the targeted EGFR agent panitumumab (P) in the induction phase followed by concurrent chemotherapy (CDP) and radiation. Pathologic complete response (pCR), a surrogate for improved survival, was the primary endpoint. Methods: From 01/15/09 to 07/22/11, 70 patients (pts) with Siewert I or II adenocarcinomas and clinical stages T3N0M0, T2-3N1M0 or T2-3N0-1M1a (celiac LN ≤ 2 cm) were accrued. Patients received cisplatin (40 mg/m2), docetaxel (40 mg/m2) and panitumumab (6 mg/kg) on weeks 1, 3, 5, 7, 9 with RT (5040 cGy, 180 cGy/day x 28d) beginning week 5. The decision rule had a 90% power with a 0.10 significance level to detect a pCR rate of at least 35%. Secondary objectives included near-pathologic complete response (near-pCR), toxicity, and overall and disease-free survival rates. Results: Five pts were ineligible. Of the remaining 65 pts (59 M, 6 F; median age 61), 12 pts did not undergo surgery (5 progressed, 4 refused, 3 other). Of the 58 evaluable pts, the pCR rate was 32.8% (90% CI: 22.6% -42.9%) and near-pCR 22.4% (90% CI: 13.4%-31.4%). Total doses of C, D, and P were achieved in 76%, 80%, and 73%, respectively (n = 70). 66 pts (94%) received the total RT dose. Sixteen pts (23%) had a grade 4+ non-heme adverse event possibly related to treatment. Venous thrombosis (5 pts) was most common. Conclusions: The CDP regimen in the neoadjuvant setting in patients with esophageal adenocarcinomas is active (pCR + near-pCR = 55.2%) and feasible. The toxicity though tolerable is substantial.

Fluorodeoxyglucose positron emission tomography response and normal tissue regeneration after stereotactic body radiotherapy to liver metastases

PURPOSE

To characterize changes in standardized uptake value (SUV) in positron emission tomography (PET) scans and determine the pace of normal tissue regeneration after stereotactic body radiation therapy (SBRT) for solid tumor liver metastases.

METHODS AND MATERIALS

We reviewed records of patients with liver metastases treated with SBRT to ≥40 Gy in 3-5 fractions. Evaluable patients had pretreatment PET and ≥1 post-treatment PET. Each PET/CT scan was fused to the planning computed tomography (CT) scan. The maximum SUV (SUV(max)) for each lesion and the total liver volume were measured on each PET/CT scan. Maximum SUV levels before and after SBRT were recorded.

RESULTS

Twenty-seven patients with 35 treated liver lesions were studied. The median follow-up was 15.7 months (range, 1.5-38.4 mo), with 5 PET scans per patient (range, 2-14). Exponential decay curve fitting (r=0.97) showed that SUV(max) declined to a plateau of 3.1 for controlled lesions at 5 months after SBRT. The estimated SUV(max) decay half-time was 2.0 months. The SUV(max) in controlled lesions fluctuated up to 4.2 during follow-up and later declined; this level is close to 2 standard deviations above the mean normal liver SUV(max) (4.01). A failure cutoff of SUV(max) ≥6 is twice the calculated plateau SUV(max) of controlled lesions. Parenchymal liver volume decreased by 20% at 3-6 months and regenerated to a new baseline level approximately 10% below the pretreatment level at 12 months.

CONCLUSIONS

Maximum SUV decreases over the first months after SBRT to plateau at 3.1, similar to the median SUV(max) of normal livers. Transient moderate increases in SUV(max) may be observed after SBRT. We propose a cutoff SUV(max) ≥6, twice the baseline normal liver SUV(max), to score local failure by PET criteria. Post-SBRT values between 4 and 6 would be suspicious for local tumor persistence or recurrence. The volume of normal liver reached nadir 3-6 months after SBRT and regenerated within the next 6 months.

A phase II study of bevacizumab in combination with definitive radiotherapy and cisplatin chemotherapy in untreated patients with locally advanced cervical carcinoma: preliminary results of RTOG 0417

PURPOSE

Concurrent cisplatin-based chemoradiotherapy (CRT) is the standard treatment for locally advanced cervical cancer. RTOG 0417 was a Phase II study exploring the safety and efficacy of the addition of bevacizumab to standard CRT.

METHODS AND MATERIALS

Eligible patients with bulky tumors (Stage IB-IIIB) were treated with once-weekly cisplatin (40 mg/m(2)) chemotherapy and standard pelvic radiotherapy and brachytherapy. Bevacizumab was administered at 10 mg/kg intravenously every 2 weeks for three cycles. Treatment-related serious adverse event (SAE) and other adverse event (AE) rates within the first 90 days from treatment start were determined. Treatment-related SAEs were defined as any Grade ≥ 4 vaginal bleeding or thrombotic event or Grade ≥ 3 arterial event, gastrointestinal (GI) bleeding, or bowel/bladder perforation, or any Grade 5 treatment-related death. Treatment-related AEs included all SAEs and Grade 3 or 4 GI toxicity persisting for >2 weeks despite medical intervention, Grade 4 neutropenia or leukopenia persisting for >7 days, febrile neutropenia, Grade 3 or 4 other hematologic toxicity, and Grade 3 or 4 GI, renal, cardiac, pulmonary, hepatic, or neurologic AEs. All AEs were scored using the National Cancer Institute Common Terminology Criteria (CTCAE) v 3.0 (MedDRA version 6.0).

RESULTS

A total of 60 patients from 28 institutions were enrolled between 2006 and 2009, and of these, 49 patients were evaluable. The median follow-up was 12.4 months (range, 4.6-31.4 months).The median age was 45 years (range, 22-80 years). Most patients had FIGO Stage IIB (63%) and were of Zubrod performance status of 0 (67%). 80% of cases were squamous. There were no treatment-related SAEs. There were 15 (31%) protocol-specified treatment-related AEs within 90 days of treatment start; the most common were hematologic (12/15; 80%). 18 (37%) occurred during treatment or follow-up at any time. 37 of the 49 patients (76%) had cisplatin and bevacizumab administered per protocol, and 46 of the 49 (94%) had both external beam and brachytherapy administered per protocol or with acceptable variation.

CONCLUSION

Bevacizumab in addition to standard pelvic chemoradiotherapy for locally advanced cervical cancer is feasible and safe with respect to the protocol-specified treatment-related SAEs and AEs.

Radiation therapy for liver metastases

Liver metastases are a common source of cancer morbidity and mortality and are often the only site of metastases. In the last 2 decades, major technological advancements in radiation treatment planning and delivery have resulted in resurgence in the use of radiation therapy (RT) as a treatment for liver tumors. With the advent of 3-dimensional conformal radiation treatment (CRT), partial liver irradiation became possible. Stereotactic body radiation therapy (SBRT) is a further enhancement, defined as highly focused, stereotactically localized and administered, high-dose RT delivered in a hypofractionated course. There is now more than a decade of experience with CRT and SBRT for the treatment of liver metastases. In selected patients, very high local control rates have been observed, with minimal toxicity. Patients most likely to benefit from RT are those with liver confined disease, focal distribution of metastases, and metastases more than 1.5 cm from luminal gastrointestinal organs. There is growing evidence that strategies using aggressive or ablative local therapies as an adjunct to systemic therapy might achieve improvements in overall outcome as long as they are administered safely.

Stereotactic body radiotherapy for colorectal liver metastases: a pooled analysis

BACKGROUND

This study was undertaken to determine outcomes of stereotactic body radiotherapy for colorectal liver metastases in a pooled patient cohort.

METHODS

Patients with colorectal liver metastases from 3 institutions were included if they had 1 to 4 lesions, received 1 to 6 fractions of stereotactic body radiotherapy, and had radiologic imaging ≥ 3 months post-treatment. Sixty-five patients with 102 lesions treated from August 2003 to May 2009 were retrospectively analyzed. A tumor control probability (TCP) model was used to estimate the 3-fraction dose required for > 90% local control after converting the schedule into biologically equivalent dose (BED), single-fraction equivalent dose, or linear quadratic model-based single-fraction dose.

RESULTS

Forty-seven (72%) patients had ≥ 1 chemotherapy regimen before stereotactic body radiotherapy, and 27 (42%) patients had ≥ 2 regimens. The median follow-up was 1.2 years (range, 0.3-5.2 years). The median dose was 42 gray (Gy; range, 22-60 Gy). When evaluated separately by multivariate analysis, total dose (P = .0015), dose/fraction (P = .003), and BED (P = .004) all correlated with local control by lesion. On multivariate analysis, nonactive extrahepatic disease was associated with overall survival (OS; P = .046), and sustained local control was closely correlated (P = .06). By using single-fraction equivalent dose, BED, or linear quadratic model-based single-fraction dose in the TCP model, the estimated dose range needed for 1-year local control > 90% is 46 to 52 Gy in 3 fractions.

CONCLUSIONS

Liver stereotactic body radiotherapy is well tolerated and effective for colorectal liver metastases. The strong correlation between local control and OS supports controlling hepatic disease even for heavily pretreated patients. For a 3-fraction regimen of stereotactic body radiotherapy, a prescription dose of ≥ 48 Gy should be considered, if normal tissue constraints allow.

Esophageal cancer patients undergoing external beam radiation after placement of self-expandable metal stents: is there a risk of radiation dose enhancement?

BACKGROUND

Self-expandable metal stents (SEMSs) are used for palliation of malignant dysphagia. It is not known whether dose adjustments are required when there is a stent in the radiation field.

OBJECTIVE

To measure the effects of esophageal stents of various designs and materials on radiation dose to the tissue adjacent to the stent in the radiation field to determine whether there should be any dose adjustment.

DESIGN

Simulated clinical protocol.

SETTING

Linear accelerator radiation treatment center.

PATIENTS

Solid Water phantoms were used to mimic the tissue environment of the human esophagus as well as stents of various designs and materials and controls.

INTERVENTIONS

Radiation beams composed of photons (x-rays) delivered in split dosing with energies of 6, 10, and 15 million volts.

MAIN OUTCOME MEASUREMENTS

Film and image-based evidence of dose enhancement; Monte Carlo calculations.

RESULTS

Dose enhancement from single beams was seen only on the anterior surface, particularly in the stainless steel Z-stent (3.5%-7.8%) and the nonmetal Polyflex stent (5.5%-8.8%); less dose enhancement was seen on the anterior surface of the Alimaxx and Ultraflex nitinol stents (2%-2.5%). A negligible dose effect was seen on the posterior wall of all the stents tested. Monte Carlo calculation results were roughly similar to actual dosimeter measurements.

LIMITATIONS

Simulated clinical protocol.

CONCLUSIONS

This tissue-mimicking model reveals that radiation dose enhancement is a function of stent design and material, and the dose reduction is unnecessary as long as multiple fields are used.

Stereotactic body radiation therapy for melanoma and renal cell carcinoma: impact of single fraction equivalent dose on local control

BACKGROUND

Melanoma and renal cell carcinoma (RCC) are traditionally considered less radioresponsive than other histologies. Whereas stereotactic body radiation therapy (SBRT) involves radiation dose intensification via escalation, we hypothesize SBRT might result in similar high local control rates as previously published on metastases of varying histologies.

METHODS

The records of patients with metastatic melanoma (n = 17 patients, 28 lesions) or RCC (n = 13 patients, 25 lesions) treated with SBRT were reviewed. Local control (LC) was defined pathologically by negative biopsy or radiographically by lack of tumor enlargement on CT or stable/declining standardized uptake value (SUV) on PET scan. The SBRT dose regimen was converted to the single fraction equivalent dose (SFED) to characterize the dose-control relationship using a logistic tumor control probability (TCP) model. Additionally, the kinetics of decline in maximum SUV (SUVmax) were analyzed.

RESULTS

The SBRT regimen was 40-50 Gy/5 fractions (n = 23) or 42-60 Gy/3 fractions (n = 30) delivered to lung (n = 39), liver (n = 11) and bone (n = 3) metastases. Median follow-up for patients alive at the time of analysis was 28.0 months (range, 4-68). The actuarial LC was 88% at 18 months. On univariate analysis, higher dose per fraction (p < 0.01) and higher SFED (p = 0.06) were correlated with better LC, as was the biologic effective dose (BED, p < 0.05). The actuarial rate of LC at 24 months was 100% for SFED ≥45 Gy v 54% for SFED <45 Gy. TCP modeling indicated that to achieve ≥90% 2 yr LC in a 3 fraction regimen, a prescription dose of at least 48 Gy is required. In 9 patients followed with PET scans, the mean pre-SBRT SUVmax was 7.9 and declined with an estimated half-life of 3.8 months to a post-treatment plateau of approximately 3.

CONCLUSIONS

An aggressive SBRT regimen with SFED ≥ 45 Gy is effective for controlling metastatic melanoma and RCC. The SFED metric appeared to be as robust as the BED in characterizing dose-response, though additional studies are needed. The LC rates achieved are comparable to those obtained with SBRT for other histologies, suggesting a dominant mechanism of in vivo tumor ablation that overrides intrinsic differences in cellular radiosensitivity between histologic subtypes.

Chest wall volume receiving >30 Gy predicts risk of severe pain and/or rib fracture after lung stereotactic body radiotherapy

PURPOSE

To identify the dose-volume parameters that predict the risk of chest wall (CW) pain and/or rib fracture after lung stereotactic body radiotherapy.

METHODS AND MATERIALS

From a combined, larger multi-institution experience, 60 consecutive patients treated with three to five fractions of stereotactic body radiotherapy for primary or metastatic peripheral lung lesions were reviewed. CW pain was assessed using the Common Toxicity Criteria for pain. Peripheral lung lesions were defined as those located within 2.5 cm of the CW. A minimal point dose of 20 Gy to the CW was required. The CW volume receiving >or=20, >or=30, >or=40, >or=50, and >or=60 Gy was determined and related to the risk of CW toxicity.

RESULTS

Of the 60 patients, 17 experienced Grade 3 CW pain and five rib fractures. The median interval to the onset of severe pain and/or fracture was 7.1 months. The risk of CW toxicity was fitted to the median effective concentration dose-response model. The CW volume receiving 30 Gy best predicted the risk of severe CW pain and/or rib fracture (R(2) = 0.9552). A volume threshold of 30 cm(3) was observed before severe pain and/or rib fracture was reported. A 30% risk of developing severe CW toxicity correlated with a CW volume of 35 cm(3) receiving 30 Gy.

CONCLUSION

The development of CW toxicity is clinically relevant, and the CW should be considered an organ at risk in treatment planning. The CW volume receiving 30 Gy in three to five fractions should be limited to <30 cm(3), if possible, to reduce the risk of toxicity without compromising tumor coverage.

Multi-institutional phase I/II trial of stereotactic body radiation therapy for liver metastases

PURPOSE

To evaluate the efficacy and tolerability of high-dose stereotactic body radiation therapy (SBRT) for the treatment of patients with one to three hepatic metastases.

PATIENTS AND METHODS

Patients with one to three hepatic lesions and maximum individual tumor diameters less than 6 cm were enrolled and treated on a multi-institutional, phase I/II clinical trial in which they received SBRT delivered in three fractions. During phase I, the total dose was safely escalated from 36 Gy to 60 Gy. The phase II dose was 60 Gy. The primary end point was local control. Lesions with at least 6 months of radiographic follow-up were considered assessable for local control. Secondary end points were toxicity and survival.

RESULTS

Forty-seven patients with 63 lesions were treated with SBRT. Among them, 69% had received at least one prior systemic therapy regimen for metastatic disease (range, 0 to 5 regimens), and 45% had extrahepatic disease at study entry. Only one patient experienced grade 3 or higher toxicity (2%). Forty-nine discrete lesions were assessable for local control. Median follow-up for assessable lesions was 16 months (range, 6 to 54 months). The median maximal tumor diameter was 2.7 cm (range, 0.4 to 5.8 cm). Local progression occurred in only three lesions at a median of 7.5 months (range, 7 to 13 months) after SBRT. Actuarial in-field local control rates at one and two years after SBRT were 95% and 92%, respectively. Among lesions with maximal diameter of 3 cm or less, 2-year local control was 100%. Median survival was 20.5 months.

CONCLUSION

This multi-institutional, phase I/II trial demonstrates that high-dose liver SBRT is safe and effective for the treatment of patients with one to three hepatic metastases.