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Is Radiation Consistently Necessary for Mid-High Rectal Cancers? Assigned Viewpoint: No Great Debates Symposium New York City, NY Deb Schrag MD Dana Farber Cancer Institute Harvard Medical School March 28th 2014 Background: Why Question Use of Neoadjuvant XRT? • Current standard of care for all Stage II-III rectal cancer is tri-modality therapy—has been so since 1990 • In 2004, German study (Sauer NEJM) demonstrated superiority of preoperative rather than post operative XRT in terms of QOL/local recurrence—drift to preop rx in USA • Neoadjuvant XRT may be overtreatment in some cases • Pelvic radiation causes short and long-term morbidity • Chemo, surgery and imaging techniques have each improved since tri-modality paradigm established • Landmark Dutch TME trial showed that XRT marginally improves LR rates, but not survival The Plural of Anecdote Doesn’t=Data, but Does Raise Provocative Questions • Patients with stage IV rectal cancer • Start with palliative chemo RT? • Start with palliative resection? • Start with systemic chemotherapy? • High response rate and conversion to resectability-omitting the preop XRT • Chemotherapy without XRT • Stage II-III RC in Prostate and GYN Cancer survivors • Women seeking fertility preservation • Men and women concerned about sexual health Challenges Arising from Neoadjuvant ChemoXRT Rectal Treatment Paradigm • Rectal patients succumb to metastatic dx • Met Rectal patients previously treated with pelvic XRT don’t tolerate sustained myelosuppressive Rx well • Node+ pts often drop out of post op adjuvant rx • Node- pts may get unnecessary rx • Met Rectal pts seem to get less chemo, end up having slightly inferior survival than colon pts • Why not spare the marrow for when its really needed? Motivating Pilot Study Experience • Single center phase II pilot at MSKCC administered 6 cycles of induction FOLFOX+Bev to patients with clinical T2N1, T3N0, T3N1 rectal cancer who were candidates for LAR at presentation • XRT planned if no response or any positive margin • Of 30 participants, none required preoperative XRT • With more than 4 years median follow up: • 1 post-op death, 2 cancer deaths • No local recurrences • 4 recurrences, all with metastases to lung JCO Jan 2014 Personal Viewpoint on Stage II/III Rectal Cancer Treatment: • All patients with T4 rectal cancer require XRT • Patients with T2-T3 rectal cancer proximal to ~12 cm on proctoscope can safely be managed without preop XRT • Patients with T2-3 distal rectal cancer requiring an APR should receive preop Chemo XRT • Patients with T2-3 rectal cancer who are candidates for Low Anterior Resection (typically ~5-12cm from anal verge) should be encouraged to enroll in PROSPECT! PROSPECT N1048-CALGB81001-ACOSOGZ6052 Full protocol available on CTSU Website (www.ctsu.org) Endorsed by SWOG, ECOG, NCIC, RTOG, NSABP An NCI Cooperative Group Phase II/III Trial of Neoadjuvant FOLFOX with Selective Use of Combined Modality Chemoradiation for Locally Advanced Rectal Cancer Patients Undergoing Low Anterior Resection with Total Mesorectal Excision PROSPECT: N1048 • Objective: • To determine if selective use of neoadjuvant XRT is a safe alternative strategy to routine use of XRT for management of locally advanced rectal cancer that is amenable to sphincter sparing TME PROSPECT: Study Design • A phase II/III NCI Cooperative Group study: • Randomized phase II of 366 patients with early stopping rule if failure to complete R0 resections or if an unacceptably high rate of Local Recurrences • Phase III component built in and will include 644 additional patients if stopping criteria are not met PROSPECT: Study Schema “Standard Arm” RANDOMIZE 1:1 5FUCMT* Response 20% TME TME Chemo per primary MD Chemo per primary MD FOLFOX x 6 “Selective Arm” 5FUCMT* Response <20% TME Chemo per primary MD *5FUCMT = infusional or oral 5FU + radiation therapy PROSPECT: Study Endpoints Primary Outcomes: • Randomized Phase II Component • R0 Resection Rate • Time to local recurrence (TLR) • Phase III Component: Co-primary endpoints • Time to local recurrence (TLR) • Disease free survival (DFS) Secondary Outcomes: • Pathologic complete response rate (Pcr) • Overall survival (OS) • Quality of life (QOL) • Clinician and patient reported treatment toxicity • Molecular correlates of response to neoadjuvant therapy • Adverse Event (AE) Profiles • Rates of receiving 5FUCMT PROSPECT: Inclusion Criteria • Biopsy proven rectal adenocarcinoma at age 18+ • Distal end of tumor located 5-12 cm from anal verge • Candidate for sphincter sparing surgery according to TME experienced surgeon at presentation • Standard treatment would be combined modality neoadjuvant chemoradiation followed by curative TME • Baseline Clinical staging: T2N1, T3N0, T3N1 • Proctoscopy by primary surgeon • MRI or ERUS (MRI preferred) • CT scan of Chest/Abdomen/Pelvis PROSPECT: Exclusion Criteria • Clinical T4 tumors • Clinical N2 disease • Defined as >=4 pelvic nodes >10mm in diameter • Not a candidate for either 5FUCMT or oxaliplatin • Tumor within 3mm of mesorectal fascia on MRI or CT • Undiverted symptomatic bowel obstruction • ECOG Performance Status of 3 or 4 • Prior pelvic radiation Staging/Restaging Evaluation • Baseline staging is identical in both arms • Restaging in selective arm is more intensive • Opportunity to give XRT if poor response to FOLFOX • Evaluate if rectal tumor decreased by 20% • Re-evaluation in selective arm: • Proctoscopy • Physical exam by primary surgeon • MRI of Pelvis or ERUS (same test as at baseline) • If response of primary tumor is: • <20%, then gets 5FUXRT • 20%, then straight to OR for TME Radiation in the Intervention Arm is Used Selectively • Criteria for Delivery of XRT in Selective Arm: • Preoperative 5FUCMT is to be administered if: • • • • Evidence of clinical progression during pre-op FOLFOX Restaging reveals rectal tumor response is an estimated <20% Unable to tolerate FOLFOXx6 at or above dose level-2 Patient withdraws consent • Postoperative 5FUCMT is recommended if: • • • • TME pathology is T4 TME pathology has any positive margin (R1 or R2 resection) Surgeon’s self assessment is that TME was incomplete Surgical/Path QA report indicates incomplete TME Treatment Considerations Balancing Consistency vs. Flexibility • Radiation • IMRT is allowed • Short course radiotherapy is not allowed • Surgery • Surgeon must be willing to submit photos of the first TME specimen for credentialing • Laparascopic and robotic assisted approaches are allowed • Sensitizing Chemotherapy with Radiation • May give capecitabine or infusional 5FU • Postoperative Chemotherapy • FOLFOX is suggested, but regimen may be tailored to patient’s tolerance of preoperative treatment • Regimen is at the discretion of the primary MD PROSPECT: Statistical Design • The primary goal is to compare selective to routine use of pre-op 5FUXRT with respect to the co-primary endpoints of Disease Free Survival (DFS) and time to local recurrence (TLR) • DFS and TLR will be considered jointly to determine whether selective or routine use of 5FUXRT is preferred • The selective 5FUXRT arm will be favored if it has either • superior DFS compared to the treat-all arm • non-inferior DFS AND non-inferior TLR Conclusions • Neoadjuvant chemotherapy strategies are an investigational approach for patients with resectable rectal CA amenable to sphincter sparing TME • XRT is a mainstay of Rx for a curable cancer 5-12 cm from the anal verge: selective approach appropriate on a trial • Patients with threatened margins are inappropriate candidates for selective use of XRT • Induction FOLFOX for pts • who can’t have XRT due to prior therapy • with stage IV disease amenable to R0 resection • With suspected metastatic disease THANK YOU • Questions? Please Contact Study Team Members with any suggestions or concerns Study Component Alliance Protocol Coordinator Contact Information [email protected] PI [email protected] Statistics [email protected] [email protected] Surgical Oncology Radiation Oncology Medical Oncology Radiology Pathology Correlative Science Quality of Life PROCTCAE [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected]