Preoperative Chemoradiotherapy With Capecitabine With or Without Temozolomide in Patients With Locally Advanced Rectal Cancer: A Prospective, Randomised Phase II Study Stratified by O6-Methylguanine DNA Methyltransferase Status: KCSG-CO17-02.

AIMS: To evaluate the clinical efficacy of adding temozolomide (TMZ) to preoperative capecitabine (CAP)-based chemoradiotherapy in patients with locally advanced rectal cancer (LARC) and validate O6-methylguanine DNA methyltransferase (MGMT) methylation status as a predictive marker for TMZ combined regimens. MATERIALS AND METHODS: LARC patients with clinical stage II (cT3-4N0) or III (cTanyN+) disease were enrolled. They were stratified into unmethylated MGMT (uMGMT) and methylated MGMT (mMGMT) groups by methylation-specific polymerase chain reaction before randomisation and were then randomly assigned (1:1) to one of four treatment arms: uMGMT/CAP (arm A), uMGMT/TMZ + CAP (arm B), mMGMT/CAP (arm C) and mMGMT/TMZ + CAP (arm D). The primary end point was the pathological complete response (pCR) rate. RESULTS: Between November 2017 and July 2020, 64 patients were randomised. Slow accrual caused early study termination. After excluding four ineligible patients, 60 were included in the full analysis set. The pCR rate was 15.0% (9/60), 0%, 14.3%, 18.8% and 26.7% for the entire cohort, arms A, B, C and D, respectively (P = 0.0498 between arms A and D). The pCR rate was 9.7% in the CAP group (arms A + C), 20.7% in the TMZ + CAP group (arms B + D), 6.9% in the uMGMT group (arms A + B) and 22.6% in the mMGMT group (arms C + D). Grade 1-2 nausea or vomiting was significantly more frequent in the TMZ + CAP treatment groups (arms B + D) than in the CAP treatment groups (arms A + C, P < 0.001) with no difference in grade 3 adverse events. There were no grade 4 or 5 adverse events. CONCLUSION: The addition of TMZ to CAP-based chemoradiotherapy tended to improve pCR rates, particularly in those with mMGMT LARC. MGMT status may warrant further investigation as a predictive biomarker for chemotherapeutic agents and radiotherapy.

A New Practical Desensitization Protocol for Oxaliplatin-Induced Immediate Hypersensitivity Reactions: A Necessary and Useful Approach.

BACKGROUND AND OBJECTIVE: Desensitization protocols for patients with immediate hypersensitivity reactions (IHSRs) have proven to be effective, but they are not widely used in clinical practice because of impracticalities such as high cost, long procedure duration, and a lack of trained personnel. We aimed to determine the clinical characteristics of oxaliplatin-induced IHSRs and assess measures to protect against these reactions and to validate a new practical desensitization protocol. METHODS: We retrospectively reviewed 2640 cases of oxaliplatin IHSRs in 271 oxaliplatin users and prospectively used a newly designed desensitization protocol 32 times in 12 patients with hypersensitivity to platinum-based chemotherapy. The protocol consisted of increases in infusion rate every 15 minutes, regardless of the concentration of the chemotherapy agent in the infusion bags. RESULTS: Of the 271 patients administered oxaliplatin, 45 (16.6%) experienced IHSRs. Of 39 patients who experienced an IHSR but needed to continue oxaliplatin, 6 (15.4%) stopped treatment due to the reaction, and 33 (84.6%) continued despite the risk of further reactions. The new desensitization protocol was successfully completed in 12 patients (100%), but it was ineffective in 3 patients (all with a negative skin prick test), who experienced fever without urticaria. CONCLUSIONS: Many patients who experience oxaliplatin-induced IHSRs are required to stop first-line oxaliplatin-based chemotherapy or to continue without desensitization, with the associated risks. Our new desensitization protocol is practical and easy to use in clinical practice.