New Research on Rectal Cancer Treatment Shows Promising Results

Strategic Insights -

Researchers at the University of California, Irvine have made a significant breakthrough in rectal cancer treatment. According to a phase II trial, short-course radiation therapy (SC RT) followed by three months of trifluridine/tipiracil (FTD/TPI) plus oxaliplatin (TASOX) chemotherapy has shown promising results in treating intermediate-risk rectal cancer. The study aimed to determine the efficacy of this condensed total neoadjuvant therapy (TNT) regimen in reducing the neoadjuvant response (NAR) score in patients with clinical T3N0 or T1-3N1 nonlow rectal tumors.

Key Takeaways:

  • The phase II trial, SHORT, enrolled 13 patients with stage II and III rectal adenocarcinoma between 2020 and 2023.
  • The study found that 100% of patients received 100% of planned radiation, 99% of planned FTD/TPI, and 95% of planned oxaliplatin doses.
  • Diarrhea was reported in 11% of patients, and all cases were grade 1. Only 9% of adverse events were grade 3/4.
  • Ten patients proceeded to total mesorectal excision surgery, with two experiencing a pathological complete response and two having a complete clinical response.
  • The study concluded that SC RT and 3 months of TASOX can be safely delivered to patients with intermediate-risk rectal cancer, offering a convenient regimen that should be further explored for rectal cancer treatment.
  • The TASOX regimen may be particularly relevant for patients with suspected dihydropyrimidine dehydrogenase deficiency who require oxaliplatin-based therapy.

Statistics:

  • 100% of patients received 100% of planned radiation doses.
  • 99% of patients received 99% of planned FTD/TPI doses.
  • 95% of patients received 95% of planned oxaliplatin doses.
  • 11% of patients experienced diarrhea.
  • 9% of adverse events were grade 3/4, predominantly related to neutropenia.
  • 10 patients proceeded to total mesorectal excision surgery.
  • 2 patients experienced a pathological complete response.
  • 2 patients had a complete clinical response.
  • 1 patient had no evidence of regrowth on continued watch and wait.

Sources:

  • University of California Irvine Researchers Discuss Findings in Rectal Cancer [Results of a phase II trial of short-course radiation and TASOX [trifluridine/tipiracil (TAS-102) plus oxaliplatin] chemotherapy in operable rectal cancer]. Cancer Weekly. September 9, 2025; p 1344.
  • Results of a phase II trial of short-course radiation and TASOX [trifluridine/tipiracil (TAS-102) plus oxaliplatin] chemotherapy in operable rectal cancer. ESMO Gastrointestinal Oncology, 2025, 9():100215.