Trifluridine/tipiracil: A practical guide to its use in the management of refractory metastatic colorectal cancer in Australia

Trifluridine/Tipiracil (FTD/TPI) in Metastatic Colorectal Cancer in Hong Kong: A Territory-Wide Cohort Study

INTRODUCTION

Randomized phase III trials showed that using trifluridine/tipiracil (FTD/TPI) in patients with pre-treated metastatic colorectal cancer (mCRC) conferred survival benefit versus placebo. Here, we investigated the effectiveness and safety of FTD/TPI and sought to identify prognostic factors among the mCRC population in Hong Kong.

METHODS

A non-interventional, retrospective, multicenter cohort study enrolled patients with mCRC who received FTD/TPI in seven public hospitals in Hong Kong between 2016 and 2020. Overall survival (OS) was the primary endpoint; treatment duration and occurrence of neutropenia were secondary endpoints. We also performed a post hoc analysis to identify factors influencing OS and treatment duration.

RESULTS

Overall, 456 patients were included (median age, 64.0 years; 57.5% men). Approximately half (225/456; 49.3%) had RAS wild-type tumors; the median treatment duration was 12.4 weeks (95% confidence interval [CI] 11.1-13.1). Median OS was 7.59 months (95% CI 7.00-8.21). Overall, 289 (63.4%) patients developed neutropenia of any grade and 159 (34.9%) developed grade ≥ 3 neutropenia. Neutropenia at 1 month occurred in 193 (43.1%) patients. The use of granulocyte colony-stimulating factor for neutropenia was reported for 42 (9.2%) patients. The development of neutropenia, absolute neutrophil count decrease of ≥ 2 grades in 1 month, absence of liver metastasis, and RAS wild-type status were associated with significantly longer OS and, except for RAS wild-type status (not analyzed), longer treatment duration (p < 0.05 for all comparisons).

CONCLUSION

Our data show that treatment with FTD/TPI offers survival benefits in patients with refractory mCRC in Hong Kong consistent with randomized controlled trials and other real-world studies. Furthermore, the prognosis in patients receiving FTD/TPI appears to be significantly better in those who develop neutropenia, with RAS wild-type status, or those without liver metastases, despite a higher rate of dose reduction in the real-world setting.

Pan-Cancer Molecular Patterns and Biological Implications Associated with a Tumor-Specific Molecular Signature

Studying tissue-independent components of cancer and defining pan-cancer subtypes could be addressed using tissue-specific molecular signatures if classification errors are controlled. Since PAM50 is a well-known, United States Food and Drug Administration (FDA)-approved and commercially available breast cancer signature, we applied it with uncertainty assessment to classify tumor samples from over 33 cancer types, discarded unassigned samples, and studied the emerging tumor-agnostic molecular patterns. The percentage of unassigned samples ranged between 55.5% and 86.9% in non-breast tissues, and gene set analysis suggested that the remaining samples could be grouped into two classes (named C1 and C2) regardless of the tissue. The C2 class was more dedifferentiated, more proliferative, with higher centrosome amplification, and potentially more TP53 and RB1 mutations. We identified 28 gene sets and 95 genes mainly associated with cell-cycle progression, cell-cycle checkpoints, and DNA damage that were consistently exacerbated in the C2 class. In some cancer types, the C1/C2 classification was associated with survival and drug sensitivity, and modulated the prognostic meaning of the immune infiltrate. Our results suggest that PAM50 could be repurposed for a pan-cancer context when paired with uncertainty assessment, resulting in two classes with molecular, biological, and clinical implications.