Pooled data suggests obese patients with CRC may benefit from weight-based chemotherapy doses
Therefore, the researchers suggested in a presentation at the 2021 European Society for Medical Oncology (ESMO) World Congress on Gastrointestinal Cancer (ESMO) that ACRD is greater than the mean relative dose intensity (ARDI ) to determine patient survival.
âAdjuvant chemotherapy is dosed based on a person’s body surface area, which is calculated from their height and weight. But in obese patients (with a high body mass index [BMI], and who are more likely to have high BSA [body surface areas]), doses are often capped or based on ideal body weight for fear that large doses may increase side effects. This means that obese patients can receive proportionately lower doses of chemotherapy, âsaid lead author of the study, Corinna Slawinski, clinical research fellow in the Division of Cancer Sciences at the University of Manchester, at the University of Manchester. United Kingdom, before the presentation.
Previous reports have shown that obese patients with CRC have poorer results, but this study suggests that these earlier results may be limited or due to other factors, including treatment.
Recently, the American Society of Clinical Oncology (ASCO) updated its guidelines for the treatment of obese cancer patients to recommend full doses of chemotherapy based on weight. The consortium’s findings support these guidelines.
âOur study demonstrated an association between increased body mass index and modest cumulative relative dose reductions of adjuvant chemotherapy in patients with colorectal cancer. And we also found an association between an increased cumulative relative dose and improved survival, âSlawinski said.
The OCTOPUS consortium included patient-level data including 7,269 eligible patients from several large randomized studies of the use of adjuvant chemotherapy for CRC (MOSAIC, NCT00275210; SCOT, ISRCTN59757862; PROCTOR-SCRIPT, ISRCTN36266738; and CHRONICLE, NCT00427713). Investigators analyzed BMI and BSA related to chemotherapy doses in patients receiving treatment after undergoing curative surgery.
The primary endpoint was disease-free survival (DFS), with secondary measures of overall survival (OS) and cancer-specific survival (CSS).
BMI increments of 5 kg / m2 were associated with a 2.04% lower chemotherapy dose in Cycle 1 (95% CI, -2.45 to -1.64; P P = .009) and ARDI (-1.02%; 95% CI, -1.43% to -0.62%; P <.001 thus a patient with bmi of kg m2 would have reduction in acrd and ardi compared to m>2.
Five percent increases in ACRD were associated with improvement in SSM (RR: 0.953; 95% CI: 0.926-0.980; P = 0.001), OS (RR, 0.931; 95% CI, 0.908-0.955; P P <.001>
Elizabeth Smyth, MD, consultant in gastrointestinal oncology at Addenbrooke’s Hospital in Cambridge, UK, and member of the ESMO faculty for gastrointestinal tumors, commented on the results of the study: âThe reductions in dose for a high BMI may be associated with lower cure rates. in resected colon cancer treated with adjuvant chemotherapy. Adjuvant chemotherapy has the potential to cure patients with residual micrometastatic disease after curative surgery, so it is important to maximize the benefit for all patients.
âThe main message of this study is that we need to determine whether dose reductions are needed in patients with high BMI when receiving adjuvant chemotherapy,â Smyth added. âThe dosage of chemotherapy is complex and includes not only weight, but also physical form, comorbidities including kidney function and results of dihydropyrimidine dehydrogenase tests. “
The study authors noted that further prospective studies are needed before treatment practices can be changed.
âWe have to take all aspects of the patient into account when making decisions about chemotherapy dosing. Dose reductions appear to be associated with [worse] survival in this study, but these may still be necessary for safety, âurged Smyth.
1. Slawinski C, Malcomson L, Barriuso J, et al. The mean cumulative relative dose (ARD) of adjuvant chemotherapy is more important than the mean relative dose intensity (ARDI) for colorectal cancer survival, with implications for the treatment of obese patients: the OCTOPUS consortium. Ann Oncol. 2021; 32 (suppl 3): O-4.
2. Griggs JJ, Bohlke K, Balaban EP, et al. Appropriate dosage of systemic therapy for obese adult cancer patients: update of the ASCO guideline. J Clin Oncol. 2021; 39 (18): 2037-2048. doi: 10.1200 / JCO.21.00471