P-257 - Intensity of adjuvant chemotherapy regimens among elderly stage III colon cancer patients

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Anti-Cancer Agents & Biologic Therapy
Geriatric Oncology
Colon Cancer
Presenter F. van Erning
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors F. van Erning1, M. Janssen-Heijnen1, Y. van de Wouw1, G.-. Creemers2, V. Lemmens1
  • 1Netherlands Comprehensive Cancer Organisation, Eindhoven/NL
  • 2Catharina Hospital, Eindhoven/NL

Abstract

Introduction

Little is known about the intensity of adjuvant chemotherapy (adjCT) among elderly stage III colon cancer patients treated in clinical practice.

Methods

Stage III colon cancer patients aged ≥70 years diagnosed in southern-Netherlands between 2005-2012 who received adjCT were included (n = 406). Logistic regression assessed variables influencing receipt of capecitabine with oxaliplatin (CAPOX) vs. capecitabine monotherapy (CapMono). Variables included were gender, age, comorbidity, ASA score, pT-pN stage, tumor subsite, differentiation grade, period and hospital of diagnosis. Differences in completion of all planned cycles, delays, and dosage reductions were calculated using &KHgr;2-tests. Based on standard total dosages (STD) within CAPOX of 1,040 mg/m2 for oxaliplatin and 224,000 mg/m2 for capecitabine, patients were categorized as receiving >75%, 50-75% or <50% of the STD. For CapMono, STD was 280,000 mg/m2.

Results

Most patients received CAPOX (n = 193, 48%) or CapMono (n = 164, 40%). Patients aged ≥80years vs. 70-80years (14% vs. 58%, OR 0.06, 95%CI 0.02-0.21), diagnosis in 2005-2006 vs. 2011-2012 (40% vs. 55%, OR 0.33 95%CI 0.14-0.77), ASA score III-IV vs. I-II (43% vs. 58%, OR 0.42, 95%CI 0.20-0.90), and from some hospitals (range 33-78%) were less likely to receive CAPOX. Completion differed between CAPOX and CapMono (33% vs. 55%, p < 0.0001). In CAPOX, 39 patients did not complete oxaliplatin, 8 patients capecitabine and 81 patients both. Non-completion appeared not related to listed patient and tumor characteristics. Toxicity was the reason for non-completion in 84% for CAPOX and in 65% for CapMono (p = 0.003). Other specified reasons which did not differ between regimens were patient/family choice (10-16%); local/distant recurrence (4-6%); and death (3-4%).

The proportion in which a delay in ≥1 cycle due to medical reasons (laboratory values, toxicity) was observed differed between CAPOX and CapMono (32% vs. 22%, p = 0.032).

For CAPOX, 42% received >75% of STD for capecitabine, 24% received 50-75% of STD and 27% received <50% of STD. In 7% total dosage was unknown. For oxaliplatin, these proportions were 21%, 32%, 40% and 7% respectively. For CapMono, proportions of patients receiving >75%, 50-75% and <50% of STD were 32%, 30% and 25% respectively. In 13% total dosage was unknown.

Among patients completing treatment, the percentage in whom dosage reduction before or during cycles was applied differed between CAPOX (63%) and CapMono (43%) (p = 0.014). Most important reason for dosage reduction was toxicity (83% vs. 87%, p = 0.562).

Conclusion

Large variation exists in total dosages for CAPOX and CapMono. Only one-third of elderly receiving CAPOX completed all cycles, and dosage reductions were still applied in over half of these patients. Among elderly receiving CapMono, completion was higher but still relatively low and dosage reductions were applied in almost half of these patients.