Goodman Capecitabine vs 5-FU IMRT

Background

Retrospective bi-institutional cohort, N=107, non-metastatic anal SCC treated with definitive IMRT-based chemoradiation 2009–2014. Compares fluoropyrimidine partner after 2011 practice shift from infusional 5-FU to capecitabine; aim was acute toxicity reduction.

Interventions and follow up

Arm A (n=44): IMRT (median 56 Gy) + capecitabine 825 mg/m² BID (Mon–Fri) + MMC 10 mg/m² (wk 1, 5)
Arm B (n=63): IMRT (median 56 Gy) + 5-FU 1000 mg/m²/d ×4d (wk 1, 5) + MMC 10 mg/m² (wk 1, 5)
Primary endpoint: Acute toxicity (hematologic); treatment breaks
mFollow up: Multi-year retrospective comparison

Results

Grade 3–4 neutropenia: 52% (5-FU) vs 20% (capecitabine), P=.001
Treatment breaks due to toxicity: 42% (5-FU) vs 16% (capecitabine), P=.006
Baseline characteristics: Comparable (median age 59 yr, 73% female)

Adverse events

Grade 3–4 neutropenia: 52% (5-FU) vs 20% (capecitabine), P=.001
Treatment breaks: 42% (5-FU) vs 16% (capecitabine), P=.006
Dermatologic/GI toxicity: No significant difference

Conclusions

Substituting oral capecitabine for infusional 5-FU with MMC and IMRT significantly reduces grade 3–4 neutropenia (52% → 20%) and treatment delays (42% → 16%), supporting capecitabine as a preferred fluoropyrimidine for anal cancer chemoradiation.

Key Limitations

Retrospective, non-randomized sequential-era comparison subject to selection and temporal bias; small sample; efficacy/disease control not the primary endpoint; single fluoropyrimidine/MMC regimen.

Clinical Context

Supports capecitabine/MMC as a tolerable, convenient alternative to infusional 5-FU/MMC for definitive anal cancer chemoradiation, consistent with widely adopted practice in major treatment guidelines.

References