Treatment breaks in first line treatment of advanced colorectal cancer: An individual patient data meta-analysis.

BACKGROUND: Intermittent systemic anti-cancer therapy in patients with advanced colorectal cancer (aCRC) may improve quality of life without compromising overall survival (OS). We aimed to use individual patient data meta-analysis (IPDMA) from multiple randomised controlled trials evaluating intermittent strategies to inform clinical practice. We also aimed to validate whether thrombocytosis as a predictive biomarker identified patients with significantly reduced OS receiving a complete treatment break. PATIENTS AND METHODS: An IPDMA of intermittent strategy impact on survival was undertaken, including all relevant trials in which data were available. Intermittent strategies were classified into two groups: a planned stopping of all therapy ("treatment break strategy"; 6 trials; 2,907 patients) or to the same treatment omitting oxaliplatin ("maintenance strategy"; 3 trials; 1,271 patients). The primary analysis sample was of patients successfully completing induction therapy. Additionally, a pre-planned analysis of the predictive value of thrombocytosis on survival under a continuous versus an intermittent strategy was undertaken. RESULTS: All trials had comparable inclusion criteria. The overall IPDMA of intermittent therapy versus continuous therapy demonstrated no detriment in OS (HR = 1.03 [95% CI 0.93-1.14]), whether from complete break (HR 1.04 [95% CI 0.87-1.26]) or maintenance strategies (HR 0.99 [95% CI 0.87-1.13]). Thrombocytosis was confirmed as a marker of poor prognosis in aCRC, but did not predict for OS detriment from treatment break strategies (interaction HR = 0.97 [95% CI 0.66-1.40] compared to continuous therapy). CONCLUSION: The highest levels of evidence from this IPDMA indicate no detriment in survival for patients receiving an intermittent therapy strategy, either for maintenance or complete break strategies. Although, thrombocytosis is confirmed as a marker of poor prognosis, it is not predictive of poor outcome for patients treated with intermittent therapy. An intermittent chemotherapy strategy can therefore be applied irrespective of baseline platelet count and does not result in inferior OS compared to continuous chemotherapy.

Radiation therapy induced changes in male sex hormone levels in rectal cancer patients.

BACKGROUND AND PURPOSE: To determine the effect of curative radiation therapy (46-50 Gy) on the sex hormone levels in male rectal cancer patients. MATERIALS AND METHODS: Twenty-five male rectal cancer patients (mean age 65 years), receiving pelvic radiation therapy (2 Gyx23-25 fractions in 5 weeks) were included. Serum testosterone, FSH and LH were determined before start of treatment, at the 10th and 25th fractions, and 4-6 weeks after completed radiotherapy. The testicular dose was determined by thermoluminescent dosimetry. RESULTS: Five weeks of radiation therapy (46-50 Gy) resulted in a 100% increase in serum FSH, a 70% increase in LH, and a 25% reduction in testosterone levels. After treatment, 35% of the patients had serum testosterone levels below lower limit of reference. The mean radiation dose to the testicles was 8.4 Gy. A reduction in testosterone values was observed already after a mean dose of 3.3 Gy (10th fraction). CONCLUSION: Radiation therapy (46-50 Gy) for rectal cancer resulted in a significant increase in serum FSH and LH and a significant decrease in testosterone levels, indicating that sex hormone production is sensitive to radiation exposure in patients with a mean age of 65 years.