Metabolic syndrome and colorectal cancer: is hyperinsulinemia/insulin receptor-mediated angiogenesis a critical process?

OBJECTIVE: Components of metabolic syndrome (MS) have been individually linked to colorectal cancer risk and prognosis; however, an understanding of the dominant mechanisms is lacking. MATERIALS AND METHODS: Twenty-one patients (10 MS; 11 non-MS) with resectable colorectal cancer were prospectively enrolled. Patients were classified for MS by the World Health Organization criteria and tested for circulating vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), insulin-like growth factor-1 (IGF-1), fasting insulin, and tumor expression of IGF-1 receptor (IGF-1R), insulin-receptor (IR) and receptor for advanced glycation end-products (RAGE). Circulating markers were re-tested 6 months after surgery. RESULTS: The MS group had significantly higher baseline and post-operative fasting insulin levels (p < 0.001 and 0.003). No differences were observed in circulating IL-6, VEGF, IGF-1 and free IGF-1. By immunohistochemistry (IHC), IGF-1R expression was significantly higher in tumor vs. normal tissues (p < 0.001) while IR expression showed no difference. Interestingly, 64% of tumors demonstrated high IR positivity in the vessels within or surrounding the tumor stroma, but not in the vessels away from the tumor. By reverse transcription polymerase chain reaction (RT-PCR), tumor IGF-1R over-expression (80%) was confirmed, but there was no difference between MS and non-MS patients. Tumor RAGE over-expression was found in 67% of patients and was equally distributed between the two groups. CONCLUSIONS: Hyperinsulinemia was the only significant factor distinguishing patients with colorectal cancer who have MS. The preferential over-expression of IR in the peri-tumoral microvessels suggests that hyperinsulinemia might contribute to colorectal cancer growth by enhancing angiogenesis.

Predicting the risk of chemotherapy toxicity in older patients: the Chemotherapy Risk Assessment Scale for High-Age Patients (CRASH) score.

BACKGROUND: Tools are lacking to assess the individual risk of severe toxicity from chemotherapy. Such tools would be especially useful for older patients, who vary considerably in terms of health status and functional reserve. METHODS: The authors conducted a prospective, multicentric study of patients aged ≥70 years who were starting chemotherapy. Grade 4 hematologic (H) or grade 3/4 nonhematologic (NH) toxicity according to version 3.0 of the Common Terminology Criteria for Adverse Events was defined as severe. Twenty-four parameters were assessed. Toxicity of the regimen (Chemotox) was adjusted using an index to estimate the average per-patient risk of chemotherapy toxicity (the MAX2 index). In total, 562 patients were accrued, and 518 patients were evaluable and were split randomly (2:1 ratio) into a derivation cohort and a validation cohort. RESULTS: Severe toxicity was observed in 64% of patients. The Chemotherapy Risk Assessment Scale for High-Age Patients (CRASH) score was constructed along 2 subscores: H toxicity and NH toxicity. Predictors of H toxicity were lymphocytes, aspartate aminotransferase level, Instrumental Activities of Daily Living score, lactate dehydrogenase level, diastolic blood pressure, and Chemotox. The best model included the 4 latter predictors (risk categories: low, 7%; medium-low, 23%; medium-high, 54%; and high, 100%, respectively; P(trend) < .001). Predictors of NH toxicity were hemoglobin, creatinine clearance, albumin, self-rated health, Eastern Cooperative Oncology Group performance, Mini-Mental Status score, Mini-Nutritional Assessment score, and Chemotox. The 4 latter predictors provided the best model (risk categories: 33%, 46%, 67%, and 93%, respectively; P(trend) < .001). The combined risk categories were 50%, 58%, 77%, and 79%, respectively; P(trend) < .001). Bootstrap internal validation and independent sample validation demonstrated stable risk categorization and P(trend) < .001. CONCLUSIONS: The CRASH score distinguished several risk levels of severe toxicity. The split score discriminated better than the combined score. To the authors' knowledge, this is the first score systematically integrating both chemotherapy and patient risk for older patients and has a potential for future clinical application.

Can first cycle CBCs predict older patients at very low risk of neutropenia during further chemotherapy?

Elderly cancer patients with normal complete blood cell counts (CBCs) during the first course of (some types of) chemotherapy might be unlikely to experience grade 4 neutropenia during subsequent cycles. In this case, further weekly CBCs might be avoided. We used data of 223 cancer patients aged 70+ who were included in the CRASH (Chemotherapy Risk Assessment Score for High-age patients) trial between 2003 and 2007 in 7 cancer practices in the US. First cycle CBC values were compared to subsequent cycles. MAX2-score was used as a measure for toxicity of the chemotherapy regimen. Sixty-two patients (28%) experienced grade 4 neutropenia during subsequent cycles. Among patients who received chemotherapy with a MAX2-score lower than 0.20, only 4.6% of those without neutropenia during the first cycle experienced grade 4 neutropenia during subsequent cycles. Weekly CBC might be avoided in these patients receiving chemotherapy. Future prospective studies should confirm these results.