Pre-treatment lymphopenia as a prognostic biomarker in colorectal cancer patients receiving chemotherapy.

BACKGROUND: Lymphopenia is a predictor of the efficacy and hematological toxicity of chemotherapy in various advanced cancers. There is little data about this relationship in colorectal cancer. In this retrospective study, the influence of pretreatment lymphopenia on hematological toxicity and the efficacy of chemotherapy was investigated in colorectal cancer patients. PATIENTS AND METHODS: In total, 260 patients were included in the study. Correlations between pre-treatment lymphopenia (lymphocyte count < 1,000/µl) and the occurrence of hematological toxicity and efficacy of first-line palliative chemotherapy were investigated. RESULTS: Lymphopenia was found in 49/260 (19%) patients. Ten of these patients with lymphopenia (20.4%) experienced severe hematological toxicity compared with 17 of the remaining 211 (8%) patients (P = 0.01). Lymphopenia was identified as an independent factor for hematological toxicity. Among patients who received palliative chemotherapy, the objective response rate was significantly lower in lymphopenic patients than in the other patients (12.5% vs. 40.2%; P = 0.004). Lymphopenia was strongly associated with shorter progression-free survival (median 4 vs. 7 months; P = 0.033) and shorter overall survival (median 16 vs. 24 months, P = 0.024). Multivariate analysis revealed that lymphopenia had an independent effect on survival. CONCLUSIONS: Our findings show that lymphopenia is an independent predictive factor for both hematological toxicity and efficacy of chemotherapy in colorectal cancer. Pre-treatment lymphocyte count may represent a simple and new predictive biomarker of chemotherapy effects in colorectal cancer patients.

Circulating free tumor DNA and colorectal cancer.

Cancer is characterized by multiple somatic genetic and epigenetic alterations that could be useful as molecular markers for detecting tumor DNA in different bodily fluids. In patients with various diseases as well as in healthy subjects, circulating plasma and serum carry small amounts of non-cell-bound DNA. In this free circulating DNA, tumor-associated molecular alterations can be detected in patients who have cancer. In many instances, the alterations identified are the same as those found in the primary tumor tissue, thereby suggesting tumor origin from a fraction of the circulating free DNA. In fact, various types of DNA alterations described in colorectal cancer have been detected in the circulating free DNA of patients with colorectal cancer. These alterations include KRAS2, APC and TP53 mutations, DNA hypermethylation, microsatellite instability (MSI) and loss of heterozygosity (LOH). Also, advances in polymerase chain reaction (PCR)-based technology now allow the detection and quantification of extremely small amounts of tumor-derived circulating free DNA in colorectal cancer patients. The present report summarizes the literature available so far on the mechanisms of circulating free DNA, and on the studies aimed at assessing the clinical and biological significance of tumor-derived circulating free DNA in colorectal cancer patients. Thus, tumor-derived circulating free DNA could serve as a marker for the diagnosis, prognosis and early detection of recurrence, thereby significantly improving the monitoring of colorectal cancer patients.

[Long-term evolution of achalasia of the lower esophageal sphincter and intestinal paraneoplasic pseudo-obstruction revealing small cell lung carcinoma]. / Evolution à long terme d'une achalasie du sphincter inférieur de l'esophage et d'une pseudo-obstruction intestinale paranéoplasiques révélatrices d'un carcinome pulmonaire à petites cellules.

We report a case of a small cell carcinoma of the lung revealed by chronic intestinal pseudo-obstruction associated with achalasia of the lower esophageal sphincter. Tumoral remission was achieved for more than 21 months after chemoradiotherapy but this did not prevent the paraneoplasic syndrome from persisting and medical treatment was not successful in treating the intestinal pseudo-obstruction or the dysphagia, which was not improved by esophageal dilation.