[Colorectal cancer in patients younger than 40 years of age]

Colorectal cancer in young adults: a retrospective study of 32 tunisian patients

Young people under the age of 40 with colorectal cancer represent a distinct subgroup with a more aggressive disease behaviour compared to older patients. This study aim to provide an updated overview on clinicopathological features, treatment and outcome of colorectal cancer in young adults under the age of 40. In our retrospective study, we reviewed 32 cases of colorectal cancer in young adults aged less than 40 years that were diagnosed at the pathology department of Mongi Slim hospital over a fifteen-year period (April 2000 - November 2014). Our study group included 13 male and 19 female patients (sex-ratio M/F = 0,68) between 17 and 39 years of age (mean = 31,25 years). The presenting clinical symptoms were dominated by altered bowel habits (n=17), followed by bleeding per rectum (n=16). Histopathological examination of the surgical and biopsy specimens established the diagnosis of mucinous adenocarcinoma in nine cases, well-differentiated adenocarcinoma in 11 cases, moderately differentiated adenocarcinoma in six cases, poorly differentiated adenocarcinoma in four cases and signet ring cell carcinoma in two cases. The tumours were classified after surgery as stage I (n = 2) (6%), stage IIA (n = 7) (22%), stage IIB (n=4) (13%), stage IIC (n=1) (3%), stage IIIB (n=8) (25%), stage IIIC (n= 4) (12%), stage IVA (n=4) (13%) and stage IVB (n=2) (6%). During the follow-up period which ranged between one month and 9 years, local recurrence of the tumour occurred in six cases, seven patients had hepatic metastases and seven patients died after a mean follow-up period of seven months. Molecular genetic studies are increasing the understanding of the pathobiology of colorectal cancer and may ultimately allow at-risk patients to be identified at an earlier stage.

Racial differences in the anatomical distribution of colorectal cancer: a study of differences between American and Chinese patients

AIM: To compare the racial differences of anatomical distribution of colorectal cancer (CRC) and determine the association of age, gender and time with anatomical distribution between patients from America (white) and China (oriental).

METHODS: Data was collected from 690 consecutive patients in Cleveland Clinic Florida, U.S.A. and 870 consecutive patients in Nan Fang Hospital affiliated to the First Military Medical University, China over the past 11 years from 1990 to 2000. All patients had colorectal adenocarcinoma diagnosed by histology and underwent surgery.

RESULTS: The anatomical subsite distribution of tumor, age and gender were significantly different between white and oriental patients. Lesions in the proximal colon (P < 0.001) were found in 36.3% of white vs 26.0% of oriental patients and cancers located in the distal colon and rectum in 63.7% of white and 74% of oriental patients (P < 0.001). There was a trend towards the redistribution from distal colon and rectum to proximal colon in white males over time, especially in older patients (> 80 years). No significant change of anatomical distribution occurred in white women and Oriental patients. The mean age at diagnosis was 69.0 years in white patients and 48.3 years in Oriental patients (P < 0.001).

CONCLUSION: This is the first study comparing the anatomical distribution of colorectal cancers in whites and Chinese patients. White Americans have a higher risk of proximal CRC and this risk increased with time. The proportion of white males with CRC also increased with time. Chinese patients were more likely to have distal CRC and developed the disease at a significantly earlier age than white patients. These findings have enhanced our understanding of the disease process of colorectal cancer in these two races.