Neoplasia detected in a third of patients under 50 after colorectal screening

19th January 2022

Neoplasia (precancerous lesions) have been detected in a third of patients aged 45 to 49 years of age after colorectal screening

The presence of neoplasia or precancerous lesions, have been identified after colorectal screening in patients aged 45 to 49 years of age, highlighting the need for lowering the age of such screening for average risk individuals. This was the finding from an examination of real-world outpatient colonoscopy data by a team from the Dr. Henry D. Janowitz Division of Gastroenterology, New York, US.

Colorectal cancer is a malignant tumour that forms in the tissues of the colon and is often grouped together with rectal cancer, due to the fact that these cancers share common features. During 2020 in Europe, colorectal cancer became the second most common cancer and the second highest cause of cancer death, accounting for 12.7% of all new cancer diagnoses and 12.4% of cancer deaths.

Moreover, the importance of screening has been highlighted in a study which observed that the largest decreases in colorectal cancer mortality were seen in countries with long-standing screening programmes.

The incidence of early-onset colorectal cancer (i.e., cases in those aged under 50 years of age) has seen a world-wide increase, especially in high-income countries although the reasons behind this increase are uncertain.

In addition, data suggests that the incidence of deaths due to early-onset colorectal cancer are also rising, had that these had increased by 1.3% annually between 2008 and 2017, in those aged younger than 50 years. Despite this, most screening programmes in Europe begin at 50 years of age.

But could there be an advantage from earlier screening and could this help identify those with neoplasia? This was the aim of the present study and the US team analysed data from a large and nationally representative set of outpatient colonoscopies to identify colorectal neoplasia among patients aged 18 to 54 years of age.

They undertook a retrospective analysis of colonoscopy data and compared a ‘young onset group (defined as aged 18 to 49) with those aged 50 to 54 years.

Findings

A total of 562,559 colonoscopy procedures were included in the analysis, 145,998 of which were undertaken in those aged 18 to 44 years and 79,934 in those aged 45 to49 years.

Among individuals aged 45 to 49, approximately 32% had any form of neoplasia, 7.5% had advanced premalignant lesions and 0.58% had colorectal cancer with a neoplasia present in 26.6% of those aged 40 to 44 years.

Discussing their findings, the authors stated that in a representative sample of patients under 50 years of age, the prevalence of any neoplasia among those aged 45 to 49 were almost as high as in those in the 50 to 54 year olds. They concluded that lowering the screening age to 45 will likely enable the detection of important pathology more frequently.

Citation

Trivedi PD et al. Prevalence and Predictors of Young-Onset Colorectal Neoplasia: Insights from a Nationally Representative Colonoscopy Registry Gastroenterology 2022.

Risk of early-onset colorectal cancer reduced by higher intake of vitamin D

3rd August 2021

A large prospective study has revealed that a higher intake of vitamin D in women is linked to a lower risk of early-onset colorectal cancer.

Colorectal cancer is the third most common cancer worldwide, accounting for an estimated 1.8 million new cases and over 880,000 deaths in 2018. However, the incidence of early-onset colorectal cancer (EOCRC), defined as colorectal cancer in those under 50 years of age, is increasing by approximately 7.9% per year among those aged 20 – 29 years. Moreover, EOCRC is more often diagnosed at an advanced stage. While the reasons for this are uncertain, it could be linked to sedentary behaviour or obesity. A further compounding factor, is the delay in seeking advice with one study in 1089 patients with EOCRC, reporting that nearly two-thirds of patients waited 3 – 12 months before seeking medical advice, with many indicating that they were initially misdiagnosed.

One potential protective factor against colorectal cancer is vitamin D and there is evidence of a strong inverse relationship between vitamin D levels and the risk of colorectal cancer. Nevertheless, whether reduced plasma levels of vitamin D are also associated with the development of early-onset colorectal cancer is uncertain. In trying to ascertain the relationship between these two factors, a team from the Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, US, turned to the Nurses’ Health Study II which is a prospective cohort study of 116,429 female nurses aged between 25 and 42 years and which began in 1989. Study participants are followed every 2 years by self-administered questionnaires which captures information on demographics, lifestyle factors, the presence of co-morbidities etc and a food frequency questionnaire, every 4 years. For the present study, the researchers set the primary end point as the development of EOCRC, identified from medical records. In addition, the researchers collected data on the presence of adenomas and serrated polyps, which are pre-cancerous lesions. The plasma vitamin D levels were estimated based on factors such as dietary intake, age, race etc using a previously defined model.

Findings
A total of 94,205 women were included in the analysis and there were 111 documented cases of early-onset colorectal cancer detected between 1991 and 2015. The median vitamin D intake was 372 IU/day and vitamin D levels > 450 IU/day were associated with a reduced risk of developing EOCRC compared to intakes < 300 IU/day (hazard ratio, HR = 0.49, 95% CI 0.26–0.93). The HR per 400 IU/day increases was 0.46 (95% CI 0.26–0.83). Interestingly, the researchers also found that the HR for dietary vitamin D intake had a stronger inverse association with the development of EOCRC per 400 IU/day increase than among supplement users (0.34 vs 0.77, dietary vs supplements). There were 1439 newly diagnosed adenomas and 1878 serrated polyps in those aged less than 50 years and again, higher vitamin D intake was associated with a lower risk of developing either lesion.

The authors concluded that given the association between higher vitamin D intake and early-onset colorectal cancer, strategies to ensure adequate intake of the vitamin could serve as an important preventative measure in younger adults.

Citation
Kim H et al. Total Vitamin D Intake and Risks of Early-Onset Colorectal Cancer and Precursors. Gastroenterology. 2021