There is a well-documented association between neoplastic polyps and colorectal cancer (CRC) in the adenoma-carcinoma sequence (1,2). Therefore, the majority of authorities recommend screening to identify and remove neoplastic polyps prior to their transformation into invasive CRC (3-7). However, the majority of Caribbean countries still do not have policies in place for universal CRC screening. This is largely due to the lack of prioritization by policy makers, resource limitations in the underfunded healthcare systems and a paucity of regional data to support CRC screening (8).

The present study thus aimed to document the epidemiology of neoplastic colorectal polyps and to obtain important data that may be used to guide screening protocols in Jamaica. To the best of our knowledge, there has been no prior report on the distribution or prevalence of neoplastic colorectal polyps in the Jamaican population.

There were 480 colonoscopies performed over the study period using an Olympus 160 series colonoscope (Olympus Corporation). A standardized bowel preparation technique was used that included clear fluids for 12 h, three sachets of PicoPrep^® (sodium picosulphate) at 6-h intervals and two Dulcolax (Bisacodyl) tablets 6 h prior to the colonoscopy.

These screening colonoscopies were all performed by expert gastroenterologists who were trained in accredited post-graduate fellowship programs. The caecum was intubated in 456 (95%) cases and no complications were recorded in these cases.

These patients were deemed average-risk undergoing screening. There was a family history of colorectal carcinoma in a first degree relative in 11 (2.3%) patients, a history of inflammatory bowel disease in 2 (0.4%) patients and none with a past personal history of malignancies, lynch syndrome or familial adenomatous polyposis coli (0%).

Of the total of 480 colonoscopies, 395 patients without polyps and 15 patients with non-neoplastic polyps were excluded from further analysis, leaving a total of 70 patients with neoplastic polyps in the study population. The clinicopathological features of the patients included in the study are presented in Table I. These patients were of Afro-Caribbean (n=67), Caucasian (n=2) and Chinese (n=1) ethnicity. There were 37 males and 33 females with a mean age of 65.9 years (range, 29-88; median, 65; SD, ±11.65). A representation of the patient demographics by age is presented in Fig. 1.

In total, 45 patients had a solitary polyp and synchronous polyps were present in 25 patients: 22 patients had 2 polyps, 1 patient had 3 polyps and there were two females in the study with multiple polyps throughout the colon as a part of a polyposis syndrome. The number of polyps in the 2 patients with polyposis syndrome could not be counted accurately; thus, they were excluded from further analysis. This left a total number of 92 neoplastic polyps in 68 patients as the final study population.

The distribution of neoplastic polyps throughout the colon in these patients is illustrated in Fig. 2. The most common location was the right side (55.6%), followed by left-sided lesions (38%) and then the rectum (6.5%). Upon the histological evaluation, 63 polyps were found to be benign adenomas with mild to moderate dysplastic alterations and 23 of these had a villous morphology. These polyps had a mean size of 1.02±0.85 cm. There were 15 adenomas with high-grade dysplasia, 10 of which had a villous morphology. These 15 adenomas had a mean size of 1.8±1.28 cm. In total, 14 polyps had foci of invasive carcinomas and all 14 had a villous morphology. These polyps were larger in size with a mean diameter of 2.57±0.61 cm. The distribution of neoplastic polyps according to their histological evaluation is presented in Table II.

The majority of authorities recommend CRC screening to detect neoplastic polyps when there is still an opportunity for polypectomy prior to their progression into invasive cancer (3-7). However, there was still only opportunistic screening in Jamaica up to the year 2021, despite an estimated incidence of CRC of 12 per 100,000 individuals in the population (8).

Previous studies have documented a ‘right shift’ in the Jamaican population (8-10) and in other Caribbean territories (11-13), where CRC primaries have become more prevalent in the right colon. Therefore, it was predictable that the precursor neoplastic polyps were most prevalent in the right colon in the present study. This is a change in disease distribution compared to studies from the 20th century, where CRC was predominantly left-sided (14,15). In that era, some experts advocated sigmoidoscopy for screening. However, it is clear that a colonoscopy is required in modern screening programs, since neoplastic polyps and CRC are more common in the right colon.

The ‘right side’ shift cannot be overemphasized as there are fundamental differences in the clinical behavior of lesions, depending on the geographical origin in the colon (16). Right-sided CRCs have a high association with microsatellite instability and tend to present late, with non-specific symptoms (13), a higher cancer-related mortality rate (18-20) and worse overall survival statistics (17,20).

It was not surprising that the present study found a male predominance for neoplastic polyps (1.1:1) as previous studies have reported a predominance for invasive CRC among males (11,13,21). The demographic distribution was also predictable with a peak in the 6th to 8th decades of life. This matches the age distribution for invasive CRC in the Caribbean literature (8-13). However, it is notable that 7% of patients with neoplastic polyps were <49 years of age. In the possibility that the traditional recommendations for screening had commenced at the age of 50 years (4) had been followed, these polyps would have been missed (two of which had already undergone malignant alterations), as these polyps had evidently been formed at an earlier age. This was slightly lower than similar data reported from Barbados, where 10.3% of CRC diagnoses were made in individuals <49 years of age (13). These data lend support to the updated recommendations for CRC screening to begin at the age of 45 years in the Caribbean population (5). These are important data as there is an established association between a young age at diagnosis and aggressive disease, a higher CRC stage (22) and lower survival rates (17,22). Although it is only a small proportion of the overall study group, it is still an important public health message that 7% of Jamaicans with precursor neoplastic polyps will be <49 years of age.

It should be noted that 96% of the patients in the present study were of Afro-Caribbean ethnicity. This was expected, since the matriline of the Jamaican population is almost entirely of West African descent (23). It is well-established that when individuals from the African diaspora develop CRC, they have a more aggressive tumor biology (17,22,24,25), a greater association with KRAS mutations (17,26) and an increased cancer-related mortality (22,24). There is still an ongoing debate on whether these differences are due to a lack of screening, oncology care access inequities, socioeconomic factors or genuine differences in tumor biology; however, the fact that this is a predominantly Afro-Caribbean population must be recognized.

The present study documented the epidemiology of neoplastic colorectal polyps and demonstrated that these precursor lesions for CRC were identified in 15% of individuals who underwent colonoscopies. It is considered that these results will lend support to the call for policy makers to implement national screening protocols (3,5). In the year 2018, the Caribbean Association of Hematology Oncology facilitated a consensus meeting of Caribbean experts to create guidelines for CRC tailored to the Caribbean environment. These guidelines were endorsed by the National Comprehensive Cancer Network (NCCN) in the NCCN Harmonized Guidelines for the Caribbean (5). Thus, perhaps the time has come for Jamaican policy makers to implement these protocols.

In conclusion, the present study demonstrated that ~15% of individuals who underwent colonoscopies had neoplastic polyps that were as recognized precursor lesions for CRC. There is also a predominance in right-sided polyps, with 56% of neoplastic colorectal polyps being found in the right colon. These results support the call for policy makers to institute national CRC screening programs, such as the NCCN harmonized guidelines for the Caribbean.