Risk of recurrence in screen-versus non screen-detected colorectal cancer patients.

BACKGROUND & AIM: Patients with screen-detected colorectal cancer (CRC) have a better stage-specific overall survival than non-screen detected CRC. Currently, it is unknown if recurrence rates differ between screen- and non-screen detected CRCs, and whether this could explain the observed difference in overall survival. Therefore, we aimed to assess the disease-free survival (DFS) rates in screen-detected and non-screen detected CRCs and if recurrence affects overall survival. METHODS: Dutch CRC (stage I-III) patients, diagnosed by screening or not in the first six months of 2015, were included from the Netherlands Cancer Registry. DFS and survival data were retrieved and analyzed by Kaplan Meier method. The association between mode of detection and recurrence and overall survivall was evaluated with a Cox-regression model. RESULTS: A total of 3725 CRC patients were included, 2073 (55.7%) non-screen-detected and 1652 (44.3%) screen-detected CRCs. Three-year DFS was significantly higher in screen-detected CRC compared to non-screen-detected CRC (87.8% versus 77.2.%, p<0.001). Stage-specific DFS rates for screen-detected vs. non-screen-detected CRC were 94.7% vs. 92.3% for stage I (p=0.45), 84.3% vs. 81.4% for stage II (p=0.17) and 77.9% vs 66.7% for stage III (p<0.001), respectively. Detection by screening was independently associated with a lower risk of recurrence (HR 0.67; CI 0.55 - 0.81, p<0.001) when adjusted for age, gender, tumor location, stage and treatment. Recurrence independently predicted overall survival (HR 15.90; CI 13.28-19.04, p<0.001). CONCLUSION: Disease-free survival was significantly better in screen-detected compared to non-screen-detected CRCs independent of age, gender, tumor location, stage and treatment, and was associated with an overall survival benefit.

Attitudes toward genetic testing, family planning and preimplantation genetic testing in families with a germline CDKN2A pathogenic variant.

Individuals with a germline CDKN2A pathogenic variant (PV) have a highly increased life time risk of melanoma and pancreatic cancer. This cross-sectional study assessed the attitudes among toward genetic testing, family planning, and preimplantation genetic testing (PGT) in confirmed CDKN2A PV carriers and individuals with a 50% risk of the PV (at-risk carriers) using of a one-time questionnaire.A total of 537 individuals were screened for eligibility, of whom 208 of 366 (57%) confirmed carriers (56% female, median age 54 years [IQR 46-63]) and 39 of 171 (23%) at-risk carriers (59% female, median age of 26 years [IQR 22-32]) participated in the study. Primary motivations for genetic testing were to gain control over their personal and children's cancer risk, as well as increasing cancer surveillance practices. In contrast, concerns about obtaining a mortgage and life insurance were frequently cited as reasons for postponing genetic testing. Family planning decisions remained largely unaffected in both confirmed and at-risk carriers; however, the majority of confirmed carriers were still unaware of their familial or personal cancer risk when starting a family. More than 60% of the participants were unfamiliar with PGT and only a minority (19% of confirmed carriers and 10% of at-risk carriers) would be open to considering PGT as a reproductive option. This study found different attitudes toward genetic testing, family planning, and PGT among individuals affected by the CDKN2A PV. Understanding these different attitudes can help clinicians to address the complexities surrounding these issues, especially for younger individuals facing difficult decisions about the timing of genetic testing, family planning, and the potential use of assisted reproductive options.

Colibactin mutational signatures in NTHL1 tumor syndrome and MUTYH associated polyposis patients.

Polyketide synthase (pks) island harboring Escherichia coli are, under the right circumstances, able to produce the genotoxin colibactin. Colibactin is a risk factor for the development of colorectal cancer and associated with mutational signatures SBS88 and ID18. This study explores colibactin-associated mutational signatures in biallelic NTHL1 and MUTYH patients. Targeted Next Generation Sequencing (NGS) was performed on colorectal adenomas and carcinomas of one biallelic NTHL and 12 biallelic MUTYH patients. Additional fecal metagenomics and genome sequencing followed by mutational signature analysis was conducted for the NTHL1 patient. Targeted NGS of the NTHL1 patient showed somatic APC variants fitting SBS88 which was confirmed using WGS. Furthermore, fecal metagenomics revealed pks genes. Also, in 1 out of 11 MUTYH patient a somatic variant was detected fitting SBS88. This report shows that colibactin may influence development of colorectal neoplasms in predisposed patients.

Colorectal cancer risk after removal of polyps in fecal immunochemical test based screening.

Background: Colonoscopy surveillance intervals are based on the predicted risk of metachronous colorectal cancer (CRC) after polyp removal. However, risk estimation per polyp subtype is difficult due to the fact that many patients have multiple polyps. To enable risk estimation per polyp subtypes we examined the metachronous CRC risk of subgroups based on presence or absence of co-occurring findings. Methods: Using high-quality screening colonoscopies performed after a positive fecal immunochemical test between 2014 and 2020 within the Dutch CRC screening program, we applied Cox regression analysis to evaluate the association between findings at baseline colonoscopy and metachronous CRCs. For our primary outcome, we appointed each patient to unique subgroups based on removed polyp subtypes that were present or absent at baseline colonoscopy and used the groups without polyps as reference. High-risk subgroups were individuals with high-risk serrated polyps, defined as serrated polyp ≥10 mm, sessile serrated lesions with dysplasia, or traditional serrated adenomas, as well as high-risk adenomas, defined as adenoma ≥10 mm or containing high-grade dysplasia. Findings: In total 253,833 colonoscopies were included. Over a median follow-up of 36 months (IQR, 21-57), we identified 504 metachronous CRCs. Hazard ratios for metachronous CRC was 1.70 (95% CI, 1.07-2.69) for individuals with high-risk serrated polyps without high-risk adenomas, 1.22 (0.96-1.55) for individuals with high-risk adenomas without high-risk serrated polyps, and 2.00 (1.19-3.39) for individuals with high-risk serrated polyps and high-risk adenomas, compared to patients without polyps. Interpretation: Accounting for co-occurring findings, we observed an increased metachronous CRC risk for individuals that had high-risk serrated polyps with the presence of high-risk adenomas, or individuals with high-risk serrated polyps without high-risk adenomas. These findings could provide more evidence to support post-polypectomy surveillance guidelines. Funding: None.

Conversion of unresponsiveness to immune checkpoint inhibition by fecal microbiota transplantation in patients with metastatic melanoma: study protocol for a randomized phase Ib/IIa trial.

BACKGROUND: The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune responses. Furthermore, in trials using fecal microbiota transplantation (FMT) to treat melanoma patients unresponsive to immune checkpoint inhibitors (ICI), complete responses (CR), partial responses (PR), and durable stable disease (SD) have been observed. However, the underlying mechanism determining which patients will or will not respond and what the optimal FMT composition is, has not been fully elucidated, and a discrepancy in microbial taxa associated with clinical response has been observed between studies. Furthermore, it is unknown whether a change in the microbiome itself, irrespective of its origin, or FMT from ICI responding donors, is required for reversion of ICI-unresponsiveness. To address this, we will transfer microbiota of either ICI responder or nonresponder metastatic melanoma patients via FMT. METHODS: In this randomized, double-blinded phase Ib/IIa trial, 24 anti-PD1-refractory patients with advanced stage cutaneous melanoma will receive an FMT from either an ICI responding or nonresponding donor, while continuing anti-PD-1 treatment. Donors will be selected from patients with metastatic melanoma treated with anti-PD-1 therapy. Two patients with a good response (≥ 30% decrease according to RECIST 1.1 within the past 24 months) and two patients with progression (≥ 20% increase according to RECIST 1.1 within the past 3 months) will be selected as ICI responding or nonresponding donors, respectively. The primary endpoint is clinical benefit (SD, PR or CR) at 12 weeks, confirmed on a CT scan at 16 weeks. The secondary endpoint is safety, defined as the occurrence of grade ≥ 3 toxicity. Exploratory endpoints are progression-free survival and changes in the gut microbiome, metabolome, and immune cells. DISCUSSION: Transplanting fecal microbiota to restore the patients' perturbed microbiome has proven successful in several indications. However, less is known about the potential role of FMT to improve antitumor immune response. In this trial, we aim to investigate whether administration of FMT can reverse resistance to anti-PD-1 treatment in patients with advanced stage melanoma, and whether the ICI-responsiveness of the feces donor is associated with its effectiveness. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05251389 (registered 22-Feb-2022). Protocol V4.0 (08-02-2022).

The multitarget fecal immunochemical test versus the fecal immunochemical test for programmatic colorectal cancer screening: a cross-sectional intervention study with paired design.

BACKGROUND: Many screening programs for colorectal cancer (CRC) use the fecal immunochemical test (FIT) to triage individuals for colonoscopy. Although these programs reduce CRC incidence and CRC-related mortality, the detection of advanced precursor lesions (advanced adenomas and advanced serrated polyps) by FIT could be improved. As an alternative for FIT, the antibody-based multitargetFIT (mtFIT) has been proposed. The mtFIT measures three protein markers: hemoglobin, calprotectin, and serpin family F member 2. In a retrospective diagnostic accuracy study in a large colonoscopy-controlled series (n = 1284), mtFIT showed increased sensitivity for advanced neoplasia (AN), at equal specificity, compared to FIT (42.9% versus 37.3%; p = 0.025). This increase was mainly due to a higher sensitivity of mtFIT for advanced adenomas (37.8% versus 28.1% for FIT; p = 0.006). The present mtFIT study aims to prospectively validate these findings in the context of the Dutch national CRC screening program. METHOD: The mtFIT study is a cross-sectional intervention study with a paired design. Eligible subjects for the Dutch FIT-based national CRC screening program are invited to perform mtFIT in addition to FIT. Samples are collected at home, from the same bowel movement, and are shipped to a central laboratory by postal mail. If either one or both tests are positive, participants are referred for colonoscopy. Detailed colonoscopy and pathology data are centrally stored in a national screening database (ScreenIT; Topicus, Deventer, the Netherlands) that is managed by the screening organization, and will be retrieved for this study. We aim to determine the relative sensitivity for AN, comprising of CRC, advanced adenomas and advanced serrated polyps, of mtFIT compared to FIT at an equal positivity rate. Additionally, we will use the Adenoma and Serrated Pathway to Colorectal CAncer model to predict lifetime health effects and costs for programmatic mtFIT- versus FIT-based screening. The target sample size is 13,131 participants. DISCUSSION: The outcome of this study will inform on the comparative clinical utility of mtFIT versus FIT in the Dutch national CRC screening program and is an important step forward in the development of a new non-invasive stool test for CRC screening. TRIAL REGISTRATION: Clinicaltrials.gov ; NCT05314309, registered April 6th 2022, first inclusions March 25th 2022 https://clinicaltrials.gov/ct2/results?cond=&term=NCT05314309&cntry=&state=&city=&dist =.

Longitudinal changes of serum protein N-Glycan levels for earlier detection of pancreatic cancer in high-risk individuals.

BACKGROUND: Surveillance of individuals at risk of developing pancreatic ductal adenocarcinoma (PDAC) has the potential to improve survival, yet early detection based on solely imaging modalities is challenging. We aimed to identify changes in serum glycosylation levels over time to earlier detect PDAC in high-risk individuals. METHODS: Individuals with a hereditary predisposition to develop PDAC were followed in two surveillance programs. Those, of which at least two consecutive serum samples were available, were included. Mass spectrometry analysis was performed to determine the total N-glycome for each consecutive sample. Potentially discriminating N-glycans were selected based on our previous cross-sectional analysis and relative abundances were calculated for each glycosylation feature. RESULTS: 165 individuals ("FPC-cohort" N = 119; Leiden cohort N = 46) were included. In total, 97 (59%) individuals had a genetic predisposition (77 CDKN2A, 15 BRCA1/2, 5 STK11) and 68 (41%) a family history of PDAC without a known genetic predisposition (>10-fold increased risk of developing PDAC). From each individual, a median number of 3 serum samples (IQR 3) was collected. Ten individuals (6%) developed PDAC during 35 months of follow-up; nine (90%) of these patients carried a CDKN2A germline mutation. In PDAC cases, compared to all controls, glycosylation characteristics were increased (fucosylation, tri- and tetra-antennary structures, specific sialic linkage types), others decreased (complex-type diantennary and bisected glycans). The largest change over time was observed for tri-antennary fucosylated glycans, which were able to differentiate cases from controls with a specificity of 92%, sensitivity of 49% and accuracy of 90%. CONCLUSION: Serum N-glycan monitoring may support early detection in a pancreas surveillance program.

Single pharmacy governed denosumab home administration: optimal adherence by means of a fracture liaison service (FLS) and home care collaboration.

Low adherence for denosumab (Dmab, Prolia®) is of major concern. Dutch pharmacies deliveries were calculated recently being 76.5% for a total of 3 injections. INTRODUCTION: Comparing a model where the prescriber maintains responsibility for adherence (model HC1) (Dmab is purchased and dispensed by patient's own community pharmacy and administered through a home care service (HC)) or an all-in-one model where the pharmacist maintains responsibility for the adherence (Dmab is purchased, dispensed, and administered by a pharmacist's HC) (HC2). METHODS: We counted the number of Dmab injections, follow-up appointments on time, Dmab administrations delayed to a maximum of 60 days, the number of Dmab discontinuations, and all causes legally traceable under EU privacy act (EDPR). RESULTS: Home care started by 2014 (study closure in 2021) and included 711 Dmab injections to 256 unique patients: HC1: 536 and HC2: 175 orders. The whole group received on average 2.8 Dmab injections by consistent intervals of about 182 days. Average administration after the latest Dmab injection: 272.8 days (HC1: 362.0 and HC2: 124.0 days). Administration of a subsequent injection > 60 days occurred in 26.6% (HC1: 38.8% and HC2: 6.2%; OR = 9.49). After adjustment for no more than three Dmab injections administered per patient, it occurred in 27.3% (HC1: 51.8% and HC2 4.4%; OR = 23.34). CONCLUSION: It was possible to achieve 94% adherence for Dmab injections treatment just by transferring the complete supply chain to one pharmacy-initiated home care provider after treatment initiation by either a physician or FLS health care professional.

Prospective experimental treatment of colorectal cancer patients based on organoid drug responses.

BACKGROUND: Organoid technology has recently emerged as a powerful tool to assess drug sensitivity of individual patient tumors in vitro. Organoids may therefore represent a new avenue for precision medicine, as this circumvents many of the complexities associated with DNA- or transcriptional-profiling. MATERIALS AND METHODS: The SENSOR trial was a single-arm, single-center, prospective intervention trial to evaluate the feasibility of patient-derived organoids to allocate patients for treatment with off-label or investigational agents. The primary endpoint was an objective response rate of ≥20%. Patients underwent a biopsy for culture before commencing their last round standard of care. Organoids were exposed to a panel of eight drugs and patients were treated after progression on standard-of-care treatment and when a clear signal of antitumor activity was identified in vitro. RESULTS: Sixty-one patients were included and we generated 31 organoids of 54 eligible patients. Twenty-five cultures were subjected to drug screening and 19 organoids exhibited substantial responses to one or more drugs. Three patients underwent treatment with vistusertib and three with capivasertib. Despite drug sensitivity of organoids, patients did not demonstrate objective clinical responses to the recommended treatment. CONCLUSIONS: Organoid technology had limited value as a tool for precision medicine in this patient population because a large fraction of patients could not undergo treatment or because the recommended treatment did not elicit an objective response. We identified several essential parameters, such as the culture success rate, clinical deterioration of patients during standard of care, and rational design of drug panels that need to be accounted for in organoid-guided clinical studies.

Endoscopically removed rectal NETs: a nationwide cohort study.

PURPOSE: Rectal neuroendocrine tumours (NETs) often present as an incidental finding during colonoscopy. Complete endoscopic resection of low-grade NETs up to 10 mm is considered safe. Whether this is also safe for NETs up to 20 mm is unclear. We performed a nationwide study to determine the risk of lymph node and distant metastases in endoscopically removed NETs. METHODS: All endoscopically removed rectal NETs between 1990 and 2010 were identified using the national pathology database (PALGA). Each NET was stratified according to size, grade and resection margin. Follow-up was until February 2016. RESULTS: Between 1990 and 2010, a total of 310 NETs smaller than 20 mm were endoscopically removed. Mean size of NETs was 7.4 mm (SD 3.5). In 49% of NETs (n = 153), no grade (G) could be assessed from the pathology report, 1% was G2 (n = 3), and the remaining NETs were G1. Median follow up was 11.6 years (range 4.9-26.0). During follow-up, 30 patients underwent surgical resection. Lymph node or distant metastasis was seen in 3 patients (1%) which all had a grade 2 NET. Mean time from endoscopic resection to diagnosis of metastases was 6.1 years (95% CI 2.9-9.2). CONCLUSION: No lymph node or distant metastases were seen in endoscopically removed G1 NETs up to 20 mm during the long follow-up of this nationwide study. This adds evidence to the ENET guideline that endoscopic resection of G1 NETs up to 20 mm appears to be safe.

Cumulative risk of skin cancer in patients with Li-Fraumeni syndrome.

Li-Fraumeni syndrome (LFS) is an inherited cancer syndrome, characterized by an early onset of various types of cancers. LFS is associated with a germline mutation in the TP53 gene. The risk of developing skin cancer in patients with LFS is unknown. To evaluate the cumulative risk of skin cancer in patients with LFS and to compare this risk to the general Dutch population. In this retrospective cohort study, all proven TP53 mutation carriers in the Netherlands Cancer Institute were included from their first visit to the Institute until June 2017. Medical charts and pathology reviews cross-referenced with PALGA, the nationwide network and registry of histo- and cytopathology were used to identify incident skin cancers. Cumulative risks were calculated by Kaplan-Meier analysis. Seventy-one patients (59% female) from 33 families were included. Ten patients (14%) developed a total of 19 skin cancers at a median age of 41 (25-65) years. The cumulative risk of skin cancer is 10.4% (95% CI 4.4-23.5%) at age 40, 25.2% (95% CI 12.3-47.6%) at age 60, and a at age 70 this risk is 44.6% (95% CI 22.9-73.9%). The cumulative risks of melanoma and basal cell carcinoma at age 70 are increased compared to the general Dutch population, namely 12.6% (95% CI 3.6-38.4%) and 34.6% (95% CI 15.4-66.2%), respectively. Patients with LFS have an increased risk of developing skin cancer. A dermatological consultation may be considered at least once in individuals with LFS to raise awareness for skin cancer and inform about risk factors.

Low Incidence of Advanced Neoplasia in Serrated Polyposis Syndrome After (Sub)total Colectomy: Results of a 5-Year International Prospective Cohort Study.

INTRODUCTION: Serrated polyposis syndrome (SPS) is accompanied by a substantially increased colorectal cancer (CRC) risk. To prevent or treat CRC in patients with a very high polyp burden, (sub)total colectomy with ileorectal or ileosigmoidal anastomosis is regularly performed. The CRC risk after (sub)total colectomy might be decreased, but evidence is lacking. We aimed to assess the yield of endoscopic surveillance in patients with SPS who underwent (sub)total colectomy. METHODS: For this post hoc analysis, we used prospectively collected data from a large international prospective cohort study. We included patients diagnosed with SPS (World Health Organization type I and/or III) who underwent (sub)total colectomy. Primary endpoint was the cumulative 5-year incidence of CRC and advanced neoplasia (AN). RESULTS: Forty-eight patients (mean age 61 [±7.8]; 52% men) were included and followed up for a median of 4.7 years (interquartile range 4.7-5.1). None of the patients developed CRC during follow-up. Five patients developed AN, corresponding to a cumulative 5-year AN incidence of 13% (95% confidence interval 1.2-23). In 4 patients, AN was diagnosed at the first surveillance endoscopy after study inclusion, and in 1 patient, AN was detected during subsequent rounds of surveillance. The risk of AN was similar for patients with ileorectal and ileosigmoidal anastomosis (logrank P = 0.83). DISCUSSION: (Sub)total colectomy mitigates much of the excess risk of CRC in patients with SPS. Advanced neoplasms are mainly detected at the first endoscopy after (sub)total colectomy. Based on these results, after the first surveillance, intervals might be extended beyond the currently recommended 1-2 years.

A squamous cell carcinoma in a young woman with Lynch syndrome.

Lynch syndrome (LS) is an autosomal-dominant inherited disorder characterized by a predisposition to colorectal cancer and extracolonic cancers (particularly endometrium, ovary, stomach, small bowel, hepatobiliary tract, pancreas, urothelial tract, brain, and skin). Muir-Torre syndrome (MTS) is considered a phenotypical variant of LS, where patients develop sebaceous neoplasms and keratoacanthomas. Currently, only few studies and case reports suggest an association between LS and other skin cancers, such as Bowens' disease, melanoma and squamous cell carcinoma (SCC). In this case-report we describe the case of a 33-year-old woman with LS and a proven MSH2 germline mutation, presenting with a SCC on the right cheek. Immunohistochemistry lacked MSH2 and MSH6 protein staining. The tumor showed a discordance between immunohistochemistry and micro-satellite instability status, for which a clear explanation cannot be provided yet. To conclude whether this pattern is indicative for SCC occurring in LS patients, further analyses of other LS patients presenting with SCC should be carried out. Our patient's young age and skin type (Fitzpatrick phototype VI) suggest a possible link between LS and cutaneous SCC.

Rapid on-site evaluation during endoscopic ultrasound-guided fine-needle aspiration of lymph nodes does not increase diagnostic yield: A randomized, multicenter trial.

OBJECTIVES: Studies on the impact of rapid on-site evaluation (ROSE) during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of lymph nodes are retrospective and have shown conflicting results. We aimed to compare the diagnostic yield of EUS-FNA of lymph nodes with ROSE (ROSE+) and without ROSE (ROSE-). METHODS: This was a multicenter, randomized controlled trial. Consecutive patients who were scheduled to undergo EUS-FNA of mediastinal or abdominal lymph nodes were randomized to ROSE+ or ROSE-. In the ROSE+ group, the number of passes was dictated by the on-site cytotechnician. In the ROSE- group, five passes were performed without interference from the cytotechnician. All samples were reviewed by a single-expert cytopathologist, blinded to group allocation. Primary endpoint was diagnostic yield with and without ROSE. RESULTS: After inclusion of 90 patients, interim analysis showed futility of study continuation since diagnostic yield of ROSE+ and ROSE- were comparable. A total of 91 patients were randomized to ROSE+ (N = 45) or ROSE- (N = 46). Diagnostic yield of ROSE+ and ROSE- and diagnostic accuracy were comparable: 93.3% vs. 95.7% (P = 0.68) and 97.6% vs. 93.2% (P = 0.62), respectively. Two major complications (one per group) occurred (p = 0.99). ROSE- patients more often reported self-limiting post-procedural pain (p < 0.001). Median procedure time for ROSE+ (20 min) and ROSE- (23 min) was comparable (P = 0.06). Median time to review slides in the ROSE- group (12:47 min) was longer than with ROSE+ (7:52 min) (P < 0.001). Mean costs of ROSE- and ROSE+ were comparable: €938.29 (±172.70) vs. €945.98 (±223.38) (P = 0.91), respectively. CONCLUSIONS: Diagnostic yield and accuracy of EUS-FNA of mediastinal and abdominal lymph nodes with and without ROSE are comparable. Time needed to review slides was shorter and post-procedural pain was less often reported in the ROSE+ group. Based on the primary outcome, the implementation of ROSE during EUS-FNA of mediastinal and abdominal lymph nodes cannot be advised. (Dutch Trial Register: NTR4876).

[Early discharge possible in acute upper gastrointestinal bleeding; new study results require adaptation of Dutch guideline]. / Snel ontslag mogelijk bij acute bovenste-tractusdigestivusbloeding.

Acute upper gastrointestinal bleeding is still an important emergency situation with an incidence of 48-62 per 100,000 adults per year in the Netherlands. An international multicentre prospective study evaluated different risk scoring systems for patients presenting with upper gastrointestinal bleeding. The authors showed that patients with a Glasgow Blatchford score of 0 or 1 could be safely discharged without endoscopy. Thirty-day all-cause mortality in this group was 0.4%. In the current Dutch guideline, there is no clear advice on management of low-risk patients. The new guideline is expected in 2017 and should include this clear advice of discharging low-risk patients (Glasgow Blatchford score ≤ 1). It can therefore be concluded that with optimal selection about 20% of all patients presenting to the emergency room with acute upper gastrointestinal bleeding can be discharged the same day without intervention.

Gastrointestinal diseases and their oro-dental manifestations: Part 4: Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant inherited disorder, caused by germline mutations in the LKB1 tumour suppressor gene. It is clinically characterised by distinct perioral mucocutaneous pigmentations, gastrointestinal polyposis and an increased cancer risk in adult life. Hamartomatous polyps can develop already in the first decade of life and may cause various complications, including abdominal pain, bleeding, anaemia, and acute intestinal obstruction. Furthermore, patients have an increased risk for developing cancer, both in the gastrointestinal tract as in other organs. The medical management of PJS mainly consists of surveillance and treatment of the hamartomatous polyps. Upper and lower endoscopies are recommended for surveillance and removal of PJS polyps in the stomach and the small and large intestine. Furthermore, the high risk for pancreatic cancer justifies surveillance of the pancreatic region by MRI or endoscopic ultrasound. In addition, breast and gynaecological surveillance is recommended for female patients. Although the genetic defect underlying PJS is known, the pathogenesis of hamartomas and carcinomas is unclear. More insight into the molecular background of PJS might lead to targeted therapies for patients with this syndrome.

Clinical risk factors of colorectal cancer in patients with serrated polyposis syndrome: a multicentre cohort analysis.

OBJECTIVE: Serrated polyposis syndrome (SPS) is accompanied by an increased risk of colorectal cancer (CRC). Patients fulfilling the clinical criteria, as defined by the WHO, have a wide variation in CRC risk. We aimed to assess risk factors for CRC in a large cohort of patients with SPS and to evaluate the risk of CRC during surveillance. DESIGN: In this retrospective cohort analysis, all patients with SPS from seven centres in the Netherlands and two in the UK were enrolled. WHO criteria were used to diagnose SPS. Patients who only fulfilled WHO criterion-2, with IBD and/or a known hereditary CRC syndrome were excluded. RESULTS: In total, 434 patients with SPS were included for analysis; 127 (29.3%) were diagnosed with CRC. In a per-patient analysis ≥1 serrated polyp (SP) with dysplasia (OR 2.07; 95% CI 1.28 to 3.33), ≥1 advanced adenoma (OR 2.30; 95% CI 1.47 to 3.67) and the fulfilment of both WHO criteria 1 and 3 (OR 1.60; 95% CI 1.04 to 2.51) were associated with CRC, while a history of smoking was inversely associated with CRC (OR 0.36; 95% CI 0.23 to 0.56). Overall, 260 patients underwent surveillance after clearing of all relevant lesions, during which two patients were diagnosed with CRC, corresponding to 1.9 events/1000 person-years surveillance (95% CI 0.3 to 6.4). CONCLUSION: The presence of SPs containing dysplasia, advanced adenomas and/or combined WHO criteria 1 and 3 phenotype is associated with CRC in patients with SPS. Patients with a history of smoking show a lower risk of CRC, possibly due to a different pathogenesis of disease. The risk of developing CRC during surveillance is lower than previously reported in literature, which may reflect a more mature multicentre cohort with less selection bias.