Screening and surveillance for hereditary colorectal cancer

Hereditary colorectal cancer is a type of cancer that is caused by a genetic mutation. Individuals with a family history of colorectal cancer, or who have a known hereditary syndrome, are at an increased risk of developing the disease. Screening and surveillance are important tools for managing the risk of hereditary colorectal cancer. Screening involves a combination of tests that can detect precancerous or cancerous changes in the colon and rectum. Surveillance involves regular follow-up examinations to monitor disease progression and to identify new developments. The frequency and type of screening and surveillance tests may vary depending on an individual's risk factors, genetic profile, and medical history. However, early detection and treatment of hereditary colorectal cancer can significantly improve patient outcomes and reduce mortality rates. By implementing comprehensive screening and surveillance strategies, healthcare providers can help individuals at risk of hereditary colorectal cancer to receive timely interventions and make informed decisions about their health. Specific examples of screening and surveillance tests for hereditary colorectal cancer include colonoscopy, genetic testing, and imaging tests. In this review article, we will discuss detailed screening and surveillance of hereditary colorectal cancer.

Universal Screening for Lynch Syndrome Compared with Pedigree-Based Screening: 10-Year Experience in a Tertiary Hospital

PURPOSE

Universal screening for Lynch syndrome (LS) refers to routine tumor testing for microsatellite instability (MSI) among all patients with colorectal cancer (CRC). Despite its widespread adoption, real-world data on the yield is lacking in Korean population. We studied the yield of adopting universal screening for LS in comparison with pedigree-based screening in a tertiary center.

MATERIALS AND METHODS

CRC patients from 2007-2018 were reviewed. Family histories were obtained and were evaluated for hereditary nonpolyposis colorectal cancer (HNPCC) using Amsterdam II criteria. Tumor testing for MSI began in 2007 and genetic testing was offered using all available clinicopathologic data. Yield of genetic testing for LS was compared for each approach and step.

RESULTS

Of the 5,520 patients, tumor testing was performed in 4,701 patients (85.2%) and family histories were obtained from 4,241 patients (76.8%). Hereditary CRC (LS or HNPCC) was present in 69 patients (1.3%). MSI-high was present in 6.9%, and 25 patients had confirmed LS. Genetic testing was performed in 41.2% (47/114) of MSI-high patients, out of which 40.4% (19/47) were diagnosed with LS. There were six additional LS patients found outside of tumor testing. For pedigree-based screening, Amsterdam II criteria diagnosed 55 patients with HNPCC. Fifteen of these patients underwent genetic testing, and 11 (73.3%) were diagnosed with LS. Two patients without prior family history were diagnosed with LS and relied solely on tumor testing results.

CONCLUSION

Despite widespread adoption of routine tumor testing for MSI, this is not a fail-safe approach to screen all LS patients. Obtaining a thorough family history in combination with universal screening provides a more comprehensive 'universal' screening method for LS.

Effectiveness of a surveillance program of upper endoscopy for upper gastrointestinal cancers in Lynch syndrome patients

BACKGROUND AND AIMS

Lynch syndrome (LS) is the most common cause of hereditary colorectal cancer and is associated with an increased lifetime risk of gastric and duodenal cancers of 8-16% and 7%, respectively; therefore, we aim to describe an esophagogastroduodenoscopy (EGD) surveillance program for upper gastrointestinal (GI) precursor lesions and cancer in LS patients.

METHODS

Patients who either had positive genetic testing or met clinical criteria for LS who had a surveillance EGD at our institution from 1996 to 2017 were identified. Patients were included if they had at least two EGDs or an upper GI cancer detected on the first surveillance EGD. EGD and pathology reports were extracted manually.

RESULTS

Our cohort included 247 patients with a mean age of 47.1 years (SD 12.6) at first EGD. Patients had a mean of 3.5 EGDs (range 1-16). Mean duration of follow-up was 5.7 years. Average interval between EGDs was 2.3 years. Surveillance EGD detected precursor lesions in 8 (3.2%) patients, two (0.8%) gastric cancers and two (0.8%) duodenal cancers. Two interval cancers were diagnosed: a duodenal adenocarcinoma was detected 2 years, 8 months after prior EGD and a jejunal adenocarcinoma was detected 1 year, 9 months after prior EGD.

CONCLUSIONS

Our data suggest that surveillance EGD is a useful tool to help detect precancerous and cancerous upper GI lesions in LS patients. To our knowledge, this is the first study to examine a program of surveillance EGDs in LS patients. More data are needed to determine the appropriate surveillance interval.

Identification of Lynch Syndrome

Lynch syndrome (LS) is an autosomal dominant hereditary cancer syndrome caused by pathogenic germline variants (PGV) in any of the 4 DNA mismatch repair (MMR) genes, MLH1, MSH2, MSH6, and PMS2, or deletions in EPCAM. LS leads to an increased risk of intestinal and extraintestinal cancers, of which colorectal and endometrial cancers are the most common. Individuals at risk for LS can be identified by using clinical criteria, prediction models, and universal tumor testing. Understanding each of these tools, including limitations and mimics of LS, is essential to the early identification of at-risk individuals.

Upper Tract Urothelial Carcinoma in the Lynch Syndrome Tumour Spectrum: A Comprehensive Overview from the European Association of Urology - Young Academic Urologists and the Global Society of Rare Genitourinary Tumors

CONTEXT

Upper tract urothelial carcinoma (UTUC) represents the third most frequent malignancy in Lynch syndrome (LS).

OBJECTIVE

To systematically review the available literature focused on incidence, diagnosis, clinicopathological features, oncological outcomes, and screening protocols for UTUC among LS patients.

EVIDENCE ACQUISITION

Medline, Scopus, Google Scholar, and Cochrane Database of Systematic Reviews were searched up to May 2021. Risk of bias was determined using the modified Cochrane tool. A narrative synthesis was undertaken.

EVIDENCE SYNTHESIS

Overall, 43 studies between 1996 and 2020 were included. LS patients exhibited a 14-fold increased risk of UTUC compared with the general population, which further increased to 75-fold among hMSH2 mutation carriers. Patients younger than 65 yr and patients with personal or family history of LS-related cancers should be referred to molecular testing on tumour specimen and subsequent genetic testing to confirm LS. Newly diagnosed LS patients may benefit from a multidisciplinary management team including gastroenterologist and gynaecologist specialists, while genetic counselling should be recommended to first-degree relatives (FDRs). Compared with sporadic UTUC individuals, LS patients were significantly younger (p = 0.005) and exhibited a prevalent ureteral location (p = 0.01). Radical nephroureterectomy was performed in 75% of patients (5-yr cancer-specific survival: 91%). No consensus on screening protocols for UTUC was achieved: starting age varied between 25-35 and 50 yr, while urinary cytology showed sensitivity of 29% and was not recommended for screening.

CONCLUSIONS

Urologists should recognise patients at high risk for LS and address them to a comprehensive diagnostic pathway, including molecular and genetic testing. Newly diagnosed LS patients should be referred to a multidisciplinary team, while genetic counselling should be recommended to FDRs.

PATIENT SUMMARY

In this systematic review, we analysed the existing literature focused on upper tract urothelial carcinoma (UTUC) among patients with Lynch syndrome (LS). Our purpose is to provide a comprehensive overview of LS-related UTUC to reduce misdiagnosis and improve patient prognosis.

Deficient DNA mismatch repair and persistence of SARS-CoV-2 RNA shedding: a case report of hereditary nonpolyposis colorectal cancer with COVID-19 infection

BACKGROUND

Several independent risk factors have been reported to influence viral shedding following COVID-19 infection, but the influence of host-related molecular factors has not yet been described. We report a case of a cancer patient with Lynch syndrome (hereditary nonpolyposis colorectal cancer, HNPCC) who manifested SARS-CoV-2 PCR (polymerase chain reaction) positivity for at least 54 days after contracting mild COVID-19 illness. We propose that deficient mismatch repair (MMR) may play a role in the prolonged SARS-CoV-2 RNA shedding.

CASE PRESENTATION

A patient with Lynch syndrome was under surveillance for metastatic adenocarcinoma after completing palliative chemotherapy in October 2019. Between the period of April 2020 to June 2020, he was admitted multiple times to address several clinical needs mainly related to his underlying malignancy. These included progressive disease observed in the aortocaval lymph nodes leading to recurrent episodes of upper gastrointestinal bleeding, dehydration resulting in acute kidney injury and a short-lived episode of pyrexia. A SARS-CoV-2 PCR of the nasopharyngeal swab (NPS) was positive at his initial admission with mild COVID-19 symptoms. He remained positive on subsequent admissions when tested routinely for SARS-CoV-2 without demonstrating any apparent clinical features of COVID-19 infection. The MMR pathway, a component of DNA damage response (DDR), is impaired in Lynch syndrome due to an inherited genetic mutation. This pathway is also required for viral clearance from the host cells following certain RNA viral infections like influenza virus and other coronaviridae. Here we provide a current understanding of the importance of DDR deficiencies in the clearance of RNA virus and suggest how this may play a similar role in the clearance of COVID-19, as evident in our case that demonstrated persistent positivity.

CONCLUSION

The importance of understanding the scientific basis of extended viral shedding during the COVID-19 pandemic is now centre-stage in the establishment of robust track and trace services to allow the recovery and function of societies and economies. This patient with Lynch syndrome recovered from infection but had prolonged viral positivity, which might merit further investigation to better understand the effect of this condition on infection duration and outcome.

Lynch Syndrome in Thai Endometrial Cancer Patients

BACKGROUND

Lynch syndrome increases lifetime risk of endometrial cancer to 40-60%. Screening with molecular tumor testing for mismatch repair (MMR) proteins have been recommended. This study aims to evaluate the incidence of MMR deficiency and germline mutation in endometrial cancer Thai patients.

METHODS

Immunohistochemistry for MMR proteins, including MLH1, MSH2, MSH6 and PMS2 were tested in 166 surgical specimens. Patients who had MMR deficiencies were offered genetic counseling and a germline testing using gene-panel next generation sequencing.

RESULTS

Fifty-eight of 166 patients (34.9%) had one or more MMR deficiencies which were: MLH1 and PMS2 in 42 patients (25.3%), MSH2 and MSH6 in 11 patients (6.6%), and MSH6 in 5 patients (3.0%). Of the 40 patients (24.1%) who met the revised Bethesda guidelines, 19 patients (47.5%) had MMR deficiency. In contrast, MMR deficiency was found in 39 of the 126 patients (31.0%) who did not meet the revised Bethesda guidelines. A total of 27 patients with MMR deficiencies agreed to have germline genetic testing. Germline MMR mutations were detected in 5 patients (18.5%) including MSH6 (n=2), PMS2 (n=2), and MLH1 mutations (n=1). Incidental germline mutations in other genes were detected in 3 patients (1 BRCA1, 1 PTEN, and 1 BARD1). Among 5 Lynch syndrome patients, 2 patients (40%) did not meet the revised Bethesda guidelines. Eight patients who met the revised Bethesda Guidelines but having MMR proficiency had genetic testing, but no germline mutation was detected.

CONCLUSION

MMR deficiencies were detected in 34.9% of the endometrial cancer patients. Germline mutations were diagnosed in 3.0% of this cohort (5/166 patients). Lynch syndrome screening with MMR immunohistochemistry should be considered in all patients regardless of personal or family history of Lynch syndrome-related cancers.

Intussusception secondary to signet ring cell adenocarcinoma in adolescent

Despite the overall decrease in incidence and mortality rates for older adults, colorectal cancer in young adults is increasing. We present a case of a 15-year-old male who presented with 1.5 weeks of intermittent, sharp, severe right-sided abdominal pain. Abdominal radiograph demonstrated an air-fluid level within the right hemiabdomen. Computed tomography demonstrated marked wall thickening and a mass at the junction of the ascending colon and hepatic flexure causing obliteration of the lumen with a fluid-filled, dilated ascending colon. Follow-up ultrasonography demonstrated a 5.9 × 3.9 cm targetoid lesion in the right upper quadrant concerning for intussusception. Contrast enema revealed failure of contrast filling beyond the hepatic flexure due to a lobulated central filling defect surrounded by a claw-like contrast extension. Pathology of the polypoid lesion revealed poorly differentiated signet ring cell adenocarcinoma of the colon at the hepatic flexure. Despite its rarity, this case elucidates the need to consider colorectal carcinoma in adolescent and young adult patients who present with recurrent abdominal signs and symptoms.

A War on Two Fronts: Cancer Care in the Time of COVID-19

Initial reports suggest that COVID-19 can be particularly lethal in patients with cancer. This commentary discusses how to balance a delay in cancer diagnosis or treatment against the risk for a potential COVID-19 exposure, mitigate the risks for significant care disruptions associated with social distancing behaviors, and manage the appropriate allocation of limited health care resources in this unprecedented time of health care crisis.

[Hereditary colon cancer in Lynch syndrome/HNPCC syndrome in Germany]

BACKGROUND

Hereditary nonpolyposis colorectal cancer (Lynch/HNPCC syndrome) is based on a germline mutation inducing increased occurrence of colorectal cancer and extracolonic carcinomas in young age. The German HNPCC consortium aims to increase awareness for detection of hereditary colon cancer among patients and physicians.

OBJECTIVES

Reliable detection of HNPCC patients is based on a thorough documentation of patients' medical history and on further diagnostics delivered by human genetics and surgical pathology. This manuscript presents a standardized diagnostic concept.

METHODS

Relevant literature is reviewed and discussed and diagnostic parameters are outlined. In addition, operating figures of the German HNPCC consortium are presented.

RESULTS

The German HNPCC consortium is based on an efficient cooperation between clinical physicians, human geneticists, and surgical pathologists. After a funding period from the Deutsche Krebshilfe, HNPCC diagnostics and preventive medical examinations were transferred into standard care in Germany. In total, 5770 families (8873 patients) were included in HNPCC diagnostics. To date, in 1296 families, mutations of the MLH1-, MSH2-, MSH6-, PMS2-, or EPCAM-gene have been detected. Furthermore, 612 pathogenic variants and 325 variants of unknown significance were found.

CONCLUSIONS

Reliable detection of HNPCC patients is based on a standardized diagnostic concept, which has been established within the German HNPCC consortium.

Oral tongue cancer in a patient with hereditary nonpolyposis colorectal cancer: A case report and review of the literature

Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disorder characterized by mutations of mismatch repair genes leading to the early development of multiple malignancies. The most common malignancy is colorectal cancer but there is a strong association with malignancies of the ovary, endometrium, small intestine, stomach, skin, brain, and pancreas. We report a case of a 35-year-old female with a history of known HNPCC who presented with adenocarcinoma of the small intestine as well as a synchronous oral tongue squamous cell carcinoma. The patient underwent a combined oncologic surgery involving a hemiglossectomy, selective neck dissection, and partial small bowel resection. Despite the wide range of malignancies seen in patients with HNPCC, no cases of oral cavity cancer have previously been reported. This represents the first case in the literature of oral cavity cancer in a patient with HNPCC.

Phenotypic and genotypic heterogeneity of Lynch syndrome: a complex diagnostic challenge

Lynch syndrome is the hereditary disorder that most frequently predisposes to colorectal cancer as well as predisposing to a number of extracolonic cancers, most prominently endometrial cancer. It is caused by germline mutations in the mismatch repair genes. Both its phenotype and genotype show marked heterogeneity. This review gives a historical overview of the syndrome, its heterogeneity, its genomic landscape, and its implications for complex diagnosis, genetic counseling and putative implications for immunotherapy.

Lack of association between screening interval and cancer stage in Lynch syndrome may be accounted for by over-diagnosis; a prospective Lynch syndrome database report

Background

Recent epidemiological evidence shows that colorectal cancer (CRC) continues to occur in carriers of pathogenic mismatch repair (path_MMR) variants despite frequent colonoscopy surveillance in expert centres. This observation conflicts with the paradigm that removal of all visible polyps should prevent the vast majority of CRC in path_MMR carriers, provided the screening interval is sufficiently short and colonoscopic practice is optimal.

Methods

To inform the debate, we examined, in the Prospective Lynch Syndrome Database (PLSD), whether the time since last colonoscopy was associated with the pathological stage at which CRC was diagnosed during prospective surveillance. Path_MMR carriers were recruited for prospective surveillance by colonoscopy. Only variants scored by the InSiGHT Variant Interpretation Committee as class 4 and 5 (clinically actionable) were included. CRCs detected at the first planned colonoscopy, or within one year of this, were excluded as prevalent cancers.

Results

Stage at diagnosis and interval between last prospective surveillance colonoscopy and diagnosis were available for 209 patients with 218 CRCs, including 162 path_MLH1, 45 path_MSH2, 10 path_MSH6 and 1 path_PMS2 carriers. The numbers of cancers detected within < 1.5, 1.5–2.5, 2.5–3.5 and at > 3.5 years since last colonoscopy were 36, 93, 56 and 33, respectively. Among these, 16.7, 19.4, 9.9 and 15.1% were stage III–IV, respectively (p = 0.34). The cancers detected more than 2.5 years after the last colonoscopy were not more advanced than those diagnosed earlier (p = 0.14).

Conclusions

The CRC stage and interval since last colonoscopy were not correlated, which is in conflict with the accelerated adenoma-carcinoma paradigm. We have previously reported that more frequent colonoscopy is not associated with lower incidence of CRC in path_MMR carriers as was expected. In contrast, point estimates showed a higher incidence with shorter intervals between examinations, a situation that may parallel to over-diagnosis in breast cancer screening. Our findings raise the possibility that some CRCs in path_MMR carriers may spontaneously disappear: the host immune response may not only remove CRC precursor lesions in path_MMR carriers, but may remove infiltrating cancers as well. If confirmed, our suggested interpretation will have a bearing on surveillance policy for path_MMR carriers.

Clinician-Stakeholders' Perspectives on Using Patient Portals to Return Lynch Syndrome Screening Results

Test results for genetic conditions, such as Lynch Syndrome (LS), have traditionally been returned by genetic counselors or other providers who can explain results implications and provide psychosocial support. Returning genetic results through an Electronic Health Record's patient portal may increase the efficiency of returning results and could activate patient follow-up; however, stakeholder input is necessary to determine acceptability and appropriate implementation for LS. Twenty interviews were conducted with clinicians from six specialties involved in LS screening that represent a range of settings. Data were analyzed using directed content analysis and thematic analysis across content categories. Participants felt that patient portals could supplement personal calls, but the potential sensitive nature of LS screening results indicated the need for caution. Others felt that LS results could be returned through portals if there were clear explanations of the result, reputable additional information available within the portal, urging follow up confirmatory testing, and a referral to a genetics specialist. Patient portals were seen as helpful for prompting patient follow-up and providing resources to notify at-risk family members. There is potential for patient portals to return LS screening and other genetic results, however we raise several issues to resolve before implementation is warranted.

Hereditary Colorectal Cancer Syndromes

Awareness of hereditary colorectal cancer syndromes is important to facilitate their identification because affected patients are at increased risk for early onset, synchronous, and metachronous colorectal malignancies, and certain extracolonic malignancies depending on the syndrome. Identification of an affected individual allows for screening and early interventions for patients and their at-risk kindred. Genetic counseling and testing is important to the care of these patients. As knowledge of the genetic basis of these syndromes grows, unique genotype-phenotype profiles allow clinicians to tailor surveillance and treatment strategies based on individual risk.

[Differential indications for ileoanal pouch anastomosis : Ulcerative colitis, familial adenomatous polyposis, synchronous colorectal cancer - Crohn's disease, constipation]

Ileoanal pouch anastomosis is the procedure of choice for patients with drug refractory ulcerative colitis, indeterminate colitis and familial adenomatous polyposis (FAP). In selected patient groups this procedure is a treatment option for patients with Crohn's disease, hereditary nonpolyposis colorectal cancer (HNPCC), synchronous colorectal cancer and for severe colorectal constipation refractory to conservative drug treatment. The pouch procedure provides the opportunity to avoid a permanent ileostomy. The majority of surgeons prefer the ileal J‑pouch as the construction is the easiest to perform and complications and dysfunction rates are low. Due to functional reasons most pouch surgeons favor a circular stapled ileoanal pouch anastomosis. The more radical proctocolectomy can produce sensory defects in the anal canal with subsequent soiling and incontinence. Studies have shown that even after proctocolectomy residual rectal mucosa was found in the anal canal. Therefore, the functionally important anorectal transitional zone should be preserved if possible. Ulcerative colitis can be "healed" with proctocolectomy; however, pouchitis can still occur in one third of the patients. Patients must be informed about the risk of pouchitis and a multidisciplinary monitoring and treatment strategy must be available. In Crohn's disease the ileoanal pouch survival rate of 80% in the long-term follow-up is surprisingly good despite an increased postoperative complication rate. The anal pouch anastomosis is the standard operation in patients with drug refractory ulcerative colitis, indeterminate colitis and FAP. Synchronous colorectal cancer, HNPCC and severe therapy refractive constipation represent rare indications for proctocolectomy where decisions must be made on an individual basis.

Molecular Screening for Lynch Syndrome in Young Patients With Colorectal Adenomas

BACKGROUND

The frequency of mismatch repair (MMR) deficiency (dMMR) in patients < 50 years with adenomas without a known germline mutation is unknown. Our aim was to define the frequency of dMMRs in adenomas from patients aged < 50 years.

PATIENTS AND METHODS

We identified all patients aged 18 to 49 years who had undergone colonoscopy at Memorial Sloan Kettering Cancer Center from 2008 to 2013 and were identified as having tubular, villous, or tubulovillous adenomas on pathology. Patients with a personal history of colorectal cancer, polyposis syndrome, or inflammatory bowel disease before colonoscopy were excluded. Age, demographic data, family history of cancer, personal history of cancer, use of radiation, reason for colonoscopy, and colonoscopy findings were recorded. Polyps were stained using immunohistochemistry for MLH1, MSH2, MSH6, and PMS2 proteins.

RESULTS

A total of 208 patients with 266 polyps were identified. Of the 266 polyps, 259 could be stained. Of the 208 patients, 82 (40%) were men; their mean age was 44 years. The indication for colonoscopy was screening for 120, diagnostic for 75, and therapeutic for 15. Of the 259 examined polyps, 246 (95%) were tubular adenomas and 13 were tubulovillous adenomas (5%). One patient (0.4%) was found to have dMMRs in 1 polyp. This patient was a 42-year-old woman with a history of endometrial cancer who had undergone colonoscopy for hematochezia. A 15-mm transverse tubular adenoma was found that was deficient in MLH1 and PMS2.

CONCLUSION

Our results indicate that routine screening of polyps in patients aged < 50 years old is not an effective tool for identifying Lynch syndrome carriers.

The mRNA level of MLH1 in peripheral blood is a biomarker for the diagnosis of hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is caused by functional defects in mismatch repair (MMR) genes, including mutL homolog 1 (MLH1) and mutS homolog 2 (MSH2). This study aimed to assess whether the mRNA expression of MLH1 in peripheral blood could be used as a biomarkers for the diagnosis of HNPCC. The mRNA level of MLH1 was determined in 19 HNPCC families (46 members) using real-time quantitative polymerase chain reaction (qPCR). The mRNA levels of MLH1 in HNPCC were significantly lower than controls (P < 0.001). Receiver operating characteristic (ROC) curve showed a high diagnostic value of the mRNA level of MLH1 for the diagnosis of HNPCC with the area under curve of 0.858. At an optimal cut-off value (0.511), the mRNA level of MLH1 had a sensitivity of 81.3% and a specificity of 86.7% for distinguishing HNPCC from controls. In conclusion, the mRNA expression of MLH1 in peripheral blood may serve as a biomarker for the diagnosis of HNPCC.

Hereditary Colorectal Cancer: Genetics and Screening

Colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancer death in men and women in the United States. About 30% of patients with CRC report a family history of CRC. However, only 5% of CRCs arise in the setting of a well-established mendelian inherited disorder. In addition, serrated polyposis is a clinically defined syndrome with multiple serrated polyps in the colorectum and an increased CRC risk for which the genetics are unknown. This article focuses on genetic and clinical aspects of Lynch syndrome, familial adenomatous polyposis, and MUTYH-associated polyposis.

Pancreatic intraductal papillary mucinous neoplasm in a patient with Lynch syndrome

Intraductal papillary mucinous neoplasm (IPMN) is a mucin-producing epithelial neoplasm that carries a risk of progression to invasive pancreatic ductal adenocarcinoma. Lynch syndrome is an autosomal dominant condition caused by germline mutations in mismatch repair genes such as MSH2 that lead to microsatellite instability and increased risk of tumor formation. Although families with Lynch syndrome have an increased risk of pancreatic cancer, a clear connection between Lynch syndrome and IPMN has not been drawn. We present a report of a 58 year-old Caucasian woman with multiple cancers and a germline mutation of MSH2 consistent with Lynch syndrome. A screening abdominal computed tomography scan revealed a dilated main pancreatic duct and cystic ductular structure in the uncinate process that were consistent with IPMN of the main pancreatic duct on excision. Immunohistochemistry and polymerase chain reaction of the patient’s pancreas specimen did not reveal microsatellite instability or mismatch repair gene loss of expression or function. Our findings may be explained by the fact that loss of mismatch repair function and microsatellite instability is a late event in neoplastic transformation. Given the relative rarity of main duct IPMN, its appearance in the setting of somatic MSH2 mutation suggests that IPMN may fit into the constellation of Lynch syndrome related malignancies.

Knowledge of and practice patterns for hereditary colorectal cancer syndromes in korean surgical residents

Purpose

Obtaining a detailed family history through detailed pedigree is essential in recognizing hereditary colorectal cancer (CRC) syndromes. This study was performed to assess the current knowledge and practice patterns of surgery residents regarding familial risk of CRC.

Methods

A questionnaire survey was performed to evaluate the knowledge and the level of recognition for analyses of family histories and hereditary CRC syndromes in 62 residents of the Department of Surgery, Seoul National University Hospital. The questionnaire consisted of 22 questions regarding practice patterns for, knowledge of, and resident education about hereditary CRC syndromes.

Results

Two-thirds of the residents answered that family history should be investigated at the first interview, but only 37% of them actually obtained pedigree detailed family history at the very beginning in actual clinical practice. Three-quarters of the residents answered that the quality of family history they obtained was poor. Most of them could diagnose hereditary nonpolyposis colorectal cancer and recommend an appropriate colonoscopy surveillance schedule; however, only 19% knew that cancer surveillance guidelines differed according to the family history. Most of our residents lacked knowledge of cancer genetics, such as causative genes, and diagnostic methods, including microsatellite instability test, and indicated a desire and need for more education regarding hereditary cancer and genetic testing during residency.

Conclusion

This study demonstrated that surgical residents' knowledge of hereditary cancer was not sufficient and that the quality of the family histories obtained in current practice has to be improved. More information regarding hereditary cancer should be considered in education programs for surgery residents.

Hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is a class of autosomal dominant genetic disease. Main clinical characteristics of HNPCC include early onset age, more common in the right colon, and concomitant with simultaneous or metachronous extracolonic cancers, including endometrial cancer, stomach cancer, and ovarian cancer. However, the prognosis of HNPCC is better than sporadic colorectal cancer. Screening and intervention for HNPCC among high-risk pedigree population can effectively reduce the cancer incidence and mortality. In this article we will review the pathogenesis, epidemiology, diagnosis, screening, prevention and treatment of HNPCC.

Sulindac modulates secreted protein expression from LIM1215 colon carcinoma cells prior to apoptosis

Colorectal cancer (CRC) is a major cause of mortality in Western populations. Growing evidence from human and rodent studies indicate that nonsteroidal anti-inflammatory drugs (NSAIDs) cause regression of existing colon tumors and act as effective chemopreventive agents in sporadic colon tumor formation. Although much is known about the action of the NSAID sulindac, especially its role in inducing apoptosis, mechanisms underlying these effects is poorly understood. In previous secretome-based proteomic studies using 2D-DIGE/MS and cytokine arrays we identified over 150 proteins released from the CRC cell line LIM1215 whose expression levels were dysregulated by treatment with 1mM sulindac over 16h; many of these proteins are implicated in molecular and cellular functions such as cell proliferation, differentiation, adhesion, angiogenesis and apoptosis (Ji et al., Proteomics Clin. Appl. 2009, 3, 433-451). We have extended these studies and describe here an improved protein/peptide separation strategy that facilitated the identification of 987 proteins and peptides released from LIM1215 cells following 1mM sulindac treatment for 8h preceding the onset of apoptosis. This peptidome separation strategy involved fractional centrifugal ultrafiltration of concentrated cell culture media (CM) using nominal molecular weight membrane filters (NMWL 30K, 3K and 1K). Proteins isolated in the >30K and 3-30K fractions were electrophoretically separated by SDS-PAGE and endogenous peptides in the 1-3K membrane filter were fractioned by RP-HPLC; isolated proteins and peptides were identified by nanoLC-MS-MS. Collectively, our data show that LIM1215 cells treated with 1mM sulindac for 8h secrete decreased levels of proteins associated with extracellular matrix remodeling (e.g., collagens, perlecan, syndecans, filamins, dyneins, metalloproteinases and endopeptidases), cell adhesion (e.g., cadherins, integrins, laminins) and mucosal maintenance (e.g., glycoprotein 340 and mucins 5AC, 6, and 13). A salient finding of this study was the increased proteolysis of cell surface proteins following treatment with sulindac for 8h (40% higher than from untreated LIM1215 cells); several of these endogenous peptides contained C-terminal amino acids from transmembrane domains indicative of regulated intramembrane proteolysis (RIP). Taken together these results indicate that during the early-stage onset of sulindac-induced apoptosis (evidenced by increased annexin V binding, dephosphorylation of focal adhesion kinase (FAK), and cleavage of caspase-3), 1mM sulindac treatment of LIM1215 cells results in decreased expression of secreted proteins implicated in ECM remodeling, mucosal maintenance and cell-cell-adhesion. This article is part of a Special Issue entitled: An Updated Secretome.

Serum microRNAs as promising novel biomarkers for hereditary nonpolyposis colorectal cancer

AIM: To screen and identify serum microRNAs (miRNAs) that might be used as promising biomarkers for hereditary nonpolyposis colorectal cancer using miRNA array and qRT-PCR.

METHODS: Four serum samples from patients with hereditary nonpolyposis colorectal cancer and three serum samples from healthy controls were used to identify potential markers by miRNA array. The results of miRNA array were confirmed by qRT-PCR.

RESULTS: We found 57 up-regulated miRNAs and 30 down-regulated miRNAs by miRNA array, and 8 miRNAs were chosen for further analysis. Three target gene prediction programs were used to predict target genes of these 8 miRNAs, and 294 genes were predicted, all of which were target genes of mir-20a-5p, mir-548b-5p and mir-548as-3p. qPCR analysis confirmed that serum mir-548as-3p was significantly higher in patients with hereditary nonpolyposis colorectal cancer.

CONCLUSION: Our study demonstrates that serum miRNAs are differentially expressed in patients with hereditary nonpolyposis colorectal cancer, and that mir-548as-3p can potentially serve as a noninvasive biomarker for this disease.

Recent advances in molecular diagnosis of hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is a dominant autosomal genetic syndrome, accounting for 5%-10% of all colorectal cancers. It is caused by inactivating germ-line mutations of DNA mismatch repair (MMR) genes, including hMLH1, hMSH2, hMSH6, hPMS2, and hPMS1. HNPCC shows a tendency towards early age at onset, multiplicity of tumors, right-sided colon involvement, characteristic tumor pathology, and spectrum of extracolonic tumors. The diagnosis of HNPCC mainly relies on history and genetic linkage analysis. Patients meeting the Amsterdam criteria or Bethesda guidelines should undergo detection of microsatellite instability and immunohistochemistry analysis of hMSH2 and hMLH1 expression. If one of the two detections yields a positive result, molecular genetic testing for germline mutations of MMR genes should be taken into consideration.

Serum proteomic analysis of hereditary nonpolyposis colorectal cancer

AIM: To identify differentially expressed serum proteins between preoperative patients with hereditary nonpolyposis colorectal cancer (HNPCC) and those with sporadic colorectal cancer to find potential markers for the diagnosis of HNPCC.

METHODS: The composition of serum proteins was detected by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) and protein chip assay in 20 preoperative HNPCC patients and 25 patients with sporadic colorectal cancer. Discriminatory serum protein profiles were analyzed with the Biomarker Wizard software and Biomarker Pattern software.

RESULTS: Two proteins (m/z 7 516.68 Da and 4 827.07 Da) were chosen to create a decision classification tree model which could discriminate the two groups of patients. In the test mode, the accuracy, sensitivity, specificity, and positive predictive value of the model for prediction of HNPCC was 86.7%, 72.3%, 95.1% and 92.5%, respectively, while the corresponding values for blinded validation were 75.6%, 100%, 69.8% and 99.2%, respectively.

CONCLUSION: The classification tree model constructed with two differentially expressed proteins identified by SELDI-TOF-MS between HNPCC patients and patients with sporadic colorectal cancer possesses high sensitivity and specificity in the prediction of HNPCC.

Germline mutation analysis of hPMS2 gene in Chinese families with hereditary nonpolyposis colorectal cancer

AIM: To study the germline mutation of hPMS2 gene in 26 unrelated Chinese hereditary nonpolyposis colorectal cancer (HNPCC) probands and to fulfill the screening strategy for HNPCC in Chinese.

METHODS: Genomic DNA was extracted from the peripheral blood. To avoid the interference of pseudogene in detection of the remaining 11 exons (exon 1-5, 9, 11-15), long-range polymerase chain reaction (PCR) was conducted to amplify the complete coding region of hPMS2 gene firstly. Then 1/8 of the PCR products were used as template to amplify the individual exon respectively and DNA sequencing was done. Direct DNA sequencing of the conventional PCR products of exon 6, 7, 8 and 10 of hPMS2 gene was performed. The same analysis was made in 130 healthy persons without family histories of HNPCC to further investigate the pathological effects of the detected missense mutation.

RESULTS: One HNPCC proband fulfilled Bethesda guidelines and was found to carry the germline mutation of hPMS2 gene, which has not been reported in Chinese HNPCC families. It was a missense mutation at c.1532C>T of exon 11. It was detected in three controls as well with an occurrence rate of 2.3% (3/130). Since it could not be found in the PMS2-single nucleotide polymorphism (SNP) database, this missense mutation is a new SNP unreported up to date. Meanwhile, 260 reported SNPs of hPMS2 gene were detected in the 26 HNPCC probands. The 2nd and 5th exons were probably the hot SNP regions of hPMS2 gene in Chinese HNPCC families involving 53.1% of all reported SNP.

CONCLUSION: The germline mutation of hPMS2 gene may be rare in Chinese HNPCC families. The 2nd and 5th exons are hot SNP regions of hPMS2 gene.

Cyclooxgenase-2, β-catenin and matrix metalloproteinase-7 expression and their correlation with invasion/metastasis behaviours of hereditary nonpolyposis colorectal cancer

AIM: To detect cyclooxgenase-2 (COX-2), β-catenin (β-cat) and matrix metalloproteinase-7 (MMP-7) expression in hereditary nonpolyposis colorectal cancer (HNPCC) and sporadic colorectal carcinoma (CRC), and to analyze their relationship with the biological behaviour of HNPCC.

METHODS: The SP Immunohistochemical staining was used to detect COX-2, β-cat and MMP-7 protein expression in sample tissues of 28 HNPCC, 30 sporadic CRC and 10 normal colorectal cancer. All of the specimens were selected beforehand by hMSH2 and hMLH1 Immunohistochemical staining. And their corresponding clinical data were analyzed retrospectively.

RESULTS: The positive expression rates of COX-2, β-cat in cytoplasm and MMP-7 expression differed significantly between HNPCC and sporadic CRC (χ² = 14.8352, P = 0.0001; χ² = 5.6425, P = 0.0175; χ² = 10.6454, P = 0.0011). Positive rates of malposed β-cat and MMP-7 were closely correlated with the neoplastic invasive depth in HNPCC group and sporadic CRC group (P = 0.0127, P = 0.0001; P = 0.0227, P = 0.0261) and lymph node metastasis (P = 0.0000, P = 0.0001; P = 0.0227, P = 0.0261), but not with the sex, the size or position of the tumour. COX-2 expression was bound up with the neoplastic invasive depth (P = 0.0166) in HNPCC group, but not with the lymph node metastasis. However, in sporadic CRC group, COX-2 expression was related with neither neoplastic invasive depth nor lymph node metastasis. There was a stable positive relationship among COX-2, malposed β-cat and MMP-7 expression both in HNPCC and sporadic CRC (COX-2 and malposed β-cat: r = 0.417, P = 0.011, r = 0.504, P = 0.006; malposed β-cat and MMP-7: r = 0.396, P = 0.027, r = 0.429, P = 0.021; COX-2 and MMP-7: r = 0.315, P = 0.028, r = 0.429, P = 0.021).

CONCLUSION: The present study demonstrates that the COX-2, β-cat in cytoplasm and MMP-7 expression has marked difference among HNPCC, sporadic CRC and normal colorectal tissues. This may be an important reason why HNPCC tumors have a less invasive and metastatic potential compared with sporadic variants.

Diagnosis and treatment of Gardner syndrome with gastric polyposis: A case report and review of the literature

Gardner syndrome (GS) is an autosomal dominant disease characterized by the presence of colonic polyposis, osteoma and soft tissue tumors. It is regarded as a clinical subgroup of familial adenomatous polyposis (FAP) and may present at any age from 2 mo to 70 years with a variety of symptoms, either colonic or extracolonic. We present a case of a 23-year-old female patient with GS who presented with gastric polyposis and was successively treated with restorative proctocolectomy in combination with ileal pouch anal anastomosis (RPC/IPAA), ileostomy, ileostomy closure operation, snare polypectomy during 8 mo. After operation, the patient took oral traditional Chinese medicine pills made of Fructus mume and Bombyx batryticatu for about 6 mo. The innutrition and anaemia of this patient were gradually improved. Gastroscopy showed that the remnant gastric polypi gradually decreased and finally disappeared 19 mo after the first operation. The patient had 2-3 times of solid stool per day at the time we wrote this paper.

Surveillance colonoscopy practice in Lynch syndrome in the Netherlands: A nationwide survey

Lynch syndrome, or hereditary nonpolyposis colorectal cancer (HNPCC), is the most common genetic disorder predisposing to colorectal cancer. As regular colonoscopic surveillance has been shown to reduce the incidence of colorectal cancer, this strategy is recommended worldwide. Recently, several advances in colonoscopic techniques have improved detection rates of neoplasia in Lynch syndrome. In this nationwide survey, we evaluated current surveillance colonoscopy practices for Lynch syndrome in the Netherlands and the extent to which advanced techniques have been adopted in routine clinical practice.

Expression of transforming growth factor β receptor Type Ⅱ, matrix metalloproteinase-7 and tissue inhibitor of metalloproteinase-2 and their roles in the invasion and metastasis of hereditary nonpolyposis colorectal cancer

AIM: To investigate the roles of transforming growth factor β receptor Type Ⅱ (TβRⅡ), matrix metalloproteinase-7 (MMP-7) and tissue inhibitor of metalloproteinase-2 (TIMP-2) expression in the invasion and metastasis of human hereditary nonpolyposis colorectal cancer (HNPCC).

METHODS: Immunohistochemical staining was used to detect the expressions of TβRⅡ, MMP-7 and TIMP-2 protein in 30 cases of sporadic colorectal cancer (sporadic CRC) and 30 cases of HNPCC, and their corresponding clinical data were analyzed retrospectively.

RESULTS: The positive rates of TβRⅡ, MMP-7 and TIMP-2 expression in HNPCC were 40.0%, 46.7% and 63.3% respectively, while in sporadic CRC, the rates were 73.3%, 86.7% and 20.0% respectively. The ratio of MMP-7(+~++) to TIMP-2(-) in sporadic CRC was higher while that of MMP-7(-) to TIMP-2(+~++) was lower significantly than that in HNPCC. TβRⅡ, MMP-7 and TIMP-2 expression were closely related to the depth of invasion and lymph node metastasis, but not to the sex of patients, tumor size and position. The positive rate of MMP-7 expression was significantly increased in tissues with extra-chorion invasion and metastasis, but the expression of TβRⅡ and TIMP-2 were markedly decreased (P < 0.05). In HNPCC and sporadic CRC, positive correlation was found between TβRⅡ and MMP-7 expression (r = 0.735, P = 0.000; r = 0.792, P = 0.000), while negative correlation existed between TIMP-2 and TβRⅡ expression (r = -0.582, P = 0.001; r = -0.394, P = 0.031) as well as between TIMP-2 and MMP-7 expression (r = -0.473, P = 0.008; r = -0.388, P = 0.034).

CONCLUSION: TβRⅡ, MMP-7 and TIMP-2 are differently expressed in HNPCC and sporadic CRC. The expression rates and intensities of TβRⅡ and MMP-7 are obviously higher in sporadic CRC than those in HNPCC, while the positive expression of TIMP-2 was a reverse situation. So the imbalance of MMP-7/TIMP-2 is increased in sporadic CRC. Down-regulated expression of MMP-7, TβRⅡ and up-regulated expression of TIMP-2 may play important roles in the invasion and metastasis of HNPCC.

Role of detection of microsatellite instability in Chinese with hereditary nonpolyposis colorectal cancer or ordinary hereditary colorectal cancer

AIM: To detect microsatellite instability (MSI) in patients with hereditary nonpolyposis colorectal cancer or ordinary hereditary colorectal cancer and to provide criteria for screening the kindreds with hereditary nonpolyposis colorectal cancer at molecular level.

METHODS: MSI was detected in the specimens from 20 cases with HNPCC, 20 cases with ordinary hereditary colorectal cancer and 20 cases with sporadic colorectal cancer by means of polymerase chain reaction-single strand conformation polymorphism.

RESULTS: The positive rate of MSI was 85% (17/20) in HNPCC group, 40% (8/20) in ordinary hereditary colorectal cancer group and 10% (2/20) in the sporadic colorectal cancer group respectively. The differences were significant. The mean ages of the three groups were 43.6, 52.2, and 61.8 years respectively, which increased gradually. The incidence of right hemicolon cancer was 64.7%, 37.5%, and 0% respectively, which decreased gradually and had significant difference. The expression ratio of BAT26 and BAT25 was 94.1% respectively, which was highest in the 5 gene sites studied. The incidence of poorly differentiated adenocarcinoma was 70.6% in HNPCC group among high frequency microsatellite instability (MSI-H), which was higher than the other two groups, which had 50% and 50% respectively.

CONCLUSION: The incidence of MSI-H is higher in HNPCC group. The detection of MSI is simple and economical and has high correlation with the clinicopathologic feature of HNPCC and can be used as a screening method to detect the germ line mutation of the mismatch repair gene.

Multiple primary colorectal carcinomas: an analysis of 42 cases

AIM: To conclude the clinical characteristics of multiple primary colorectal carcinoma (MPCC).

METHODS: The clinical data of 42 patients with MPCC out of 1354 primary colorectal cancer cases, who were treated in our hospital from 1980 to 2005, were retrospectively analyzed.

RESULTS: The percentage of patients with MPCC was 3.10% (synchronous: 0.96%; metachronous: 2.14%). Of the 42 cases, 20 (1.48%) were accompanied by carcinoma of other organs. Adenocarcinoma was the most common cancer, locating at the right colon (46.3%) and rectum (31.3%). The tumors of other organs were mainly located at stomach, small intestine, breast, ovary and uterus. The data of 12 cases (12/42, 28.6%) were in accordance with Amsterdam criteria Ⅱ for hereditary nonpolyposis colorectal cancer (HNPCC), and the data of 16 cases (16/42, 37.2%) were in accordance with the Chinese criteria for HNPCC. Colon fiberscopy was helpful in the diagnosis of MPC.

CONCLUSION: MPCC, with a high incidence rate, has particular epidemic, clinical and pathological characteristics. Colon fiberscopy is important in the diagnosis of MPC, and postoperative following up should be strengthened for the diagnosis of HNPCC.

Clinical phenotype and prevalence of hereditary nonpolyposis colorectal cancer syndrome in Chinese population

AIM: To describe systematically the clinical characteristics and phenotype of HNPCC families and the prevalence of HNPCC in the general population of CRC patients in China.

METHODS: HNPCC kindreds and CRC patients were from two sources. One was that we consecutively investigated kindreds and patients by ourselves. And the other was the published Chinese and foreign literature related to Chinese HNPCC syndrome. There were 142 HNPCC families fulfilling AC I and/or AC II including 57 families with detailed data, and 3874 general primary CRC patients in all. All statistical tests were two-sided.

RESULTS: In AC I families, the number of Lynch syndrome I and II families were 25 (47.2%) and 28 (52.8%) respectively. There were 215 patients (82.4%) with CRC, 67 patients (25.7%) with extracolonic cancer and 50 patients (19.2%) with multiple primary cancers. In all CRC patients, multiple primary CRC were in 41 patients (19.1%), and the first-CRC was right-sided colorectal cancer in 143 patients (66.5%) and rectal cancer in 44 patients (20.5%). 8.8% and 19.2% of the first cancer were CRC and extracolonic cancers. Among those patients whose first cancer was CRC, 66.8% and 19.9% were right-sided colorectal cancer and rectal cancer, respectively. The similar results were found in AC II families. Normal distribution was only found in the distribution of the age of diagnosis of the first cancer in both AC I families (coefficient of skewness: u = 0.81, 0.20<0.40<P<0.50; coefficient of kurtosis: u = 1.13, 0.20<P<0.40, α = 0.20) and AC II families (coefficient of skewness: u = 0.63, P>0.5>0.20; coefficient of kurtosis: u = 0.84, 0.20<0.40<P<0.50, α = 0.20), but not found in the distribution of the age of diagnosis of the first CRC. When patients with HNPCC-associated cancer suffered from the first malignant tumor in HNPCC families diagnosed by AC I and AC II, the mean age and median age were 45.1±12.7 years and 44.0 years, 45.2±12.7 years and 44.5 years, respectively. The median age of diagnosis of the first tumor of the patients in the later generation was younger than that in the previous generation. Many extracolonic cancers were found to be associated with HNPCC syndrome. Gastric cancer was the most frequent extracolonic cancer followed by endometrial cancer and hepatocarcinoma. In general population of CRC patients, the prevalence of HNPCC diagnosed by AC I and AC II were 1.3% and 2.2%, respectively.

CONCLUSION: The clinical phenotype and prevalence of Chinese HNPCC syndrome are similar to those of Europeans and Americans. Gastric cancer is the most common extracolonic malignant tumor. The age of diagnosis of the first malignant tumor tends to be increasingly younger in patients with HNPCC-related tumors.