Lynch syndrome: the influence of environmental factors on extracolonic cancer risk in hMLH1 c.C1528T mutation carriers and their mutation-negative sisters

Impact of hormonal contraception on endometrial histology in patients with Lynch syndrome, a retrospective pilot study

Hormonal contraception (HC) is a well-recognized protection against endometrial cancer (EC) in the general population. It has not been established if this is also applicable to women with Lynch syndrome (LS), a condition associated with a up to 50% lifetime risk of developing EC. The objective of this study was to evaluate if the use of HC influences the incidence of endometrial hyperplasia and EC in women with LS by comparing the histology of annual endometrial biopsies obtained in patients with LS who are using HC versus non-users. This is a retrospective cohort study conducted with endometrial biopsies obtained in women 30 to 50 years of age with LS. The Pearson Chi-square test was performed to compare the prevalence of cancer and hyperplasia in the HC users and in the non-HC users groups. A total of 164 endometrial biopsies obtained among 75 women were suitable for analysis. Among the 86 biopsies obtained in the non-HC group, 81.4% (70/86) were normal. Two cases of endometrial carcinoma (2.3%) and 6 endometrial hyperplasia without atypia were found (7.0%). Among the 78 biopsies performed in patients using HC, 78.2% (61/78) were normal. Three endometrial hyperplasia without atypia (3.8%) and three cases of EC were diagnosed (3.8%). This study suggests that, in women of 30 to 50 years of age with LS, the use of hormonal contraception does not seem to decrease the occurrence of endometrial hyperplasia/carcinoma on annual endometrial histology.

Genetic insights: High germline variant rate in an indigenous African cohort with early-onset colorectal cancer

Introduction

The increase in incidence of colorectal cancer in young patients of African ancestry coupled with increased aggressiveness has warranted investigation of the heritable nature of these cancers. Only a limited number of published reports of hereditary colorectal cancer in indigenous African populations have been reported and no systematic screening of these groups has been performed previously. We aimed to investigate causative germline variants and to establish the incidence of pathogenic/likely pathogenic germline variants in the known colorectal cancer genes in indigenous African colorectal cancer patients using a next-generation sequencing (NGS) multigene panel.

Materials and methods

Patients were selected from two hospitals in Cape Town and Johannesburg, South Africa. Patients with unresolved molecular diagnosis with an age of onset below or at 60 years were selected. Germline DNA samples were analyzed using a 14-gene NGS panel on the Ion Torrent platform. Variant calling and annotation were performed, and variants were classified according to the American College of Medical Genetics and Genomics guidelines. Observed variants were verified by Sanger sequencing and/or long-range PCR.

Results

Out of 107 patients, 25 (23.4%) presented with a pathogenic/likely pathogenic germline variant (PGV). Fourteen PGVs in at least one mismatch repair (MMR) gene were identified and verified in 12 patients (11.2%). Of these MMR gene variants, five were novel. The remaining 10 PGVs were in the APC, BMPR1A, MUTYH, POLD1, and TP53 genes.

Conclusion

The high incidence of PGVs associated with early-onset colorectal cancer in indigenous African patients has important implications for hereditary colorectal cancer risk management. These findings pave the way for personalized genetic screening programs and cascade testing in South Africa. The next step would involve further screening of the unresolved cases using tools to detect copy number variation, methylation, and whole exome sequencing.

Variation in physician-directed immunohistochemistry screening among women with endometrial cancer

Objective

Immunohistochemistry screening is a reliable method for identifying women with endometrial cancer who are at risk for Lynch syndrome, but clinical workflows used to implement immunohistochemistry screening protocols can vary by institution. The goal of this study was to investigate variation in performance of immunohistochemistry screening when a physician order is required.

Methods

Retrospective study from an integrated healthcare system with a risk-based immunohistochemistry screening policy for Lynch syndrome from January 2015 to December 2016. Immunohistochemistry screening was indicated for all women with endometrial cancer aged <60 years and women with endometrial cancer aged ≥60 years who had a personal/family history suggestive of Lynch syndrome. However, a physician order was needed to have immunohistochemistry screening performed on the tumor specimen as our health system did not have reflex screening in the clinical workflow. Demographics and tumor characteristics were reviewed, and patients were stratified by immunohistochemistry screening status. Multivariable regression was performed to identify factors associated with immunohistochemistry performance and reported as odds ratios (ORs) with 95% confidence intervals (CIs).

Results

There were 1399 eligible patients in the study. With a required physician order, immunohistochemistry screening rates (20% overall, 34% aged <60 years) were significantly lower than previous reports (36% overall, 90% aged <60 years, p≤0.0001 for both comparisons). Significant factors associated with immunohistochemistry screening performance identified by multivariable analysis included age, race, body mass index, personal/family cancer history, diabetes, endometrioid histology, and tumor grade. Asian women were most likely to have immunohistochemistry screening (OR 1.58, 95% CI 1.07 to 2.34) whereas black women were least likely (OR 0.43, 95% CI 0.22 to 0.91).

Conclusions

Immunohistochemistry screening rates in women with endometrial cancer were lower in our health system compared with prior reports in the literature, and there were variations in screening performance according to patient age, race, and body mass index. Requiring a physician order for immunohistochemistry screening likely creates a barrier in screening uptake, therefore automated immunohistochemistry screening is recommended.

Association of Combined Estrogen-Progestogen and Progestogen-Only Contraceptives with the Development of Cancer

Combined estrogen-progestogen contraceptives (oral contraceptives or OCs) and progestogen-only contraceptives (POCs) are synthetic steroids that bind to steroid hormone receptors, which are widespread throughout the body. They have a profound effect on cellular physiology. Combined OCs have been classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens, but their findings have not been updated recently. In order to update the information and better understand the impact that OCs and POCs have on the risk of development of cancers, a comprehensive literature search was undertaken, focusing on more recently published papers. In agreement with the IARC, the recent literature confirms an increased risk of breast cancer and cervical cancer with the use of OCs. The recent literature also confirms the IARC conclusion that OCs decrease the risk of ovarian and endometrial cancers. However, there is little support from recent studies for the IARC conclusion that OCs decrease the risk of colorectal cancer or increase the risk of liver cancer. For liver cancer, this may be due to the recent studies having been performed in areas where hepatitis is endemic. In one large observational study, POCs also appear to increase the overall risk of developing cancer. OCs and POCs appear to increase the overall risk of cancer when carefully performed studies with the least intrinsic bias are considered.

Summary

OCs have been classified as cancer-causing agents, especially leading to increases in breast cancer and cervical cancer. A review of the recent scientific literature was performed to see whether this still appears to be the case. The recent literature supports the cancer-causing role of OCs especially for breast cancer and cervical cancer. Studies also indicate that progesterone-only contraceptives (such as implants and vaginal rings) also can cause cancer. This is especially true for breast cancer and cervical cancer.

Comparison of lifestyle, hormonal and medical factors in women with sporadic and Lynch syndrome-associated endometrial cancer: A retrospective case-case study

Data available on lifestyle-associated hormonal and medical factors among endometrial cancer (EC)-affected women who carry the Lynch Syndrome (LS) mutation is limited. The aim of the present retrospective case study was to compare the reproductive and medical history, as well as lifestyle-associated factors, among patients with LS and sporadic EC. The study population consisted of 50 verified germline mismatch repair (MMR) gene mutation carriers diagnosed with EC, and 110 sporadic EC patients. Data were collected using postal questionnaires. Apart from the mean age at the time of the EC diagnosis (LS, 48.7 years compared with sporadic patients, 55.2 years; P<0.0001), the characteristics of sporadic and LS EC patients were similar with regard to body mass index (BMI) at age 18, 40 or at the time of the survey, and smoking and alcohol consumption. LS women reported a significantly lower rate of spontaneous abortion (P=0.043) and also more frequent use of contraceptives (P=0.004). The prevalence of co-morbidities, including diabetes, atherosclerosis, hypercholesterolemia and hypertension, was similar between the LS and the sporadic groups. A trend for a higher prevalence of endometriosis among mutation carriers was detected (16.0 vs. 8.1%, P=0.137). As anticipated, the prevalence of gastrointestinal tract, urinary tract and ovarian cancer was higher among the LS women (P<0.0001, P=0.006 and P=0.056, respectively). Co-morbidity and lifestyle-associated factors appeared to be comparable among patients with LS and sporadic EC. The reported difference in the use of contraceptives warrants further investigation. Future studies are also required to address the possible association between LS and endometriosis.

Ethnicity and Prostate Cancer in Southern Nigeria: A Preliminary Report

Introduction:

The natural history of prostate cancer varies among patients. The aim of this study is to detect any variations in clinical and pathological characteristics of the tumor in patients from different ethnic groups in Southern Nigeria.

Patients and Methods:

Consecutive patients who presented with features of prostatic diseases at the Urology Units of University of Port Harcourt Teaching Hospital, Port Harcourt and Nnamdi Azikiwe University Teaching Hospital, Nnewi, were evaluated prospectively with history, physical examination, and relevant investigations using a proforma. Data obtained were collated and analyzed statistically using the Chi-square test and Microsoft Excel.

Results:

Of 187 patients studied, 169 were analyzed. Eighty-six were Ibos, 31 Ijaws, 25 Ikwerres, and 12 Ogonis. Two were from each Etche, Urhobo, Opobo, and Effik; 4 from Andoni, and 3 Ibibio. Fifty-seven (66.3%) Ibos presented with the disease at higher ages (70–80 years) than 19 (61.3%) Ijaws and 11 (91.7%) Ogonis. These age differences were statistically significant with 95% and 99.9% confidence, respectively. All cases were adenocarcinomas. Clinical features, pattern of serum prostate-specific antigen levels, grades of the tumors, tumor metastases, and complications were similar for all ethnic groups. Although more Ibos had tumors with relatively more aggressive metastatic features, there was no statistical significance.

Conclusion:

Clinical and pathological features of adenocarcinoma of the prostate in Ibos, Ikwerres, Ijaws, and Ogonis were found to be similar. However, Ibos presented with the disease at older ages than Ijaws and Ogonis.

Female Hormonal Factors and the Risk of Endometrial Cancer in Lynch Syndrome

IMPORTANCE

Apart from hysterectomy, there is no consensus recommendation for reducing endometrial cancer risk for women with a mismatch repair gene mutation (Lynch syndrome).

OBJECTIVE

To investigate the association between hormonal factors and endometrial cancer risk in Lynch syndrome.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study included 1128 women with a mismatch repair gene mutation identified from the Colon Cancer Family Registry. Data were analyzed with a weighted cohort approach. Participants were recruited between 1997 and 2012 from centers across the United States, Australia, Canada, and New Zealand.

EXPOSURES

Age at menarche, first and last live birth, and menopause; number of live births; hormonal contraceptive use; and postmenopausal hormone use.

MAIN OUTCOMES AND MEASURES

Self-reported diagnosis of endometrial cancer.

RESULTS

Endometrial cancer was diagnosed in 133 women (incidence rate per 100 person-years, 0.29; 95% CI, 0.24 to 0.34). Endometrial cancer was diagnosed in 11% (n = 70) of women with age at menarche greater than or equal to 13 years compared with 12.6% (n = 57) of women with age at menarche less than 13 years (incidence rate per 100 person-years, 0.27 vs 0.31; rate difference, -0.04 [95% CI, -0.15 to 0.05]; hazard ratio per year, 0.85 [95% CI, 0.73 to 0.99]; P = .04). Endometrial cancer was diagnosed in 10.8% (n = 88) of parous women compared with 14.4% (n = 40) of nulliparous women (incidence rate per 100 person-years, 0.25 vs 0.43; rate difference, -0.18 [95% CI, -0.32 to -0.04]; hazard ratio, 0.21 [95% CI, 0.10 to 0.42]; P < .001). Endometrial cancer was diagnosed in 8.7% (n = 70) of women who used hormonal contraceptives greater than or equal to 1 year compared with 19.2% (n = 57) of women who used contraceptives less than 1 year (incidence rate per 100 person-years, 0.22 vs 0.45; rate difference, -0.23 [95% CI, -0.36 to -0.11]; hazard ratio, 0.39 [95% CI, 0.23 to 0.64]; P < .001). There was no statistically significant association between endometrial cancer and age at first and last live birth, age at menopause, and postmenopausal hormone use.

CONCLUSIONS AND RELEVANCE

For women with a mismatch repair gene mutation, some endogenous and exogenous hormonal factors were associated with a lower risk of endometrial cancer. These directions and strengths of associations were similar to those for the general population. If replicated, these findings suggest that women with a mismatch repair gene mutation may be counseled like the general population in regard to hormonal influences on endometrial cancer risk.

Clinical significance of mismatch repair gene expression in sporadic colorectal cancer

Mismatch repair (MMR) genes play an important role in the occurrence and development of sporadic colorectal cancer; however, the effect of MMR genes on clinicopathological features and prognosis remains unclear. The aim of the present study was to observe the clinical significance of MMR gene expression in sporadic colorectal cancer. Clinicopathological data and postoperative samples from 404 patients with sporadic colorectal cancer were obtained from the Affiliated Tumor Hospital of Xinjiang Medical University. The immunohistochemistry PV-9000 two-step method was performed to measure the protein expression of human mutL homolog 1 (hMLH1), human mutS homolog (hMSH) 2, human postmeiotic segregation increased 2 (hPSM2) and hMSH6. Differences in clinicopathological features, family history and survival time subsequent to surgery between groups with normal and aberrant MMR protein (MMRP) expression were compared. A total of 27.23% of all patients showed aberrant nuclear staining of MMRP. Among the patients with aberrant MMRP expression, a higher proportion of patients showed aberrant expression of more than one type of MMRP than aberrant expression of only one type of MMRP. Aberrant expression of hMLH1/hPSM2 was most commonly observed (29/404). In addition, aberrant MMRP expression in colorectal cancer was indicated predominantly in the right hemicolon. Histological type primarily showed mucinous adenocarcinoma. In addition, with increasing body mass index (BMI), the MMRP deficiency rate was also shown to increase gradually. There was a close association between MMRP expression deficiency and family history of cancer (P<0.05). For TNM stage III patients, the Kaplan-Meier survival curve showed that the aberrant MMRP expression group had a three-year disease-free survival (DFS) rate of 66.67%, which was longer than the DFS rate of the normal group (55.41%), with no statistical difference (P>0.05). In conclusion, the immunohistochemistry PV-9000 two-step method can be used to measure MMRP expression in colorectal cancer. Aberrant MMRP expression is closely correlated with tumor location, histological type, BMI and tumor family history in sporadic colorectal cancer. Aberrant MMRP expression may have an effect on the prognosis of stage III patients.

Excess of extracolonic non-endometrial multiple primary cancers in MSH2 germline mutation carriers over MLH1

BACKGROUND

The lynch syndrome (LS) tumor spectrum involves colorectal cancer (CRC), endometrial cancer (EC), and less frequently various extracolonic non-endometrial cancers (non-EC). The organ-specific survival rates of these patients are well defined, however, the collective survival of all-cancers combined (CRC + EC + non-EC) are unclear.

METHODS

Fifty-two MSH2 patients and 68 MLH1 patients were followed for a median of 6.3 years after diagnosis of first cancer, regardless of type. The proportions of CRC only, EC, non-EC, and multiple primary cancers were compared between the two genotypes. Kaplan-Meier curves were developed for survival comparisons.

RESULTS

MSH2 patients present less frequently with only CRC (37% MSH2, 62% MLH1, P = 0.0096), manifest more multiple primary cancers (38% MSH2, 18% MLH1, P = 0.013), develop more extracolonic cancers (62% MSH2, 38% MLH1, P = 0.003), non-EC only cancers (46% MSH2, 24% MLH1, P = 0.028) and carry a greater risk for urinary tract cancer (UTC) (13.4% MSH2, 1.5% MLH1, P = 0.024). There was no difference in 10-year survival between the two groups (P = 0.4).

CONCLUSION

The additional propensity for UTC in MSH2 carriers argues in favor of UTC screening in MSH2 individuals. Other types of cancer screening should be tailored to the expression history of the specific LS mutation.

Cell cycle-related genes as modifiers of age of onset of colorectal cancer in Lynch syndrome: a large-scale study in non-Hispanic white patients

Heterogeneity in age of onset of colorectal cancer in individuals with mutations in DNA mismatch repair genes (Lynch syndrome) suggests the influence of other lifestyle and genetic modifiers. We hypothesized that genes regulating the cell cycle influence the observed heterogeneity as cell cycle-related genes respond to DNA damage by arresting the cell cycle to provide time for repair and induce transcription of genes that facilitate repair. We examined the association of 1456 single nucleotide polymorphisms (SNPs) in 128 cell cycle-related genes and 31 DNA repair-related genes in 485 non-Hispanic white participants with Lynch syndrome to determine whether there are SNPs associated with age of onset of colorectal cancer. Genotyping was performed on an Illumina GoldenGate platform, and data were analyzed using Kaplan-Meier survival analysis, Cox regression analysis and classification and regression tree (CART) methods. Ten SNPs were independently significant in a multivariable Cox proportional hazards regression model after correcting for multiple comparisons (P < 5 × 10(-4)). Furthermore, risk modeling using CART analysis defined combinations of genotypes for these SNPs with which subjects could be classified into low-risk, moderate-risk and high-risk groups that had median ages of colorectal cancer onset of 63, 50 and 42 years, respectively. The age-associated risk of colorectal cancer in the high-risk group was more than four times the risk in the low-risk group (hazard ratio = 4.67, 95% CI = 3.16-6.92). The additional genetic markers identified may help in refining risk groups for more tailored screening and follow-up of non-Hispanic white patients with Lynch syndrome.

Correlation between body mass index and prevalence of hereditary nonpolyposis colorectal cancer in Korean patients with endometrial cancer

OBJECTIVE

The purpose of the study was to investigate the relationship between body mass index (BMI) and hereditary nonpolyposis colorectal cancer (HNPCC) in Korean women with endometrial cancer.

METHODS

Among 227 patients with endometrial cancer in the study population, 20 patients (8.8%) had HNPCC. The patients were divided into 2 groups based on the BMI: nonobese (BMI ≤25 kg/m) and obese (BMI >25 kg/m); then the nonobese group was subdivided into 2 groups: normal weight (BMI <23 kg/m) and overweight (BMI, 23-25 kg/m). The distributions of BMI categories were compared between patients with sporadic endometrial cancer and with HNPCC-related endometrial cancer.

RESULTS

Among 207 patients with sporadic endometrial cancer, 119 (57.5%) were nonobese and 88 patients (42.5%) were obese. Of 20 patients with endometrial cancer related to HNPCC, 10 (50.0%) were nonobese and 10 (50.0%) were obese. In a subgroup analysis of only nonobese patients, 68 patients with sporadic endometrial cancer had normal weight and 51 were overweight. On the other hand, all 10 patients with HNPCC related to endometrial cancer had normal weight. There was no significant difference between the group with HNPCC-related endometrial cancer and the group with sporadic endometrial cancer according to BMI (P = 0.221). However, BMI proportions in HNPCC related to endometrial cancer were significantly different from those in sporadic endometrial cancer (P = 0.016). Among a subgroup of nonobese patients, the proportion of normal weight was significant higher in patients with HNPCC-related endometrial cancer compared to those in sporadic endometrial cancer (P = 0.006).

CONCLUSION

Body mass index was not different between sporadic endometrial cancer and HNPCC-related endometrial cancer in Koreans. However, BMI proportions in the patients with HNPCC related to endometrial cancer was significantly different from those in sporadic endometrial cancer. Specifically, among nonobese patients, the proportion of normal weight was significantly high in Korean women with HNPCC.