Bone histomorphometry in transiliac biopsies from 48 normal, healthy men.

Investigators and clinicians use bone histomorphometry data from iliac bone biopsies to study bone abnormalities in diseased patients, and to understand the safety and effectiveness of pharmaceutical interventions. This requires access to a high quality normal data-set to be used for comparisons, a resource that has not been adequate to date. The objective of this work is to present static and dynamic bone histomorphometry data from transilial bone biopsies performed on 48 healthy males, evenly distributed between ages 45 and 75. In addition, we compared these results with results from our earlier study in normal postmenopausal women (Recker et al., 1988 [1]). The data include bone density and anthropometric measurements, micro-CT, and a collection of serum biochemical measurements. We found that several of the histomorphometry variables were correlated with serum measurements, i.e. serum testosterone and sex hormone-binding globulin (SHBG). Micro-CT variables were correlated with the static histomorphometry variables, and were very similar. Age-related changes were observed for both histomorphometry and Micro-CT, but were surprisingly small in most cases. Comparisons with our previously reported histomorphometry data from normal women were surprisingly similar, but there was a significant age by gender interaction in the wall thickness (W.Th) measurements, i.e. there was a small increase in this variable with age in men, and a significant decline with age in women. The population selected for this study, and the prior study in normal women, were carefully chosen so as to rule out the presence of clinical, life-style or other confounding factors. While the cohort chosen herein was a convenience sample, and not a population-based sample, we believe it can be used as a reference standard with proper precautions in its interpretation and in its comparisons with diseased populations.

Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial.

Importance: Evidence suggests that low vitamin D status may increase the risk of cancer. Objective: To determine if dietary supplementation with vitamin D3 and calcium reduces the risk of cancer among older women. Design, Setting, and Participants: A 4-year, double-blind, placebo-controlled, population-based randomized clinical trial in 31 rural counties (June 24, 2009, to August 26, 2015-the final date of follow-up). A total of 2303 healthy postmenopausal women 55 years or older were randomized, 1156 to the treatment group and 1147 to the placebo group. Duration of treatment was 4 years. Interventions: The treatment group (vitamin D3 + calcium group) received 2000 IU/d of vitamin D3 and 1500 mg/d of calcium; the placebo group received identical placebos. Main Outcomes and Measures: The primary outcome was the incidence of all-type cancer (excluding nonmelanoma skin cancers), which was evaluated using Kaplan-Meier survival analysis and proportional hazards modeling. Results: Among 2303 randomized women (mean age, 65.2 years [SD, 7.0]; mean baseline serum 25-hydroxyvitamin D level, 32.8 ng/mL [SD, 10.5]), 2064 (90%) completed the study. At year 1, serum 25-hydroxyvitamin D levels were 43.9 ng/mL in the vitamin D3 + calcium group and 31.6 ng/mL in the placebo group. A new diagnosis of cancer was confirmed in 109 participants, 45 (3.89%) in the vitamin D3 + calcium group and 64 (5.58%) in the placebo group (difference, 1.69% [95% CI, -0.06% to 3.46%]; P = .06). Kaplan-Meier incidence over 4 years was 0.042 (95% CI, 0.032 to 0.056) in the vitamin D3 + calcium group and 0.060 (95% CI, 0.048 to 0.076) in the placebo group; P = .06. In unadjusted Cox proportional hazards regression, the hazard ratio was 0.70 (95% CI, 0.47 to 1.02). Adverse events potentially related to the study included renal calculi (16 participants in the vitamin D3 + calcium group and 10 in the placebo group), and elevated serum calcium levels (6 in the vitamin D3 + calcium group and 2 in the placebo group). Conclusions and Relevance: Among healthy postmenopausal older women with a mean baseline serum 25-hydroxyvitamin D level of 32.8 ng/mL, supplementation with vitamin D3 and calcium compared with placebo did not result in a significantly lower risk of all-type cancer at 4 years. Further research is necessary to assess the possible role of vitamin D in cancer prevention. Trial Registration: clinicaltrials.gov Identifier: NCT01052051.

Aspirin use is associated with lower prostate cancer risk in male carriers of BRCA mutations.

Previous studies have shown that male BRCA mutation carriers stand at increased risk of developing prostate cancer and have concerns about developing cancer. Genetic counseling practitioners often discuss strategies for reducing the risk of cancer for patients at high risk due to their genetic background. Addressing modifiable health habits is one such strategy. Unfortunately, modifiable risk factors for prostate cancer have only been documented in the general population and have not yet been studied in the BRCA carrier subpopulation. Therefore, this study aimed to identify modifiable risk factors for prostate cancer in BRCA carriers. We examined prostate cancer risk factors in 74 men who were part of families with a BRCA mutation. This study examined nine dichotomous variables including: exercise, history of vasectomy, smoking history, alcohol use, finasteride use, statin use, aspirin use, coffee use, and vitamin use. The survey was sent to all cases of prostate cancer in the Hereditary Cancer Center Database at Creighton University with a known BRCA status. This study confirmed the protective benefits of daily aspirin use, which have been observed in previous studies of the general population, and suggests its benefit in BRCA carriers. Protective benefits from regular vigorous exercise and daily coffee use trended towards significance, but neither factor withstood the Bonferroni Correction for multiple comparisons.

Role for the epidermal growth factor receptor in chemotherapy-induced alopecia.

Treatment of cancer patients with chemotherapeutics like cyclophosphamide often causes alopecia as a result of premature and aberrant catagen. Because the epidermal growth factor receptor (EGFR) signals anagen hair follicles to enter catagen, we hypothesized that EGFR signaling may be involved in cyclophosphamide-induced alopecia. To test this hypothesis, skin-targeted Egfr mutant mice were generated by crossing floxed Egfr and Keratin 14 promoter-driven Cre recombinase mice. Cyclophosphamide treatment of control mice resulted in alopecia while Egfr mutant skin was resistant to cyclophosphamide-induced alopecia. Egfr mutant skin entered catagen normally, as indicated by dermal papilla condensation and decreased follicular proliferation, but did not progress to telogen as did Egfr wild type follicles. Egfr mutant follicles responded with less proliferation, apoptosis, and fewer p53-positive cells after cyclophosphamide. Treatment of control mice with the EGFR inhibitors erlotinib or gefitinib similarly suppressed alopecia and catagen progression by cyclophosphamide. Secondary analysis of clinical trials utilizing EGFR-targeted therapies and alopecia-inducing chemotherapy also revealed evidence for involvement of EGFR in chemotherapy-induced alopecia. Taken together, our results demonstrated the involvement of EGFR signaling in chemotherapy-induced alopecia, which will help in the design of novel therapeutic regimens to minimize chemotherapy-induced alopecia.

Phenotypic heterogeneity of hereditary gynecologic cancers: a report from the Creighton hereditary cancer registry.

To determine the validity of observations suggesting a significant dichotomy of gynecologic cancers determined by linkage to specific genetic defects associated with two major autosomal dominant hereditary cancer syndromes; the Creighton University Hereditary Cancer Registry was searched for female carriers of germ line mutations in BRCA1 and BRCA2, associated with the Hereditary Breast Ovarian Cancer syndrome, and in the mismatch repair (MMR) genes MLH1, MSH2 and MSH6, associated with Lynch syndrome, who were registered with invasive uterine, ovarian, fallopian tube or peritoneal cancers between January 1, 1959 and December 31, 2010. From 217 such cases, a total of 174 subjects, consisting of 95 BRCA1 and BRCA2 mutation carriers and 79 carriers of mutations in MMR genes, were identified who had current signed Health Insurance Portability and Accountability Act forms and complete primary diagnostic pathology reports and clinical records. Data meticulously extracted from these cases were categorized and statistically analyzed. There were highly significant differences between carriers of BRCA1 and BRCA2 mutations and carriers of MMR gene mutations in the proportion of serous carcinomas compared with endometrioid carcinomas of the uterus, including cervix and endometium (p < 0.002), ovaries (p < 0.001) and overall, including fallopian tube and peritoneum cancers (p < 0.001). Endometrioid carcinoma was found in one and transitional carcinoma in another of the 14 BRCA1 mutation carriers with fallopian tube cancer, and endometrioid carcinoma was found in two of four MMR gene mutation carriers with fallopian tube cancers. All other fallopian tube cancers were serous carcinomas. Seven BRCA1 and one BRCA2 mutation carriers were diagnosed with primary peritoneal serous carcinoma; no peritoneal carcinomas were registered in MMR gene mutation carriers. Nine of 14 gynecologic cancers with associated endometriosis in mutation carriers were endometrioid or endometrioid mixed carcinomas compared with just three of other histologic types. Primary breast cancers, that characterize the HBOC syndrome, were much more frequent in BRCA1 and BRCA2 mutation carriers; while multiple gynecologic cancers and associated colorectal and urinary tract cancers, which are features of Lynch syndrome, were more common in MMR gene mutation carriers. Both serous and endometrioid carcinomas were diagnosed in MMR gene mutation carriers at significantly younger ages than in BRCA1 and BRCA2 mutation carriers (p < 0.0006). These findings confirm a clear dichotomy of uterine, ovarian and fallopian tube cancers associated with inheritance of mutations in BRCA1 and BRCA2 contrasted with inheritance of MMR gene mutations. This opens possibilities for new approaches to molecular genetic research into carcinogenic pathways and raises important new considerations regarding counseling, screening, prophylaxis and treatment of mutation carriers.

Prevalence of extra-esophageal cancers in patients with Barrett's esophagus and esophageal adenocarcinoma.

BACKGROUND AND AIM: To compare the prevalence of extra-esophageal cancers in patients diagnosed with Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) with SEER database. METHODS: Patients with BE and EAC are part of a NIH supported Familial Barrett's investigation involving personal and family history and pathology correlation recorded in the database. Data pertaining to extra-esophageal cancers in the proband was extracted into an excel datasheet for analysis. Expected prevalence obtained from SEER (Surveillance, Epidemiology and End Results) NIH database (1973-2006) for the general population, matched for age, was compared with our cohort. Chi-square test was used for statistical analysis. RESULTS: There were 1091 probands in the database of whom 876 had complete personal history. The mean age was 57.6 (5-84 years) with 807 Caucasians and 710 males. Overall incidence of extra-esophageal cancers was higher in our cohort when compared with the general population. CONCLUSION: There is a strong association of certain cancer types in patients with BE and EAC. However, further epidemiologic and genetic research is needed for investigation and development of genetic fingerprints.

Comparison of extended colectomy and limited resection in patients with Lynch syndrome.

PURPOSE: The purpose of the study was to determine the advantages and disadvantages of prophylactic/extended colectomy (subtotal colectomy) in patients with Lynch syndrome who manifest colorectal cancer. METHODS: A retrospective cohort using Creighton University's hereditary cancer database was used to identify cases and controls. Cases are patients who underwent subtotal colectomy, either with no colorectal cancer diagnosis (prophylactic) or at diagnosis of first colorectal cancer; controls for these 2 types of cases were, respectively, patients who underwent no colon surgery or those having limited resection at time of diagnosis of first colorectal cancer. The Kaplan-Meier and proportional hazard regression models from the Statistical Analysis Software program was used to calculate the difference in survival, time to subsequent colorectal cancer, and subsequent abdominal surgery between cases and controls. RESULTS: The event-free survival of our study did not reach 50%, so we used the event-free survival at 5 years as our parameter to compare the 2 groups. The event-free survival for subsequent colorectal cancer, subsequent abdominal surgery, and death was 94%, 84%, and 93%, respectively, for cases and 74%, 63%, and 88%, respectively, for controls. Times to subsequent colorectal cancer and subsequent abdominal surgery were significantly shorter in the control group (P < .006 and P < .04, respectively). No significant difference was identified with respect to survival time between the cases and controls. CONCLUSIONS: Even though no survival benefit was identified between the cases and controls the increased incidence of metachronous colorectal cancer and increased abdominal surgeries among controls warrant the recommendation of subtotal colectomy in patients with Lynch syndrome.

Detecting BRCA2 protein truncation in tissue biopsies to identify breast cancers that arise in BRCA2 gene mutation carriers.

PURPOSE: Mutations in the BRCA2 gene are dominantly inherited but cause cancers when the wild-type allele has loss of heterozygosity (LOH) within the cancer. Because most disease-associated BRCA2 mutations are protein-truncating mutations, a test for truncated BRCA2 proteins should identify most BRCA2 hereditary cancers. METHODS: We have developed a tissue truncation test to identify truncated BRCA2 proteins in breast cancer tissue biopsies in vivo that does not use amplification or genetic manipulations. N-terminal and C-terminal antibodies are used to visualize protein truncation by demonstrating that the beginning of the protein is present but the end (ie, terminus) is absent. RESULTS: A quantitative C-terminal immunostaining score or a C-terminal to N-terminal truncation ratio correctly classified 20 of 21 breast cancers arising in BRCA2 mutation carriers and 57 of 58 cancers arising outside the context of a multiple-case breast cancer family. This represents a sensitivity of 95% and a specificity of 98%. Because of the presence of C-terminal BRCA2 protein and atypical clinical features of the misclassified cancer in a BRCA2 mutation carrier, we performed polymerase chain reaction and sequence analyses on this cancer. The results showed continued presence of the BRCA2 wild-type allele in the cancer, which indicated that intact BRCA2 protein was present in this cancer. CONCLUSION: This immunohistochemistry-based test (which takes only 4 hours) appears to identify BRCA2 hereditary cancer with high accuracy. The test also appears to diagnose the biochemical loss of BRCA2 protein in cancers (ie, BRCA2-mutant genotype), which will usually but not always agree with the presence of a germline BRCA2 mutation found by susceptibility testing by DNA sequencing of blood samples.

Association between rectal optical signatures and colonic neoplasia: potential applications for screening.

Field carcinogenesis detection represents a promising means for colorectal cancer (CRC) screening, although current techniques (e.g., flexible sigmoidoscopy) lack the requisite sensitivity. The novel optical technology low-coherence enhanced backscattering (LEBS) spectroscopy, allows identification of microscale architectural consequences of the field carcinogenesis in preclinical CRC models with unprecedented accuracy. To investigate the potential clinical translatability of this approach, we obtained biopsies from the normal-appearing rectal mucosa from patients undergoing colonoscopy (n = 219). LEBS signals were recorded through a bench-top instrument. Four parameters characterizing LEBS signal were linearly combined into a single marker. We found that LEBS signal parameters generally mirrored neoplasia progression from patients with no neoplasia, to 5 to 9 mm adenoma and to advanced adenomas. The composite LEBS marker calculated from the LEBS signal paralleled this risk status (ANOVA P < 0.001). Moreover, this was independent of CRC risk factors, benign colonic findings, or clinically unimportant lesions (diminutive adenomas, hyperplastic polyps). For advanced adenomas, the LEBS marker had a sensitivity of 100%, specificity of 80%, and area under the receiver operator characteristic curve of 0.895. Leave-one-out cross-validation and an independent data set (n = 51) supported the robustness of these findings. In conclusion, we provide the first demonstration that LEBS-detectable alterations in the endoscopically normal rectum were associated with the presence of neoplasia located elsewhere in the colon. This study provides the proof of concept that rectal LEBS analysis may potentially provide a minimally intrusive CRC screening technique. Further studies with an endoscopically compatible fiber optic probe are under way for multicenter clinical validation.

Lymphocyte recruitment into the tumor site is altered in patients with MSI-H colon cancer.

The ability of the host to mount an appropriate immune response to aberrant cells is one factor that determines prognosis in cancer patients. Naturally occurring regulatory T cells (T regs; CD4+ CD25+ cells) are key regulators of peripheral tolerance. It has been suggested that high levels of T regs are detrimental to the patient in some forms of cancer, but the role of these antigen-specific cells in individuals with colorectal cancers with high levels of microsatellite instability is unknown. Herein, we examined the ability of individuals with MSI-H or microsatellite stable colon cancer to recruit lymphocytes to the tumor site. Immunohistochemical staining was performed on archived paraffin-embedded specimens from a total of 38 individuals with MSI-H (n = 25) or MSS (n = 13) colon cancers to determine the proportion of CD3+, CD8+ and CD25+ cells infiltrating the tumor site. Patients with MSI-H colon cancers had increased percentages of CD8+ TILs (cytotoxic T cells) as compared to individuals with MSS colon cancer (47.3 vs. 24.04% of the infiltrate CD8+, respectively). No differences in the levels of CD25+ T cells were observed between individuals with MSI-H colon cancers and MSS colon cancers (0.53 vs. 0.54% CD25+, respectively). Together, these data suggest that the survival advantage enjoyed by patients with MSI-H colorectal cancer may, in part, be attributed to the increased cytolytic response, but not to an antigen-specific immunosuppressive response in MSS patients.

Familial myeloma.

We describe a family with five cases of multiple myeloma, three cases of monoclonal gammopathy of undetermined significance (MGUS), and five cases of prostate cancer in two generations. The putative progenitor had progeny with two female partners. The progeny had prostate cancer, multiple myeloma, and MGUS.

Understanding the development of human bladder cancer by using a whole-organ genomic mapping strategy.

The search for the genomic sequences involved in human cancers can be greatly facilitated by maps of genomic imbalances identifying the involved chromosomal regions, particularly those that participate in the development of occult preneoplastic conditions that progress to clinically aggressive invasive cancer. The integration of such regions with human genome sequence variation may provide valuable clues about their overall structure and gene content. By extension, such knowledge may help us understand the underlying genetic components involved in the initiation and progression of these cancers. We describe the development of a genome-wide map of human bladder cancer that tracks its progression from in situ precursor conditions to invasive disease. Testing for allelic losses using a genome-wide panel of 787 microsatellite markers was performed on multiple DNA samples, extracted from the entire mucosal surface of the bladder and corresponding to normal urothelium, in situ preneoplastic lesions, and invasive carcinoma. Using this approach, we matched the clonal allelic losses in distinct chromosomal regions to specific phases of bladder neoplasia and produced a detailed genetic map of bladder cancer development. These analyses revealed three major waves of genetic changes associated with growth advantages of successive clones and reflecting a stepwise conversion of normal urothelial cells into cancer cells. The genetic changes map to six regions at 3q22-q24, 5q22-q31, 9q21-q22, 10q26, 13q14, and 17p13, which may represent critical hits driving the development of bladder cancer. Finally, we performed high-resolution mapping using single nucleotide polymorphism markers within one region on chromosome 13q14, containing the model tumor suppressor gene RB1, and defined a minimal deleted region associated with clonal expansion of in situ neoplasia. These analyses provided new insights on the involvement of several non-coding sequences mapping to the region and identified novel target genes, termed forerunner (FR) genes, involved in early phases of cancer development.

Accurate classification of MLH1/MSH2 missense variants with multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR).

Lynch syndrome, also known as hereditary nonpolyposis colon cancer (HNPCC), is the most common known genetic syndrome for colorectal cancer (CRC). MLH1/MSH2 mutations underlie approximately 90% of Lynch syndrome families. A total of 24% of these mutations are missense. Interpreting missense variation is extremely challenging. We have therefore developed multivariate analysis of protein polymorphisms-mismatch repair (MAPP-MMR), a bioinformatic algorithm that effectively classifies MLH1/MSH2 deleterious and neutral missense variants. We compiled a large database (n>300) of MLH1/MSH2 missense variants with associated clinical and molecular characteristics. We divided this database into nonoverlapping training and validation sets and tested MAPP-MMR. MAPP-MMR significantly outperformed other missense variant classification algorithms (sensitivity, 94%; specificity, 96%; positive predictive value [PPV] 98%; negative predictive value [NPV], 89%), such as SIFT and PolyPhen. MAPP-MMR is an effective bioinformatic tool for missense variant interpretation that accurately distinguishes MLH1/MSH2 deleterious variants from neutral variants.

The risk of extra-colonic, extra-endometrial cancer in the Lynch syndrome.

Persons with the Lynch syndrome (LS) are at high risk for cancer, including cancers of the small bowel, stomach, upper urologic tract (renal pelvis and ureter), ovary, biliary tract and brain tumors, in addition to the more commonly observed colorectal and endometrial cancers. Cancer prevention strategies for these less common cancers require accurate, age-specific risk estimation. We pooled data from 4 LS research centers in a retrospective cohort study, to produce absolute incidence estimates for these cancer types, and to evaluate several potential risk modifiers. After elimination of 135 persons missing crucial information, cohort included 6,041 members of 261 families with LS-associated MLH1 or MSH2 mutations. All were either mutation carriers by test, probable mutation carriers (endometrial/colorectal cancer-affected), or first-degree relatives of these. Among mutation carriers and probable carriers, urologic tract cancer (N = 98) had an overall lifetime risk (to age 70) of 8.4% (95% CI: 6.6-10.8); risks were higher in males (p < 0.02) and members of MSH2 families (p < 0.0001). Ovarian cancer (N = 72) had an lifetime risk of 6.7% (95% CI: 5.3-9.1); risks were higher in women born after the median year of birth (p < 0.008) and in members of MSH2 families (p < 0.006). Brain tumors and cancers of the small bowel, stomach, breast and biliary tract were less common. Urologic tract cancer and ovarian cancer occur frequently enough in some LS subgroups to justify trials to evaluate promising prevention interventions. Other cancer types studied occur too infrequently to justify strenuous cancer control interventions.

Downregulation of death-associated protein kinase 1 (DAPK1) in chronic lymphocytic leukemia.

The heritability of B cell chronic lymphocytic leukemia (CLL) is relatively high; however, no predisposing mutation has been convincingly identified. We show that loss or reduced expression of death-associated protein kinase 1 (DAPK1) underlies cases of heritable predisposition to CLL and the majority of sporadic CLL. Epigenetic silencing of DAPK1 by promoter methylation occurs in almost all sporadic CLL cases. Furthermore, we defined a disease haplotype, which segregates with the CLL phenotype in a large family. DAPK1 expression of the CLL allele is downregulated by 75% in germline cells due to increased HOXB7 binding. In the blood cells from affected family members, promoter methylation results in additional loss of DAPK1 expression. Thus, reduced expression of DAPK1 can result from germline predisposition, as well as epigenetic or somatic events causing or contributing to the CLL phenotype.

Evidence for the role of aberrant DNA methylation in the pathogenesis of Lynch syndrome adenomas.

Colorectal cancer (CRC) forms through a series of histologic steps that are accompanied by mutations and epigenetic alterations, which is called the polyp-cancer sequence. The role of epigenetic alterations, such as aberrant DNA methylation, in the polyp-cancer sequence in sporadic CRC and particularly in hereditary colon cancer is not well understood. Consequently, we assessed the methylation status of CDKN2A/p16, MGMT, MLH1 and p14(ARF) in adenomas arising in the Lynch syndrome, a familial colon cancer syndrome caused by MLH1 and MSH2 mutations, to determine if DNA methylation is a "second hit" mechanism in CRC and to characterize the role of DNA methylation in the polyp phase of the Lynch syndrome. We found MLH1 and p14(ARF) are methylated in 53 and 60% of the Lynch syndrome adenomas and in 4 and 20% of sporadic adenomas, whereas CDKN2A/p16 and MGMT are methylated in 6 and 14% of the Lynch syndrome adenomas versus 50 and 64% of sporadic adenomas. Therefore, the frequency and pattern of gene methylation varies between the Lynch syndrome and sporadic colon adenomas, implying differences in the molecular pathogenesis of the tumors. MLH1 methylation in the Lynch syndrome adenomas suggests gene methylation might have a role in the initiation of these neoplasms.

Familial B-cell chronic lymphocytic leukemia: analysis of cytogenetic abnormalities, immunophenotypic profiles, and immunoglobulin heavy chain gene usage.

B-cell chronic lymphocytic leukemia (B-CLL) is a heterogeneous disease that may exhibit familial clustering. We examined the cytogenetic, immunophenotypic, and VH gene usage characteristics of a family with B-CLL affecting 7 members in 3 generations. Interphase fluorescence in situ hybridization studies identified an acquired deletion of chromosome 13q14 in the leukemic cells of 6 affected members, accompanied by deletion 14q32 or trisomy 12 in 2 cases. VH gene analysis demonstrated clonal rearrangements of the VH3 gene family in 5 cases and of VH2 genes in 1 case. All 6 cases were mutated in VH2 or VH3. Two cases had a second VH1 family gene rearrangement that was unmutated. Flow cytometry performed on 5 cases showed the typical B-CLL immunophenotype; all were CD38-, but 3 expressed ZAP-70. Our findings support previous observations that familial and sporadic B-CLL cases are biologically similar and suggest that familial clusters will be useful for studying pathogenetic events in B-CLL.

Prediction of germline mutations and cancer risk in the Lynch syndrome.

CONTEXT: Identifying families at high risk for the Lynch syndrome (ie, hereditary nonpolyposis colorectal cancer) is critical for both genetic counseling and cancer prevention. Current clinical guidelines are effective but limited by applicability and cost. OBJECTIVE: To develop and validate a genetic counseling and risk prediction tool that estimates the probability of carrying a deleterious mutation in mismatch repair genes MLH1, MSH2, or MSH6 and the probability of developing colorectal or endometrial cancer. DESIGN, SETTING, AND PATIENTS: External validation of the MMRpro model was conducted on 279 individuals from 226 clinic-based families in the United States, Canada, and Australia (referred between 1993-2005) by comparing model predictions with results of highly sensitive germline mutation detection techniques. MMRpro models the autosomal dominant inheritance of mismatch repair mutations, with parameters based on meta-analyses of the penetrance and prevalence of mutations and of the predictive values of tumor characteristics. The model's prediction is tailored to each individual's detailed family history information on colorectal and endometrial cancer and to tumor characteristics including microsatellite instability. MAIN OUTCOME MEASURE: Ability of MMRpro to correctly predict mutation carrier status, as measured by operating characteristics, calibration, and overall accuracy. RESULTS: In the independent validation, MMRpro provided a concordance index of 0.83 (95% confidence interval, 0.78-0.88) and a ratio of observed to predicted cases of 0.94 (95% confidence interval, 0.84-1.05). This results in higher accuracy than existing alternatives and current clinical guidelines. CONCLUSIONS: MMRpro is a broadly applicable, accurate prediction model that can contribute to current screening and genetic counseling practices in a high-risk population. It is more sensitive and more specific than existing clinical guidelines for identifying individuals who may benefit from MMR germline testing. It is applicable to individuals for whom tumor samples are not available and to individuals in whom germline testing finds no mutation.

Risk of colon cancer in hereditary non-polyposis colorectal cancer patients as predicted by fuzzy modeling: Influence of smoking.

AIM: To investigate whether a fuzzy logic model could predict colorectal cancer (CRC) risk engendered by smoking in hereditary non-polyposis colorectal cancer (HNPCC) patients. METHODS: Three hundred and forty HNPCC mismatch repair (MMR) mutation carriers from the Creighton University Hereditary Cancer Institute Registry were selected for modeling. Age-dependent curves were generated to elucidate the joint effects between gene mutation (hMLH1 or hMSH2), gender, and smoking status on the probability of developing CRC. RESULTS: Smoking significantly increased CRC risk in male hMSH2 mutation carriers (P < 0.05). hMLH1 mutations augmented CRC risk relative to hMSH2 mutation carriers for males (P < 0.05). Males had a significantly higher risk of CRC than females for hMLH1 non smokers (P < 0.05), hMLH1 smokers (P < 0.1) and hMSH2 smokers (P < 0.1). Smoking promoted CRC in a dose-dependent manner in hMSH2 in males (P < 0.05). Females with hMSH2 mutations and both sexes with the hMLH1 groups only demonstrated a smoking effect after an extensive smoking history (P < 0.05). CONCLUSION: CRC promotion by smoking in HNPCC patients is dependent on gene mutation, gender and age. These data demonstrate that fuzzy modeling may enable formulation of clinical risk scores, thereby allowing individualization of CRC prevention strategies.

History and molecular genetics of Lynch syndrome in family G: a century later.

CONTEXT: In 1895, Aldred Scott Warthin, MD, PhD, initiated one of the most thoroughly documented and longest cancer family histories ever recorded. The unusually high incidence and segregation of cancers of the colon, rectum, stomach, and endometrium in Dr Warthin's family G was later followed up by his colleagues, most recently by Henry Lynch, MD. Described today as a Lynch syndrome family, family G was last documented in 1971, prior to the modern era of molecular diagnostics. OBJECTIVE: To update family G. DESIGN, SETTING, AND PARTICIPANTS: Historical prospective cohort study of family G members from 1895 to 2000. MAIN OUTCOME MEASURES: The primary outcomes were the frequencies and types of cancers, ages at diagnosis, and presence of the T to G transversion at the splice acceptor site of exon 4 of the mutS homolog 2, colon cancer, nonpolyposis type 1 (E coli) (MSH2) gene in family G members. A secondary analysis compared cancer-specific incidence rates in family G with published national and regional cancer incidence rates through the standardized incidence ratio (SIR). RESULTS: Family G now has 929 known descendants of the original progenitor first reported in 1913. Cancers of the colon and rectum (SIR, 3.20; 95% confidence interval [CI], 2.39-4.19) and endometrium (SIR, 3.51; 95% CI, 1.92-5.89) continue to predominate in family G. Five of 40 tested members of family G carry the MSH2 T to G mutation; as a result, 15 of their living relatives are at increased risk of developing 1 or more colorectal or Lynch syndrome-associated cancers. In contrast, 97 living members of family G can now be excluded as mutation carriers. CONCLUSION: Within the last decade, molecular diagnostic testing has transformed the care of family G and other Lynch syndrome families in which a pathogenic mutation has been identified.