Swiss cost-effectiveness analysis of universal screening for Lynch syndrome of patients with colorectal cancer followed by cascade genetic testing of relatives.

BACKGROUND: We estimated the cost-effectiveness of universal DNA screening for Lynch syndrome (LS) among newly diagnosed patients with colorectal cancer (CRC) followed by cascade screening of relatives from the Swiss healthcare system perspective. METHODS: We integrated decision trees with Markov models to calculate incremental cost per quality-adjusted life-year saved by screening all patients with CRC (alternative strategy) compared with CRC tumour-based testing followed by DNA sequencing (current strategy). RESULTS: The alternative strategy has an incremental cost-effectiveness ratio of CHF65 058 compared with the current strategy, which is cost-effective according to Swiss standards. Based on annual incidence of CRC in Switzerland, universal DNA screening correctly identifies all 123 patients with CRC with LS, prevents 17 LS deaths and avoids 19 CRC cases, while the current strategy leads to 32 false negative results and 253 LS cases lost to follow-up. One way and probabilistic sensitivity analyses showed that universal DNA testing is cost-effective in around 80% of scenarios, and that the cost of DNA testing and the number of invited relatives per LS case determine the cost-effectiveness ratio. CONCLUSION: Results can inform policymakers, healthcare providers and insurance companies about the costs and benefits associated with universal screening for LS and cascade genetic testing of relatives.

Evidence for breast cancer as an integral part of Lynch syndrome.

Lynch syndrome, an autosomal dominant cancer predisposition caused by mutations in DNA mismatch repair (MMR) genes, mainly mainly mutL homolog 1, OMIM 120436 (MLH1) and mutS homolog 2, OMIM 609309 (MSH2), encompasses a tumor spectrum including primarily gastrointestinal, endometrial, and ovarian cancer. This study aimed at clarifying the heavily debated issue of breast cancer being part of Lynch syndrome. Detailed clinical data on cancer occurrence in Swiss female MLH1/MSH2 mutation carriers were gathered, all available breast cancer specimens assessed for molecular evidence for MMR deficiency (i.e., microsatellite instability (MSI), MMR protein expression, and somatic (epi)genetic MMR gene alterations) and compiled with the scarce molecular data available from the literature. Seventy unrelated Swiss Lynch syndrome families were investigated comprising 632 female family members at risk of which 92 were genetically verified mutation carriers (52 MLH1 and 40 MSH2). On contrast to endometrial and ovarian cancer, which occurred significantly more often and at younger age in MLH1/MSH2 mutation carriers (median 50.5 and 49.0 years; P < 0.00001), overall cumulative breast cancer incidence closely mirrored the one in the Swiss population (56.5 years). Six (85.7%) of seven breast cancer specimens available for molecular investigations displayed the hallmarks of MMR deficiency. Combined with data from the literature, MSI was present in 26 (70.3%) of 37 and altered MMR protein expression in 16 (72.7%) of 22 breast cancer specimens from MLH1/MSH2 mutation carriers. These findings, thus, provide strong molecular evidence for a pivotal role of MMR deficiency in breast cancer development in Lynch syndrome.

Circulating cell-free DNA as a potential biomarker for minimal and mild endometriosis.

It has recently been reported that high concentrations of circulating cell-free (ccf) nucleic acids in plasma and serum could be used as biomarkers for non-invasive monitoring a wide variety of malignant and benign proliferations and inflammatory conditions. Endometriosis is one of the most common benign gynaecological proliferations with inflammatory activation in premenopausal women. Real-time multiplex polymerase chain reaction was used for synchronized quantification of the glyceraldehyde-3-phosphate dehydrogenase gene sequence in nuclear DNA (nDNA) and the ATP synthase-8 gene sequence in mitochondrial DNA (mtDNA). DNA was extracted from 500 microl serum and plasma of 19 cases with endometriosis to measure the total amount of ccf nDNA and ccf mtDNA. The concentration of ccf nDNA in plasma was significantly higher in the endometriosis group than in the control group (P = 0.046). The cut-off value selected by a receiver operating characteristic curve could provide a sensitivity of 70% and a specificity of 87% to discriminate between the minimal or mild cases and normal controls. The finding of significantly increased concentrations of ccf nDNA in plasma of patients with endometriosis suggests that ccf nDNA might be a potential biomarker for developing non-invasive diagnostic test in endometriosis.

Levels of circulating cell-free nuclear and mitochondrial DNA in benign and malignant ovarian tumors.

OBJECTIVE: To analyze the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in patients with benign and malignant ovarian tumors using a gold-standard assay and to investigate whether quantitative alterations of the circulating cell-free species have values in the management of the patients. METHODS: One hundred four patients were recruited for this study. We developed a quantitative, multiplex polymerase chain reaction to measure the levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in serum and plasma of patients with epithelial ovarian cancer, benign epithelial ovarian tumors, or endometriosis. The levels of the circulating cell-free DNA were compared with those of a healthy, age-matched control group. RESULTS: The patients with epithelial ovarian cancer had significantly higher amounts of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in plasma compared with the healthy control group (mean of nuclear DNA 10,723/2,591 and mean of mitochondrial DNA 4,918,978/2,294,264, P=.009 and 0.022, respectively) and with the other group with benign ovarian diseases (mean of nuclear DNA 10,723/2,965 and mean of mitochondrial DNA 4,918,978/1,597,551, P=.027 and 0.002, respectively). However, no relationship between levels of the circulating cell-free DNA and the pathological parameters as well as CA 125 measurement in patients with epithelial ovarian cancer was found. A significant difference between the epithelial ovarian cancer and endometriosis group was found in circulating cell-free mitochondrial DNA but not in circulating cell-free nuclear DNA (mean of mitochondrial DNA 4,918,978/2,273,988 and mean of nuclear DNA 10,723/3,291, P=.013 and 0.105, respectively). CONCLUSION: Elevated levels of circulating cell-free nuclear DNA and circulating cell-free mitochondrial DNA in epithelial ovarian cancer may have diagnostic value. Our finding suggests that the circulating molecules might be potential biomarkers in the disease.

Cancer Predisposition Cascade Screening for Hereditary Breast/Ovarian Cancer and Lynch Syndromes in Switzerland: Study Protocol.

BACKGROUND: Breast, colorectal, ovarian, and endometrial cancers constitute approximately 30% of newly diagnosed cancer cases in Switzerland, affecting more than 12,000 individuals annually. Hundreds of these patients are likely to carry germline pathogenic variants associated with hereditary breast ovarian cancer (HBOC) or Lynch syndrome (LS). Genetic services (counseling and testing) for hereditary susceptibility to cancer can prevent many cancer diagnoses and deaths through early identification and risk management. OBJECTIVE: Cascade screening is the systematic identification and testing of relatives of a known mutation carrier. It determines whether asymptomatic relatives also carry the known variant, needing management options to reduce future harmful outcomes. Specific aims of the CASCADE study are to (1) survey index cases with HBOC or LS from clinic-based genetic testing records and determine their current cancer status and surveillance practices, needs for coordination of medical care, psychosocial needs, patient-provider and patient-family communication, quality of life, and willingness to serve as advocates for cancer genetic services to blood relatives, (2) survey first- and second-degree relatives and first-cousins identified from pedigrees or family history records of HBOC and LS index cases and determine their current cancer and mutation status, cancer surveillance practices, needs for coordination of medical care, barriers and facilitators to using cancer genetic services, psychosocial needs, patient-provider and patient-family communication, quality of life, and willingness to participate in a study designed to increase use of cancer genetic services, and (3) explore the influence of patient-provider communication about genetic cancer risk on patient-family communication and the acceptability of a family-based communication, coping, and decision support intervention with focus group(s) of mutation carriers and relatives. METHODS: CASCADE is a longitudinal study using surveys (online or paper/pencil) and focus groups, designed to elicit factors that enhance cascade genetic testing for HBOC and LS in Switzerland. Repeated observations are the optimal way for assessing these outcomes. Focus groups will examine barriers in patient-provider and patient-family communication, and the acceptability of a family-based communication, coping, and decision-support intervention. The survey will be developed in English, translated into three languages (German, French, and Italian), and back-translated into English, except for scales with validated versions in these languages. RESULTS: Descriptive analyses will include calculating means, standard deviations, frequencies, and percentages of variables and participant descriptors. Bivariate analyses (Pearson correlations, chi-square test for differences in proportions, and t test for differences in means) will assess associations between demographics and clinical characteristics. Regression analyses will incorporate generalized estimating equations for pairing index cases with their relatives and explore whether predictors are in direct, mediating, or moderating relationship to an outcome. Focus group data will be transcribed verbatim and analyzed for common themes. CONCLUSIONS: Robust evidence from basic science and descriptive population-based studies in Switzerland support the necessity of cascade screening for genetic predisposition to HBOC and LS. CASCADE is designed to address translation of this knowledge into public health interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT03124212; https://clinicaltrials.gov/ct2/show/NCT03124212 (Archived by WebCite at http://www.webcitation.org/6tKZnNDBt).