Sequential first-line treatment with nab-paclitaxel/gemcitabine and FOLFIRINOX in metastatic pancreatic adenocarcinoma: GABRINOX phase Ib-II controlled clinical trial.

BACKGROUND: Nab-paclitaxel/gemcitabine (AG) and FOLFIRINOX (FFX) are promising drugs in metastatic pancreatic cancer (MPC). This study evaluated a new first-line sequential treatment (AG followed by FFX) in MPC that might overcome resistance to primary therapy and delay tumor progression. PATIENTS AND METHODS: Patients with histologically/cytologically confirmed MPC were included in a multicentric trial receiving AG (day 1, 8 and 15) followed by FFX (day 29 and 43). In phase Ib, three dose-levels were tested for maximum tolerated dose (MTD) and recommended phase II dose. In phase II, the main outcome was the objective response rate (ORR) and secondarily safety, progression-free survival (PFS) and overall survival (OS). RESULTS: In phase Ib, we included 33 patients (31 assessable) of median age 61.0 years (range 42-75 years) and represented by 54.8% males. Five dose-limiting toxicities were reported without any death. The main grade 3/4 toxicities were neutropenia with spontaneous resolution (35.5%/32.3%), venous thromboembolism (grade 3: 22.6%) and thrombopenia (grade 3: 29.0%), while the MTD was not reached. In phase II, we included 58 patients of median age 60 years (range 34-72 years), 50% males and with Eastern Cooperative Oncology Group stage score 0 and 1 of 37.9% and 62.1%, respectively. They received a median of 4 (1-9) cycles in 8.5 months (0.5-19.8 months). The ORR was 64.9% [95% confidence interval (CI) 51.1% to 77.1%], and neurotoxicity was remarkably low. The main grade 3-4 toxicities were venous thromboembolism, thrombopenia, neutropenia/febrile neutropenia, nausea, diarrhea, weight loss and asthenia without any death. Tumor response was complete in 3.5% and partial in 61.4%, while disease was stable in 19.3% and progressive in 15.8% of patients. The median PFS was 10.5 months (95% CI 6.0-12.5 months) and median OS was 15.1 months (95% CI 10.6-20.1 months). CONCLUSION: Sequential AG and FFX showed acceptable toxicity as first-line treatment with no limiting neurotoxicity, while high response rate and survival justify randomized trials.

Immune checkpoint inhibitor treatment of a first cancer is associated with a decreased incidence of second primary cancer.

BACKGROUND: Second primary cancers (SPCs) are diagnosed in over 5% of patients after a first primary cancer (FPC). We explore here the impact of immune checkpoint inhibitors (ICIs) given for an FPC on the risk of SPC in different age groups, cancer types and treatments. PATIENTS AND METHODS: The files of the 46 829 patients diagnosed with an FPC in the Centre Léon Bérard from 2013 to 2018 were analyzed. Structured data were extracted and electronic patient records were screened using a natural language processing tool, with validation using manual screening of 2818 files of patients. Univariate and multivariate analyses of the incidence of SPC according to patient characteristics and treatment were conducted. RESULTS: Among the 46 829 patients, 1830 (3.9%) had a diagnosis of SPC with a median interval of 11.1 months (range 0-78 months); 18 128 (38.7%) received cytotoxic chemotherapy (CC) and 1163 (2.5%) received ICIs for the treatment of the FPC in this period. SPCs were observed in 7/1163 (0.6%) patients who had received ICIs for their FPC versus 437/16 997 (2.6%) patients receiving CC and no ICIs for the FPC versus 1386/28 669 (4.8%) for patients receiving neither CC nor ICIs for the FPC. This reduction was observed at all ages and for all histotypes analyzed. Treatment with ICIs and/or CC for the FPC are associated with a reduced risk of SPC in multivariate analysis. CONCLUSION: Immunotherapy with ICIs alone and in combination with CC was found to be associated with a reduced incidence of SPC for all ages and cancer types.

FOLFIRINOX in patients with peritoneal carcinomatosis from pancreatic adenocarcinoma: a retrospective study.

Background: Peritoneal carcinomatosis (pcm) in metastatic pancreatic ductal adenocarcinomas (mpdac) is frequently encountered in day-to-day practice, but rarely addressed in the literature. The objective of the present study was to describe the management and outcome of patients diagnosed with pcm. Methods: Data for all consecutive patients with mpdac treated in our centre between 1 January 2014 and 31 August 2015 were analyzed retrospectively. Computed tomography imaging was centrally reviewed by a dedicated radiologist to determine the date of pcm diagnosis. Results: The analysis included 48 patients. Median age in the group was 61 years, and 41 patients had an Eastern Cooperative Oncology Group performance status (ecog ps) of 0-1. All patients presented with pcm either synchronously (group 1) or metachronously (group 2). Those groups differed significantly by baseline ecog ps and neutrophil-to-lymphocyte ratio (nlr), with ecog ps being poorer and nlr being higher in group 1. In addition to pcm, the main sites of metastasis were liver (62.5%) and lungs (31.3%). First-line chemotherapy in 36 patients (75%) was folfirinox (fluorouracil-irinotecan-leucovorin-oxaliplatin). The median overall survival for the entire population was 10.81 months [95% confidence interval (ci): 7.16 months to 14.16 months]; it was 13.17 months (95% ci: 5.9 months to 15.4 months) for patients treated with folfirinox. Median overall survival was 7.13 months (95% ci: 4.24 months to 10.41 months) for patients in group 1 and 14.34 months (95% ci: 9.79 months to 19.91 months) for patients in group 2, p = 0.1296. Conclusions: Compared with other metastatic sites, synchronous pcm seems to be a poor prognostic factor. It could be more frequently associated with a poor ecog ps and a nlr greater than 5 in this group of patients. In patients with mpdac and pcm, either synchronous or metachronous, folfirinox remains an efficient regimen.

Molecular screening program to select molecular-based recommended therapies for metastatic cancer patients: analysis from the ProfiLER trial.

BACKGROUND: Antitumor activity of molecular-targeted agents is guided by the presence of documented genomic alteration in specific histological subtypes. We aim to explore the feasibility, efficacy and therapeutic impact of molecular profiling in routine setting. PATIENTS AND METHODS: This multicentric prospective study enrolled adult or pediatric patients with solid or hematological advanced cancer previously treated in advanced/metastatic setting and noneligible to curative treatment. Each molecular profile was established on tumor, relapse or biopsies, and reviewed by a molecular tumor board (MTB) to identify molecular-based recommended therapies (MBRT). The main outcome was to assess the incidence rate of genomic mutations in routine setting, across specific histological types. Secondary objectives included a description of patients with actionable alterations and for whom MBRT was initiated, and overall response rate. RESULTS: Four centers included 2579 patients from February 2013 to February 2017, and the MTB reviewed the molecular profiles achieved for 1980 (76.8%) patients. The most frequently altered genes were CDKN2A (N = 181, 7%), KRAS (N = 177, 7%), PIK3CA (N = 185, 7%), and CCND1 (N = 104, 4%). An MBRT was recommended for 699/2579 patients (27%), and only 163/2579 patients (6%) received at least one MBRT. Out of the 182 lines of MBRT initiated, 23 (13%) partial responses were observed. However, only 0.9% of the whole cohort experienced an objective response. CONCLUSION: An MBRT was provided for 27% of patients in our study, but only 6% of patients actually received matched therapy with an overall response rate of 0.9%. Molecular screening should not be used at present to guide decision-making in routine clinical practice outside of clinical trials.This trial is registered with ClinicalTrials.gov, number NCT01774409.

Thrombocytopenia due to hypersplenism in oncological disease: partial splenic embolization during palliative treatment.

Hypersplenism is excess activity of the spleen, resulting in peripheral pancytopenia that predominates in platelet cell lines. Pancytopenia can be limited by reducing the volume of the functional spleen. However, in patients in very poor general condition, a splenectomy may not be possible, due to the risks of surgery and postoperative infection. Another therapeutic alternative in these patients is to reduce the volume of the spleen by super selective percutaneous splenic embolization. We report three cases of peripheral thrombocytopenia due to hypersplenism with a platelet count between 60,000 and 80,000/mm(3), which made it impossible to continue or start a chemotherapy protocol in these patients. For these patients, super selective partial embolization of the splenic parenchyma, with uncharged microspheres (250 microns) quickly resulted in a platelet count above 150,000/mm(3) so that chemotherapy could be continued or initiated.

Sorafenib and irinotecan (NEXIRI) as second- or later-line treatment for patients with metastatic colorectal cancer and KRAS-mutated tumours: a multicentre Phase I/II trial.

BACKGROUND: This trial evaluated the feasibility and efficacy of combined sorafenib and irinotecan (NEXIRI) as second- or later-line treatment of patients with KRAS-mutated metastatic colorectal cancer (mCRC), who had progressed after irinotecan-based chemotherapy. METHODS: In Phase I, in a 3+3 dose escalation schedule, patients received irinotecan (125, 150 or 180 mg m(-2) every 2 weeks), in combination with 400 mg sorafenib b.d. The primary end point was the maximum-tolerated dose of irinotecan. In Phase II, the primary end point was disease control rate (DCR). Secondary end points were progression-free survival (PFS), overall survival (OS) and toxicity. RESULTS: Phase I included 10 patients (median age 63 (49-73)); no dose-limiting toxicity was seen. In Phase II, 54 patients (median age 60 (43-80) years) received irinotecan 180 mg m(-)(2) every 2 weeks with sorafenib 400 mg b.d. Nine patients (17%) remained on full-dose sorafenib. The DCR was 64.9% (95% CI, 51-77). Median PFS and OS were 3.7 (95% CI, 3.2-4.7) and 8.0 (95% CI, 4.8-9.7) months, respectively. Toxicities included Grade 3 diarrhoea (37%), neutropenia (18%), hand-foot syndrome (13%) and Grade 4 neutropenia (17%). CONCLUSION: The NEXIRI regimen showed promising activity as second- or later-line treatment in this heavily pretreated mCRC population (ClinicalTrials.gov NCT00989469).

Circulating tumor cells in locally advanced pancreatic adenocarcinoma: the ancillary CirCe 07 study to the LAP 07 trial.

BACKGROUND: Pancreatic carcinoma is one of the leading causes of cancer-related mortality. At the time of diagnosis, 30% of patients present with a locally advanced pancreatic carcinoma (LAPC). As circulating tumor cells (CTCs) count may be a surrogate of the cancer metastatic abilities, CTC detection rates and prognostic value were studied in a prospective cohort of LAPC patients. PATIENTS AND METHODS: An LAP07 international multicenter randomized study assesses in patients whose LAPC is controlled after 4 months of chemotherapy whether chemoradiotherapy could increase survival versus continuation of chemotherapy. A subgroup of patients included in the LAP07 trial was screened for CTCs (CellSearch®) before the start of the chemotherapy and after 2 months of treatment. Patient characteristics and survival were obtained prospectively and were correlated with CTC detection. RESULTS: Seventy-nine patients were included. One or more CTCs/7.5 ml were detected in 5% of patients before treatment and in 9% of patients after 2 months of treatment (overall detection rate: 11% of patients). CTC positivity was associated with poor tumor differentiation (P = 0.04), and with shorter overall survival (OS) in multivariable analysis (RR = 2.5, P = 0.01), together with anemia. CONCLUSIONS: The evaluation of micrometastatic disease using CTC detection appears as a promising prognostic tool in LAPC patients.

Efficacy of irinotecan in combination with 5-fluorouracil (FOLFIRI) for metastatic gastric or gastroesophageal junction adenocarcinomas (MGA) treatment.

OBJECTIVES: The most commonly used schedules are 5-FU in combination with CDDP with or without epirubicin (ECF) or docetaxel (TCF) in treatment of MGA patients (pts), independently of HER status. We evaluated the efficacy of FOLFIRI regimen in a large retrospective series of MGA pts. METHODS: Two hundred and twelve pts from 13 French centers were treated with at least one cycle of FOLFIRI (irinotecan 180 mg/m2 intravenous (i.v.) over 90 minutes on day 1 with folinic acid (FA) 400mg/m2 i.v. over two hours followed by 5-FU 400mg/m2 i.v. bolus then 5- FU 2400 mg/m2 continuous infusion over 46 hours on day 1, repeated every 14 days). Primary tumour sites were 120 (58%) stomach and 92 (42%) gastroesophageal junction. FOLFIRI was administered as first-line in 137 (65%) pts and as later-line in 75 (35%) pts for MGA. RESULTS: There was no difference between chemonaive and not chemonaive pts treated as firstline in terms of response rate 37% (95% CI: 25-50) vs 44% (95% CI: 21-69), median PFS, 6.7 (95% CI: 5.5-9.9) vs 5.3 months (95% CI: 3.6-6.9) (P = 0.25), and OS, 13.1 (95% CI: 11.7-18.7) vs 8.8 months (95% CI: 7.3­15.6) (P = 0.19), respectively. There was no difference between pts treated as second or later-line in terms of response rate 20% (95% CI: 8-39) vs 22% (95% CI: 6-48), median PFS, four months (95% CI: 2.8-5.4) vs 3.5 months (95% CI: 2.3-4.5) (P = 0.56), and OS, 10.4 months (95% CI: 5.4-14.4) vs 5.3 months (95% CI: 3.5-11.3) (P = 0.58), respectively. The global grade 3-4 toxicities were: diarrhea 11%, vomiting 9%, neutropenia 18%, febril neutropenia 4% (one toxic death). CONCLUSIONS: This retrospective study confirms the activity and good tolerance of FOLFIRI regimen in MGA as first-line as well as later-line.

A risk model for severe anemia to select cancer patients for primary prophylaxis with epoetin alpha: a prospective randomized controlled trial of the ELYPSE study group.

BACKGROUND: Epoetin (EPO) administration reduces the need for transfusion. Identifying patients at high risk of anemia requiring red blood cell (RBC) transfusion is needed. This multicentric phase III trial tested epoetin alpha (EPOalpha) administration according to our risk model on the basis of three clinical parameters: hemoglobin (Hb) <12 g/dl, lymphocytes 1. PATIENTS AND METHODS: Patients >or=18 years with chemotherapy-treated solid or hematologic tumors were randomized to 150 UI/kg/TIW s.c. EPOalpha (arm 1) or no EPOalpha (arm 2) and stratified on Hb level at day 0, lymphocyte count, and PS. The primary end point was transfusion rate; secondary end points included overall survival (OS), safety, and quality of life. RESULTS: From September 2000 to January 2005, 218 patients (median age 64 years, 42.7% males) with principally breast cancer, sarcoma, or lung carcinoma were included. In total, 93% patients had PS >1 and 35% had

Tritherapy with fluorouracil/leucovorin, irinotecan and oxaliplatin (FOLFIRINOX): a phase II study in colorectal cancer patients with non-resectable liver metastases.

PURPOSE: To assess the rate of R(0) resection of liver metastases achieved after chemotherapy with FOLFIRINOX. PATIENTS AND METHODS: Patients with histologically proven primary colorectal cancer and bidimensionally measurable liver metastasis, not fully resectable based on technical inability to achieve R(0) resection, but potentially resectable after tumor reduction, were given FOLFIRINOX: oxaliplatin 85 mg/m(2), irinotecan 180 mg/m(2), leucovorin 400 mg/m(2), bolus fluorouracil 400 mg/m(2) and fluorouracil 46-h continuous IV infusion 2,400 mg/m(2), every 2 weeks for a maximum of 12 cycles. RESULTS: Thirty-four patients were enrolled. Response rate before surgery was 70.6% (95%CI: 52.5-84.9). Twenty-eight patients (82.4%) underwent hepatic resection and nine achieved R(0) resection [26.5% (95% CI: 12.9-44.4%)]. The rate of clinical complete remission after surgery was 79.4%. Two-year overall survival was 83%. The most frequent grade 3 or 4 toxicities were neutropenia (64.8%), diarrhea (29.4%), fatigue (23.5%), abdominal cramps (14.7%), neuropathy and nausea (11.8% each), and AST/ALT elevation (14.7/11.8%). Only one patient experienced febrile neutropenia, four patients withdrew due to toxicity and no toxic death was observed. CONCLUSION: FOLFIRINOX, with an acceptable toxicity profile, shows a high response rate in liver metastases from colorectal cancer. The rate of hepatic resection in patients initially not resectable, is attractive and warrants further assessment of this regimen in randomized studies compared to standard regimens.

Phase II study of UFT with leucovorin and irinotecan (TEGAFIRI): first-line therapy for metastatic colorectal cancer.

This phase II trial was performed to evaluate the efficacy and tolerability of oral tegafur-uracil (UFT) with leucovorin (LV) combined with intravenous (i.v.) irinotecan every 3 weeks (TEGAFIRI) as first-line treatment for patients with metastatic colorectal cancer (mCRC). Patients received oral UFT 250 mg m(-2) day(-1) and LV 90 mg day(-1) in three divided daily doses for 14 days followed by a 1-week rest and i.v. irinotecan 250 mg m(-2) as a 90-min infusion every 3 weeks. Tumour responses, assessed every two cycles using RECIST criteria, were reviewed by an independent review committee. In 52 evaluable patients, the best overall response rate was 33% (95% confidence intervals (CI) 20-47%; 1 complete and 16 partial responses). The median time to progression was 5.4 months (95% CI 3.02-7.52 months) and median overall survival was 14.9 months (11.73-17.97 months). A total of 307 cycles were administered, with a median number of five cycles per patient (range: 1-10). The most common grade 3/4 toxicities were neutropenia (25% of patients), diarrhoea (22%), vomiting (11%) and anaemia (11%). The TEGAFIRI regimen is a feasible, well-tolerated and convenient treatment option for patients with non-resectable mCRC.

Assessment of tumour response to chemotherapy for metastatic colorectal cancer: accuracy of the RECIST criteria.

Evaluation of tumour size modifications in response to treatment is a critical issue in the management of advanced malignancies. In 1981, the World Health Organization (WHO) established guidelines for tumour response assessment. These WHO1981 criteria were recently simplified in a revised version, named RECIST (Response Evaluation Criteria in Solid Tumours), which uses unidimensional instead of bidimensional measurements, a reduced number of measured lesions, withdrawal of the progression criteria based on isolated increase of a single lesion, and different shrinkage threshold for definitions of tumour response and progression. In order to validate these new guidelines, we have compared results obtained with both classifications in a prospective series of 91 patients receiving chemotherapy for metastatic colorectal cancer. Data from iterative tomographic measurements were fully recorded and reviewed by an expert panel. The overall response and progression rates according to the WHO1981 criteria were 19% and 58%, respectively. Using RECIST criteria, 16 patients were reclassified in a more favourable subgroup, the overall response rate being 28% and the progression rate 45% (non-weighted kappa concordance test 0.72). When isolated increase of a single measurable lesion is not taken into account for progression with the WHO1981 criteria, only 7 patients were reclassified and the kappa test was satisfying, i.e. > or =0.75, for the whole population as well as for each of the responding and progressive subgroups. Since it provides concordant results with a simplified method, the use of RECIST criteria is recommended for evaluation of treatment efficacy in clinical trials and routine practice.

High-dose, single-agent irinotecan as first-line therapy in the treatment of metastatic colorectal cancer.

PURPOSE: The efficacy and safety of single-agent, high-dose irinotecan (CPT-11, Campto) 500 mg/m(2) every 3 weeks were investigated as first-line treatment for advanced colorectal cancer (CRC). PATIENTS AND METHODS: Patients were enrolled into the study to receive a first cycle of therapy with irinotecan at a dose of 350 mg/m(2) every 3 weeks, which could be escalated to 500 mg/m(2) for the second and subsequent cycles depending on toxicity. Efficacy, safety and pharmacokinetics were determined in the intent to treat (ITT) population and the high-dose population (i.e. patients who had received at least three cycles of irinotecan, the second and third at 500 mg/m(2)). RESULTS: Of 49 patients enrolled into the study (ITT population), 31 (63%) received at least three cycles of treatment with cycles 2 and 3 at an irinotecan dose of 500 mg/m(2) (the high-dose population). The response rates (RR) for the ITT and high-dose populations were 24.5% and 35.5%, respectively. The main grade 3/4 toxicities per cycle in the ITT and high-dose populations were neutropenia 22% and 17%, febrile neutropenia 5% and 3%, and diarrhoea 12% and 7%, respectively. The pharmacokinetics of irinotecan and its metabolite SN-38 were investigated in 31 patients in cycle 1 and 22 patients in cycle 2. Irinotecan clearance and SN-38 exposure were not sufficiently correlated with toxicity in cycle 1 to identify patients for dose increase in subsequent cycles. The exposure to irinotecan and SN-38 increased in proportion to dose from 350 to 500 mg/m(2). CONCLUSION: These results suggest that high-dose irinotecan can be safely administered as first-line monotherapy to approximately two-thirds of patients who present with advanced CRC following a selective first cycle.

[Curative treatment of non-metastatic esophageal cancer: concomitant chemoradiotherapy and high-dose-rate endoluminal curietherapy boost]. / Traitement à visée curative du cancer de l'oesophage non métastatique: chimio-radiothérapie concomitante et surdosage par curiethérapie endoluminale à haut débit de dose.

OBJECTIVES: The aim of this study was to evaluate the feasibility, toxicity, and efficacy of a curative combination of chemo-radiotherapy with high-dose-rate brachytherapy (HDRB) in patients with non metastatic esophageal cancer. PATIENTS AND METHODS: Fifty-two patients with esophageal carcinoma were treated with > 50 Gy external irradiation, concomitant chemotherapy (5FU-CDDP) followed by HDRB delivering 12.5 Gy (6-20) as a boost. Twelve patients were stage I, 20 stage IIa, 5 stage IIb, and 13 stage III, 1 Tis, 1 stage N unknown. Surgery was not indicated for medical reasons. RESULTS: The response rate was 96%, with complete response rate 85%. The 1-, 3-, 5-year overall survival rates were 78%, 33%, and 22% respectively. A local failure occurred in 32%, and distant metastasis in 16%. Severe (grade 3, 4) acute toxicity occurred in 6 cases, severe late toxicity in 2 cases and there was 1 toxic death. Tumoral length > or = 5 cm and stage IIa, IIb and III versus stage 1 indicated poor prognosis. CONCLUSION: This regimen is feasible and well tolerated. The 5-year overall survival is 22%, but the local failure rate is still very high. These results are encouraging and will be prospectively evaluated with currently ongoing randomized trial.

Multicenter phase II study of bimonthly high-dose leucovorin, fluorouracil infusion, and oxaliplatin for metastatic colorectal cancer resistant to the same leucovorin and fluorouracil regimen.

PURPOSE: To evaluate the objective tumor response rates and toxicities of leucovorin (LV) plus fluorouracil (5-FU) cancer regimen combined with oxaliplatin (85 mg/m(2)) every 2 weeks on metastatic colorectal cancer patients with documented proof of progression while on bimonthly LV and 5-FU alone. PATIENTS AND METHODS: One hundred patients were enrolled onto this study and 97 received the study drugs between October 1995 and December 1996. Eighty-nine patients were eligible for per-protocol efficacy analysis with documented proof of progression on one of the following two treatments: LV 500 mg/m(2) and continuous 5-FU infusion 1.5 to 2 g/m(2)/22 hours, days 1 through 2 every 2 weeks (FOLFUHD); or LV 200 mg/m(2), bolus 5-FU 400 mg/m(2), and continuous 5-FU infusion 600 mg/m(2)/22 hours, days 1 through 2 every 2 weeks (LV5FU2). In our study, 40 patients received FOLFUHD + 85 mg/m(2) of oxaliplatin day 1 (FOLFOX3) and 57 patients received LV5FU2 + 85 mg/m(2) of oxaliplatin day 1 (FOLFOX4). RESULTS: Of the 97 patients treated, 20 partial responses were observed (FOLFOX3/4: response rate, 20.6%; 95% confidence interval, 13% to 31.1%; FOLFOX3: response rate,18.4%; FOLFOX4: response rate, 23.5%). For patients treated with FOLFOX3/4, the median response duration for was 7.5 months, and the major toxicities were peripheral neuropathy and neutropenia. The incidence of grade 3 (National Cancer Institute common toxicity criteria) peripheral neuropathy was 20.6%; whereas the overall incidence of grade 3 to 4 neutropenia was 27.8%, 15%, and 36.9% for FOLFOX3/4, FOLFOX3, and FOLFOX4, respectively (P =.02). From the start of treatment, median progression-free survival was 4. 7, 4.6, and 5.1 months for FOLFOX3/4, FOLFOX3, FOLFOX4, respectively, and median overall survival was 10.8, 10.6, and 11.1 months, respectively. CONCLUSION: This phase II study of oxaliplatin at 85 mg/m(2) in combination with bimonthly LV plus 5-FU in patients with colorectal cancer resistant to LV plus 5-FU alone confirms the enhanced antitumor activity of oxaliplatin in combination with 5-FU.

Prevalence of germline mutations of hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 genes in 75 French kindreds with nonpolyposis colorectal cancer.

Hereditary nonpolyposis colorectal cancer (HNPCC) is a syndrome characterized by familial predisposition to colorectal carcinoma and extracolonic cancers of the gastrointestinal, urological, and female reproductive tracts. This dominant disorder is caused by germline defects in one of at least five DNA mismatch repair (MMR) genes: hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 (GTBP). Germline mutations of hMSH2 and hMLH1 are also frequently identified in families not fulfilling all the Amsterdam criteria, thereby demonstrating that the involvement of these genes is not confined to typical HNPCC. To evaluate the respective involvement of the various MMR genes in typical and incomplete HNPCC syndromes, we have performed an analysis of the hMLH1, hMSH2, hPMS1, hPMS2, and hMSH6 genes in a large series of French kindreds (n=75) with colorectal tumors and/or aggregation of extracolonic cancers belonging to the HNPCC spectrum. Mutational analysis has been performed in all families, without preselection for the tumor phenotype. We have detected 26 pathogenic germline mutations of the hMLH1 and hMSH2 genes and several novel variants of the hPMS1, hPMS2, and hMSH6 genes. Our data confirm that, regardless of the type of families and the tumor phenotype, hPMS1, hPMS2, and hMSH6 germline mutations are rare in familial aggregation of colorectal cancers. Furthermore, they suggest that the presence of multiple primary malignancies in a single individual and the observation of extracolonic tumors in relatives of a colorectal cancer patient should be included among the guidelines for referring patients for genetic testing.

Neurofibromatosis and early onset of cancers in hMLH1-deficient children.

Hereditary nonpolyposis colon cancer is a common hereditary disorder caused by the germ-line mutations of DNA mismatch repair (MMR) genes, especially hMLH1 and hMSH2. We report here the first identification of human compounds with a homozygous inactivation of a MMR gene. In a typical hereditary nonpolyposis colon cancer family, MMR-deficient children conceived from matings between heterozygotes for a hMLH1 deleterious mutation exhibited clinical features of de novo neurofibromatosis type I and early onset of extracolonic cancers. This observation demonstrates that MMR deficiency is compatible with human development but may lead to mutations during embryogenesis. On the basis of clinical symptoms observed in MMR-deficient children, we speculate that the neurofibromatosis type 1 gene is a preferential target for such alterations.

Germline hMSH2 and hMLH1 gene mutations in incomplete HNPCC families.

Hereditary non-polyposis colon cancer (HNPCC) is a common hereditary disease characterized by a predisposition to an early onset of colorectal cancer. The majority of the HNPCC families carry germline mutations of either hMSH2 or hMLH1 genes, whereas germline mutations of hPMS1 and hPMS2 genes have rarely been observed. Almost all of the germline mutations reported so far concern typical HNPCC families. However, there are families that display aggregations of colon cancer even though they do not fulfil all HNPCC criteria (incomplete HNPCC families) as well as sporadic cases of early onset colon cancers that could be related to germline mutations of these genes. Therefore, we screened germline mutations of hMSH2 and hMLH1 genes in 3 groups of patients from France and Turkey: typical HNPCC (n = 3), incomplete HNPCC (n = 9) and young patients without apparent familial history (n = 7). By in vitro synthesis of protein assay, heteroduplex analysis and direct genomic sequencing, we identified 1 family with hMSH2 mutation and 5 families with hMLH1 mutations. Two of the 3 HNPCC families (66%) displayed hMLH1 germline mutations. Interestingly, 4 of 9 families with incomplete HNPCC (44%) also displayed mutations of hMSH2 or hMLH1 genes. In contrast, no germline mutation of these genes was found in 7 young patients. Our results show that germline mutations of hMSH2 and hMLH1 genes contribute to a significant fraction of familial predisposition to colon cancer cases that do not fulfil all diagnostic criteria of HNPCC.