Lynch syndrome: influence of additional susceptibility variants on cancer risk

Some patients with Lynch syndrome (LS) have extreme phenotypes, i.e. cancer before the recommended screening age, or cancer for which there are no screening guidelines. We made the hypothesis that additional germline variants in cancer susceptibility genes (CSG) could explain some of these phenotypes. We compared the prevalence of additional CSG variants in LS patients with a cancer diagnosis before age 30 (early-onset, EO group) and after 40 (usual-onset, UO group). While there was no overall difference, we did find an excess of pathogenic variants and variants of unknown significance in EO cases when only gastrointestinal CSG were considered (OR 2.25; 95% CI: 1.01-5.06, p value = 0.04). Four EO cases stood out: two with POLE/POLD1 variants in the key exonuclease domain, one with a BMPR1A duplication and one with an EPCAM deletion. Additional germline variants should be considered in future screening recommendations, as they might influence cancer risk.

[Lynch syndrome: What is new?]

Lynch syndrome is a genetic condition defined by a germline mutation of an MMR (MisMatch Repair) gene leading to a defective DNA MMR system. Therefore, it is characterized by the predisposition to a spectrum of cancers, primarily colorectal cancer (CRC) and endometrial cancer (EC). Lynch syndrome-related CRC accounts for 3% of all CRC. Lynch syndrome also accounts for 2% of all EC. In case of Lynch syndrome, there is usually a familial history of cancer defined by the Amsterdam and Bethesda criteria. Diagnosis is made by tumor testing with (i) MMR immunohistochemistry and (ii) PCR for MSI (microsatellite instability), a genetic phenotype that characterizes these tumors. MSI can also be detected in sporadic tumors, through epigenetic events inactivating the MMR system. Progress in diagnosis and molecular biology has allowed for better identification of Lynch patients but also other rare genetic syndromes. MSI tumors can now benefit from new treatments such as immunotherapy which underlines the importance of their diagnosis. Finally, patients with Lynch syndrome as well as their relatives, undergo specific surveillance in order to prevent development of other cancers. This review will summarize the different aspects of Lynch syndrome and also focus on recent progress on the topic.

Comparison of anal cancer screening strategies including standard anoscopy, anal cytology, and HPV genotyping in HIV-positive men who have sex with men

BACKGROUND

There is no consensus on screening strategy of high-grade intraepithelial neoplasia (HGAIN). Guidelines range from clinical examination with digital anorectal examination followed by standard anoscopy (SA), to anal cytology (Pap)+/- HPV genotyping. We compared screening strategy yields based on Pap, SA, and HPV-16 genotyping alone or in combination in HIV-MSM.

METHODS

Pap, SA, and HPV-16 genotyping were performed in all HIV-MSM attending a first anal cancer screening consultation in Paris, France. High-resolution anoscopy, the gold standard to detect HGAIN, was performed in the case of HPV-16 positivity or abnormal cytology. Yield was defined as the number of patients with HGAIN relative to the total number of patients screened.

RESULTS

On 212 patients, the complete strategy (SA + Pap + HPV genotyping) yield (12.7%) was significantly higher than that of SA (3.3%, p < 0.001) and HPV-16 alone (6.6%, p < 0.05). Although none of the other strategies were significantly different from the complete strategy, Pap + HPV-16 and Pap + SA had closer yields (about 11%), with OR = 0.83 (95% CI [0.44;1.57]) and 0.87 (95% CI [0.46;1.64]), respectively.

CONCLUSIONS

Pap combined with HPV-16 genotyping or SA tended towards higher yields compared to Pap alone, and closer to that of the complete strategy.

Advances in management of adjuvant chemotherapy in rectal cancer: Consequences for clinical practice

More than half the patients with rectal cancer present with locally advanced rectal disease at diagnosis with a high risk of recurrence. Preoperative chemoradiotherapy and standardized radical surgery with total mesorectal excision have been established as the 'gold standard' for treating these patients. Pathological staging using the ypTNM classification system to decide on adjuvant chemotherapy (ACT) is widely used in clinical practice, but the delivery of ACT is still controversial, as many discrepancies persist in the conclusions of different trials, due to heterogeneity of the inclusion criteria between studies, lack of statistical power, and variations in preoperative and adjuvant regimens. In 2014, a meta-analysis of four randomized phase-III trials (EORTC 22921, I-CNR-RT, PROCTOR-SCRIPT, CHRONICLE) failed to demonstrate any statistical efficacy of fluorouracil (5FU)-based ACT. Three recent randomized trials aimed to compare 5FU with 5FU plus oxaliplatin-based chemotherapy. Two of them (ADORE, CAO/ARO/AIO-04) appeared to find a disease-free survival benefit for patients treated with the combination therapy. Thus, while awaiting new data, it can be said that, as of 2015, patients with yp stage I tumors or histological complete response derived no benefit from adjuvant therapy. On the other hand, the FOLFOX chemotherapy regimen should be proposed for yp stage III patients, and may be considered for yp stage II tumors in fit patients with high-risk factors. Nevertheless, well-designed and sufficiently powered clinical trials dedicated to adjuvant treatments for rectal cancer remain justified in future to achieve a high level of proof in keeping with evidence-based medical standards.

[Sclerosing injections of oesophageal varices. Analysis of 247 cases treated between 1964 and 1977 (author's transl)]

The authors analyse 247 cases of haemorrhagic oesophageal varices treated using sclerosing injections of Quinine-Urea between 1964 and 1977. Portal hypertension as a result of intrahepatic block accounted for 83% of the patients (alcoholic cirrhosis 65%, meta-icteric 12%) and cavernomas 11%. Sclerosing injections were used in patients refused by surgeons (85%) or after the failure of surgery (15%). Only 11 cases were treated during the period of active haemorrhage, and the others during the following weeks. Tolerance of treatment so long as all safety factors were employed routinely in order to deal with any possible haemorrhagic complications. Deaths due to the method totalled 2.8%, including those due to worsening of the underlying disease. Overall results were of 69% survival of more than one year, 40% at more than 3 years and 24% at more than five years. For alcoholic cirrhosis, these figures were respectively 62, 30 and 18%. The prognosis in cases of cavernoma was much better; 80% survival at more than 5 years.