Colonoscopy and sigmoidoscopy provide protection against colorectal cancer, but the magnitude and duration of protection, particularly against cancer of the proximal colon, remain uncertain.
We ...examined the association of the use of lower endoscopy (updated biennially from 1988 through 2008) with colorectal-cancer incidence (through June 2010) and colorectal-cancer mortality (through June 2012) among participants in the Nurses' Health Study and the Health Professionals Follow-up Study.
Among 88,902 participants followed over a period of 22 years, we documented 1815 incident colorectal cancers and 474 deaths from colorectal cancer. With endoscopy as compared with no endoscopy, multivariate hazard ratios for colorectal cancer were 0.57 (95% confidence interval CI, 0.45 to 0.72) after polypectomy, 0.60 (95% CI, 0.53 to 0.68) after negative sigmoidoscopy, and 0.44 (95% CI, 0.38 to 0.52) after negative colonoscopy. Negative colonoscopy was associated with a reduced incidence of proximal colon cancer (multivariate hazard ratio, 0.73; 95% CI, 0.57 to 0.92). Multivariate hazard ratios for death from colorectal cancer were 0.59 (95% CI, 0.45 to 0.76) after screening sigmoidoscopy and 0.32 (95% CI, 0.24 to 0.45) after screening colonoscopy. Reduced mortality from proximal colon cancer was observed after screening colonoscopy (multivariate hazard ratio, 0.47; 95% CI, 0.29 to 0.76) but not after sigmoidoscopy. As compared with colorectal cancers diagnosed in patients more than 5 years after colonoscopy or without any prior endoscopy, those diagnosed in patients within 5 years after colonoscopy were more likely to be characterized by the CpG island methylator phenotype (CIMP) (multivariate odds ratio, 2.19; 95% CI, 1.14 to 4.21) and microsatellite instability (multivariate odds ratio, 2.10; 95% CI, 1.10 to 4.02).
Colonoscopy and sigmoidoscopy were associated with a reduced incidence of cancer of the distal colorectum; colonoscopy was also associated with a modest reduction in the incidence of proximal colon cancer. Screening colonoscopy and sigmoidoscopy were associated with reduced colorectal-cancer mortality; only colonoscopy was associated with reduced mortality from proximal colon cancer. Colorectal cancer diagnosed within 5 years after colonoscopy was more likely than cancer diagnosed after that period or without prior endoscopy to have CIMP and microsatellite instability. (Funded by the National Institutes of Health and others.).
Gaps in colonoscopy skills among endoscopists, primarily due to experience, have been identified, and solutions are critically needed. Hence, the development of a real-time robust detection system ...for colorectal neoplasms is considered to significantly reduce the risk of missed lesions during colonoscopy. Here, we develop an artificial intelligence (AI) system that automatically detects early signs of colorectal cancer during colonoscopy; the AI system shows the sensitivity and specificity are 97.3% (95% confidence interval CI = 95.9%-98.4%) and 99.0% (95% CI = 98.6%-99.2%), respectively, and the area under the curve is 0.975 (95% CI = 0.964-0.986) in the validation set. Moreover, the sensitivities are 98.0% (95% CI = 96.6%-98.8%) in the polypoid subgroup and 93.7% (95% CI = 87.6%-96.9%) in the non-polypoid subgroup; To accelerate the detection, tensor metrics in the trained model was decomposed, and the system can predict cancerous regions 21.9 ms/image on average. These findings suggest that the system is sufficient to support endoscopists in the high detection against non-polypoid lesions, which are frequently missed by optical colonoscopy. This AI system can alert endoscopists in real-time to avoid missing abnormalities such as non-polypoid polyps during colonoscopy, improving the early detection of this disease.
Thyroid dysfunction (TD) induced by immune checkpoint inhibitors is not sufficiently understood. The purpose of this retrospective observational study was to identify risk factors and the clinical ...course of TD induced by nivolumab. Patients with advanced solid tumors who were treated with nivolumab from March 2009 through to March 2016 at the National Cancer Center Hospital (Tokyo, Japan) were included. Thyroid function and antithyroid Abs from serum samples among all patients were evaluated at baseline and during nivolumab treatment. Overt hypothyroidism was defined as low serum‐free T4 together with elevated thyroid‐stimulating hormone (TSH) >10 μIU/mL. Thyrotoxicosis was defined as low TSH with elevated free T4 and/or free T3. We defined thyroid autoimmunity as the presence of antithyroid Abs at baseline, including antithyroid peroxidase Abs and antithyroglobulin Abs (TgAb). Twenty‐three (14%) of a total of 168 patients developed TD, including 17 cases of hypothyroidism and 20 of thyrotoxicosis. Thyrotoxicosis followed by hypothyroidism occurred in 14 cases. Fourteen of 35 patients (40%) with thyroid autoimmunity developed TD vs 9 of 133 (7%) without (odds ratio 9.19; 95% confidence interval CI, 3.53‐23.9). In multivariate analysis, elevated TSH and TgAb at baseline were significantly associated with the development of TD, with odds ratio of 7.36 (95% CI, 1.66‐32.7) and 26.5 (95% CI, 8.18‐85.8), respectively. Association between TD and elevated antithyroid peroxidase Abs at baseline was not significant. These results suggest that patients with pre‐existing TgAb and elevated TSH at baseline are at high risk of TD.
Thyroid dysfunction induced by immune checkpoint inhibitors is not sufficiently understood. This retrospective observational study revealed that pre‐existing antithyroglobulin Abs and elevated thyroid‐stimulating hormone before nivolumab treatment are risk factors for the development of thyroid dysfunction induced by nivolumab.
BRAF mutation in colorectal cancer is associated with microsatellite instability (MSI) through its relationship with high-level CpG island methylator phenotype (CIMP) and MLH1 promoter methylation. ...MSI and BRAF mutation analyses are routinely used for familial cancer risk assessment. To clarify clinical outcome associations of combined MSI/BRAF subgroups, we investigated survival in 1253 rectal and colon cancer patients within the Nurses' Health Study and Health Professionals Follow-up Study with available data on clinical and other molecular features, including CIMP, LINE-1 hypomethylation, and KRAS and PIK3CA mutations. Compared with the majority subtype of microsatellite stable (MSS)/BRAF-wild-type, MSS/BRAF-mutant, MSI-high/BRAF-mutant, and MSI-high/BRAF-wild-type subtypes showed multivariable colorectal cancer-specific mortality hazard ratios of 1.60 (95% confidence interval CI =1.12 to 2.28; P = .009), 0.48 (95% CI = 0.27 to 0.87; P = .02), and 0.25 (95% CI = 0.12 to 0.52; P < .001), respectively. No evidence existed for a differential prognostic role of BRAF mutation by MSI status (P(interaction) > .50). Combined BRAF/MSI status in colorectal cancer is a tumor molecular biomarker for prognosic risk stratification.
Colorectal cancer is typically classified into proximal colon, distal colon and rectal cancer. Tumour genetic and epigenetic features differ by tumour location. Considering a possible role of bowel ...contents (including microbiome) in carcinogenesis, this study hypothesised that tumour molecular features might gradually change along bowel subsites, rather than change abruptly at splenic flexure.
Utilising 1443 colorectal cancers in two US nationwide prospective cohort studies, the frequencies of molecular features (CpG island methylator phenotype (CIMP), microsatellite instability (MSI), LINE-1 methylation and BRAF, KRAS and PIK3CA mutations) were examined along bowel subsites (rectum, rectosigmoid junction, sigmoid, descending colon, splenic flexure, transverse colon, hepatic flexure, ascending colon and caecum). The linearity and non-linearity of molecular relations along subsites were statistically tested by multivariate logistic or linear regression analysis.
The frequencies of CIMP-high, MSI-high and BRAF mutations gradually increased from the rectum (<2.3%) to ascending colon (36-40%), followed by falls in the caecum (12-22%). By linearity tests, these molecular relations were significantly linear from rectum to ascending colon (p<0.0001), and there was little evidence of non-linearity (p>0.09). Caecal cancers exhibited the highest frequency of KRAS mutations (52% vs 27-35% in other sites; p<0.0001).
The frequencies of CIMP-high, MSI-high and BRAF mutations in cancer increased gradually along colorectum subsites from the rectum to ascending colon. These novel data challenge the common conception of discrete molecular features of proximal versus distal colorectal cancers, and have a substantial impact on clinical, translational and epidemiology research, which has typically been performed with the dichotomous classification of proximal versus distal tumours.
Regular use of aspirin after a diagnosis of colon cancer has been associated with a superior clinical outcome. Experimental evidence suggests that inhibition of prostaglandin-endoperoxide synthase 2 ...(PTGS2) (also known as cyclooxygenase-2) by aspirin down-regulates phosphatidylinositol 3-kinase (PI3K) signaling activity. We hypothesized that the effect of aspirin on survival and prognosis in patients with cancers characterized by mutated PIK3CA (the phosphatidylinositol-4,5-bisphosphonate 3-kinase, catalytic subunit alpha polypeptide gene) might differ from the effect among those with wild-type PIK3CA cancers.
We obtained data on 964 patients with rectal or colon cancer from the Nurses' Health Study and the Health Professionals Follow-up Study, including data on aspirin use after diagnosis and the presence or absence of PIK3CA mutation. We used a Cox proportional-hazards model to compute the multivariate hazard ratio for death. We examined tumor markers, including PTGS2, phosphorylated AKT, KRAS, BRAF, microsatellite instability, CpG island methylator phenotype, and methylation of long interspersed nucleotide element 1.
Among patients with mutated-PIK3CA colorectal cancers, regular use of aspirin after diagnosis was associated with superior colorectal cancer-specific survival (multivariate hazard ratio for cancer-related death, 0.18; 95% confidence interval CI, 0.06 to 0.61; P<0.001 by the log-rank test) and overall survival (multivariate hazard ratio for death from any cause, 0.54; 95% CI, 0.31 to 0.94; P=0.01 by the log-rank test). In contrast, among patients with wild-type PIK3CA, regular use of aspirin after diagnosis was not associated with colorectal cancer-specific survival (multivariate hazard ratio, 0.96; 95% CI, 0.69 to 1.32; P=0.76 by the log-rank test; P=0.009 for interaction between aspirin and PIK3CA variables) or overall survival (multivariate hazard ratio, 0.94; 95% CI, 0.75 to 1.17; P=0.96 by the log-rank test; P=0.07 for interaction).
Regular use of aspirin after diagnosis was associated with longer survival among patients with mutated-PIK3CA colorectal cancer, but not among patients with wild-type PIK3CA cancer. The findings from this molecular pathological epidemiology study suggest that the PIK3CA mutation in colorectal cancer may serve as a predictive molecular biomarker for adjuvant aspirin therapy. (Funded by The National Institutes of Health and others.).
Thymic carcinoma (TC) is a rare cancer with a poor prognosis and limited treatment options, especially after relapse.
In this open-label, two-stage, multicentre, single-arm and phase II trial, the ...main eligibility criteria were unresectable or recurrent TC, an Eastern Cooperative Oncology Group–performance status of 0 or 1, progression after at least one chemo(radio)therapy and no history of autoimmune disease. Nivolumab was administered at a dose of 3 mg/kg every 2 weeks. The primary end-point was response rate (RR) as evaluated by central review using Response Evaluation Criteria In Solid Tumours (RECIST), version 1.1. The planned sample size was 15 for each stage, with a threshold RR of 5%, an expected RR of 20%, one-sided alpha of 5% and power of 80%.
Between July 1 and August 16 2016, 15 patients were accrued in the first stage. Response was assessable in all patients, and 13 had squamous histology. Median follow-up time was 14.1 months (range: 2.4–17.5). The median number of nivolumab received was eight (range: 3–33). RR was 0% (95% confidential interval CI: 0–21.8). Eleven patients had stable disease (SD) including five patients with SD for 24 or more weeks. Median progression-free survival was 3.8 months (95% CI: 1.9–7.0). Two patients experienced immune-related serious adverse events (grade III aspartate aminotransferase (AST) increase and grade II adrenal insufficiency). Because the early termination criteria (less than one responder) were fulfilled during the first stage, the patient accrual was terminated.
Despite the small number of patients, nivolumab was unable to produce tumour shrinkage by RECIST in previously treated unresectable or recurrent TC.
•Thymic carcinoma (TC) is a rare cancer with a poor prognosis and limited treatment options.•This is the first phase II trial of nivolumab for pretreated unresectable or recurrent TC.•Nivolumab produced no responders among the 15 patients accrued during the first stage.•Only two patients developed serious immune-related adverse events, both of which were resolved.•However, the disease control rate of 73% suggested some clinical benefit of nivolumab in TC.
Cause of death (COD) information taken from death certificates is often inaccurate and incomplete. However, the accuracy of Underlying CODs (UCODs) recorded on death certificates has not been ...comprehensively described when multiple diseases are present.
A total of 450 consecutive autopsies performed at a geriatric hospital in Japan between February 2000 and August 2002 were studied. We evaluated the concordance rate, sensitivity, and specificity of major UCODs (cancer, heart disease, and pneumonia) reported on death certificates compared with a reference standard of pathologist assessment based on autopsy data and clinical records. Logistic regression analysis was performed to assess the effect of sex, age, comorbidity, and UCODs on misclassification.
The concordance rate was relatively high for cancer (81%) but low for heart disease (55%) and pneumonia (9%). The overall concordance rate was 48%. Sex and comorbidity did not affect UCOD misclassification rates, which tended to increase with patient age, although the association with age was also not significant. The strongest factor for misclassification was UCODs (P < 0.0001). Sensitivity and specificity for cancer were very high (80% and 96%, respectively), but sensitivity for heart disease and pneumonia was 60% and 46%, respectively. Specificity for each UCOD was more than 85%.
Researchers should be aware of the accuracy of COD data from death certificates used as research resources, especially for cases of elderly patients with pneumonia.
Background:
Chemotherapy-induced peripheral neuropathy can occur in the right and left hand. Studies on prevention treatments for chemotherapy-induced peripheral neuropathy have largely adopted ...either self-controlled designs or parallel designs to compare two preventive treatments. When three treatment options (two experimental treatments and a control treatment) are available, both designs can be extended. However, no clinical trials have adopted a self-controlled design to compare three prevention treatments for chemotherapy-induced peripheral neuropathy. The incomplete block crossover design for more than two treatments can be extended to compare three treatments in the self-controlled design. In simple extension, some of the participants receive two experimental treatments in both hands; however, it may be difficult to administer different experimental treatments in both hands for practical reasons, such as a concern for the different types of unexpected adverse events. This study proposes a design and analysis method appropriate for the situation where only one experimental treatment is provided to each participant.
Methods:
We assume clinical trials to compare each of the two experimental treatments (E1 and E2) with the control treatment (C) and between two experimental treatments only when both experimental treatments are superior to the control treatment. We propose a self-controlled design, which equally randomizes to four arms to adjust for the dominant hand effect: Arm 1: E1 for right hand, C for left hand; Arm 2: C for right hand, E1 for left hand; Arm 3: E2 for right hand, C for left hand; and Arm 4: C for right hand, E2 for left hand. We compare operating characteristics of the proposed design with the three-arm parallel design in which the same treatment is performed in both hands by participants. We also assess three proposed analysis methods for comparisons between experimental treatments in the self-controlled design under several conditions of correlations between right and left hands using simulation studies.
Results:
The simulation studies showed that the proposed design was more powerful than the three-arm parallel design when correlation was 0.3 or higher. For comparisons between experimental treatments, the methods based on the regression model, including the outcome of hands with C as a covariate, had the highest power under modest to high correlation among the analysis methods in the self-controlled design.
Conclusion:
The proposed design can improve the power for comparing between two experimental treatments and the control treatment. Our design is useful in situations where it is undesirable for participants to receive different experimental treatments in both hands for practical reasons.