Deletion of first noncoding exon in ANKRD11 leads to KBG syndrome

Phenotypic features of KBG syndrome include craniofacial anomalies, short stature, cognitive disability and behavioral findings. The syndrome is caused by heterozygous pathogenic single nucleotide variants and indels in ANKRD11, or a heterozygous deletion of 16q24.3 that includes ANKRD11. We performed genome sequencing on a patient with clinical manifestations of KBG syndrome including distinct craniofacial features as well as a history of mild intellectual disability and attention-deficit hyperactivity disorder. This led to the identification of a 43 kb intragenic deletion of ANKRD11 affecting the first noncoding exon while leaving the coding regions intact. Review of the literature shows that this is the smallest 5' deletion affecting only the noncoding exons of ANKRD11. Real-time polymerase chain reaction demonstrated that the copy number variant was not present in either of the proband's parents, suggesting it occurred de novo. RNA expression analysis demonstrated significantly decreased transcript abundance compared to controls. This provides new evidence for haploinsufficiency as a mechanism of disease in KBG syndrome.

H4C5 missense variant leads to a neurodevelopmental phenotype overlapping with Angelman syndrome

Recurrent de novo missense variants in H4 histone genes have recently been associated with a novel neurodevelopmental syndrome that is characterized by intellectual disability and developmental delay as well as more variable findings that include short stature, microcephaly, and facial dysmorphisms. A 4-year-old male with autism, developmental delay, microcephaly, and a happy demeanor underwent evaluation through the Undiagnosed Disease Network. He was clinically suspected to have Angelman syndrome; however, molecular testing was negative. Genome sequencing identified the H4 histone gene variant H4C5 NM_003545.4: c.295T>C, p.Tyr99His, which parental testing confirmed to be de novo. The variant met criteria for a likely pathogenic classification and is one of the seven known disease-causing missense variants in H4C5. A comparison of our proband's findings to the initial description of the H4-associated neurodevelopmental syndrome demonstrates that his phenotype closely matches the spectrum of those reported among the 29 affected individuals. As such, this report corroborates the delineation of neurodevelopmental syndrome caused by de novo missense H4 gene variants. Moreover, it suggests that cases of clinically suspected Angelman syndrome without molecular confirmation should undergo exome or genome sequencing, as novel neurodevelopmental syndromes with phenotypes overlapping with Angelman continue to be discovered.

Genome sequencing reveals novel noncoding variants in PLA2G6 and LMNB1 causing progressive neurologic disease

Neurodegenerative disorders and leukodystrophies are progressive neurologic conditions that can occur following the disruption of intricately coordinated patterns of gene expression. Exome sequencing has been adopted as an effective diagnostic tool for determining the underlying genetic etiology of Mendelian neurologic disorders, however genome sequencing offer advantages in its ability to identify and characterize copy number, structural, and sequence variants in noncoding regions. Genome sequencing from peripheral leukocytes was performed on two patients with progressive neurologic disease of unknown etiology following negative genetic investigations including exome sequencing. RNA sequencing from peripheral blood was performed to determine gene expression patterns in one of the patients. Potential causative variants were matched to the patients' clinical presentation. The first proband was found to be heterozygous for a likely pathogenic missense variant in PLA2G6 (c.386T>C; p.Leu129Pro) and have an additional deep intronic variant in PLA2G6 (c.2035-926G>A). RNA sequencing indicated this latter variant created a splice acceptor site leading to the incorporation of a pseudo-exon introducing a premature termination codon. The second proband was heterozygous for a 261 kb deletion upstream of LMNB1 that included an enhancer region. Previous reports of copy number variants spanning this region of cis-acting regulatory elements corroborated its pathogenicity. When combined with clinical presentations, these findings led to a definitive diagnosis of autosomal recessive infantile neuroaxonal dystrophy and autosomal dominant adult-onset demyelinating leukodystrophy, respectively. In patients with progressive neurologic disease of unknown etiology, genome sequencing with the addition of RNA analysis where appropriate should be considered for the identification of causative noncoding pathogenic variants.

Impact of infectious complications on long-term survival following colorectal cancer surgery

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Background: Colorectal cancer surgery is associated with significant postoperative morbidity, which may have long-term implications on patient outcomes. We hypothesize that operative complications following surgery for colorectal cancer are associated with increased recurrence and worse survival. Methods: Using a prospectively maintained database, we reviewed patients with colorectal cancer that underwent a curative resection from 2008 to 2015. Patients were categorized by presence of any complication within 90 days from surgery and by type of complication, infectious and non-infectious. We compared clinical, pathological, and perioperative data using t-test, chi-squared test, and ANOVA. We compared overall (OS) and recurrence free survival (RFS) using Kaplan Meier and log-rank test. Multivariable Cox regression was used to compare mortality and recurrence. Results: Two hundred and twenty-nine patients underwent 104 colon and 125 rectal cancer resections (20 pelvic exenterations, 83 low anterior and 17 abdominoperineal resections) were followed for a median of 23 months. Fifty percent were completed minimally invasively. Postoperative complications occurred in 52%; 19% had a major complication (Clavien-Dindo 3-4). Postoperative complications were more likely to occur in open (61% vs. 38%, p < 0.01) and rectal operations (63% vs. 42%, p = 0.02). On multivariable analysis, OS and RFS were not statistically different in patients with complications. Patients with infectious complications had worse 3-year survival when compared to patients with non-infectious complications and without complications (58%,69%,76%, p = 0.04). Recurrence at 3 years was also significantly different among the three groups (p = 0.03). Infectious complications remained associated with worse overall survival (HR 1.8; 95% CI 1.02,3.26) and recurrence free survival (HR 1.9; 95% CI 1.06,3.39) after adjusting for patient, tumor, and perioperative data. Conclusions: Infectious complications following colorectal cancer surgery are associated with worse OS and RFS independent of tumor stage, type of surgery, and technique. Current research is ongoing to explore possible etiologies of this association.

Perioperative outcomes for robotic total mesorectal excision after preoperative chemoradiation for rectal cancer

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Background: Laparoscopic total mesorectal excision (TME) after preoperative chemoradiation therapy (P-CRT) for mid to low rectal cancer was shown to be safe and feasible by a recent randomized trial (COREAN trial). However, the safety and short-term efficacy for robotic assisted laparoscopic TME has not been demonstrated. This study is a review of the perioperative outcomes of robotic TME after P-CRT for mid to low rectal cancer at our institution. Methods: All patients that underwent robotic TME after P-CRT for rectal cancer were retrospectively reviewed in our prospectively maintained, IRB-approved surgical oncology database. All relevant demographic, clinical, operative, pathology and perioperative data were analyzed. These were compared to the COREAN trial results. Results: From 2010 to 2014, 42 patients underwent robotic TME for rectal cancer after P-CRT. Mean patient age was 60+/-13. Robotic low anterior resections (R-LAR) were performed in 69% and 31% had a robotic abdominoperineal resection (R-APR). A majority were obese patients as 74% had a BMI ≥ 25, and 50% had an ASA ≥ 3. Conversion to open rate was 9.5% (n = 4) but 3 of these were within the first 8 cases. Median estimated blood loss was 105 ml (50-400 ml). The 30-day major complication rate (Clavien III-IV) was 11.9% (n = 5) and 90-day rate was 14.2% (n = 6). One patient (2.4%) had an anastomotic leak. There were no mortalities within 90-days from operation. Median length of stay was 7 days (6-12 days). Pathological complete response was 19% while 24% had no response. The average number of lymph nodes harvested was 14.2+/-9.5. The circumferential resection margin was negative in 95.2% (n = 40) of patients. Conclusions: As compared to laparoscopic TME patients in the COREAN trial, the robotic patients in our series were more obese and had a higher ASA classification. Our conversion rate was slightly higher, but this was related to the learning curve. All other short-term outcomes were similar. It appears that robotic TME is safe and feasible after P-CRT even among a more obese and higher risk population than previously reported in large series.

Impact of weight change during neoadjuvant chemotherapy on pathologic response in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an uncommon but aggressive subtype of breast cancer. Obesity has been associated with an increased risk of breast cancer and worse prognosis. Some studies suggest that obese patients are less likely to achieve pathologic complete response (pCR) to neoadjuvant chemotherapy (NCT) and experience worse overall survival. Ki-67 is a proliferation marker that correlates with tumor aggressiveness. The goal of this study was to examine the impact of weight change during NCT for TNBC on pathologic response and Ki-67 reduction. Retrospective review identified 173 TNBC patients treated between 2004 and 2011. Data were collected on patient demographics, pre- and post-NCT body mass index (BMI), Ki-67, and pCR. Data analysis was performed using the two-tailed Student's t-test, analysis of variance (ANOVA), and Fisher's exact test. Sixty-six patients met final study criteria. Forty-three patients lost weight during chemotherapy and 23 gained weight. Patients in the weight gain group were significantly younger (P = 0.0013). There was no significant difference between the two groups in terms of Ki-67 reduction (P = 0.98) or pCR (P = 0.58). When patients were separated into normal weight (BMI<25 kg/m(2) ), overweight (BMI ≥ 25 and <30 kg/m(2) ), and obese (BMI ≥ 30 kg/m(2) ), there was no significant difference in Ki-67 among those groups either before or after NCT. The degree of obesity did not have a significant impact on Ki-67 reduction. Weight change during NCT does not appear to correlate with Ki-67 change or achieving pCR in TNBC. This may reflect the nature of this subtype of breast cancer that is less responsive to the hormonal effects that adipose tissue exerts on cancer cell proliferation.

Occupational transmission of Mycobacterium tuberculosis to health care workers in a university hospital in Lima, Peru

From November 1996 through March 1997, presumptive active pulmonary tuberculosis (TB) was detected in 44 health care workers (HCWs) at a university hospital in Lima, Peru. To further assess the magnitude of the outbreak and determine risk factors for occupational Mycobacterium tuberculosis transmission, we identified HCWs in whom active pulmonary TB was diagnosed from January 1994 through January 1998, calculated rates by year and hospital work area, and conducted a tuberculin skin test (TST) survey. Thirty-six HCWs had confirmed active pulmonary TB. The rate of TB was significantly higher among the 171 HCWs employed in the laboratory than among HCWs employed in all other areas. In multivariate analysis, the only independent risk factor for HCW M. tuberculosis infection in HWCs employed in the laboratory was the use of common staff areas. Very high rates of active pulmonary TB were detected among HCWs at this hospital, and occupational acquisition in the laboratory was associated with HCW-to-HCW transmission.