High risk of rectal cancer and of metachronous colorectal cancer in probands of families fulfilling the Amsterdam criteria.

OBJECTIVE: To investigate the risk of metachronous colorectal cancer (CRC), its impact on survival, and the risk of rectal cancer in a cohort of probands meeting the Amsterdam criteria. BACKGROUND: Several determinants of decision-making for the management of CRC in patients with a putative diagnosis of Lynch syndrome are scarcely defined, and many of them undergo segmental bowel resection instead of the advised total colectomy. METHODS: A retrospective cohort study was conducted on 65 probands of the Amsterdam-positive families who had surgery for primary CRC and at least 5-year surveillance thereafter. The rates of metachronous CRC and of rectal cancer were evaluated, together with their association with preoperatively available clinical predictors. Differences in overall survival between patients with and without metachronous CRC were evaluated using a time-dependent Cox model. RESULTS: Seventeen patients (26.2%) had metachronous CRC. No clinical feature was associated with an increased risk of its development. The risk of death in patients with metachronous CRC was 6-fold increased. Neither a 2-year interval endoscopic surveillance after surgery, nor total colectomy was associated with a significant reduction in metachronous CRC. Eighteen patients (23.7%) had rectal cancer at first presentation, 5 patients of the remainder (10.6%) developed rectal cancer after primary colon resection. Two patients undergoing total colectomy developed a metachronous rectal cancer (18.2%). A first-degree family history of rectal cancer was associated with an increased risk of rectal cancer. CONCLUSIONS: Probands of families fulfilling the Amsterdam criteria carry a high risk of rectal cancer and of metachronous CRC. Total proctocolectomy, or total colectomy and a 1-year interval of proctoscopic surveillance should be advised when a high risk of rectal cancer can be predicted.

Sex estimation of the subadult ilium prior to acetabular fusion.

Previous studies evaluating sexual dimorphism in subadult pelvic features present variable, and at times conflicting, conclusions. As a result, there is yet to be a consensus on whether the subadult pelvis can be used in sex estimation methods. This study aims to assess the forensic utility of ilium shape and greater sciatic notch morphology in sexing subadult pelves prior to acetabular fusion. A sample of 397 modern U.S. individuals with unfused acetabula (i.e., tri-radiate cartilages) aged birth to 14 years was queried from a larger sample of postmortem computed tomography scans. Elliptical Fourier analyses were performed on ilium and greater sciatic notch outlines and resultant PCs were evaluated for significant effects of sex and age. Greater sciatic notch metrics were also collected. Stepwise linear discriminant function analyses with leave-one-out cross-validation were performed on the PCs and metric variables. Analyses were performed on pooled samples, on age-specific cohort samples, and on samples that iteratively removed the youngest one-year cohort. Cross-validated correct classification rates ranged from 57% to 65% and no patterns were observed to support an appearance and/or consistent expression of sexually diagnostic traits. Based on the results, sex estimation using these features is not recommended in pelvic remains prior to acetabular fusion, although the sample sizes of individuals over 5 years of age were limited in this study. Future studies should focus on the sexually diagnostic ability of pelvic traits in subadult samples post-fusion of the acetabulum.

Loupe magnification reduces postoperative hypocalcemia after total thyroidectomy.

We aimed to evaluate the impact of loupe magnification (LM) on incidental parathyroid gland removal (from pathology reports), hypocalcemia, and recurrent laryngeal nerve (RLN) injury after total thyroidectomy and answer the question of whether this tool should be always recommended for patient's safety. Between January 2005 and December 2008, 126 patients underwent total thyroidectomy with routine use of 2.5 x galilean loupes; their charts were compared with data on 118 patients operated on between January 1997 and December 2000 without LM (two different equally skilled surgical teams operating in the two periods). LM decreased the rate of inadvertent parathyroid glands removal (3.8 vs 7.8% of total parathyroid glands; P = 0.01), as well as of biochemical (20.6 vs 33.9%; P = 0.028) and clinical (12.7 vs 33%; P = 0.0003) hypocalcemia after thyroidectomy. All cases (16 of 16) of symptomatic hypocalcaemia in the LM group proved to be associated with parathyroidectomy vs 76.9 per cent (30 of 39) without LM (P = 0.046). A trend toward decreased RLN injury rate, although statistically insignificant, was reported, being unilateral transient, unilateral permanent, and bilateral transient palsy rates 6.8, 2.5, and 1.7 per cent, respectively, without LM vs 4.8, 2.4, and 0.8 per cent, respectively, with LM (P = 0.69; P = 1, and P = 0.61, respectively). Our results do support the routine use of LM during total thyroidectomy.

The importance of processing procedures and threshold values in CT scan segmentation of skeletal elements: An example using the immature os coxa.

As the accessibility and utility of virtual databases of skeletal collections continues to grow, the impact that scan processing procedures has on the accuracy of data obtained from virtual databases remains relatively unknown. This study quantifies the intra- and inter-observer error generated from varying computed tomography (CT) scan processing protocols, including re-segmentation, incrementally varying thresholding value, and data collectors' selection of the threshold value on a set of virtual subadult pelves. Four observers segmented the subadult ossa coxarum from postmortem CT scans of the fully-fleshed bodies of eleven individuals of varying ages. Segmentation protocol was set, with the exception of each observer selecting their own thresholding value for each scan. The resulting smoothed pelvic surfaces were then compared using deviation analyses. Root mean square error (RMSE), average distance deviation, and maximum deviation distances demonstrated that thresholding values of ∼50 HU (Hounsfield units) are easily tolerated, the surfaces generated are robust to error, and threshold value selection does not systematically vary with user experience. The importance of consistent methodology during segmentation protocol is highlighted here, especially with regards to consistency in both selected thresholding value as well as smoothing protocol, as these variables can affect subsequent measurements of the resultant surfaces.

Modifiable risk factors in colorectal surgery: central role of surgeon's volume.

BACKGROUND: Our objective was to inform the ongoing debate regarding selective referral of colorectal cancer patients to high-volume surgeons in order to improve outcomes. PATIENTS AND METHOD: We evaluated data on patients treated by colorectal-dedicated surgeons (first study-group) and non specialized surgeons (second study-group). Particular attention has been paid to patients selection in order to collect two study-groups with similar demographic and clinical characteristics, differing only as regards providers' surgical experience in the colorectal field. We focused on postoperative mortality and 5-year overall and cancer-specific survival. We also analyzed resection rates of the primary tumor and colostomy rates for patients with stage I to III rectal cancer, and use of (neo)adjuvant (chemo)radiation therapy for patients with stage II-III rectal cancer by surgeon's volume. RESULTS: The analysis of these 2 study-groups shows better results for patients treated by colorectal-trained surgeons (high-volume surgeons) for each parameter taken into account: lower postoperative mortality (OR 0.32; 95% CI:0.7-0.1; p = 0.04), increased 5-year overall and cancer specific survival (rising from 41.2% and 46.4% to 56% and 61.2% respectively; OR 1.8; 95% CI: 1.3-2.6; p < 0.005). Patient treated by non specialized surgeons are more likely to receive a permanent colostomy (abdominoperineal resection: APR) (OR 5.9; 95% CI: 3.3-10.7) and to undergo a non-resective procedure (OR 4.8; 95% CI: 1.9-12)(p < 0.005). No difference was found between the 2 study-groups in the use of (neo)adjuvant (chemo)radiation therapy for patients with stage II-III rectal cancer. CONCLUSIONS: Our analysis suggests that surgeon's volume does impact on outcomes for patients undergoing surgery due to colorectal cancer.