Christian Buchli

Objective: To assess the performance of an algorithm for automated grading of surgery-related adverse events (AEs) according to Clavien-Dindo (C-D) classification. Background: Surgery-related AEs are common, lead to increased patient morbidity, and raise health care costs. Resource-intensive manual chart review is still standard, and, to our knowledge, algorithms using electronic health record (EHR) data to grade AEs according to C-D classification have not been explored. Methods: The algorithm was developed in a research database containing all EHR data of Karolinska University Hospital Stockholm and returns a C-D grade for each AE within 30 days. This raw score was used to grade the postoperative recovery of 1379 elective colorectal procedures according to C-D classification and Comprehensive Complication Index. Agreement with manual annotation of colorectal surgeon (gold standard) and research nurse (current practice) was assessed in a random sample of 399 procedures. Results: For the C-D classification, kappa was 0.77 (95% CI: 0.71 to 0.84) for algorithm versus surgeon and 0.74 (95% CI: 0.67 to 0.82) for algorithm versus nurse. The kappa value increased to 0.89 (95% CI: 0.84 to 0.95) after the correction of misclassified annotations by the surgeon. The intraclass correlation for Comprehensive Complication Index between algorithm and surgeon was 0.89 (95% CI: 0.87 to 0.91) after correction and 0.76 (95% CI: 0.71 to 0.80) for algorithm versus nurse. Conclusions: The performance of the algorithm motivates in our opinion implementation to real-time data under continuous scientific evaluation of the impact on AEs in different types of surgery. In the future, local EHR data could be used to enhance risk prediction with machine learning techniques.

Preoperative radiotherapy (RT) for non-metastatic rectal cancer reduces local recurrence rates but can cause pelvic insufficiency fractures. Despite the high morbidity from RT-induced skeletal injuries, predictive and preventive measures are lacking. How these injuries are reflected by bone biomarkers are largely unknown. The aim was to assess longitudinal changes in bone biomarkers and their relation to RT-related bone injuries in women with rectal cancer. This longitudinal cohort study includes 47 women with non-metastatic rectal cancer treated with surgery ± preoperative RT with or without chemotherapy. Sclerostin, bioactive sclerostin, C-terminal telopeptide cross-links of collagen type I (CTX), bone-specific alkaline phosphatase (BALP), and type I procollagen intact N-terminal propeptide (PINP) were measured at baseline, after RT, and 1 yr postoperatively. Pelvic magnetic resonance imaging was used for detection of skeletal injury. Sixteen of 36 (44%) irradiated women had radiation-induced bone injuries and were compared to 11 women (RT–) and 20 women (RT+) without bone injuries. Serum CTX, BALP, and PINP increased during the first year after RT in women with radiation-induced bone injuries. The difference in mean change of CTX (p=.037) and BALP (p=.042) was conferred by longitudinal regression analyses adjusted for serum estradiol. Serum sclerostin and bioactive sclerostin remained stable over time. Taken together, bone markers may be of interest for future research on fracture prediction or preventive measures in women susceptible to radiation-induced bone injury. Due to few measure points, the full pattern cannot be captured regarding the relation over time between bone biomarkers and skeletal injury from irradiation. Radiation therapy (RT) for rectal cancer before surgery reduces the risk of cancer recurrence, but can cause injuries to the pelvic bone. Despite the high morbidity from RT-caused skeletal injuries, predictive and preventive measures are lacking. How these bone injuries are reflected by bone biomarkers measured in serum is largely unknown. The aim of this study was to measure serum bone biomarkers and their relation to RT-related bone injuries in women with rectal cancer. The study group included 47 women with rectal cancer treated with surgery ± preoperative RT. Pelvic magnetic resonance imaging was used for detection of skeletal injury. The bone biomarkers sclerostin, bioactive sclerostin, C-terminal telopeptide cross-links of collagen type I (CTX), bone-specific alkaline phosphatase (BALP), and type I procollagen intact N-terminal propeptide (PINP) were measured at baseline, after RT, and 1 yr after surgery. Sixteen of 36 (44%) irradiated women had radiation-caused bone injuries and were compared to 31 women without bone injuries. Serum CTX, BALP, and PINP increased during the first year after RT in women with radiation-caused bone injuries. In summary, bone markers may be of interest for future research on fracture prediction or preventive measures in women prone to radiation-caused bone injury.