Timing of Admission to the Surgical Intensive Care Unit is Associated with in-Hospital Mortality

Purpose@#The relationship between the timing of admission (work-hours or after-hours) to the intensive care unit (ICU) and mortality among surgical ICU (SICU) patients is unclear. This study aimed to investigate whether admission to SICU during after-hours was associated with in-hospital mortality. @*Methods@#This retrospective cohort study was conducted in a tertiary academic hospital. The data of 571 patients who were admitted to the SICU and whose complete medical records were available were analyzed. Work-hours were defined as 07:00 to 19:00 Monday to Friday, during which the ICU was staffed with intensivists. After-hours were defined as any other time during which the SICU was not staffed with intensivists. The primary outcome measure was in-hospital mortality according to the time of admission (work-hours or after-hours) to the SICU. @*Results@#A total of 333 patients, were admitted to the SICU during work-hours, and 238 patients after-hours. Unplanned admissions (47.1% vs. 33.3%, p < 0.001), acute physiology and chronic health evaluation II score ≥ 25 (23.9% vs. 11.1%, p < 0.001), the need for ventilator support (34.0% vs. 17.4%, p < 0.001), and the use of vasopressors (50.0% vs. 33.3%, p < 0.001) were significantly higher in the after-hours group compared with the work-hours group. Multivariate analyses revealed that the timing of SICU admission was an independent predictor of in-hospital mortality (odds ratio, 2.526; 95% confidence interval, 1.010–6.320; p = 0.048). @*Conclusion@#This study showed that admission to the SICU during after-hours was associated with increased in-hospital mortality.

Management of Traumatic Duodenal Injuries: A Report from a Single-Center

Purpose@#Traumatic duodenal injury is uncommon and due to its difficult diagnosis and accessibility there is an increased risk of mortality and morbidity. @*Methods@#Electronic medical records of a single center were reviewed retrospectively from March 2008 to December 2020 and a total of 7 cases of traumatic duodenal injury were managed by surgical exploration. The site of duodenal perforation, injury mechanisms, operation method, and postoperative outcomes were assessed. @*Results@#The mean age was 55.72 years (range, 34-78), and there were 5 men in the study. The most common mechanism was in-car traffic accident (4 cases), and 1 case each of pedestrian accident, accident during work, and self-injured stab wound. The most common site of injury was between the 3rd and 4th portion (3 cases), followed by the bulb and 1st portion (2 cases), and 2nd portion (2 cases). Segmental resection of the duodenum and primary anastomosis was performed in the 3rd and 4th portion perforation. In cases of 1st and 2nd portion, injury was managed by primary repair or pylorus preserving pancreaticoduodenectomy. Complications developed in 4 patients, and the most common complication was a problem with the wound; wound seromas developed in 4 cases, entero-cutaneous fistula in 1, and biliary complications in 2 cases. Two patients suffered from intraperitoneal abscess or fluid collection managed by percutaneous drainage. The mean duration of hospital stay was 34 days, and postoperative mortality did not develop. @*Conclusion@#Favorable clinical outcomes were observed in patients with traumatic duodenal injury managed by various surgical approaches.

LASSO-Based Machine Learning Algorithm for Prediction of Lymph Node Metastasis in T1 Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The role of tumor-infiltrating lymphocytes (TILs) in predicting lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC) remains unclear. Furthermore, clinical utility of a machine learning–based approach has not been widely studied. @*Materials and Methods@#Immunohistochemistry for TILs against CD3, CD8, and forkhead box P3 in both center and invasive margin of the tumor were performed using surgically resected T1 CRC slides. Three hundred and sixteen patients were enrolled and categorized into training (n=221) and validation (n=95) sets via random sampling. Using clinicopathologic variables including TILs, the least absolute shrinkage and selection operator (LASSO) regression model was applied for variable selection and predictive signature building in the training set. The predictive accuracy of our model and the Japanese criteria were compared using area under the receiver operating characteristic (AUROC), net reclassification improvement (NRI)/integrated discrimination improvement (IDI), and decision curve analysis (DCA) in the validation set. @*Results@#LNM was detected in 29 (13.1%) and 12 (12.6%) patients in training and validation sets, respectively. Nine variables were selected and used to generate the LASSO model. Its performance was similar in training and validation sets (AUROC, 0.795 vs. 0.765; p=0.747). In the validation set, the LASSO model showed better outcomes in predicting LNM than Japanese criteria, as measured by AUROC (0.765 vs. 0.518, p=0.003) and NRI (0.447, p=0.039)/IDI (0.121, p=0.034). DCA showed positive net benefits in using our model. @*Conclusion@#Our LASSO model incorporating histopathologic parameters and TILs showed superior performance compared to conventional Japanese criteria in predicting LNM in patients with T1 CRC.

LASSO-Based Machine Learning Algorithm for Prediction of Lymph Node Metastasis in T1 Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The role of tumor-infiltrating lymphocytes (TILs) in predicting lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC) remains unclear. Furthermore, clinical utility of a machine learning–based approach has not been widely studied. @*Materials and Methods@#Immunohistochemistry for TILs against CD3, CD8, and forkhead box P3 in both center and invasive margin of the tumor were performed using surgically resected T1 CRC slides. Three hundred and sixteen patients were enrolled and categorized into training (n=221) and validation (n=95) sets via random sampling. Using clinicopathologic variables including TILs, the least absolute shrinkage and selection operator (LASSO) regression model was applied for variable selection and predictive signature building in the training set. The predictive accuracy of our model and the Japanese criteria were compared using area under the receiver operating characteristic (AUROC), net reclassification improvement (NRI)/integrated discrimination improvement (IDI), and decision curve analysis (DCA) in the validation set. @*Results@#LNM was detected in 29 (13.1%) and 12 (12.6%) patients in training and validation sets, respectively. Nine variables were selected and used to generate the LASSO model. Its performance was similar in training and validation sets (AUROC, 0.795 vs. 0.765; p=0.747). In the validation set, the LASSO model showed better outcomes in predicting LNM than Japanese criteria, as measured by AUROC (0.765 vs. 0.518, p=0.003) and NRI (0.447, p=0.039)/IDI (0.121, p=0.034). DCA showed positive net benefits in using our model. @*Conclusion@#Our LASSO model incorporating histopathologic parameters and TILs showed superior performance compared to conventional Japanese criteria in predicting LNM in patients with T1 CRC.

Whole Body Bone Scan for Detecting Missed Bone Injuries in Multiple Trauma Patients

PURPOSE: Patients with multiple traumas often experience multiple fractures that are missed or overlooked, despite the use of imaging, careful history taking, and physical examinations. This study aimed to evaluate the usefulness of whole body bone scan (WBBS) for detecting missed bone injuries in patients with multiple traumas. METHODS: We evaluated 30 patients with multiple traumas who underwent WBBS at single tertiary referral center between March 2008 and February 2016. We assessed the association of patient demographics with WBBS uptake as a binomial outcome variable. RESULTS: There were no significant differences in patient demographics by WBBS. The mean injury severity score did not differ by WBBS (18.1 in the WBBS-negative group vs. 18.4 in the WBBS-positive group), and duration from admission to the evaluation of the WBBS was similar (5.4 days in both groups). The most common uptake site in the WBBS was the ribs (n=7), followed by the tibia (n=3), skull (n=2), ankle (n=1), and sternum (n=1). None of the missed injuries required further treatment, such as manual reduction or surgery. CONCLUSION: WBBS was useful for detecting missed bone injuries in patients with multiple trauma.

Which patients with intestinal obstruction need surgery? The delta neutrophil index as an early predictive marker

PURPOSE: Predicting the need for surgical intervention among patients with intestinal obstruction is challenging. The delta neutrophil index (DNI) has been suggested as a useful marker of immature granulocytes, which indicate an infection or sepsis. In this study, we evaluated the impact of the DNI as an early predictor of operation among patients with intestinal obstruction. METHODS: A total of 171 patients who were diagnosed with postoperative intestinal obstruction were enrolled in this study. Medical records, including data for the initial CRP level, WBC count, and DNI were reviewed. Receiver operating characteristic (ROC) curves were generated to clarify the optimal DNI cutoff values for predicting an operation. RESULTS: Among the 171 patients, 38 (22.2%) needed surgical intervention. The areas under the initial CRP, WBC, and DNI ROC curves were 0.460, 0.449, and 0.543, respectively. The optimal cutoff value for predicting further surgical intervention according to the initial DNI level was 4.3%. The accuracy of the cutoff value was 74.9%, the sensitivity was 23.7%, and the specificity was 89.5% (positive predictive value, 23.7%; negative predictive value, 89.5%). In the multivariate analysis, initial DNI levels ≥ 4.3% were significantly associated with surgical intervention (odd ratio, 3.092; 95% confidence interval, 1.072–8.918; P = 0.037). CONCLUSION: The initial DNI level in patients with intestinal obstruction may be a useful predictor for determining the need for surgical intervention.

Multiple Myeloma Mimics Bone Metastasis From a Rectal Adenocarcinoma

A presumptive diagnosis of bone metastasis can be easily made when a patient with a history of colorectal cancer develops bone lesions that are seen on follow-up imaging. In this case report, we describe a patient whose multiple bone lesions were wrongly attributed to a recurrence of rectal cancer rather than being identified as multiple myeloma lesions. When clinicians detect new, abnormal, bony lesions in a patient with a previous history of cancer, they should consider diseases such as multiple myeloma in their differential diagnosis.

In Vitro Adenosine Triphosphate-Based Chemotherapy Response Assay as a Predictor of Clinical Response to Fluorouracil-Based Adjuvant Chemotherapy in Stage II Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We evaluated the usefulness of the in vitro adenosine triphosphate-based chemotherapy response assay (ATP-CRA) for prediction of clinical response to fluorouracil-based adjuvant chemotherapy in stage II colorectal cancer. MATERIALS AND METHODS: Tumor specimens of 86 patients with pathologically confirmed stage II colorectal adenocarcinoma were tested for chemosensitivity to fluorouracil. Chemosensitivity was determined by cell death rate (CDR) of drug-exposed cells, calculated by comparing the intracellular ATP level with that of untreated controls. RESULTS: Among the 86 enrolled patients who underwent radical surgery followed by fluorouracil-based adjuvant chemotherapy, recurrence was found in 11 patients (12.7%). The CDR ≥ 20% group was associated with better disease-free survival than the CDR < 20% group (89.4% vs. 70.1%, p=0.027). Multivariate analysis showed that CDR < 20% and T4 stage were poor prognostic factors for disease-free survival after fluorouracil-based adjuvant chemotherapy. CONCLUSION: In stage II colorectal cancer, the in vitro ATP-CRA may be useful in identifying patients likely to benefit from fluorouracil-based adjuvant chemotherapy.

Clinical Implications of Microsatellite Instability in T1 Colorectal Cancer

PURPOSE: The estimation of regional lymph node metastasis (LNM) risk in T1 colorectal cancer is based on histologic examination and imaging of the primary tumor. High-frequency microsatellite instability (MSI-H) is likely to decrease the possibility of metastasis to either regional lymph nodes or distant organs in colorectal cancers. This study evaluated the clinical implications of MSI in T1 colorectal cancer with emphasis on the usefulness of MSI as a predictive factor for regional LNM. MATERIALS AND METHODS: A total of 133 patients who underwent radical resection for T1 colorectal cancer were included. Genomic DNA was extracted from normal and tumor tissues and amplified by polymerase chain reaction (PCR). Five microsatellite markers, BAT-25, BAT-26, D2S123, D5S346, and D17S250, were used. MSI and clinicopathological parameters were evaluated as potential predictors of LNM using univariate and multivariate analyses. RESULTS: Among 133 T1 colorectal cancer patients, MSI-H, low-frequency microsatellite instability (MSI-L), and microsatellite stable (MSS) colorectal cancers accounted for 7.5%, 6%, and 86.5%, respectively. MSI-H tumors showed a female predominance, a proximal location and more retrieved lymph nodes. Twenty-two patients (16.5%) had regional LNM. Lymphovascular invasion and depth of invasion were significantly associated with LNM. There was no LNM in 10 MSI-H patients; however, MSI status was not significantly correlated with LNM. Disease-free survival did not differ between patients with MSI-H and those with MSI-L/MSS. CONCLUSION: MSI status could serve as a negative predictive factor in estimating LNM in T1 colorectal cancer, given that LNM was not detected in MSI-H patients. However, validation of our result in a different cohort is necessary.

Management of Opportunistic Infections after Organ Transplantation / 대한이식학회지

Solid organ transplantation is a therapeutic option for end-stage organ diseases. However, complications including infection and graft rejection, which are related to immunosuppressive therapy, remain the major causes of morbidity and mortality following solid organ transplantation. The optimal approach to infection in solid organ transplant recipients is prevention; failing this, prompt and aggressive diagnosis and therapy are essential. In addition, the epidemiology of infections after solid organ transplantation has shifted as a result of changes in immunosuppressive strategies and improved survival. Immunosuppression must be linked with appropriate vaccinations, donor and recipient screening, patient education regarding infectious risks and lifestyle, monitoring, and antimicrobial prophylaxis.

Underweight Body Mass Index as a Predictive Factor for Surgical Site Infections after Laparoscopic Appendectomy

PURPOSE: Analyses of risk factors associated with surgical site infections (SSIs) after laparoscopic appendectomy (LA) have been limited. Especially, the association of an underweight body mass index (BMI) with SSIs has not been clearly defined. This study aimed to identify the impact of underweight BMI in predicting SSIs after LA. MATERIALS AND METHODS: The records of a total of 101 consecutive patients aged > or =16 years who underwent LA by a single surgeon between March 2011 and December 2012 were retrieved from a prospectively collected database. The rate of SSIs was compared among the underweight, normal and overweight and obese groups. Also, univariate and multivariate analyses were performed to identify the factors associated with SSIs. RESULTS: The overall rate of SSIs was 12.8%. The superficial incisional SSI rate was highest in the underweight group (44.4% in the underweight group, 11.0% in the normal group, and 0% in the overweight and obese group, p=0.006). In univariate analysis, open conversion and being underweight were determined to be risk factors for SSIs. Underweight BMI was also found to be a significant predictor for SSIs in multivariate analysis (odds ratio, 10.0; 95% confidence interval, 2.0-49.5; p=0.005). CONCLUSION: This study demonstrated underweight BMI as being associated with SSIs after LA. Surgeons should be more cautious to prevent SSIs in patients that are underweight when performing LA.

Laparoscopic Appendectomy: Is There a Learning Curve after Completion of Colorectal Fellowships Training?

PURPOSE: Recent studies have shown that the procedure of laparoscopic appendectomy requires a learning curve before mastering. The aim of this study was to investigate the question of whether a surgeon who has been working as a first assistant for training in laparoscopic colorectal surgery can perform laparoscopic appendectomy without previous experience as an operator in laparoscopic appendectomy. METHODS: Ninety consecutive patients who underwent laparoscopic appendectomy by a single surgeon were retrospectively enrolled in this study. The operating surgeon completed fellowship training of the colorectal cancer division as a first assistant for two years. The patients were divided into two groups by consecutive order: Group (A) included the initial 45 patients and Group (B) included the next 45 patients. The clinical patient demographics, histological diagnosis, and outcome variables including operation time, conversion to open surgery, complications, and length of hospital stay were compared between the two groups. RESULTS: No difference in operation time was observed between the groups (mean: 58.22 min vs 66.6 min, p=0.097). Open conversion rate and drain insertion rate were similar between the two groups. There was no difference in length of hospital stay. Overall complication rate did not differ between the two groups. Moving average curve showed no specific time shortening point within these 90 enrolled patients. CONCLUSION: This study demonstrates that laparoscopic appendectomies performed by a surgeon who had achieved a training course as an assistant in laparoscopic colorectal surgery were performed safely without any difficulties during the learning period. This finding needs further validation in additional large-scale studies.

Feasibility and Safety of a Fold-Over Diverting Ileostomy Reversal After Rectal Cancer Surgery: Case-Matched Comparison to the Resection Technique

PURPOSE: Compared to the stapling technique, the fold-over technique (FO) has the benefit of avoiding the sacrifice of the bowel segment. The aim of this study was to compare short-term outcomes between the FO and a conventional resection. METHODS: Between June 2008 and March 2012, a total of 242 patients who underwent a diverting ileostomy reversal after rectal cancer surgery were selected. Among them, 29 patients underwent the FO. Using propensity scores to adjust for body mass index, previous abdominal surgery history, rectal cancer surgery type (open vs. minimally invasive), and reason for ileostomy (protective aim vs. leakage management), we created a well-balanced cohort by matching each patient who underwent the FO, as the study group, with two patients who underwent a stapled or a hand-sewn technique with bowel resection (RE), as the control group (FO : RE = 1 : 2). Morbidity and perioperative recovery were compared between the two groups. RESULTS: Twenty-four and forty-eight patients were allocated to the FO and the RE groups, respectively. The mean operation time was 91 +/- 26 minutes in the FO group and 97 +/- 34 minutes in the RE group (P = 0.494). The overall morbidity rates were not different between the two groups (12.5% in FO vs. 14.6% in RE, P = 1.000). The rate of postoperative ileus was similar between the two groups (8.3% in FO vs. 12.5% in RE, P = 0.710). Although time to resumption of soft diet was shorter in the FO group than in the RE group, the lengths of hospital stay were not different. CONCLUSION: The FO and the conventional resection have similar short-term clinical outcomes for diverting ileostomy reversal.

Clinical impact of fat clearing technique in nodal staging of rectal cancer after preoperative chemoradiotherapy / 대한외과학회지

PURPOSE: This study was designed to evaluate the efficacy of a fat clearing technique for accurate nodal staging of rectal cancer patients after preoperative chemoradiotherapy (CRT). METHODS: A total of 19 patients with rectal cancer within 10 cm from anal verge were divided into two groups: non-CRT group (n = 10) and CRT group (n = 9). For pathologic assessment, lymph node (LN) harvest was performed using conventional manual dissection followed by a fat clearing technique. RESULTS: A median of 3.0 additional LNs in non-CRT group and 3.8 LNs in CRT group were identified by the fat clearing technique. When subanalysis was performed in patients with fewer than 12 retrieved LNs, a median of 4.0 extra LNs in non-CRT group and 3.5 extra LNs in CRT group were identified after the fat clearing technique. None of additionally identified nodes were metastatic. In both groups, the median size of retrieved LNs following the fat clearing technique was smaller than that obtained by manual dissection (2.0 mm vs. 3.0 mm, P < 0.001). CONCLUSION: The fat clearing technique allowed detection of additional LNs that were missed by the manual method, but these detected LNs were not proven to be metastatic.

Clinical Significance of Age at the Time of Diagnosis among Young Breast Cancer Patients / 한국유방암학회지

PURPOSE: The aims of this study were to investigate outcomes corresponding to age at diagnosis as categorized into 5-year intervals and to explore whether endocrine-responsive tumors display clinical benefits from endocrine therapy after chemotherapy among young breast cancer patients. METHODS: A total of 1,171 patients who were under 40 years old at diagnosis between 1985 and 2007 were divided into 3 subgroups: < or =30 years (Group I, 13.3%), 31-35 years (Group II, 30.5%), and 36-40 years (Control group, 56.2%). Clinicopathological factors and outcomes were compared using a chi-square test, the Kaplan-Meier method, and Cox's hazards models. RESULTS: There were no significant differences in the characteristics and treatment patterns between the 3 groups, except for the grade, hormone receptors expression, and use of endocrine therap. Group I showed the worst survival and subsequently Group II presented worse outcomes than the Control group, mainly among hormone receptors-positive patients. Groups I and II showed increased risks of recurrence and death in multivariate analyses. Among 529 hormone receptors-positive patients who received chemotherapy, favorable outcomes for patients who were treated with endocrine agents were demonstrated, mainly in patients aged 35 years or less. However, interaction tests between the use of endocrine therapy and age at diagnosis were not significant. CONCLUSION: Age at diagnosis is an independent prognostic factor and the age of 35 years is a rational cut-off among young patients. Our subgroup analysis suggests that endocrine therapy may provide additional benefits even in young breast cancers. Therefore, further researches should be directed towards improving outcomes for this population.