Association between Timing and Duration of Adjuvant Chemotherapy and Colorectal Cancer Survival in Korea, 2011-2014: A Nationwide Study based on the Health Insurance Review and Assessment Service Database.

Background: Population-based analyses of the treatment outcomes of colorectal cancer (CRC) in Asian countries are limited. Therefore, we conducted a nationwide study to assess the relationship between the timing and duration of adjuvant chemotherapy (AC) and survival in patients with CRC in South Korea. Methods: Data on AC from the Health Insurance Review and Assessment Service Database (HIRA) were analyzed, and the survival of patients who underwent curative-intent surgical resection for CRC between 2011 and 2014 was investigated. Results: From the HIRA data, 45,992 patients with stage II-III CRC were identified. Chemotherapy regimens were administered as follows: 10,640 (23.3%) received 5-fluorouracil and leucovorin/capecitabine (FL/CAP), 13,083 (28.7%) received FL/CAP plus oxaliplatin (FOLFOX/CAPOX), 299 (0.7%) received uracil and tegafur/doxifluridine (UFT/D), and 21,570 (47.3%) underwent surgery alone. Patients who did not receive AC had worse survival than those who received AC in both the colon and rectum groups (HR, 1.96, 95% CI, 1.85-2.07 and HR, 2.18, 95% CI, 2.01-2.37, respectively). Regarding patients with stage II-III CRC, AC initiation ≥ 2 months after surgery was associated with a significant decrease in overall survival (OS) (FL/CAP: HR, 1.82; 95% CI, 1.53-2.17 and FOLFOX/CAPOX: HR, 2.92; 95% CI, 2.47-3.45); however, the effects of UFT/D regimens were not statistically significant. For patients with stage II-III colon cancer, AC <3 months had lower OS (FL/CAP: HR, 3.72, 95% CI, 2.80-4.94; FOLFOX/CAPOX: HR, 2.15, 95% CI, 1.87-2.47; and UFT/D: HR, 1.74, 95% CI, 0.56-5.41). In terms of patients with stage II-III rectal cancer, AC <3 months, regardless of chemotherapy regimens, had a significant lower survival (FL/CAP: HR, 1.91, 95% CI, 1.66-2.20; FOLFOX/CAPOX: HR, 2.20, 95% CI, 1.75-2.77; and UFT/D: HR, 3.71, 95% CI, 1.45-9.44). Conclusions: Postoperative time to initiation and duration of AC were associated with survival. Based on our results, initiating AC within 2 months after surgery and administering AC for >3 months can potentially have an OS benefit in patients with stage II-III CRC.

Clinical characteristics and survival of colorectal cancer patients in Korea stratified by age.

BACKGROUND/AIMS: This nationwide study was undertaken to determine differences in clinicopathologic characteristics and survival of patients with colorectal cancer (CRC) according to age using big data from the Korean National Health Insurance Service (NHIS). METHODS: The NHIS data including quality assessment of CRC by the Health Insurance Review & Assessment Service in Korea between 2011 and 2014 were analyzed. Based on age, patients were divided into three groups: not-old patients (< 65), young-old patients (65 to 74 years old) and old-old patients (≥ 75 years old). RESULTS: We included 71,513 CRC patients. The median follow-up duration was 3.2 years (range, 0.003 to 5.5). Male patients constituted 60%. The median age of patients was 65 years (range, 18 to 102). Colon was the cancer site in 59.8% of not-old patients, 62.9% of young-old patients, and 66.1% of old-old patients. Compared to not-old patients, young-old and old-old patients were more likely to be diagnosed with colon adenocarcinoma and well/moderate differentiation or adequate differentiation (all p < 0.001). Old patients underwent more emergency operation (p < 0.001) and received less adjuvant therapy in stage I-III (p < 0.001). The probability of 3-year survival of young-old or old-old patients was worse than that for not-old patients (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.46 to 1.64) (HR, 3.19; 95% CI, 3.03 to 3.37). CONCLUSION: Old patients with CRC show different histology from younger patients. They are more frequently to have colon as primary lesion. They undergo less adjuvant therapy. Further studies and evidence-based guidelines for older patients with CRC are warranted to improve their outcome.

Mapping Korean EDI Medical Procedure Code to SNOMED CT.

The Electronic Data Interchange (EDI) medical procedure code is the code used for health insurance claims in Korea. We mapped Korean EDI codes to SNOMED CT to explore the global interoperability of health insurance claims data. We developed rules for mapping based on the mapping guideline provided by SNOMED CT International. The first and second authors mapped 726 EDI codes used to claim reimbursement in five specialty areas to SNOMED CT. Eight subject matter experts reviewed the mapping results. Out of 726 procedure codes, 82.5% were exactly or partially mapped to SNOMED CT. An EDI code was mapped to an average of 2.04 SNOMED CT concepts. Twenty-one attributes were identified in the EDI codes mapped to SNOMED CT concepts. We identified strategies to improve the EDI code in this study. They include introducing hierarchical structures, adding inclusion and exclusion criteria for procedure codes, and improving EDI code labels.

Effect of Adjuvant Chemotherapy on Stage II Colon Cancer: Analysis of Korean National Data.

PURPOSE: Debates exist regarding the effectiveness of adjuvant chemotherapy for stage II colon cancer. This study aimed to investigate the current status of adjuvant chemotherapy and its impact on survival for Korean stage II colon cancer patients by analyzing the National Quality Assessment data. MATERIALS AND METHODS: A total of 7,880 patientswho underwent curative resection for stage II colon adenocarcinoma between January 2011 andDecember 2014 in Koreawere selected randomly as evaluation subjects for the quality assessment. The factors that influenced overall survival were identified. The high-risk group was defined as having at least one of the following: perforation/ obstruction, lymph node harvest less than 12, lymphovascular/perineural invasion, positive resection margin, poor differentiation, or pathologic T4 stage. RESULTS: The median follow-up period was 38 months (range, 1 to 63 months). Chemotherapy was a favorable prognostic factor for either the high- (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.38 to 0.59; p < 0.001) or low-risk group (HR, 0.74; 95% CI, 0.61 to 0.89; p=0.002) in multivariate analysis. This was also the case in patients over 70 years of age. The hazard ratio was significantly increased as the number of involved risk factors was increased in patients who didn't receive chemotherapy. Adding oxaliplatin showed no difference in survival (HR, 1.36; 95% CI, 0.91 to 2.03; p=0.132). CONCLUSION: Adjuvant chemotherapy can be recommended for stage II colon cancer patients, but the addition of oxaliplatin to the regimen must be selective.

Impact of prior abdominal surgery on postoperative prolonged ileus after ileostomy repair.

BACKGROUND AND AIMS: Postoperative ileus (POI) is one of the most common reasons for sustained hospital stays after ileostomy repair. Although many factors have been investigated as POI risk factors, the investigation of the impact of prior abdominal surgery (PAS) before rectal cancer surgery has been limited. This study aimed to identify the impact of PAS as a risk factor for POI after ileostomy repair. MATERIAL AND METHODS: A total of 220 consecutive patients with rectal cancer who underwent ileostomy repair were enrolled. The patients were divided into PAS-positive and PAS-negative groups according to the history of PAS before rectal cancer surgery. Univariate and multivariate analyses were performed to identify the clinicopathological factors associated with POI. RESULTS: The PAS-positive group had a longer operation time (111 min vs. 93.4 min, p=0.029) and a greater length of hospital stay (10 days vs. 7.8 days, p=0.003) compared with the PAS-negative group. POI was more frequent in the PAS-positive group (23.1% vs. 6.2%, p=0.011). The POI rate in the entire cohort was 8.1%. The repair method (stapled side-to-side vs. hand-sewn end-to-end, odds ratio OR=3.6, 95% confidence interval CI=1.2-11.1, p=0.022) and PAS (odds ratio=4.0, 95% confidence interval=1.2-12.8, p=0.017) were significant predictors of POI in the multivariate analysis. CONCLUSIONS: This study suggests that PAS before rectal cancer surgery is associated with POI after ileostomy repair.

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.

Outcomes of laparoscopic surgery in pathologic T4 colon cancers compared to those of open surgery.

INTRODUCTION: Despite the oncologic safety of laparoscopic surgery in colon cancer management, laparoscopy is not regarded as a standard treatment for T4 colon cancer. The aim of this study was to investigate the short-term and long-term oncologic outcomes of laparoscopic surgery in patients with locally advanced colon cancer. MATERIAL AND METHOD: From March 2003 to June 2013, a total of 109 consecutive patients with proven pathologic T4 colon cancer were enrolled. These patients were divided into the laparoscopy group (LG, n = 52) and the open group (OG, n = 57). Perioperative and long-term oncologic outcomes were compared between the two groups. RESULTS: In the LG, open conversion occurred in four patients (7.6%). Combined resection was less commonly performed in the LG (13.5%) than in the OG (36.8%, P = 0.005). Operation time was similar between the two groups. In the LG, blood loss (129 mL vs. 437 mL, P < 0.001) and overall complication rate (13.5 vs. 36.8%, P = 0.005) were lower and length of hospital stay was shorter (median 7 vs. 17 days, P < 0.001) than in the OG. The 5-year overall survival rate was 60.7% for the LG and 61.9% for the OG (P = 0.817). Local recurrence-free survival did not differ between the groups (88.9% in LG vs. 88.1% in OG, P = 0.725). CONCLUSION: Considering the benefits of early recovery and similar oncologic outcomes, laparoscopic surgery in T4 colon cancer could be a viable option in selected patients.

A Comparison of Open, Laparoscopic, and Robotic Surgery in the Treatment of Right-sided Colon Cancer.

INTRODUCTION: Multidimensional comparison between open, laparoscopy, and robotic surgery in the management of right-sided colon cancer are lacking. The aim of this study was to compare the early perioperative results and oncologic outcomes among the 3 different methods. PATIENTS AND METHODS: Between June 2007 and 2011, a total of 96 patients who underwent right hemicolectomy in a single institution were classified into the open surgery (OS; n=33), the laparoscopy surgery (LS; n=43), and the robot surgery (RS; n=20) groups. Perioperative and oncologic outcomes were compared among the 3 groups. RESULTS: Patient demographics were comparable. Operation time was significantly longer in the RS and LS than the OS (P<0.001). There was 1 OS conversion in LS. There was no difference of total retrieved lymph node numbers among the 3 groups. Postoperative recovery was faster and hospital stay was shorter in RS than OS. However, there was no difference between LS and RS. After the median 40 months' follow-up, 5-year disease-free survival was similar among the OS, LS, and RS (87.7%, 84%, and 89.5%, respectively). Total charge and total patient charge were significantly higher in RS than the others. CONCLUSIONS: Our comparative study demonstrates that the RS have better short-term outcomes in reducing hospital stay compared with the OS, but similar to the LS. Although the oncologic outcomes are similar, the benefit of RS in right hemicolectomy is unclear considering a high cost of RS.

The efficacy of cap-assisted colonoscopy performed by a single endoscopist in patients after colorectal resection.

BACKGROUND: The use of a transparent cap is regarded as a simple method to obtain better outcomes compared with standard colonoscopy. In this study, we investigated whether cap-assisted colonoscopy can improve the quality of procedure-related outcomes in patients with a history of colorectal resection. METHODS: This study was designed as a prospective, randomized, controlled trial conducted at a single tertiary center by a single endoscopist (Kang J.). A total 183 patients after colorectal resection due to primary colorectal cancer were enrolled and 1:1 randomized to undergo either cap-assisted colonoscopy (CAP group) or standard colonoscopy (non-CAP group). The primary endpoint was the comparison of cecal intubation time between the 2 groups. RESULTS: The mean cecal intubation time of the CAP group (n = 89) was significantly shorter than that of the non-CAP group (n = 89) (538 seconds vs 677 seconds, P = 0.024). In the CAP group, the endoscopist performed faster intubation than average more often compared with the non-CAP group (71.9% vs 57.3%). In regard to moving average curve, the CAP group showed a gentle slope during the learning period, while the non-CAP group showed a steep decrease. CONCLUSION: The cap-assisted colonoscopy could reduce cecal intubation time and achieve more frequent faster intubation compared with standard colonoscopy in patients after colorectal resection.

Xanthogranulomatous Appendicitis Mimicking Residual Burkitt's Lymphoma After Chemotherapy.

The case of a 23-year-old female treated with aggressive high-dose therapy for Burkitt's lymphoma is reported. A positron emission tomography and computed tomography scan after completion of chemotherapy revealed a residual hypermetabolic lesion in the right pelvic cavity. A pelvic magnetic resonance imaging scan showed circumferential wall thickening at the tip of the appendix. A laparoscopic exploration and appendectomy were performed, and a pathologic examination of the resected appendix revealed xanthogranulomatous appendicitis. This is a rare case of a xanthogranulomatous appendicitis mimicking remnant Burkitt's lymphoma after completion of chemotherapy.

Relationship Between 18F-Fluorodeoxyglucose Uptake and V-Ki-Ras2 Kirsten Rat Sarcoma Viral Oncogene Homolog Mutation in Colorectal Cancer Patients: Variability Depending on C-Reactive Protein Level.

To evaluate clinical values of clinicopathologic and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT)-related parameters for prediction of v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation in colorectal cancer (CRC) and to investigate their variability depending on C-reactive protein (CRP) levels. In total, 179 CRC patients who underwent PET/CT scans before curative resection and KRAS mutation evaluation following surgery were enrolled. Maximum standardized uptake value (SUV max), peak standardized uptake value (SUV peak), metabolic tumor volume, and total lesion glycolysis were determined semiquantitatively. Associations between clinicopathologic and PET/CT-related parameters and KRAS expression were analyzed. Elevated CRP (> 6.0 mg/L; n = 47) was associated with higher primary tumor size, higher SUV max, SUV peak, metabolic tumor volume, and total lesion glycolysis, compared with those for the group with a CRP lower than that the cutoff value (< 6.0 mg/L; n = 132). Interestingly, the CRC patients (having CRP < 6.0 mg/L) with KRAS mutations had significantly higher (P < 0.05) SUV max and SUV peak values than the patients expressing wild-type KRAS mutations. Multivariate analysis revealed SUV max and SUV peak to be significantly associated with KRAS mutations (odds ratio = 3.3, P = 0.005, and odds ratio = 3.9, P = 0.004), together with histologic grade and lymph node metastasis. 18F-FDG uptake was significantly higher in CRC patients with KRAS mutations and with normal CRP levels. A severe local inflammation with raised CRP levels, however, might affect accurate 18F-FDG quantification in CRC tumors. Positron emission tomography/computed tomography-related parameters could supplement genomic analysis to determine KRAS expression in CRC; however, care should be exercised to guarantee proper patient selection.

In Vitro Adenosine Triphosphate-Based Chemotherapy Response Assay as a Predictor of Clinical Response to Fluorouracil-Based Adjuvant Chemotherapy in Stage II Colorectal Cancer.

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.

Short-term outcomes of the modified extralevator abdominoperineal resection for low rectal cancer (with videos).

BACKGROUND: Extralevator abdominoperineal resection had oncologic superiority with reduced local recurrence and improving survival rates. However, extended perineal resection resulted in complicated perineal reconstructions. Therefore, a new surgical technique to overcome previous limitations is required. This study aims to demonstrate a surgical procedure and outcomes of the modified extralevator abdominoperineal resection, which satisfies both an extended cylindrical resection and a convenient perineal wound closure by modification of the surgical dissection plane. METHODS: From September 2011 to February 2014, 12 consecutive patients (five males and seven females) who underwent the modified extralevator abdominoperineal resection for low rectal cancer were evaluated. Intraoperative and postoperative outcomes were assessed. Pathologic outcomes were evaluated for the oncologic results. RESULTS: The mean age was 55.3 ± 15.1 years, and body mass index was 21.8 ± 3.1 kg/m(2). Ten patients (83.3%) received preoperative chemoradiotherapy. The operations were performed by five cases of laparoscopic surgery, six cases of open surgery and one case of robotic surgery. The mean operation time was 258.8 ± 58.0 min. There were no conversions and no tumor perforations. Days to first soft diet was 4.7 ± 3.4 days, and the mean hospital stay was 11.2 ± 4.7 days. Postoperative complications were two cases of grade I, two cases of grade II and one case of grade III. There was one patient (8.3%) with a positive circumferential resection margin, and there was one case of local recurrence. CONCLUSIONS: The modified extralevator abdominoperineal resection was feasible and safe for patients with low rectal cancer with extended perineal dissection and convenient direct wound closure.

Robotic transverse colectomy for mid-transverse colon cancer: surgical techniques and oncologic outcomes.

Robot-assisted surgery for colon cancer has been reported in many studies, most of which worked on right and/or sigmoid colectomy. The aim of this study was to report our experience of robotic transverse colectomy with an intracorporeal anastomosis, provide details of the surgical technique, and present the theoretical benefits of the procedure. This is a retrospective review of prospectively collected data of robotic surgery for colorectal cancer performed by a single surgeon between May 2007 and February 2011. Out of 162 consecutive cases, we identified three robotic transverse colectomies, using a hand-sewn intracorporeal anastomosis. Two males and one female underwent transverse colectomies for malignant or premalignant disease. The mean docking time, time spent using the robot, and total operative time were 5, 268, and 307 min, respectively. There were no conversions to open or conventional laparoscopic technique. The mean length of specimen and number of lymph nodes retrieved were 14.1 cm and 6.7, respectively. One patient suffered from a wound seroma and recovered with conservative management. The mean hospital stay was 8.7 days. After a median follow-up of 72 months, there were no local or systemic recurrences. Robotic transverse colectomy seems to be a safe and feasible technique. It may minimize the necessity of mobilizing both colonic flexures, with facilitated intracorporeal hand-sewn anastomosis. However, further prospective studies with a larger number of patients are required to draw firm conclusions.

Effect of preoperative colonoscopic tattooing on lymph node harvest in T1 colorectal cancer.

OBJECTIVE: This study aimed to identify the impact of preoperative colonoscopic tattooing (PCT) on lymph node harvest in T1 colorectal cancer patients. MATERIAL AND METHODS: One hundred and forty-three patients were included who underwent curative resection and were diagnosed with T1 colorectal cancer. These patients were categorized into the tattooing group and the non-tattooing group depending on whether preoperative India ink tattooing was done. Clinicopathological findings and lymph node harvest were compared between the two groups. RESULTS: The median number of lymph nodes examined was 18 in the tattooing group and 13 in the non-tattooing group (p < 0.001). The rate of adequate lymph node harvest (retrieval of more than 12 lymph nodes) was higher in the tattooing group than that in the non-tattooing group (83.7 vs. 58.5 %, p = 0.002). The PCT was significantly associated with adequate lymph node harvest in multivariate analysis (hazard ratio, 3.8; 95 % confidence interval, 1.5-9.2; p = 0.003). Among the 40 patients who showed at least one carbon particle-containing lymph nodes, the positive lymph node rate was not different between carbon-containing LNs (0.9 %) and non-carbon-containing LNs (1.7 %). CONCLUSIONS: PCT was associated with higher lymph node yield in T1 colorectal cancer. It is questionable if tattooing has additional detection power as a sentinel lymph node mapping tool in T1 colorectal cancer.

Associations of colorectal cancer incidence with nutrient and food group intakes in korean adults: a case-control study.

This study aimed to examine the associations between intakes of various nutrients and food groups and colorectal cancer risk in a case-control study among Koreans aged 20 to 80 years. A total of 150 new cases and 116 controls were recruited with subjects' informed consent. Dietary data were collected using the food frequency questionnaire developed and validated by the Korea Centers for Disease Control and Prevention. Multivariate logistic regression models were used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for colorectal cancer incidence. High intakes of total lipid (ORT3 vs T1 = 4.15, 95% CI: 1.33-12.96, p for trend = 0.034), saturated fatty acid (ORT3 vs T1 = 2.96, 95% CI: 1.24-7.04, p for trend = 0.016) and monounsaturated fatty acid (ORT3 vs T1 = 3.04, 95% CI: 1.23-7.54, p for trend = 0.018) were significantly associated with increased incidence of colorectal cancer. High dietary fiber (ORT3 vs T1 = 0.22, 95% CI: 0.08-0.56, p for trend = 0.002) and vitamin C (ORT3 vs T1 = 0.38, 95% CI: 0.14-1.05, p for trend = 0.021) intakes were significantly associated with reduced colorectal cancer incidence. From the food group analysis, bread (ORT3 vs T1 = 2.26, 95% CI: 0.96-5.33, p for trend = 0.031), red meat (ORT3 vs T1 = 7.33, 95% CI: 2.98-18.06, p for trend < 0.001), milk·dairy product (ORT3 vs T1 = 2.42, 95% CI: 1.10-5.31, p for trend = 0.071) and beverage (ORT3 vs T1 = 3.17, 95% CI: 1.35-7.48, p for trend = 0.002) intakes were positively associated with colorectal cancer risk. On the other hand, high intake of traditional rice cake (ORT3 vs T1 = 0.35, 95% CI: 0.14-0.86, p for trend = 0.024) was linked with lower colorectal cancer incidence. In conclusion, eating a diet high in total lipid, saturated fatty acids and monounsaturated fatty acids is associated with higher incidence of colorectal cancer, whereas a diet high in dietary fiber and vitamin C was found to lower the incidence in Korean adults. Interestingly high traditional rice cake consumption is associated inversely with colorectal cancer incidence, warranting a future study.

The impact of lymph node size to predict nodal metastasis in patients with rectal cancer after preoperative chemoradiotherapy.

PURPOSE: During restaging after preoperative chemoradiotherapy (CRT), the assessment of lymph node (LN) metastasis is vital for selecting further treatment strategies. This study aimed to evaluate the impact of LN size to predict LN metastasis in rectal cancer patients after preoperative CRT. METHODS: A total of 30 consecutive patients who underwent preoperative CRT followed by curative resection of primary rectal cancer were selected as a study group (CRT group). As a control group (non-CRT group), 30 patients who underwent primary tumor resection were selected using a 1:1 case-match design. Matching criteria were gender, age, and clinical T stage. The size of each LN was measured from the surgical specimen. To clarify optimal cutoff values for node size according to the risk of detecting metastasis, receiving-operator characteristic (ROC) curves were generated. RESULTS: In the non-CRT group, 39/474 LNs were confirmed to have metastasis. In the CRT group, 29/422 LNs showed metastasis. The median size of metastatic LNs was 6.0 mm in CRT group, which was significantly larger than 4.0 mm in the non-CRT group (p = 0.006). The optimal cutoff value for determining metastasis in the CRT group was 4.5 mm, compared to 3.5 mm in the non-CRT group. The accuracy of the cutoff value was much higher in the CRT group (CRT vs. non-CRT, 77.9 vs. 59.9%). CONCLUSIONS: LN size is a strong indicator for prediction of regional LN metastasis in rectal cancer patients after preoperative CRT, compared to those without CRT.

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.

A case of tracheal metastasis in colon cancer: detection with 18F-FDG PET/CT.

A 44-year-old female patient received proctocolectomy and chemotherapy for a diagnosis of colon cancer 10 years previously and presented here with new onset of cough for 2 months and a progressive increase of her serum CA19-9 level. F-FDG PET/CT imaging revealed a hypermetabolic lesion within the trachea. Immunostaining confirmed that this lesion was a metastatic adenocarcinoma that originated from the patient's initial colon cancer. F-FDG PET/CT enabled localization of unusual endotracheal metastasis and facilitated the development of an appropriate treatment plan.

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 ≥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.