A survey investigating the current situation of the international visiting scholar program at the department of surgery in Korea

Purpose@#The number of international visiting scholars has been on the increase in Korea and we aim to investigate the program’s current situation. @*Methods@#This cross-sectional study is based on an online survey questionnaire responded by international visiting scholars in surgical departments of 8 Korean hospitals between 2014 and 2018 about their experiences and satisfaction with the visiting scholar program. @*Results@#A total of 1,496 international scholars from 80 countries visited various surgical departments in 8 Korean hospitals between 2014 and 2018. The numbers have been on the increase over the years. Out of 355 visiting scholars in 2018, 71 replied to the online survey, of whom 52 were male and 19 female, and mostly in their 30s and 40s. Information about the program was accessed mostly through friends or colleagues (42.3%) and international conferences (36.6%). The commonest funding source was private (35.2%) and more than half stayed for less than 3 months. The visiting scholar’s main roles were mostly observation or participation in surgery and clinical research. All but 1 were satisfied with the program (98.6%) and would recommend it to friends and colleagues, although the language barrier was identified as an inconvenience. Those aged 20–39 years with governmental or institutional funding were associated with stays of more than 1 year. @*Conclusion@#The number of international visiting scholars at surgical departments in Korean hospitals has been on the increase with high satisfaction levels. Improvements need to be made on funding sources and lengthening visiting period to maximize the benefits of the program.

Single-center Experience of 24 Cases of Tailgut Cyst

PURPOSE: Tailgut cysts are rare congenital or developmental lesions that arise from vestiges of the embryological hindgut. They are usually present in the presacral space. We report our single-center experience with managing tailgut cysts. METHODS: We conducted a retrospective analysis of 24 patients with tailgut cyst treated surgically at the Colorectal Surgery Department of Severance Hospital, Yonsei University, Seoul, South Korea, between 2007–2018. RESULTS: This study included 24 patients (18 females) with a median age of 51.5 years (range, 21–68 years). Ten cases were symptomatic and 14 were asymptomatic. Cysts were retrorectal in 21 patients. Cysts were below the coccyx level in 16 patients, opposite the coccyx in 6, and above the coccyx in 2. Cysts were supralevator in 5 patients, had a supra- and infralevator extension in 18 patients, and were infralevator in 1. Ten patients were managed using an anterior laparoscopic approach, 11 using a posterior approach, and 3 using a combined approach. Mean cyst size was 5.5 ± 2.7 cm. Postoperative complications were Clavien-Dindo (CD) classification grade II in 9 patients (37.5%) and CD grade III in 1 (4.2%). The posterior approach group showed the highest rate of complications (P = 0.021). Patients managed using a combined approach showed a larger cyst size (P < 0.001), longer operation times (P < 0.001), and a greater likelihood of tumor level above the coccyx (P = 0.002) compared to other approaches. The tumors of 2 male patients were malignant: 1 was a neuroendocrine tumor treated with radiotherapy, while the other was a closely followed adenocarcinoma. Median follow-up was 12 months (range, 1–66 months) with no recurrence. CONCLUSION: Tailgut cysts are uncommon but can cause perineal or pelvic pain. Complete surgical excision via an appropriate approach according to tumor size, location, and correlation with adjacent pelvic floor muscles is the key treatment.

Short-term Outcomes After Upfront Chemotherapy Followed by Curative Surgery in Metastatic Colon Cancer: A Comparison With Upfront Surgery Patients

PURPOSE: Upfront systemic chemotherapy with target agents has been recommended for patients with stage IV colon cancer. Some with partial response are considered for curative resection. There is high risk of developing postoperative complications following upfront systemic chemotherapy. We aimed to evaluate short-term perioperative outcomes of curative surgery after upfront chemotherapy in comparison with upfront surgery in patients with metastatic colon cancer.METHODS: Between January 2010 and October 2015, 146 patients (80 in the surgery first group, 66 in the upfront chemotherapy group) who underwent surgical resection before or after systemic chemotherapy for metastatic colon cancer were included in the present study. All decisions for treatment were made through a multidisciplinary team. Postoperative clinical outcomes and complications were analyzed to compare the groups.RESULTS: There was no difference between the 2 groups in terms of postoperative clinical outcomes. Overall complication rates were not different between the groups (surgery first group: 46.3% vs. upfront chemotherapy group: 60.6%; P = 0.084). When classified according to the Clavien-Dindo method, there was no difference between the 2 groups in terms of major complications (grade 3 or more) (surgery first group: 18.9% vs. upfront chemotherapy group: 27.5%; P = 0.374).CONCLUSION: There was no significant increase in major postoperative complications in metastatic colon cancer patients who received upfront chemotherapy followed by curative surgery. Careful patient selection and treatment planning are important.

Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

PURPOSE: Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients. METHODS: We identified stage I–III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis. RESULTS: Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07–2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22–2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05–3.29; P = 0.031) in stage III patients. CONCLUSION: RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

Carcinoembryonic antigen levels of tumor-draining venous blood as a prognostic marker in colon cancer

PURPOSE: Carcinoembryonic antigen (CEA) is a tumor marker for colorectal cancer (CRC) related to recurrence and prognosis. We examined the ability of the CEA level measured directly from a tumor drainage vein (dCEA) to predict the prognosis of CRC more accurately than those from a peripheral vein (pCEA).METHODS: Fifty-two patients who received curative resection for colon adenocarcinoma were enrolled. The patients were categorized into two groups according to normal pCEA ( < 5.9425 ng/mL, n=24) or elevated pCEA levels (≥5.9425 ng/mL, n=28). Blood was sampled at the time of surgery simultaneously from the tumor drainage vein and from the peripheral vein.RESULTS: The clinicopathologic variables showed no significant difference between the two groups. Patients with dCEA levels < 20.192 ng/mL showed better disease-free (P=0.009) and overall survival (P=0.033) curves than those with dCEA levels ≥20.192 ng/mL. Elevated dCEA levels were a significant prognostic factor for overall survival and disease-free survival in Cox proportional hazard model analysis (hazard ratio [HR]=399; 95% confidence interval [CI], 16.4–9,747; P < 0.001; HR=9.39, 95% CI, 1.29–68.006; P=0.026). In subgroup analysis, we compared the data of normal range of dCEA group and elevated dCEA group with normal pCEA; the overall survival rate of patients with normal dCEA was better and the disease-free survival rate was significantly better (P=0.003).CONCLUSION: CEA levels from a tumor drainage vein can be used as more accurate prognostic markers than levels from a peripheral vein in patients with colon cancer.

Novel anal sphincter saving procedure with partial excision of levator-ani muscle in rectal cancer invading ipsilateral pelvic floor

PURPOSE: Tumors at the level of the anorectal junction had required total levator-ani muscle excision to achieve an adequate resection margin. However, in the cases of tumor invading ipsilateral levator-ani muscle and intact external sphincter, en bloc resection of rectum with levator-ani muscle including tumor would be possible. This hemilevator excision (HLE) technique enables preserving the anal sphincter function while obtaining oncologic clearance and avoiding permanent colostomy in those patients. This study aimed to evaluate the surgical outcomes and feasibility of HLE. METHODS: Data on 13 consecutive patients who underwent HLE for pathologically proven low rectal cancer were retrospectively collected. All 13 patients presented low rectal cancer at the anorectal ring level that was suspected to invade or abut to the ipsilateral side of the levator-ani muscle. RESULTS: A secure resection margin was achieved in all cases, and anastomotic leakage occurred in 2 patients. During follow-up, 3 patients experienced tumor recurrence (2 systemic and 1 local). Among 6 patients who underwent diverting ileostomy closure after the index operation, 2 complained of fecal incontinence. The other 4 patients without fecal incontinence showed <10 times of bowel movement per day. Accessing their incontinence scale, mean Wexner score was 9.4. CONCLUSION: HLE is a novel sphincter-preserving technique that can be a treatment option for low rectal cancer invading ipsilateral levator-ani muscle, which has been an indication for abdominoperineal resection (APR) or extralevator APR. However, the long-term oncologic and functional outcomes of this procedure still need to be assessed to confirm its validity.

Efficacy of Immunohistochemical Staining in Differentiating a Squamous Cell Carcinoma in Poorly Differentiated Rectal Cancer: Two Case Reports

A rectal carcinoma, including primary an adenosquamous and a squamous cell carcinoma (SCC), is a very rare disease, accounting for 0.025% to 0.20% of all large-bowel malignant tumors. Because SCCs have a higher mortality than adenosquamous carcinomas, determining whether the primary rectal cancer exhibits an adenomatous component or a squamous component is important. While differentiating between these 2 components, especially in poorly differentiated rectal cancer, is difficult, specific immunohistochemical stains enable accurate diagnoses. Here, we report the use of immunohistochemical stains to distinguish between the adenomatous and the squamous components in 2 patients with low rectal cancer, a 58-year-old man and a 73-year-old woman, who were initially diagnosed using the histopathologic results for a poorly differentiated carcinoma. These data suggest that using these immunohistochemical stains will help to accurately diagnose the type of rectal cancer, especially for poorly differentiated carcinomas, and will provide important information to determine the proper treatment for the patient.

Prognostic Impact of Immunonutritional Status Changes During Preoperative Chemoradiation in Patients With Rectal Cancer

PURPOSE: Previous studies have demonstrated the prognostic impact of the prognostic nutritional index (PNI), a proposed indicator of immunonutritional statuses of surgical patients, on patients with various gastrointestinal cancers. Although the prognostic impact of the PNI on patients with colorectal cancer has been well established, its value has not been studied in patients treated with preoperative chemoradiation (pCRT). This study aimed to evaluate the prognostic impact of PNI on patients receiving pCRT for locally advanced rectal cancer (LARC). METHODS: Patients with LARC who underwent curative pCRT followed by surgical resection were enrolled. The PNI was measured in all patients before and after pCRT, and the difference in values was calculated as the PNI difference (dPNI). Patients were classified according to dPNI (10). Clinicopathologic parameters and long-term oncologic outcomes were assessed according to dPNI classification. RESULTS: No significant intergroup differences were observed in clinicopathologic parameters such as age, histologic grade, tumor location, tumor-node-metastasis stage, and postoperative complications. Approximately 53% of the patients had a mild dPNI (10). Univariate and multivariate analyses identified the dPNI as an independent prognostic factor for disease-free status (P < 0.01; hazard ratio [HR], 2.792; 95% confidence interval [CI], 1.577–4.942) and for cancer-specific survival (P = 0.012; HR, 2.469; 95%CI, 1.225–4.978). CONCLUSION: The dPNI is predictive of long-term outcomes in pCRT-treated patients with LARC. Further prospective studies should investigate whether immune-nutritional status correction during pCRT would improve oncologic outcomes.

Relation of the Expression of Cyclooxygenase-2 in Colorectal Adenomas and Adenocarcinomas to Angiogenesis and Prognosis

PURPOSE: Recent studies have shown that cyclooxygenase (COX)-2 may be involved in tumor growth, invasion and apoptosis in various carcinomas. Vascular endothelial growth factor (VEGF) has a potent angiogenic activity, and COX-2 promotes angiogenesis by modulating angiogenic factors, including VEGF. Endothelial growth factor receptor (EGFR) is considered as a factor of cell growth, maturation and cell death. The current study was designed to investigate the possible roles of COX-2 in colorectal tumor progression and angiogenesis. METHODS: Fifty colorectal adenomas and forty adenocarcinomas were investigated by using immunohistochemical staining for COX-2, VEGF and EGFR. The correlations of COX-2, VEGF and EGFR with the grade of dysplasia, the size of the adenoma, and various clinicopathologic factors were studied. RESULTS: The expressions of COX-2, VEGF and EGFR were each significantly correlated with carcinomatous transformation, and the expressions of COX-2 and VEGF were significantly correlated. COX-2 and EGFR showed correlations with adenomas rather than adenocarcinomas. However, no correlations of COX-2, VEGF and EGFR expression to other clinicopathologic factors, except tumor size in EGFR expression, were detected. CONCLUSION: These results suggest that COX-2 may play an important role in carcinogenesis through interaction with VEGF and EGFR in human colorectal cancer.

Thyroid Abscess in an Adult: A Case Report and Review of the Literature / 대한내분비외과학회지

It is well known that the thyroid gland is resistant to infection due to its anatomic and physiological characteristics. Thyroid abscess in an adult is extremely rare. It is more commonly found in children than in adults. The treatment goal of this disease is to eliminate the source of infection by incision and drainage, or by a thyroidectomy and administration of antibiotics, depending on the clinical findings.We report a case of thyroid abscess found in a 29-year-old woman. The patient presented with a painful mass in the left thyroid for 6 days duration. The patient had a history of subacute thyroiditis that was treated with steroidsand thyroid hormone. Computed tomography showed a large, fluid contained, cystic predominant mass in the left thyroid. Aspiration of the cystic fluid confirmed the presence of the thyroid abscess. Under local anesthesia, an incision and drainage was performed. The patient improved dramatically after surgery and the patient was discharged 8 days later.