Breast Cancer Statistics in Korea, 2018 / 한국유방암학회지

Breast cancer is the most common malignancy in Korean women, and its incidence continues to increase. The Korean Breast Cancer Society (KBCS) established a nationwide breast cancer database through its online enrollment program in 1996. This study aimed to analyze the clinical characteristics of breast cancer in Korea, and to assess the pattern of changes in breast cancer management in 2018. We analyzed the KBCS and Korea Central Cancer Registry (KCCR) databases in 2018. In 2018, 28,157 patients were newly diagnosed with breast cancer, of whom 4,510 had noninvasive breast cancer and 23,647 had invasive breast cancer. The age-standardized rate of breast cancer in 2018 was 79.0 per 100,000 women (65.6 invasive, 13.4 noninvasive). The median age of female patients diagnosed with breast cancer in 2018 was 52 years, and the incidence of breast cancer was the highest in the 40–49-years age group (9,432 patients, 33.6%). The proportion of patients with stage 0 and stage I breast cancer continued to increase, accounting for 63.8% of cases, and breast-conserving surgery was performed more often than mastectomy (66.2% vs. 33.0%). The most common subtypes of breast cancer were hormone receptor [HR]-positive and human epidermal growth factor receptor-2 (HER2)-negative types (65.9% of cases), while the HR-negative and HER2-positive types accounted for 9.2% of cases. According to the KCCR data, from 2014 to 2018, the 5-year relative survival rate of patients with breast cancer was 93.3%, which was 14.0% higher than that from 1993 to 1995 (79.3%). The clinical characteristics of breast cancer in Korea have been changing, and national databases can improve our understanding of the disease characteristics of Korean women. Therefore, updating the KBCS registry is important for the effective management of breast cancer in Korea.

Breast Cancer Statistics in Korea, 2018 / 한국유방암학회지

Breast cancer is the most common malignancy in Korean women, and its incidence continues to increase. The Korean Breast Cancer Society (KBCS) established a nationwide breast cancer database through its online enrollment program in 1996. This study aimed to analyze the clinical characteristics of breast cancer in Korea, and to assess the pattern of changes in breast cancer management in 2018. We analyzed the KBCS and Korea Central Cancer Registry (KCCR) databases in 2018. In 2018, 28,157 patients were newly diagnosed with breast cancer, of whom 4,510 had noninvasive breast cancer and 23,647 had invasive breast cancer. The age-standardized rate of breast cancer in 2018 was 79.0 per 100,000 women (65.6 invasive, 13.4 noninvasive). The median age of female patients diagnosed with breast cancer in 2018 was 52 years, and the incidence of breast cancer was the highest in the 40–49-years age group (9,432 patients, 33.6%). The proportion of patients with stage 0 and stage I breast cancer continued to increase, accounting for 63.8% of cases, and breast-conserving surgery was performed more often than mastectomy (66.2% vs. 33.0%). The most common subtypes of breast cancer were hormone receptor [HR]-positive and human epidermal growth factor receptor-2 (HER2)-negative types (65.9% of cases), while the HR-negative and HER2-positive types accounted for 9.2% of cases. According to the KCCR data, from 2014 to 2018, the 5-year relative survival rate of patients with breast cancer was 93.3%, which was 14.0% higher than that from 1993 to 1995 (79.3%). The clinical characteristics of breast cancer in Korea have been changing, and national databases can improve our understanding of the disease characteristics of Korean women. Therefore, updating the KBCS registry is important for the effective management of breast cancer in Korea.

Comparative Accuracy of Preoperative Tumor Size Assessment on Ultrasonography and Magnetic Resonance Imaging in Ductal Carcinoma In Situ

Purpose@#The purpose of this study was to compare the accuracy of preoperative breast tumor size measured by ultrasonography (US) and magnetic resonance imaging (MRI) in patients with ductal carcinoma in situ (DCIS). @*Methods@#Medical records of 74 patients postoperatively diagnosed with DCIS were retrospectively analyzed. Tumor size measurements obtained using the two imaging modalities were compared for accuracy with those obtained during the final pathologic examination. Patients with only microcalcification on imaging were excluded. @*Results@#For all patients, Lin’s concordance correlation coefficient (CCC) of MRI was 0.725, which was more accurate than 0.670 of US. In subgroup analysis, CCC of US was 0.757, more accurate than 0.697 of MRI in premenopausal DCIS patients. Background parenchymal enhancement (BPE) was the only risk factor deteriorating the accuracy of US and MRI examinations. Moderate and marked BPE was associated with the inaccurate tumor size estimations in both US and MRI (odds ratio [OR]:2.23, 95% confidence interval [CI]=1.12−3.52, p=0.001 in US, OR:8.16, 95% CI=1.17−15.2, p=0.031 in MRI). @*Conclusion@#MRI was more accurate for measuring tumor size in patients with DCIS. Moderate and marked BPE was a risk factor that prevented accurate measurement of preoperative tumor size. In premenopausal patients, US would help measure tumor size accurately.

Breast Cancer Statistics in Korea in 2017: Data from a Breast Cancer Registry / 한국유방암학회지

This article describes the breast cancer statistics in Korea, including the incidence, type of surgical procedure, stage, and molecular subtype, using the Korean Breast Cancer Society (KBCS) and Korea Central Cancer Registry data. There were a total of 26,534 new breast cancer diagnoses in 2017 in Korea, of which 4,139 were carcinoma in situ cases and 22,395 were invasive cancer cases. The age standardized rate of breast cancer was 75.3 per 100,000 women in 2017 (63.0 of invasive carcinoma and 12.3 of carcinoma in situ), and it has been steadily increasing across all age groups. Breast cancer occurred most commonly in the 40–49 age group. Compared to 2016, breast conserving surgery (BCS) has increased, and 67.4% of patients were treated with BCS in 2017. The proportions of stage 0 and stage I have continued to increase, accounting for 60.7%. The most common subtype of breast cancer was hormone receptor (HR) positive and human epidermal growth factor receptor-2 (HER2) negative type comprising 65.9% of the cases, whereas HR negative and HER2 positive type was the rarest comprising 10.2% of the cases. The 5-year relative survival rate of breast cancer patients had increased by 14.0% from 79.2% in 1993–1995 to 93.2% in 2013–2017. It is essential to actively enter breast cancer data into the KBCS registry to improve our understanding.

Risk factor for contralateral occult carcinoma in patients with unilateral papillary thyroid carcinoma

Purpose@#The extent of surgery necessary in patients with unilateral papillary thyroid carcinoma (PTC) on preoperative radiologic imaging is still in doubt. In this study, we aimed to define risk factors that could be indicators for malignant nodules in the contralateral thyroid lobe. @*Methods@#We included 438 patients who underwent total thyroidectomy between January 2011 and December 2014 at our institution. In this study, patients were divided into two groups according to the presence of contralateral occult carcinoma identified by postoperative pathological examination. We analyzed the clinicopathologic factors including characteristics of coexistent nodules in the contralateral lobe based on preoperative radiological imaging. @*Results@#A total of 96 patients (21.9%) had PTC in the contralateral lobe. There were no significant differences between patients with or without contralateral occult carcinoma with respect to gender, age, primary tumor size, central lymph node metastasis, extrathyroidal extension and stage. The presence of Hashimoto’s thyroiditis was an independent predictive factor for contralateral occult carcinoma (P=0.01). @*Conclusion@#A risk factor for contralateral occult carcinoma in unilateral PTC patients is Hashimoto’s thyroiditis. Therefore, more caution is needed when determining optimal surgical methods for PTC patients with Hashimoto’s thyroiditis.

Accuracy of Radiological Axillary Staging for Breast Cancer Patients with Neoadjuvant Chemotherapy

Purpose@#Neoadjuvant chemotherapy (NACT) in breast cancer patients has the advantage of decreasing related morbidities by reducing the extent of axillary surgery. However, it remains a controversy with regards to the appropriate extent of axillary lymph node dissection after NACT. Therefore, this study aims to investigate the accuracy of breast ultrasonography (US) and breast magnetic resonance imaging (MRI) to assess the axillary nodal status after NACT. @*Methods@#We reviewed pre- and post-NACT axillary imaging and clinicopathological data of patients who received NACT for primary breast cancer and underwent surgery. After NACT, accuracy of imaging modalities were evaluated through the comparison of pathologic lymph node (LN) status and imaging LN status. @*Results@#Fifty seven patients completed NACT and underwent surgery. Breast US was found to have a sensitivity of 61.1%, specificity of 57.7%, negative predictive value (NPV) of 68.2%, and positive predictive value (PPV) of 50.0%. For breast MRI, sensitivity was 58.3%, specificity 75.8%, NPV 71.4%, and PPV 63.6%. For US combined with MRI, sensitivity was 66.7%, specificity 54.5%, NPV 69.2%, and PPV 51.6%. The accuracy of imaging modalities was 59.1% for US, 68.4% for MRI, and 59.6% for US combined with MRI. @*Conclusion@#In breast cancer patients who received NACT, MRI showed a higher specificity, NPV, and PPV than US, although it had a lower sensitivity. However, due to the low accuracy, breast MRI alone is not sufficient to determine the extent of axillary surgery. Therefore, determining the extent of axillary surgery based on the results of intraoperative sentinel lymph node biopsy may be the right method for accurate staging.

Hyperglycemia during Adjuvant Chemotherapy as a Prognostic Factor in Breast Cancer Patients without Diabetes / 한국유방암학회지

Purpose@#Breast cancer treatments, including chemotherapy, administered in combination with glucocorticoids can induce hyperglycemia. This study aimed to investigate the effect of hyperglycemia during adjuvant chemotherapy on the prognosis of breast cancer patients without a known history of diabetes. @*Methods@#In this study, 936 patients who underwent breast cancer surgery from 2010 to 2015 were initially selected as participants. Chemotherapy-related hyperglycemia was defined as fasting plasma glucose levels ≥ 100 mg/dL or random blood glucose levels ≥ 140 mg/dL during 2 or more cycles of adjuvant chemotherapy. After dividing the patients into the euglycemia and hyperglycemia groups, univariate and multivariate analyses were performed, and survival outcomes were analyzed by propensity score matching. @*Results@#The mean age of the patients was 47.4 ± 7.7 years, and the median follow-up period was 70.1 months. Eighty-two patients (19.4%) were diagnosed as having hyperglycemia.There were significant differences between the euglycemia and hyperglycemia groups with respect to age, hypertension, body mass index, axillary surgery extents, nodal stage, and total steroid dosage. T stage, vascular invasion, and hyperglycemia were identified as prognostic factors of relapse-free survival (RFS). The 5-year RFS rates were 92.0% and 82.3% in the euglycemia and hyperglycemia groups, respectively, and there was a statistically significant difference between the 2 groups (p = 0.011). The 5-year overall survival rates were 94.6% and 92.0% in the euglycemia and hyperglycemia groups, respectively, showing no statistically significant difference between the 2 groups (p = 0.113). @*Conclusion@#These data suggest that hyperglycemia during adjuvant chemotherapy is a prognostic factor for RFS in breast cancer patients without diabetes.

Accuracy of Radiological Axillary Staging for Breast Cancer Patients with Neoadjuvant Chemotherapy

Purpose@#Neoadjuvant chemotherapy (NACT) in breast cancer patients has the advantage of decreasing related morbidities by reducing the extent of axillary surgery. However, it remains a controversy with regards to the appropriate extent of axillary lymph node dissection after NACT. Therefore, this study aims to investigate the accuracy of breast ultrasonography (US) and breast magnetic resonance imaging (MRI) to assess the axillary nodal status after NACT. @*Methods@#We reviewed pre- and post-NACT axillary imaging and clinicopathological data of patients who received NACT for primary breast cancer and underwent surgery. After NACT, accuracy of imaging modalities were evaluated through the comparison of pathologic lymph node (LN) status and imaging LN status. @*Results@#Fifty seven patients completed NACT and underwent surgery. Breast US was found to have a sensitivity of 61.1%, specificity of 57.7%, negative predictive value (NPV) of 68.2%, and positive predictive value (PPV) of 50.0%. For breast MRI, sensitivity was 58.3%, specificity 75.8%, NPV 71.4%, and PPV 63.6%. For US combined with MRI, sensitivity was 66.7%, specificity 54.5%, NPV 69.2%, and PPV 51.6%. The accuracy of imaging modalities was 59.1% for US, 68.4% for MRI, and 59.6% for US combined with MRI. @*Conclusion@#In breast cancer patients who received NACT, MRI showed a higher specificity, NPV, and PPV than US, although it had a lower sensitivity. However, due to the low accuracy, breast MRI alone is not sufficient to determine the extent of axillary surgery. Therefore, determining the extent of axillary surgery based on the results of intraoperative sentinel lymph node biopsy may be the right method for accurate staging.

Hyperglycemia during Adjuvant Chemotherapy as a Prognostic Factor in Breast Cancer Patients without Diabetes / 한국유방암학회지

Purpose@#Breast cancer treatments, including chemotherapy, administered in combination with glucocorticoids can induce hyperglycemia. This study aimed to investigate the effect of hyperglycemia during adjuvant chemotherapy on the prognosis of breast cancer patients without a known history of diabetes. @*Methods@#In this study, 936 patients who underwent breast cancer surgery from 2010 to 2015 were initially selected as participants. Chemotherapy-related hyperglycemia was defined as fasting plasma glucose levels ≥ 100 mg/dL or random blood glucose levels ≥ 140 mg/dL during 2 or more cycles of adjuvant chemotherapy. After dividing the patients into the euglycemia and hyperglycemia groups, univariate and multivariate analyses were performed, and survival outcomes were analyzed by propensity score matching. @*Results@#The mean age of the patients was 47.4 ± 7.7 years, and the median follow-up period was 70.1 months. Eighty-two patients (19.4%) were diagnosed as having hyperglycemia.There were significant differences between the euglycemia and hyperglycemia groups with respect to age, hypertension, body mass index, axillary surgery extents, nodal stage, and total steroid dosage. T stage, vascular invasion, and hyperglycemia were identified as prognostic factors of relapse-free survival (RFS). The 5-year RFS rates were 92.0% and 82.3% in the euglycemia and hyperglycemia groups, respectively, and there was a statistically significant difference between the 2 groups (p = 0.011). The 5-year overall survival rates were 94.6% and 92.0% in the euglycemia and hyperglycemia groups, respectively, showing no statistically significant difference between the 2 groups (p = 0.113). @*Conclusion@#These data suggest that hyperglycemia during adjuvant chemotherapy is a prognostic factor for RFS in breast cancer patients without diabetes.

Erratum: Basic Findings Regarding Breast Cancer in Korea in 2015: Data from a Breast Cancer Registry / 한국유방암학회지

This article was initially published on the Journal of Breast Cancer with a misspelled legend display in Figure 3. The postmenopause and premenopause should be changed with each other.

Basic Findings Regarding Breast Cancer in Korea in 2015: Data from a Breast Cancer Registry / 한국유방암학회지

The Korean Breast Cancer Society (KBCS) has established a nationwide breast cancer database using an online registration program in 1996. The present study aimed to analyze the basic findings and trends of breast cancer in Korea in 2015 using the data provided by the Korea Central Cancer Registry and the KBCS. In 2015, a total of 22,550 patients were newly diagnosed with breast cancer, of which 3,331 were carcinoma in situ cases and 19,219 were invasive cancer cases. The incidence rate of breast cancer in Korea has steadily increased since the nationwide database was established, and the crude rate and age-standardized rate including that of carcinoma in situ, were 88.1 and 66.0 cases per 100,000 women, respectively. In terms of age, the incidence of breast cancer was the highest in the 40–49-year-old age group (7,889 patients, 35.0%). With regard to surgical procedure, breast-conserving surgery was frequently performed (62.3%). However, the rate of mastectomy has been gradually increasing since 2012, that is, from 32.3% in 2014 to 36.1% in 2015. The rate of early breast cancer has continued to increase, and that of stages III and IV breast cancer was only 9.1% at the time of diagnosis. However, the 5-year survival rate of patients with carcinoma in situ from 2011 to 2015 was 92.3%, which was 14.4% higher than that from 1993 to 1995 (77.9%). Analysis of data from the nationwide registry of breast cancer will not only help to understand the characteristics of breast cancer in individuals in Korea, but will also significantly contribute to the treatment and research of breast cancer. Therefore, a high quality database for breast cancer in Korea must be established by further initiating registration project and establishing an objective legal basis.

Prognostic significance of intraoperative macroscopic serosal invasion finding when it shows a discrepancy in pathologic result gastric cancer

PURPOSE: Depth of wall invasion is an important prognostic factor in patients with gastric cancer, whereas the prognostic significance of intraoperative macroscopic serosal invasion (mSE) findings remain unclear when they show a discrepancy in pathologic findings. This study, therefore, assessed the prognostic significance of mSE. METHODS: Data from cohort of 2,835 patients with resectable gastric cancer who underwent surgery between 1990 and 2010 were retrospectively reviewed. RESULTS: The overall accuracy of mSE and pathologic results was 83.4%. The accuracy of mSE was 75.5% in pT2. On the other hand, the accuracy of pT3 dropped to 24.5%. According to mSE findings (+/-), the 5-year disease-specific survival (DSS) rate differed significantly in patients with pT2 (+; 74.2% vs. -; 92.0%), pT3 (+; 76.7% vs. -; 91.8%) and pT4a (+; 51.3% vs. -; 72.8%) (P < 0.001 each), but not in patients with T1 tumor. Multivariate analysis showed that mSE findings (hazard ratio [HR], 2.275; 95% confidence interval [CI], 1.148-4.509), tumor depth (HR, 6.894; 95% CI, 2.325-20.437), nodal status (HR, 5.206; 95% CI, 2.298-11.791), distant metastasis (HR, 2.881; 95% CI, 1.388-6.209), radical resection (HR, 2.002; 95% CI, 1.017-3.940), and lymphatic invasion (HR, 2.713; 95% CI, 1.424-5.167) were independent predictors of 5-year DSS rate. CONCLUSION: We observed considerable discrepancies between macroscopic and pathologic diagnosis of serosal invasion. However, macroscopic diagnosis of serosal invasion was independently prognostic of 5-year DSS. It suggests that because the pathologic results could not be perfect and the local inflammatory change with mSE(+) could affect survival, a combination of mSE(+/-) and pathologic depth may be predictive of prognosis in patients with gastric cancer.

Non-recurrent Laryngeal Nerve Identified During Robotic Thyroidectomy in a Patient with Papillary Thyroid Carcinoma / 대한내분비외과학회지

A non-recurrent laryngeal nerve is a rare anatomical variant that entails considerable risk for iatrogenic injury during thyroid surgery. We encountered a patient with a non-recurrent laryngeal nerve that went unnoticed on preoperative imaging but was discovered incidentally during robotic thyroidectomy. A 44 year old woman presented at our department with papillary thyroid microcarcinoma, diagnosed by ultrasonography-guided fine needle aspiration cytology. During robotic right thyroidectomy and central lymph node dissection, we could not detect any structure resembling the recurrent laryngeal nerve around the inferior thyroid artery. Thus, we suspected the existence of a non-recurrent laryngeal nerve, and successfully identified a nerve entering the larynx directly from the vagus nerve without recurring. A three-dimensional high magnification view via a robotic endoscope can aid thyroid surgeons to safely identify and preserve a non-recurrent laryngeal nerve.

The Prognostic Significance of the Metastatic Lymph Node Ratio in Patients with Papillary Thyroid Carcinoma / 대한내분비외과학회지

PURPOSE: Metastatic lymph node ratio (MLNR) is known as an important prognostic factor in many solid carcinomas; however, the role of MLNR in papillary thyroid carcinoma (PTC) is unclear. The purpose of this study was to determine whether MLNR has prognostic significance for recurrence in patients with pathological N1a PTC. METHODS: A retrospective analysis was conducted of 1,198 patients with PTC who underwent total thyroidectomy with central neck dissection between 2006 and 2011. Only patients with central lymph node metastasis were included in this study. Patients with lateral neck lymph node metastasis or extrathyroidal involvement were excluded. Finally, this study included 282 patients with N1a patients. MLNR was defined as the number of metastatic lymph nodes divided by the number of removed lymph nodes. RESULTS: Median age was 47.3 years (17~73 years). There were 209 female patients and 41 male patients, respectively. Median follow-up period was 53 months (36~114 months). Median value of MLNR was 0.36 (0.04~1.000). Of 250 patients, 20 patients (8.0%) developed recurrent disease. MLNR independently predicted PTC recurrence (odds ratio [OR], 6.385; 95% confidence interval [CI], 2.523-16.158; P 0.47 should be monitored closely for recurrence.

Clinical Significance of Blood Neutrophil-to-Lymphocyte Ratio in Patients with Papillary Thyroid Carcinoma / 대한내분비외과학회지

PURPOSE: The neutrophil-to-lymphocyte ratio (NLR) is a strong predictor of poor prognosis in patients with various types of cancer. To date, the utility of NLR for prediction of prognosis in thyroid cancer patients has not been studied. Therefore, the aim of our study was to determine whether NLR is associated with other prognostic factors of papillary thyroid carcinoma and predictive of recurrence. METHODS: We conducted a retrospective review of 367 patients who underwent thyroidectomy for papillary thyroid carcinoma from January 2005 to December 2007. We measured the white blood cell count including neutrophil and lymphocyte within one month preoperatively. The NLR was defined as the absolute neutrophil count divided by absolute lymphocyte count. Logistic regression analysis was applied for comparison of NLR with other prognostic factors, including tumor size, lymph node metastasis, multiplicity, extrathyroidal invasion, and TNM stage. We also determined the cut-off value of NLR with a prediction for recurrence. RESULTS: Median age of patients was 47 years (16~86 years) and the rate of papillary thyroid microcarcinoma was 65.7% (241/367 cases). Median follow-up period was 1,841 days (506~3,135 days). The median value of NLR was 1.68 (0.66~6.36). NLR was not related to any other prognostic factors of papillary thyroid carcinoma. The cut-off value of NLR for prediction of recurrence was 1.73, where the sensitivity was 66.7% and specificity was 69.8%. CONCLUSION: Patients with NLR equal to or higher than 1.73 showed significantly higher recurrence of papillary thyroid carcinoma. Further validation study should be conducted for clinical use of NLR as a prognostic marker.

Clinicopathological Relevance between Body Mass Index and Papillary Thyroid Carcinoma / 대한내분비외과학회지

PURPOSE: Obesity is a known risk factor for several cancers, including breast, colon, esophagus, kidney, uterus, and thyroid. Recent studies have reported that higher body mass index (BMI) is also associated with more advanced stage. The aim of this study was to investigate the clinicopathological relevance between BMI and papillary thyroid carcinoma (PTC). METHODS: A total of 798 patients surgically treated for PTC from January 2006 to June 2010 were included in this study. Medical records and pathologic reports were reviewed retrospectively. According to BMI, patients were divided into four groups: underweight (3.1%), normal (57.3%), overweight (31.6%), and obese (8.0%). Clinicopathological factors were analyzed and compared between normal and other groups. RESULTS: According to the results, 709 patients were women (89.0%) and mean age was 48.5 years; mean follow-up period was 1,721+/-464.2 days. In comparison between the normal and underweight groups, there was significantly more extra-thyroidal invasion [Odds ratio (OR) 3.923, P=0.006] in the underweight group. In the obese group, tumor size was significantly larger (OR 1.794, P=0.007). However, there was no significant difference between the normal and overweight group. CONCLUSION: In the obese group, tumor size was the only clinical significant factor between high BMI and PTC. Interestingly, more extra-thyroidal invasion was seen in the underweight group. To confirm this result, further studies with long-term follow-up and more patients are required.

Comparison of Learning Curves and Clinical Outcomes between Laparoscopy-assisted Distal Gastrectomy and Open Distal Gastrectomy

PURPOSE: Most stomach surgeons have been educated sufficiently in conventional open distal gastrectomy (ODG) but insufficiently in laparoscopy-assisted distal gastrectomy (LADG). We compared learning curves and clinical outcomes between ODG and LADG by a single surgeon who had sufficient education of ODG and insufficient education of LADG. MATERIALS AND METHODS: ODG (90 patients, January through September, 2004) and LADG groups (90 patients, June 2006 to June 2007) were compared. The learning curve was assessed with the mean number of retrieved lymph nodes, operation time, and postoperative morbidity/mortality. RESULTS: Mean operation time was 168.3 minutes for ODG and 183.6 minutes for LADG. The mean number of retrieved lymph nodes was 37.9. Up to about the 20th to 25th cases, the slope decrease in the learning curve for LADG was more apparent than for ODG, although they both reached plateaus after the 50th cases. The mean number of retrieved lymph nodes reached the overall mean after the 30th and 40th cases for ODG and LADG, respectively. For ODG, complications were evenly distributed throughout the subgroups, whereas for LADG, complications occurred in 10 (33.3%) of the first 30 cases. CONCLUSIONS: Compared with conventional ODG, LADG is feasible, in particular for a surgeon who has had much experience with conventional ODG, although LADG required more operative time, slightly more time to get adequately retrieved lymph nodes and more complications. However, there were more minor problems in the first 30 LADG than ODG cases. The unfavorable results for LADG can be overcome easily through an adequate training program for LADG.

Comparison of Learning Curves and Clinical Outcomes between Laparoscopy-assisted Distal Gastrectomy and Open Distal Gastrectomy

PURPOSE: Most stomach surgeons have been educated sufficiently in conventional open distal gastrectomy (ODG) but insufficiently in laparoscopy-assisted distal gastrectomy (LADG). We compared learning curves and clinical outcomes between ODG and LADG by a single surgeon who had sufficient education of ODG and insufficient education of LADG. MATERIALS AND METHODS: ODG (90 patients, January through September, 2004) and LADG groups (90 patients, June 2006 to June 2007) were compared. The learning curve was assessed with the mean number of retrieved lymph nodes, operation time, and postoperative morbidity/mortality. RESULTS: Mean operation time was 168.3 minutes for ODG and 183.6 minutes for LADG. The mean number of retrieved lymph nodes was 37.9. Up to about the 20th to 25th cases, the slope decrease in the learning curve for LADG was more apparent than for ODG, although they both reached plateaus after the 50th cases. The mean number of retrieved lymph nodes reached the overall mean after the 30th and 40th cases for ODG and LADG, respectively. For ODG, complications were evenly distributed throughout the subgroups, whereas for LADG, complications occurred in 10 (33.3%) of the first 30 cases. CONCLUSIONS: Compared with conventional ODG, LADG is feasible, in particular for a surgeon who has had much experience with conventional ODG, although LADG required more operative time, slightly more time to get adequately retrieved lymph nodes and more complications. However, there were more minor problems in the first 30 LADG than ODG cases. The unfavorable results for LADG can be overcome easily through an adequate training program for LADG.