Analysis of Characteristics and Risk Factors of Patients with Single Gastric Cancer and Synchronous Multiple Gastric Cancer among 14,603 Patients

Background/Aims

Synchronous multiple gastric cancer (SMGC) accounts for approximately 6% to 14% of gastric cancer (GC) cases. This study aimed to identify risk factors for SMGC.

Methods

A total of 14,603 patients diagnosed with GC were prospectively enrolled. Data including age, sex, body mass index, smoking, alcohol consumption, family history, p53 expression, microsatellite instability, cancer classification, lymph node metastasis, and treatment were collected. Risk factors were analyzed using logistic regression analysis between a single GC and SMGC.

Results

The incidence of SMGC was 4.04%, and that of early GC (EGC) and advanced GC (AGC) was 5.43% and 3.11%, respectively. Patients with SMGC were older (65.33 years vs 61.75 years, p<0.001) and more likely to be male. Lymph node metastasis was found in 27% of patients with SMGC and 32% of patients with single GC. Multivariate analysis showed that SMGC was associated with sex (male odds ratio [OR], 1.669; 95% confidence interval [CI], 1.223 to 2.278; p=0.001), age (≥65 years OR, 1.532; 95% CI, 1.169 to 2.008; p=0.002), and EGC (OR, 1.929; 95% CI, 1.432 to 2.600; p<0.001). Survival rates were affected by Lauren classification, sex, tumor size, cancer type, distant metastasis, and venous invasion but were not related to the number of GCs. However, the survival rate of AGC with SMGC was very high.

Conclusions

SMGC had unique characteristics such as male sex, older age, and EGC, and the survival rate of AGC, in which the intestinal type was much more frequent, was very good (Trial registration number: NCT04973631).

Sex-dependent different clinicopathological characterization of Epstein-Barr virus-associated gastric carcinoma: a large-scale study

BACKGROUND

Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) has been reported to account for approximately 5-16% of all GCs with good prognosis compared to EBV-negative GC. We evaluated the clinicopathological characteristics of EBVaGC including survival rate in South Korea.

METHODS

A total of 4,587 patients with GC who underwent EBV in situ hybridization (EBV-ISH) were prospectively enrolled at the Seoul National University Bundang Hospital from 2003 to 2021. Age, sex, smoking status, cancer type and stage, tumor size and location, histological type, molecular features and survival information were analyzed.

RESULTS

A total of 456 patients with GC (9.9%) were positive for EBV. The EBVaGC group displayed a higher proportion of males (P < 0.001), a predominant presence in the proximal stomach (P < 0.001), a higher proportion of undifferentiated cancer (P < 0.001), and a lower cancer stage (P = 0.004) than the EBV-negative group. Cox multivariate analyses revealed age (hazard ratio [HR] = 1.025, P < 0.001), tumor size (HR = 1.109, P < 0.001), and cancer stage (stage2 HR = 4.761, P < 0.001; stage3 HR = 13.286, P < 0.001; stage4 HR = 42.528, P < 0.001) as significant risk factors for GC-specific mortality, whereas EBV positivity was inversely correlated (HR = 0.620, P = 0.022). Furthermore, the EBVaGC group displayed statistically significant survival advantages over the EBV-negative cancer group in terms of both overall (P = 0.021) and GC-specific survival (P = 0.007) on the Kaplan-Meier survival curve. However, this effect was evident only in males.

CONCLUSIONS

EBVaGC patients showed better prognoses despite their association with proximal location and poorly differentiated histology in male, probably due to the difference in immunity between males and females.

Genomic and Transcriptomic Characterization of Gastric Cancer with Bone Metastasis

PURPOSE

Bone metastasis (BM) adversely affects the prognosis of gastric cancer (GC). We investigated molecular features and immune microenvironment that characterize GC with BM compared to GC without BM.

MATERIALS AND METHODS

Targeted DNA and whole transcriptome sequencing were performed using formalin-fixed paraffin-embedded primary tumor tissues (gastrectomy specimens) of 50 GC cases with distant metastases (14 with BM and 36 without BM). In addition, immunohistochemistry (IHC) for mucin-12 and multiplex IHC for immune cell markers were performed.

RESULTS

Most GC cases with BM had a histologic type of poorly cohesive carcinoma and showed worse overall survival (OS) than GC without BM (p < 0.05). GC with BM tended to have higher mutation rates in TP53, KDR, APC, KDM5A, and RHOA than GC without BM. Chief cell-enriched genes (PGA3, PGC, and LIPF), MUC12, MFSD4A, TSPAN7, and TRIM50 were upregulated in GC with BM compared to GC without BM, which was correlated with poor OS (p < 0.05). However, the expression of SERPINA6, SLC30A2, PMAIP1, and ITIH2 were downregulated in GC with BM. GC with BM was associated with PIK3/AKT/mTOR pathway activation, whereas GC without BM showed the opposite effect. The densities of helper, cytotoxic, and regulatory T cells did not differ between the two groups, whereas the densities of macrophages were lower in GC with BM (p < 0.05).

CONCLUSION

GC with BM had different gene mutation and expression profiles than GC without BM, and had more genetic alterations associated with a poor prognosis.

Social capital, food insecurity, and health outcomes in the US during the COVID-19 pandemic

AIMS

The purpose of this study was first, to investigate the harmful effects of food insufficiency on health outcomes - self-rated health (SRH) and self-assessed depressive symptoms - during the COVID-19 pandemic and, second, to test whether these effects fluctuated across the US in terms of state-level social capital.

METHODS

Data were drawn from the Census Household Pulse Survey (fielded between April 2020 and February 2021) consisting of community-dwelling American adults (N = 1.5M+). Social capital measures were taken from the 'Social Capital Project' sponsored by the US Congress. We estimated three-level mixed effects models to analyze multiple waves of repeated cross-sectional surveys.

RESULTS

Post-COVID-19 food insufficiency was significantly negatively associated with SRH and positively associated depression, adjusting for controls including food insufficiency prior to the onset of the pandemic. These relationships were also more pronounced in areas with higher aggregate social capital.

CONCLUSIONS

The health burdens of the new coronavirus disease have fallen disproportionately on the economically marginalized, as measured by food insufficiency. Contrary to the conventional literature, living in a state with a greater stock of social capital worsened its health effects.

The Clinicopathological Features of Mixed Carcinoma in 7,215 Patients with Gastric Cancer in a Tertiary Hospital in South Korea

Background/Aims

There are few reports regarding mixed carcinoma, defined as a mixture of glandular and poorly cohesive components, in patients with gastric cancer (GC). The aim of this study was to evaluate the proportion and characteristics of mixed carcinoma in GC patients.

Methods

A total of 7,215 patients diagnosed with GC at Seoul National University Bundang Hospital were enrolled from March 2011 to February 2020. GC was divided into four groups (well-moderately differentiated GC, poorly differentiated GC, poorly cohesive carcinoma, and mixed carcinoma). The proportion of each GC type and the clinicopathological features were analyzed and divided into early GC and advanced GC.

Results

The proportion of mixed carcinoma was 10.9% (n=787). In early GC, submucosal invasion was the most common in poorly differentiated (53.7%), and mixed carcinoma ranked second (41.1%). Mixed carcinoma showed the highest proportion of lymph node metastasis in early GC (23.0%) and advanced GC (78.3%). In advanced GC, the rate of distant metastasis was 3.6% and 3.9% in well-moderately differentiated GC and mixed carcinoma, respectively, lower than that in poorly differentiated GC (6.4%) and poorly cohesive carcinoma (5.7%), without statistical significance.

Conclusions

Mixed carcinoma was associated with lymph node metastasis compared to other histological GC subtypes. And it showed relatively common submucosal invasion in early GC, but the rates of venous invasion and distant metastasis were lower in advanced GC. Further research is needed to uncover the mechanism underlying these characteristics of mixed carcinoma (Trial registration number: NCT04973631).

Impact of Body Mass Index on Survival Depending on Sex in 14,688 Patients with Gastric Cancer in a Tertiary Hospital in South Korea

Background/Aims

The incidence and prognosis of gastric cancer (GC) shows sex difference. This study aimed to evaluate the effect of body mass index (BMI) on GC survival depending on sex.

Methods

The sex, age, location, histology, TNM stages, BMI, and survival were analyzed in GC patients from May 2003 to February 2020 at the Seoul National University Bundang Hospital.

Results

Among 14,688 patients, there were twice as many males (66.6%) as females (33.4%). However, under age 40 years, females (8.6%) were more prevalent than males (3.1%). Cardia GC in males showed a U-shaped distribution for underweight (9.6%), normal (6.4%), overweight (6.1%), obesity (5.6%), and severe obesity (9.3%) but not in females (p=0.003). Females showed decreased proportion of diffuse-type GC regarding BMI (underweight [59.9%], normal [56.8%], overweight [49.5%], obesity [44.8%], and severe obesity [41.7%]), but males did not (p<0.001). Both sexes had the worst prognosis in the underweight group (p<0.001), and the higher BMI, the better prognosis in males, but not females. Sex differences in prognosis according to BMI tended to be more prominent in males than in females in subgroup analysis of TNM stages I, II, and III and the operative treatment group.

Conclusions

GC-specific survival was affected by BMI in a sex-dependent manner. These differences may be related to genetic, and environmental, hormonal factors; body composition; and muscle mass (Trial registration number: NCT04973631).

Unifying principles of cryopreservation protocols for new plant materials based on alternative cryoprotective agents (cpas) and a systematic approach

This review addresses a frequently encountered problem of designing an effective cryopreservation procedure for new (not previously cryopreserved) or difficult plant materials. This problem hinders worldwide efforts of applying cryopreservation across a wide genetic base of wild and a number of cultivated plants. We review recent advances in modifications of routinely applied cryoprotective solutions (CPAs) and suggest a practical approach to protocol development which embraces the physiological complexity of plant tissues as well as a wide spectrum of behaviours under CPA treatment. We suggest that vegetative plant materials are classified into four categories based on their size, structure, and the response to osmotic and chemical stresses provoked by CPA mixtures of varied composition and concentration, including alternative osmoprotection and vitrification solutions. A number of up to 15 preset protocols designed specifically for each category is then applied to the material. The protocols resulting in the best regrowth are then combined into the optimized procedure. The main advantage of this system over a conventional "trial-and-error" search for working cryopreservation protocol is a minimal amount of starting materials required for the tests and a relatively accurate prediction of material behaviour under cryopreservation stress provided by the relatively few CPAs treatments. The unifying principles revealed by this approach could broaden a spectrum of wild species and materials which can be safely conserved by cryopreservation. Also anticipated is application of this approach to plant materials of biotechnological value as well as cultivars of agricultural and horticultural crops which do not respond well to standard protocols developed for their kind. doi.org/10.54680/fr23110110112.

Unifying principles of cryopreservation protocols for new plant materials based on alternative cryoprotective agents (cpas) and a systematic approach

This review addresses a frequently encountered problem of designing an effective cryopreservation procedure for new (not previously cryopreserved) or difficult plant materials. This problem hinders worldwide efforts of applying cryopreservation across a wide genetic base of wild and a number of cultivated plants. We review recent advances in modifications of routinely applied cryoprotective solutions (CPAs) and suggest a practical approach to protocol development which embraces the physiological complexity of plant tissues as well as a wide spectrum of behaviours under CPA treatment. We suggest that vegetative plant materials are classified into four categories based on their size, structure, and the response to osmotic and chemical stresses provoked by CPA mixtures of varied composition and concentration, including alternative osmoprotection and vitrification solutions. A number of up to 15 preset protocols designed specifically for each category is then applied to the material. The protocols resulting in the best regrowth are then combined into the optimized procedure. The main advantage of this system over a conventional "trial-and-error" search for working cryopreservation protocol is a minimal amount of starting materials required for the tests and a relatively accurate prediction of material behaviour under cryopreservation stress provided by the relatively few CPAs treatments. The unifying principles revealed by this approach could broaden a spectrum of wild species and materials which can be safely conserved by cryopreservation. Also anticipated is application of this approach to plant materials of biotechnological value as well as cultivars of agricultural and horticultural crops which do not respond well to standard protocols developed for their kind. doi.org/10.54680/fr23110110112.

Ammonium-free medium is critical for regeneration of shoot tips of the endangered species Pogostemon yatabeanus cryopreserved using droplet-vitrification

BACKGROUND

Pogostemon yatabeanus, synonym Dysophylla yatabeana, (Labiatae) is an endangered wild species in Korea. It has has a limited natural habitat and requires urgent conservation measures.

OBJECTIVE

To develop an efficient cryopreservation protocol using in vitro shoot tips to complement traditional conservation approaches in case seeds are unavailable, or insufficient in number for conservation programs.

MATERIALS AND METHODS

Node-cutting induced shoot tips of in vitro plants were produced and cryopreserved using a droplet-vitrification method following improvements in preculture, osmoprotection, vitrification solution (VS) and regrowth treatments. The starting protocol included preculture with 10% sucrose for 31 h, followed by osmoprotection with C4-35% (17.5% glycerol + 17.5% sucrose) for 40 min, and cryoprotection with A3-80% (33.3% glycerol + 13.3% DMSO + 13.3% EG + 20.1% sucrose) for 60 min on ice, cooling and warming using aluminum foil strips, and regrowth in MS hormone-free medium.

RESULTS

Shoot tips of Pogostemon yatabeanus were sensitive to the osmotic stress evidenced by low survival after step-wise preculture with 17.5% sucrose and cryopreservation without osmoprotection. Among VS tested, including PVS2, PVS3 and their alternatives, A3-80% on ice for 60 min resulted in the highest post-cryopreservation survival (80%) and regeneration (20%). Post-cryopreservation regeneration significantly improved (up to 73%) by incubation of cryopreserved shoot tips on ammonium-free medium followed by GA X₃-containing medium and medium without growth regulators.

CONCLUSION

Cryopreservation of in vitro shoot tips using droplet-vitrification was developed as a complementary conservation approach for D. yatabeana. Adjustment of medium composition during the recovery stage was important for regeneration of healthy plants from both cryoprotected-control and cryopreserved shoot tips.

The Incidence and Risk Factors for Metachronous Gastric Cancer in the Remnant Stomach after Gastric Cancer Surgery

Background/Aims

Less invasive surgical treatment is performed in East Asia to preserve postoperative digestive function and reduce complications such as postgastrectomy syndromes, but there is an issue of metachronous gastric cancer (GC) in the remaining stomach. This study aimed to analyze the incidence of metachronous GC and its risk factors in patients who had undergone partial gastrectomy.

Methods

A total of 3,045 GC patients who had undergone curative gastric partial resection at Seoul National University Bundang Hospital were enrolled and analyzed retrospectively for risk factors, including age, sex, smoking, alcohol, Helicobacterpylori status, family history of GC, histological type, and surgical method.

Results

Metachronous GC in the remaining stomach occurred in 35 of the 3,045 patients (1.1%) 23 in the distal gastrectomy group (18 with Billroth-I anastomosis, five with Billroth-II anastomosis), seven in the proximal gastrectomy (PG) group, and five in the pylorus-preserving gastrectomy (PPG) group. Univariate and multivariate Cox regression analyses showed that age ≥60 years (p=0.005) and surgical method used (PG or PPG, p<0.001) were related risk factors for metachronous GC, while male sex and intestinal type histology were potential risk factors.

Conclusions

Metachronous GC was shown to be related to older age and the surgical method used (PG or PPG). Regular and careful follow-up with endoscopy should be performed in the case of gastric partial resection, especially in patients with male sex and intestinal type histology as well as those aged ≥60 years undergoing the PG or PPG surgical method.

Strategies for controlling dog-mediated human rabies in Asia: using 'One Health' principles to assess control programmes for rabies

Over 99% of human rabies cases in endemic areas are transmitted by dogs. Without the elimination of dog rabies, it is not easy to reduce human rabies infection. Controlling dog rabies, especially in ownerless or free-roaming dogs, is critical if we are to decrease the rate of human rabies infection. There are several components in a strategy to eliminate dog-mediated rabies in Asia. Each government must make sure that rabies is either a reportable disease or a notifiable disease and enforce the reporting requirements accordingly. They must also focus on organising and operating special rabies control committees that work with relevant agencies under the 'One Health' banner. They should also implement a national rabies control programme that includes mass dog vaccination, laboratory-based surveillance, stable budget allocation, a rapidreporting system, management of dog populations, international cooperation, prevention of animal introductions from other countries, and risk assessment to analyse the programme's weaknesses. As several developed countries have shown, an effective rabies control strategy leads to rabies-free status. In the Republic of Korea, human rabies has not occurred since 2004, and there have not been any confirmed cases of dog rabies or cases of rabies in wild animals, including raccoon dogs, since 2014. The successful implementation of the key strategies used to eliminate rabies in the Republic of Korea will enable other Asian countries to eliminate dog-mediated human rabies.

Cryopreservation of Endangered Wild Species, Aster altaicus var. uchiyamae Kitam, Using Droplet-Vitrification Procedure

BACKGROUND

Aster altaicus var. uchiyamae Kitam is an endemic and endangered species in urgent need of a comprehensive conservation strategy.

OBJECTIVE

To develop an efficient cryopreservation protocol using in vitro shoot tips to complement traditional conservation approaches in case seeds are not available or insufficient for conservation programs.

METHODS

Shoot tips of in vitro plants were cryopreserved using a droplet-vitrification method following improvement of pre-culture, osmoprotection, vitrification solution (VS), unloading and post-culture treatments. The starting protocol included step-wise pre-culture with 10% and 17.5% sucrose for 55 h and 17 h, respectively, followed by osmoprotection with C4-35% (17.5% glycerol + 17.5% sucrose) for 30 min, and cryoprotection with B5-80% (40% glycerol + 40% sucrose) for 60 min.

RESULTS

Shoot tips of A. altaicus were found to be moderately sensitive to the osmotic stress. Pre-culture and osmoprotection were not critical for the regeneration of cryopreserved explants when either of these treatments was applied. Osmoprotection with C4-35% on ice for 60 min followed by cryoprotection with A3-80%, a modified and diluted PVS2, on ice for 60 min resulted in the highest (65.3%) regeneration of cryopreserved shoot tips. Among alternative VSs tested, A3-80% and B5-80% were superior to PVS2 and PVS3 used under the same conditions. Step-wise recovery of shoot tips on ammonium-free medium followed by GA₃-containing medium and medium without growth regulators were critical for the normal regeneration of both VS-treated and cryopreserved shoot tips.

CONCLUSIONS

Cryopreservation of in vitro shoot tips using droplet-vitrification was developed as a complementary conservation approach for A. altaicus. Adjustment of the composition of regrowth media depending on recovery stage was important for the regeneration of healthy plants from cryopreserved shoot tips.

[Laparoscopic Proximal Gastrectomy as a Surgical Treatment for Upper Third Early Gastric Cancer]

Recently, the incidence of upper third gastric cancer has increased, and with it the number of endoscopic submucosal dissection (ESD) procedures performed has been increasing. However, if ESD is not indicated or non-curable, surgical treatment may be necessary. In the case of lower third gastric cancer, it is possible to preserve the upper part of the stomach; however, in the case of upper third gastric cancer, total gastrectomy is still the standard treatment option, regardless of the stage. This is due to the complications associated with upper third gastric cancer, such as gastroesophageal reflux after proximal gastrectomy rather than oncologic problems. Recently, the introduction of the double tract reconstruction method after proximal gastrectomy has become one of the surgical treatment methods for upper third early gastric cancer. However, since there has not been a prospective comparative study evaluating its efficacy, the ongoing multicenter prospective randomized controlled trial (KLASS-05) comparing laparoscopic proximal gastrectomy with double tract reconstruction and laparoscopic total gastrectomy is expected to be important for determining the future of treatment of upper third early gastric cancer.

Is endoscopic surveillance necessary for patients who undergo total gastrectomy for gastric cancer?

There have been only a few reports investigating the clinical efficacy of follow-up endoscopy for detection of recurrent gastric cancer after total gastrectomy (TG). We reviewed the records of 747 patients undergoing TG from 2003 to 2012 and enrolled 267 patients (70 with early gastric cancer (EGC) and 197 with advanced gastric cancer (AGC)), who received one or more follow-up endoscopy and contrast abdominal computed tomography (CT) scan. We found no tumor recurrence in the 70 EGC patients during the mean follow-up periods of 42.1 ± 18 and 43.2 ± 19 months by endoscopy and contrast abdominal CT scan. In 197 AGC patients, 59 patients (29.8%) had confirmed tumor recurrence during mean follow-up periods of 40.5 ± 21 and 45.3 ± 22 months. The most common pattern of tumor recurrence was distant metastasis (n = 35) followed by peritoneal metastasis (n = 11). Among the other 13 cases with loco-regional recurrence, seven cases were regional lymph node metastases, four were anastomosis site recurrences, and two were duodenal stump and jejunal loop site recurrences. Three of the four cases of anastomosis site recurrence were found by both endoscopy and contrast abdominal CT scan; one case was missed by contrast abdominal CT scan. However, the two cases with duodenal stump and jejunal loop recurrences were detected by contrast abdominal CT scan only. An annual follow-up endoscopy for gastric cancer after TG might have a limited role in the detection of tumor recurrence, especially in patients with EGC. Contrast abdominal CT scan may be sufficient as a follow-up method for recurrent gastric cancer after TG.

Dynamic Changes in Helicobacter pylori Status Following Gastric Cancer Surgery

Background/Aims

Helicobacter pylori eradication is recommended in patients with early gastric cancer. However, the possibility of spontaneous regression raises a question for clinicians about the need for "retesting" postoperative H. pylori status.

Methods

Patients who underwent curative gastrectomy at Seoul National University Bundang Hospital and had a positive H. pylori status without eradication therapy at the time of gastric cancer diagnosis were prospectively enrolled in this study. H. pylori status and atrophic gastritis (AG) and intestinal metaplasia (IM) histologic status were assessed pre- and postoperatively.

Results

One hundred forty patients (mean age, 59.0 years; 60.7% male) underwent subtotal gastrectomy with B-I (65.0%), B-II (27.1%), Roux-en-Y (4.3%), jejunal interposition (0.7%), or proximal gastrectomy (4.3%). Preoperative presence of AG (62.9%) and IM (72.9%) was confirmed. The mean period between surgery and the last endoscopic follow-up was 38.0±25.6 months. Of the 140 patients, 80 (57.1%) were found to be persistently positive for H. pylori, and 60 (42.9%) showed spontaneous negative conversion at least once during follow-up. Of these 60 patients, eight (13.3%) showed more complex postoperative dynamic changes between negative and positive results. The spontaneous negative conversion group showed a trend of having more postoperative IM compared to the persistent H. pylori group.

Conclusions

A high percentage of spontaneous regression and complex dynamic changes in H. pylori status were observed after partial gastrectomy, especially in individuals with postoperative histological IM. It is better to consider postoperative eradication therapy after retesting for H. pylori.

Actual 5-Year Nutritional Outcomes of Patients with Gastric Cancer

Purpose

In this study, we aimed to evaluate the rarely reported long-term nutritional results of patients with gastric cancer after curative gastrectomy.

Materials and Methods

We retrospectively reviewed the prospectively collected medical records of 658 patients who underwent radical gastrectomy with curative intent for gastric cancer from January 2008 to December 2009 and had no recurrences. All patients were followed for 5 years. Nutritional statuses were assessed using measurements of body weight, serum hemoglobin, total lymphocyte count (TLC), protein, albumin, cholesterol, and nutritional risk index (NRI).

Results

Patients who underwent total gastrectomy had lower body weights, hemoglobin, protein, albumin, and cholesterol levels. TLC and NRI valued after the first postoperative year (P<0.05), and lower hemoglobin and NRI valued during the fifth postoperative year than patients who underwent distal gastrectomy (P<0.05). Patients who received adjuvant chemotherapy after gastrectomy had lower hemoglobin, protein, albumin, and cholesterol levels. TLC and NRI valued during the first postoperative year, than those who underwent gastrectomy only (P<0.05). Regarding post-distal gastrectomy reconstruction, those who underwent Roux-en-Y had lower cholesterol levels than did those who underwent Billroth-I and Billroth-II reconstruction at the first and fifth years after gastrectomy, respectively (P<0.05).

Conclusions

Patients undergoing total or distal gastrectomy with Roux-en-Y anastomosis or adjuvant chemotherapy after surgery should be monitored carefully for malnutrition during the first postoperative year, and patients undergoing total gastrectomy should be monitored for malnutrition and anemia for 5 years.

Proposal of a new stage grouping of gastric cancer for TNM classification: International Gastric Cancer Association staging project

BACKGROUND

The current AJCC staging system for gastric cancer (AJCC7) incorporated several major revisions to the previous edition. The T and N categories and the stage groups were newly defined, and adenocarcinoma of the esophagogastric junction (EGJ) was reclassified and staged according to the esophageal system. Studies to validate these changes showed inconsistent results. The International Gastric Cancer Association (IGCA) launched a project to support evidence-based revisions to the next edition of the AJCC staging system.

METHODS

Clinical and pathological data on patients who underwent curative gastrectomy at 59 institutions in 15 countries between 2000 and 2004 were retrospectively collected. Patients lost to follow-up within 5 years of surgery were excluded. Patients treated with neoadjuvant therapy were excluded. The data were analyzed in total, and separately by region of treatment.

RESULTS

Of 25,411 eligible cases, 84.8 % were submitted from 24 institutions of Japan and Korea, 6.4 % from other Asian countries, and 8.8 % from 29 Western institutions. The T and N categories of AJCC7 clearly stratified the patient survival. Patients with pN3a and pN3b showed distinct prognosis in all regions, and by introducing pN3a and pN3b into a cluster analysis, we established a new stage grouping with better stratification than AJCC7, especially among stage III subgroups. Survival of Siewert type 2 and 3 EGJ tumors was better stratified by this IGCA stage grouping than by either esophageal or gastric scheme of AJCC7.

CONCLUSIONS

For the next revision of AJCC classification, we propose a new stage grouping based on a large, worldwide data collection.

Comparison between Resectable Helicobacter pylori-Negative and -Positive Gastric Cancers

BACKGROUND/AIMS

Controversy exists regarding the characteristics of Helicobacter pylori infection-negative gastric cancer (HPIN-GC). The aim of this study was to evaluate clinicopathologic features of HPIN-GC compared to H. pylori infection-positive gastric cancer (HPIP-GC) using a comprehensive analysis that included genetic and environmental factors.

METHODS

H. pylori infection status of 705 resectable gastric cancer patients was determined by the rapid urease test, testing for anti-H. pylori antibodies, histologic analysis and culture of gastric cancer tissue samples, and history of H. pylori eradication. HPIN-GC was defined as gastric cancer that was negative for H. pylori infection based on all five methods and that had no evidence of atrophy in histology or serology.

RESULTS

The prevalence of HPIN-GC was 4% (28/705). No significant differences with respect to age, sex, smoking, drinking, family history of gastric cancer or obesity were observed between the two groups. HPIN-GC tumors were marginally more likely to involve the cardia (14.3% for HPIN-GC vs 5.3% for HPIP-GC, p=0.068). The Lauren classification, histology, and TNM stage did not differ according to H. pylori infection status. Microsatellite instability was not different between the two groups, but p53 overexpression in HPIN-GC was marginally higher than in HPIP-GC (56.0% for HPIN-GC vs 37.0% for HPIP-GC, p=0.055).

CONCLUSIONS

The prevalence of HPIN-GC was extremely low, and its clinicopathologic characteristics were similar to HPIP-GC.

The clinical characteristics of pleural effusion in scrub typhus

Background

The aim of this study is to identify the factors associated with the occurrence of pleural effusion and to investigate the characteristics of pleural effusion in scrub typhus.

Methods

We conducted a retrospective analysis of the medical records of scrub typhus patients between January 2004 and December 2011 at Chosun University Hospital in South Korea. A total of 445 scrub typhus patients were divided into the following two groups: without (n = 352) or with pleural effusion (n = 93). The data of 18 scrub typhus patients who underwent thoracentesis were summarized.

Results

Multivariate analysis demonstrated that the following factors were associated with the occurrence of pleural effusion in scrub typhus: older age (odds ratio [OR] = 1.029, P = 0.037, confidence interval [CI] = 1.002–1.056); male gender (OR = 1.924, P = 0.020, CI = 1.109–3.340); presence of heart failure (OR = 2.628, P = 0.039, CI = 1.052–6.565); and lower albumin (OR = 0.107, P ≤ 0.001, CI = 0.058–0.196). Most pleural effusion presentations were bilateral (88 %) and small (91 %). The effusion had transudate characteristics in 7 patients and exudate characteristics in 11 patients based on Light’s criteria.

Conclusions

This study provided the first data regarding the following four independent risk factors associated with the occurrence of pleural effusion: older age; male gender; the presence of heart failure; and lower albumin. The pleural effusion presentations in scrub typhus patients were bilateral and small in most cases, with transudate and/or exudate characteristics.

Relation between the Change in Mean Platelet Volume and Clopidogrel Resistance in Patients Undergoing Percutaneous Coronary Intervention

We aimed to determine the association between the change in mean platelet volume (MPV) over time and aspirin/ clopidogrel resistance in patients undergoing percutaneous coronary intervention (PCI). The MPV and platelet function were analysed in 302 patients who underwent PCI. MPV changes were associated with increased aspirin reaction units (ARU, r = 0.114; P = 0.047), increased P2Y12 reaction units (PRU, r = 0.193; P = 0.001), and decreased P2Y12% inhibition (PI%, r = - 0.273; P < 0.001). The group with increasing MPV values showed significantly higher PRU values and lower PI% compared with the group with decreasing MPV values (222.5 ± 73.9 vs. 195.6 ± 63.7 PRU, P = 0.001; 24.1 ± 21.0 vs. 32.8 ± 18.5 PI%, P < 0.001, respectively). The clopidogrel resistant group (≥235 PRU or ≤15% of PI%) showed a significantly higher positive change in MPV (ΔMPV) values than the clopidogrel responder group (0.53 ± 0.78 vs. 0.13 ± 0.69 fL, P < 0.001). When the ΔMPV cut-off level was set at 0.20 fL using the receiver operating characteristic curve, the sensitivity and specificity for differentiating between the clopidogrel resistant and responder groups were 72.6% and 59.3%, respectively. After adjusting for traditional risk factors, the odds ratio in the clopidogrel resistant group with ΔMPV ≥0.2 fL was 4.10 (95% confidence interval; 1.84-9.17). In conclusion, ΔMPV was associated with PRU and PI%; a positive ΔMPV was an independent predictive marker for clopidogrel resistance after PCI.

Nodular Fasciitis of the Chest in a Young Woman

Nodular fasciitis is a benign reactive proliferation that usually involves the deep fascia. Although it is relatively common in the adult population, it is often misdiagnosed as sarcoma due to its rapid growth and pathological features. It rarely presents as a chest wall tumor in young patients. Here, we report a case of nodular fasciitis involving the chest wall of an 18-year-old woman and its surgical management. This case underscores the need to consider nodular fasciitis in the differential diagnosis of chest wall tumors in young patients.

POST-HARVEST EMBRYO DEVELOPMENT IN GINSENG SEEDS INCREASES DESICCATION SENSITIVITY AND NARROWS THE HYDRATION WINDOW FOR CRYOPRESERVATION

BACKGROUND

Despite its self-pollinating characteristics, Korean ginseng germplasm is mainly maintained in clonal gene banks as there is no defined approach to the long-term conservation of its seed, including the most appropriate stage of embryo development for storage.

OBJECTIVE

The aim of this study was to reveal the effect of embryo development on desiccation tolerance and cryopreservation success in ginseng seeds.

MATERIALS AND METHODS

Seeds of Korean ginseng (Panax ginseng C.A. Meyer) at three post-harvest stages (immediately after harvesting and following treatments to enable internal growth of the embryo) were desiccated and cryopreserved.

RESULTS

The hydration window for the >80% dehiscence and germination of cryopreserved ginseng seeds varied with embryo developmental stage: 3-9% moisture content (MC) for both unpulped and undehisced seeds when the embryo was 0.1 the length of the endosperm, 7-10% MC for dehisced seeds (0.5 embryo:endosperm) and 9-11% MC for seeds with fully developed embryos (0.9 embryo:endosperm). Whilst dried (4-8% moisture content) and undehisced seeds within fruits (unpulped seeds) lost more than half their viability during 1 year's storage at room temperature, cryopreservation enabled germination levels of c. 90%. Overall, 432 accessions of Korean ginseng landraces have been cryopreserved using undehisced seeds with or without fruits.

CONCLUSION

Post-harvest treatment of Korean ginseng seeds to enable embryo development decreases tolerance of very low MCs, and thus narrows the hydration window for cryopreservation. Fresh-harvested and unpulped seeds that have been dried to c. 5% MC are recommended for long-term cryogenic storage.

Relationship between body mass index and the risk of early gastric cancer and dysplasia regardless of Helicobacter pylori infection

BACKGROUND

Obesity is known to be associated with an increased risk of gastric cardia cancer but not with noncardia cancer. In terms of gastric dysplasia, few studies have evaluated its relationship with obesity. In addition, no study on the relationship between obesity and the risk of gastric cancer has analyzed the status of Helicobacter pylori infection.

METHODS

A case-control study was designed to investigate the relationship between obesity and the risk of gastric cancer and dysplasia adjusted for the status of H. pylori infection in Koreans. Nine hundred ninety-eight gastric cancer patients, 313 gastric dysplasia patients, and 1,288 subjects with normal endoscopic findings were included.

RESULTS

As gender differences could be the largest confounding factor, the risk of gastric cancer and dysplasia with an increasing body mass index (BMI) was analyzed in men and women, separately, and was adjusted for age, smoking, drinking, family history of gastric cancer, H. pylori infection, atrophic gastritis, intestinal metaplasia, and serum pepsinogen I/pepsinogen II ratio. Obesity (BMI 25 kg/m(2) or greater but less than 30 kg/m(2)) was associated with increased risk of early gastric cancer [adjusted odds ratio (aOR) 1.657; 95 % confidence interval (CI) 1.086-2.528; P = 0.019] and well or moderately differentiated adenocarcinoma (aOR 1.566; 95 % CI 1.011-2.424; P = 0.044) compared with normal BMI status (BMI < 23 kg/m(2)) in men. Obesity was related to gastric dysplasia (aOR 2.086; 95 % CI 1.011-4.302; P = 0.047) in women.

CONCLUSIONS

The effect of obesity on gastric cancer showed a gender difference. That is, in men it was related to increased risk of early gastric cancer and well or moderately differentiated adenocarcinoma, but it was associated with gastric dysplasia in women regardless of H. pylori infection in Korea. Further research into this difference is necessary.

Clinical Relevance of the Tumor Location-Modified Lauren Classification System of Gastric Cancer

Purpose

The Lauren classification system is a very commonly used pathological classification system of gastric adenocarcinoma. A recent study proposed that the Lauren classification should be modified to include the anatomical location of the tumor. The resulting three types were found to differ significantly in terms of genomic expression profiles. This retrospective cohort study aimed to evaluate the clinical significance of the modified Lauren classification (MLC).

Materials and Methods

A total of 677 consecutive patients who underwent curative gastrectomy from January 2005 to December 2007 for histologically confirmed gastric cancer were included. The patients were divided according to the MLC into proximal non-diffuse (PND), diffuse (D), and distal non-diffuse (DND) type. The groups were compared in terms of clinical features and overall survival. Multivariate analysis served to assess the association between MLC and prognosis.

Results

Of the 677 patients, 48, 358, and 271 had PND, D, and DND, respectively. Their 5-year overall survival rates were 77.1%, 77.7%, and 90.4%. Compared to D and PND, DND was associated with significantly better overall survival (both P<0.01). Multivariate analysis showed that age, differentiation, lympho-vascular invasion, T and N stage, but not MLC, were independent prognostic factors for overall survival. Multivariate analysis of early gastric cancer patients showed that MLC was an independent prognostic factor for overall survival (odds ratio, 5.946; 95% confidence intervals, 1.524~23.197; P=0.010).

Conclusions

MLC is prognostic for survival in patients with gastric adenocarcinoma, in early gastric cancer. DND was associated with an improved prognosis compared to PND or D.

CRYOPRESERVATION OF SWEET POTATO SHOOT TIPS USING A DROPLET-VITRIFICATION PROCEDURE

BACKGROUND

Sweet potato is a staple food worldwide, but a problematic species in terms of long term storage, as it is not suitable for germplasm conservation.

OBJECTIVE

This study aimed to develop cryopreservation protocols for sweet potato shoot tips based on a droplet-vitrification procedure.

METHODS

As a standard procedure, sweet potato shoot tips were precultured in a liquid MS medium supplemented with 10% sucrose (S-10%) and 17.5% sucrose (S-17.5%) for 31 and 17 h, respectively. They were then osmoprotected with C4-35% (17.5% glycerol + 17.5% sucrose) for 50 min and cryoprotected with PVS3 (50% glycerol + 50% sucrose) for 60 min. A set of experiments was designed to investigate critical factors, i.e. stepwise sucrose preculture, osmoprotection, cryoprotection with PVS2- and PVS3-based vitrification solutions, and their combinational effect, as well as temperature alteration through placement in a cooling/rewarming container.

RESULTS

Sucrose preculture was determined to be necessary for the adaptation of sweet potato shoot tips to cryoprotection with PVS3, and the highest post-thaw (LN) regeneration rate was observed in a preculture with S-10% for 31 h → S-17.5% for 17 h (19.0%). The effect of one-step or two-step osmoprotection was not significant on survival or regeneration of either the cryoprotected-control (LNC) or LN shoot tips. Responses of sweet potato shoot tips to osmoprotection and cryoprotection were linked to the level of sucrose preculture. The use of alumimium foil strips (droplet-vitrification) resulted in significantly higher LN survival (89.8%) and regeneration (19.0%), compared to those using cryovials (vitrification, 67.2% and 0%, respectively). LN regeneration increased by 67.5% when cryopreserved shoot tips were transferred to a new postculture medium.

CONCLUSIONS

This study demonstrates that the combination of stepwise sucrose preculture with a higher final concentration (up to 17.5%), cryoprotection with PVS3 and cooling with foil strip is crucial to the regeneration of LN sweet potato shoot tips.

Successful Delivery Following Staphylococcus aureus Bacteremia after In Vitro Fertilization and Embryo Transfer

A 30-year-old, 16-week primipara woman visited with complaints of lower back pain over the past 3 weeks. She had a history of ultrasound-guided transvaginal oocyte retrieval for in vitro fertilization (IVF) 14 weeks earlier. Lumbar spine magnetic resonance imaging showed infectious spondylitis and the results of blood and spinal biopsy cultures showed Staphylococcus aureus. Intravenous cefazolin was continued for 6 weeks, and 4 months later, she delivered a healthy girl. This is the first reported case of successful term delivery following S. aureus bacteremia with vertebral osteomyelitis after IVF and embryo transfer. It should be considered that S. aureus bacteremia can be a serious complication of IVF.

Short-term effect of gastric resection on circulating levels of ghrelin, peptide YY3-36 and obestatin in patients with early gastric cancer

The short-term responses of gut hormones and the compensative interaction during a one-week period after subtotal gastrectomy in early gastric cancer (EGC) patients were assessed. Previous studies have reported gut hormonal changes after Roux-en-Y gastric bypass surgery. Blood samples were collected from 40 patients with EGC preoperatively, at 1 h after gastric resection, and on postoperative day (POD) 1, 3, and 7. Levels of active ghrelin, total ghrelin, obestatin, and PYY3-36 were measured. Total ghrelin level rapidly reached a nadir of 69.1%, while active ghrelin level had increased to 135.5% at 1 h after resection. Then, both returned to preoperative level. On the contrary, active/total ghrelin reached its nadir quickly at 1 h after resection and had returned to the preoperative level by POD 3. The nadir PYY3-36 level was 71.4% on POD 1, followed by a gradual recovery, and had increased to 116.5% by POD 7. The same pattern was observed for obestatin. Active ghrelin/obestatin showed an increase on POD 1 while total ghrelin/obestatin showed a decrease on POD 3. Then, both returned to preoperative level. These results suggest that a rapid interactive compensatory mechanism of gut hormones does exist in the remnant gastrointestinal tract after abrupt changes in the production reservoir in nonobese people.

The relevance of biopsy in tuberculosis patients without human immunodeficiency virus infection

Although chronic granulomatous inflammation (CGI) with concomitant caseous necrosis (CN) is a characteristic histological feature of tuberculosis (TB), few studies have investigated its frequency or various pathologic findings. The medical records of 227 human immunodeficiency virus (HIV) -negative, culture-positive TB patients who underwent biopsy were studied. After the frequency of characteristic pathological findings of TB was determined, a pathologist reanalyzed the pathological findings with particular focus on necrosis and reclassified CGI, CN, or possible CN into possible TB pathologic findings. The initial biopsy interpretation revealed that 63 (34.8%) of 181 patients with pulmonary TB had caseating granulomas, 36 (19.9%) patients had only CGI, and 6 (3.3%) patients had only CN. Among 46 patients with extrapulmonary TB, 16 (34.8%) patients had only caseating granulomas, and 14 (30.4%) patients had only CGI. More patients who underwent percutaneous lung biopsy had CGI or CN (76.3%) than patients who underwent transbronchial lung biopsy (53.6%). The reanalysis confirmed all CN cases identified by the first interpretation, and 20 (95.2%) of 21 non-CN cases were reclassified as possible CN. Ten cases (three pulmonary and seven extrapulmonary) were reclassified as possible TB pathologic findings from just necrosis. Caseating granuloma was present in only one-third of TB cases. Even in cases where only necrosis was identified, CN may be present.

The prognostic value of pretreatment of systemic inflammatory responses in patients with urothelial carcinoma undergoing radical cystectomy

Background:

Systemic inflammatory response (SIR) is important in the relationship between the tumour, the host, and outcome in cancer patients. However, limited data exist regarding the prognostic significance of SIR in bladder cancer. We investigate the utility of pretreatment SIR in patients with urothelial carcinoma undergoing radical cystectomy.

Methods:

The study cohort consisted of 419 patients with a median follow-up of 37.7 months. The SIRs used for each described prognostic nomogram are consistent with previously published data: C-reactive protein, albumin, white cell count, neutrophil count, lymphocyte count, and platelet count. Primary end point was disease-specific survival (DSS) and overall survival (OS) after surgery. Cox regression models were used to determine the time to disease-specific and overall mortality. Multivariate regression coefficients of the predictors were used to develop nomograms for predicting 5-year DSS and OS probability.

Results:

Multivariate Cox regression analyses revealed that albumin, lymphocyte count, and platelet count were significantly associated with a significantly increased risk for death from bladder cancer. The nomograms including each index were developed to predict the probability of 5-year DSS and OS after radical cystectomy. The C statistics were 77.8% and 77.3%, respectively, and exceeded the 2002 AJCC (72.0% and 70.3%, respectively). In the decision curve analyses, the nomograms including SIR demonstrated higher net benefit gains compared with the models without SIR.

Conclusions:

Cellular components of SIR have better prognostic values compared with acute-phase protein in patients undergoing radical cystectomy for bladder cancer.

A lazy learning-based QSAR classification study for screening potential histone deacetylase 8 (HDAC8) inhibitors

Histone deacetylases 8 (HDAC8) is an enzyme repressing the transcription of various genes including tumour suppressor gene and has already become a target of human cancer treatment. In an effort to facilitate the discovery of HDAC8 inhibitors, two quantitative structure-activity relationship (QSAR) classification models were developed using K nearest neighbours (KNN) and neighbourhood classifier (NEC). Molecular descriptors were calculated for the data set and database compounds using ADRIANA.Code of Molecular Networks. Principal components analysis (PCA) was used to select the descriptors. The developed models were validated by leave-one-out cross validation (LOO CV). The performances of the developed models were evaluated with an external test set. Highly predictive models were used for database virtual screening. Furthermore, hit compounds were subsequently subject to molecular docking. Five hits were obtained based on consensus scoring function and binding affinity as potential HDAC8 inhibitors. Finally, HDAC8 structures in complex with five hits were also subjected to 5 ns molecular dynamics (MD) simulations to evaluate the complex structure stability. To the best of our knowledge, the NEC classification model used in this study is the first application of NEC to virtual screening for drug discovery.

The relevance of biopsy in tuberculosis patients without human immunodeficiency virus infection

Although chronic granulomatous inflammation (CGI) with concomitant caseous necrosis (CN) is a characteristic histological feature of tuberculosis (TB), few studies have investigated its frequency or various pathologic findings. The medical records of 227 human immunodeficiency virus (HIV) -negative, culture-positive TB patients who underwent biopsy were studied. After the frequency of characteristic pathological findings of TB was determined, a pathologist reanalyzed the pathological findings with particular focus on necrosis and reclassified CGI, CN, or possible CN into possible TB pathologic findings. The initial biopsy interpretation revealed that 63 (34.8%) of 181 patients with pulmonary TB had caseating granulomas, 36 (19.9%) patients had only CGI, and 6 (3.3%) patients had only CN. Among 46 patients with extrapulmonary TB, 16 (34.8%) patients had only caseating granulomas, and 14 (30.4%) patients had only CGI. More patients who underwent percutaneous lung biopsy had CGI or CN (76.3%) than patients who underwent transbronchial lung biopsy (53.6%). The reanalysis confirmed all CN cases identified by the first interpretation, and 20 (95.2%) of 21 non-CN cases were reclassified as possible CN. Ten cases (three pulmonary and seven extrapulmonary) were reclassified as possible TB pathologic findings from just necrosis. Caseating granuloma was present in only one-third of TB cases. Even in cases where only necrosis was identified, CN may be present.

Helicobacter pylori and Molecular Markers as Prognostic Indicators for Gastric Cancer in Korea

Background:

The prognosis of H. pylori infection-negative gastric cancer (HPIN-GC) has been rarely investigated. Applying a strict definition of H. pylori status, the prognosis and molecular prognostic markers in HPIN-GC were evaluated.

Methods:

A combination of multiple methods was carried out to strictly evaluate H. pylori infection in gastric cancer (GC) patients between June 2003 and October 2012 at Seoul National University Bundang Hospital. H. pylori infection was defined as negative if histology, a rapid urease test, culturing, serology and history of H. pylori eradication were all negative. Patients with severe gastric atrophy by the serum pepsinogen test or histology were assumed to have had a previous H. pylori infection. Epstein-Barr virus (EBV) in situ hybridization, PCR-based microsatellite instability (MSI) testing, and p53 immunohistochemistry were performed.

Results:

Compared to 509 H. pylori infection-positive gastric cancer (HPIN-PC) patients, 24 HPIN-GC patients showed a significantly higher frequency of cardia location (P=0.013), and the depth of invasion in HPIN-GC was more advanced, although there was no statistical significance (pT3-pT4, 37.5% for HPIN-GC vs. 28.5% for HPIP-GC, P=0.341). In multivariate analysis, depth of invasion and lymph node metastasis were identified as the most important prognostic factors for relapse-free survival and overall survival (P<0.001). However, the status of H. pylori infection was not an independent prognostic factor for relapse-free survival and overall survival. The positivity of EBV in both groups was low, and the survivals according to MSI and p53 status in HPIN-GC patients were not significantly different.

Conclusions:

The status of H. pylori infection was not a prognostic factor for survival in GC patients when applying the strict definition of H. pylori infection. The prognostic implication of MSI and p53 on survival in HPIN-GC patients was not clear.

Prediction of pathological complete response of breast cancer patients undergoing neoadjuvant chemotherapy: usefulness of breast MRI computer-aided detection

OBJECTIVE

To evaluate the usefulness of MR computer-aided detection (CAD) in patients undergoing neoadjuvant chemotherapy for prediction of the pathological complete response of tumours.

METHODS

148 patients with breast cancer (mean age, 47.3 years; range, 29-72 years) who underwent neoadjuvant chemotherapy were included in our study. They underwent MRI before and after neoadjuvant chemotherapy, and we reviewed the pathological result as the gold standard. The computer-generated kinetic features for each lesion were recorded, and the features analysed included "threshold enhancement" at 50% and 100% minimum thresholds; degree of initial peak enhancement; and enhancement profiles comprising lesion percentages of washout, plateau and persistent enhancement. The final pathological size and character of tumours were correlated with post-chemotherapy mammography, ultrasonography and MR CAD findings. Kruskal-Wallis test and intraclass correlation coefficient were used to analyse the findings.

RESULTS

We divided the 148 patients into complete pathological response and non-complete pathological response groups. A complete pathological response was defined as no histopathological evidence of any residual invasive cancer cells in the breast or axillary lymph nodes. 39 patients showed complete pathological response, and 109 patients showed non-complete pathological response. Between enhancement profiles of MR CAD, plateau proportion of tumours was significantly correlated with the pathological response of tumours (mean proportion of plateau on complete pathological response group was 27%, p = 0.007).

CONCLUSION

When plateau proportion of tumours is high, we can predict non-complete pathological response of neoadjuvant chemotherapy.

ADVANCES IN KNOWLEDGE

MR CAD can be a useful tool for the assessment of response to neoadjuvant chemotherapy and prediction of pathological results.

Assessment of extent of breast cancer: comparison between digital breast tomosynthesis and full-field digital mammography

AIM

To compare the accuracy of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) in preoperative assessment of local extent of breast cancer.

MATERIALS AND METHODS

Lesion sizes of breast cancers on DBT and FFDM images were independently evaluated by breast radiologists. Each lesion was flagged as either mis-sized or not depending on whether the assessment of size at imaging was within 1 cm of the lesion size at surgery. Additional analyses were made by mammographic parenchymal density and by lesion size, using 2 cm as the boundary to separate the two subgroups. Statistical comparisons were performed using a repeated measures linear model on the percent mis-sized. P-values < 0.05 were considered statistically significant.

RESULTS

The dataset included 173 malignant breast lesions (mean size 23.8 mm, 43% of lesions were ≤2 cm in size) in 169 patients, two-thirds of which had heterogeneously or extremely dense breasts. Overall, the percentage of lesions mis-sized at DBT was significantly lower than at FFDM (19% versus 29%, p = 0.003). There was significantly less mis-sizing at DBT in both heterogeneously dense breasts (11.1% difference between DBT and FFDM, p = 0.016) and extremely dense breasts (15.8% difference, p = 0.024). DBT also had significantly less mis-sizing than FFDM in the subgroup of lesions that were ≤2 cm in size (14.7% difference, p = 0.005).

CONCLUSION

DBT was significantly superior to FFDM for the evaluation of lesion size overall, and specifically for small lesions and for lesions in dense breasts. The superiority of DBT versus FFDM increased with parenchymal density.

Type-specific diagnosis and evaluation of longitudinal tumor extent of borrmann type IV gastric cancer: CT versus gastroscopy

Objective

To compare the accuracy of computed tomography (CT) with that of gastroscopy for the extent of evaluation of longitudinal tumor and type-specific diagnosis of Borrmann type IV gastric cancer.

Materials and Methods

Fifty-nine patients (35 men with mean age of 60 years and 24 women with mean age of 55 years) who underwent surgical resection of Borrmann type IV gastric cancer were included in this study. Histopathological analysis data was used as a reference standard to confirm the clinical interpretations of gastroscopy and CT for the diagnosis of Borrmann type IV and evaluation of longitudinal tumor extent. For the evaluation of longitudinal extent, gastroscopic and CT results were classified as underestimated, accurate, or overestimated. The McNemar test was used to identify statistically significant differences in the accuracy between gastroscopy and CT.

Results

For the diagnosis of Borrmann type IV gastric cancer, the accuracy of CT was significantly higher than that of gastroscopy (74.6% [44/59] vs. 44.1% [26/59], p < 0.001). CT was significantly more accurate in assessing the overall tumor extent than gastroscopy (61.4% [35/57] vs. 28.1% [16/57], p < 0.001). The proximal (75.4% [43/57] vs. 50.9% [29/57], p = 0.003) and distal tumor extent (71.9% [41/57] vs. 43.9% [25/57], p < 0.05) were more accurately predicted by CT compared with gastroscopy. The underestimation of tumor extent was a major source of error in both examinations.

Conclusion

CT was found to be more predictive than gastroscopy in type-specific diagnosis and the evaluation of longitudinal tumor extent in patients with Borrmann type IV gastric cancer.

Abstract P3-12-05: Clinical features and outcomes of leptomeningeal metastasis in patients with breast cancer: a single center experience

Background: Leptomeningeal metastasis (LM) is one of the major problems in managing metastatic breast cancer because of LM typically carries a devastating prognosis and often represents a terminal event. We analyzed the clinical features and outcomes of LM in patients with breast cancer.

Methods: We retrospectively reviewed the medical records of patients who were diagnosed with LM from breast cancer between 2002 and 2012 at Asan Medical Center.

Results: Of the 95 LM patients by cytologically proven (n = 81) or radiologically diagnosed (n = 14), 57 (60%) had an ECOG performance status (PS) ≥ 3, and the median age was 47 years (range, 26–72 years). The patients were diagnosed with LM after a median of 10.3 months (95% CI, 5.5–15.0 months) from the time of diagnosis of metastatic breast cancer. LM was present in 2 patients at the time of initial diagnosis. Twenty-three patients (24.2%) had isolated CNS metastasis, and 6 (6.3%) had only LM without any detectable metastasis sites. At the time of diagnosis of LM, 46 patients (48.4%) presented with coincidental failure of systemic disease control. Seventy-eight patients (82.1%) underwent intrathecal chemotherapy (methotrexate; n=78, thiotepa; n=11), resulting in one-third of cytologic negative conversion (n = 26), and 41 (43.2%) received systemic chemotherapy. The overall median survival time was 3.3 months (95% CI, 2.5–4.2 months) and 7.8% of the patients survived for more than 1 year. Overall survival tended to be better in patients who achieved cytologic negative conversion to intrathecal chemotherapy than those did not (median 4.5 months versus 3.2 months, P = 0.241). Overall survival was not different according to subtypes; hormone receptor (+), HER2 (+), and triple negative (median 3.6 months, 3.3 months, and 3.2 months, P = 0.937). Multivariate analysis demonstrated that ECOG PS ≥ 3 (HR = 2.09, 95% CI 1.21–3.58, P = 0.007), coincidental failure of systemic disease control at LM (HR = 3.01, 95% CI 1.76–5.15, P &lt; 0.001), and systemic chemotherapy after LM (HR = 0.40, 95% CI 0.24–0.68, P = 0.001) were independent factors associated with survival.

Conclusions: The prognosis for patients with LM from breast cancer was still poor. Systemic chemotherapy in addition to intrathecal chemotherapy might confer a survival benefit, even after the detection of LM.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-12-05.

Abstract P3-01-02: Correlation of Mammographic breast density and tumor characteristics in Korean breast cancer patients

Introduction: Western studies have demonstrated high breast density as a strong risk factor for breast cancer, it is poorly understood whether breast density affects the diverse phenotypes of breast cancer. We examined the association between various tumor characteristics and mammographic breast density in women with breast cancer.

Methods: We conducted a cross-sectional analysis in 910 Korean women diagnosed with breast cancer to evaluate the associations between breast density and tumor size, lymph node status, lymphovascular invasion, histologic grade, estrogen receptor, progesterone receptor, HER2. Breast density was classified as fatty (percent density less than 50% by a computer-assisted thresholding program, named “Cumulus™”; n = 470) or dense (percent density 50% or more; n = 440) for the cancer-free breast at the time of operation. Logistic regression was used to examine whether the relationships were modified by adjustment for body mass index, age at diagnosis, age at first birth, menopausal status, history of breast-feeding, and breast cancer staging.

Results: Total 910 patients were involved, the mean age and median age at the operation was 48 years old (range 20–82), and the mean percent density was 48.09 (SD = 9.62 %: normally distributed, Kolmogorov-Smirnov test p = 0.32). Crude analysis shows that tumor size over than 0.5cm were more likely to have dense breasts compared with women with a tumor size &lt;=0.5 cm (OR = 3.21, 95% CI = 1.59–6.45, p = 0.001 for tumor sizes 0.6–1.0cm; OR = 2.02, 95% CI = 1.09–3.74, p = 0.03 for tumor sizes 1.1–1.5cm; OR = 1.8, 95% CI = 0.97–3.33, p = 0.06 for tumor sizes 1.6–2.0cm; and OR = 1.64, 95% CI = 0.92–2.94, p = 0.1 for tumor sizes 2.1cm or more). PD and histologic grade shows reverse association between histologic grade 1 and grade 2,3. Progesteron receptor positive patients tend to have more dense(OR = 1.27, 95% CI=0.97–1.66, p = 0.07) breast than receptor negative patients, although after adjustment of age the statistical significant disappeared. Percent density was not significantly associated with, ER (p = 0.74), HER2 (p = 0.72).

Development of a droplet-vitrification protocol for cryopreservation of Rubia akane (Nakai) hairy roots using a systematic approach

A systematic approach using a set of 13 treatments was applied to develop a droplet-vitrification protocol for Rubia akane hairy roots, based on their responses to preculture, loading, dehydration and cooling/rewarming steps. The roots were very sensitive to osmotic stress induced by both preculture in liquid sucrose-enriched medium (up to 0.5 M sucrose) and by dehydration with highly concentrated vitrification solutions (VSs). Loading was necessary before dehydration of explants with VS, and the composition of the loading solution (LS) significantly affected their post-cryopreservation regeneration. Due to high sensitivity of roots to both chemical cytotoxicity and osmotic stress produced by VSs, cryoprotection with alternative VSs, i.e. B5-80 percent (40 percent glycerol + 40 percent sucrose, w/v) at room temperature for 15 min or with A3-70 percent (29.2 percent glycerol + 11.7 percent DMSO + 11.7 percent EG + 17.4 percent sucrose, w/v) at 0 degree C for 20 min ensured the highest post-cryopreservation regeneration. However, when using these solutions, endothermic peaks (enthalpies) with -2.9 and -5.8 J per gram fresh weight, respectively, were recorded by differential scanning calorimetry (DSC) during the rewarming phase. Droplet-vitrification using foil strips showed higher post-cryopreservation regeneration (86 percent) compared with vitrification in cryovials (59 percent), possibly due to the higher cooling and rewarming rates achieved with droplet-vitrification. The developed protocol was applied to hairy roots of five other species with minor modifications in explant type, the duration of the last subculture before explant excision, and the dehydration duration with VS B5-80 percent.

Prevalence and clinicopathologic characteristics of gastric cardia cancer in South Korea

BACKGROUND AND AIM

Western reports have suggested that the prevalence of gastric cardia cancer (GCC) has been increasing, and indicated some differences between GCC and gastric noncardia cancer (GNCC). However, few studies have been conducted in Asia. The aims of this study were to estimate the prevalence of GCC and to evaluate differences of clinicopathologic characteristics between GCC and GNCC in South Korea.

METHODS

This study was single-center case-control study. A total of 829 patients with gastric cancer and 270 controls were enrolled between 2003 and 2011. Baseline characteristics, Helicobacter pylori (H. pylori) infection status, and histologic characteristics were compared among three groups (GCC, GNCC, and control).

RESULTS

Sixty cases (7.2%) of gastric cancer were located in cardia. Multivariate analysis showed that male odds ratio (OR, 5.72; 95% CI, 1.72-19.07; p = .005) and cigarette smoking (OR, 5.38; 95% CI, 1.39-20.90; p = .015) were risk factors of GCC in comparison with control group, but H. pylori infection rate was not significant. In the case of GNCC, cigarette smoking (OR, 3.87; 95% CI, 1.81-8.29; p < .001), past alcohol intake (OR, 2.82; 95% CI, 1.28-6.20; p = .010), intestinal metaplasia (OR, 3.22; 95% CI, 2.00-5.17; p < .001), and H. pylori infection (OR, 3.06; 95% CI, 1.90-4.93; p < .001) were risk factors of GNCC. Gastroesophageal reflux disease symptoms were higher in the GNCC (21.2%) than control group (13.5%) (p = .008). However, in the case of GCC, they were similar between the GCC (12.7%) and control group (p = .872). According to multivariate analysis, history of H. pylori eradication (OR, 0.34; 95% CI, 0.19-0.61; p < .001) was associated with a protective effect on GNCC. GCC showed higher depth of invasion (p = .038) and frequent distant metastasis (p = .012) than GNCC.

CONCLUSION

In this referral center based study, the prevalence of GCC was 7.2% in South Korea. Risk factors and clinicopathologic characteristics for GCC and GNCC were different, supporting that the pathophysiology is different in the development of GCC and GNCC.

Cryopreservation of Kalopanax septemlobus embryogenic callus using vitrification and droplet-vitrification

A cryopreservation protocol has been developed for embryogenic callus cultures of castor aralia (Kalopanax septemlobus), a deciduous tree which is widely used in oriental medicine and in landscape design. Three preculture treatments, four loading and six vitrification solutions were tested in a vitrification procedure. Preculture of embryogenic callus (EC) with high sucrose concentrations (up to 0.7 M) showed no effect on regrowth after cryopreservation. Loading for 20 min at ambient temperature improved regrowth of cryopreserved EC by 70-75 percent compared with non-loaded samples, regardless of the composition of the loading solution. Among vitrification solutions, the highest regrowth of 95-100 percent after cryopreservation was obtained after incubation of EC in a vitrification solution A3-80 percent comprising (w/v) 33.3 percent glycerol + 13.3 percent DMSO + 13.3 percent EG + 20.1 percent sucrose for 40 min at 0°C. Profiling of crystallization and recrystallization events using differential scanning calorimetry (DSC) confirmed that freezing injury was minimized in samples after loading and cryoprotection with this vitrification solution. Unlike many other papers, the droplet-vitrification protocol did not produce higher post-cryopreservation regrowth of Kalopanax EC, compared with the vitrification procedure. When samples are sufficiently cryoprotected during VS treatment, vitrification using cryovials may be preferred, since droplet-vitrification is more complex and requires skilled personnel. Cryopreserved callus grew rapidly and produced numerous somatic embryos, which developed similarly to embryos obtained from non-cryopreserved samples.

A new HLA-B*40:186 allele identified by sequence-based typing in a Korean individual

The new allele B*40:186 shows a one nucleotide substitution compared with B*40:01:02 at codon 56 (GGG → AGG) resulting in coding change, Gly to Arg.

Effect of endoscopic screening at 1-year intervals on the clinicopathologic characteristics and treatment of gastric cancer in South Korea

BACKGROUND AND AIM

The recommended interval of endoscopic screening for gastric cancer (GC) in a general population is 2 years in Korea. However, it has not been determined whether endoscopic screening with a shorter interval is beneficial, especially for high-risk groups.

METHODS

A total of 415 patients with GC were categorized according to whether they had (vigilant screening group) or not (non-vigilant screening group) undergone endoscopic screening within 1 year before being diagnosed with GC. Clinicopathologic GC characteristics of the two groups were compared. Next, the same analyses were conducted in subgroups of patients with high risk for GC including males, current smokers, first-degree relatives of GC; and patients with Helicobacter pylori infection, gastric atrophy, or intestinal metaplasia (IM).

RESULTS

The proportion of vigilant screening patients was 36.1%. Early gastric cancer (EGC) was more frequently observed in the vigilant screening group than the non-vigilant screening group (62.7% vs 49.4%, P = 0.009). In the high-risk factor analyses, EGC was more frequently detected among patients with severe IM in the vigilant screening group than the non-vigilant screening group (66.7% vs 35.5%, P = 0.047). In addition, more patients in the vigilant screening group had undergone endoscopic submucosal dissection (ESD; 26.7% vs 0%, P = 0.008) and had stage I (84.6% vs 41.7%, P = 0.012) than in the non-vigilant screening group.

CONCLUSIONS

Endoscopic screening for GC at 1-year intervals would be beneficial for patients with severe IM in South Korea; this method could detect EGC for which the curative modality would be ESD.

Abstract 1701: Clinical significance of serum and tissue Dickkopf-1 in patients with gastric cancer

Background: Dickkopf-1 (DKK-1) is a secreted protein known as a negative regulator of the Wnt signaling pathway and involved in embryonic development and tumorigenesis. Clinical significance of serum DKK-1 and tissue DKK-1 expression in gastric cancer has not been clarified. Methods: Serum concentrations of DKK-1 were assessed by enzyme-linked immunosorbent assay in 153 gastric cancer patients and 33 healthy controls. We also obtained serum CEA (ng/mL) and CA19-9 (U/mL) values by chemiluminescence immunoassay. For tissue DKK-1, we performed immunohistochemical staining for DKK-1 in 144 cancer specimens of 153 patients and in additional 265 consecutive gastric cancer specimens. Results: Serum DKK-1 concentrations were significantly higher in gastric cancer patients (56.27 pg/mL) than in healthy controls (30.50 pg/mL, p=0.018). With 36.3150 pg/mL of cut-off value, sensitivity and specificity for gastric cancer diagnosis were 80.4% and 78.8%, respectively. Gastric cancer patients with a serum DKK-1 of 60.0 pg/mL or higher had a significantly diminished survival compared with patients whose serum DKK-1 were lower (p=0.033). By immunohistochemistry, DKK-1 overexpression in cancer specimens was significantly correlated with increased serum DKK-1 concentrations (correlation coefficient, 0.395; p&lt;0.001). The cancer patients with DKK-1 overexpression had a significantly worse prognosis than the patients without DKK-1 expression in this cohort (p=0.004) and additional consecutive cases (p=0.030). By multivariate Cox regression model, DKK-1 expression status predicted patient prognosis independently of pTNM stage and histologic differentiation in consecutive cases (p=0.018). Conclusion: Increased serum DKK-1 concentrations and overexpression of DKK-1 in gastric cancer tissue may contribute to diagnosing gastric cancer and predicting cancer patient outcome.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1701. doi:1538-7445.AM2012-1701

Long-term outcomes and feasibility with laparoscopy-assisted gastrectomy for gastric cancer

Purpose

Recently, laparoscopy-assisted gastrectomy (LAG) has been widely accepted modality for early gastric cancer in Korea. The indication of LAG may be extended in an experienced institution. In our institution, the first case of laparoscopy-assisted gastrectomy (LAG) for gastric cancer was performed in May 1998. We retrospectively reviewed the long-term oncologic outcomes over 12 years to clarify the feasibility of LAG for gastric cancer.

Materials and Methods

The authors retrospectively analyzed 753 patients who underwent LAG for gastric cancer, from May 1998 to August 2010. We reviewed clinicopathological features, postoperative outcomes, mortality and morbidity, recurrence, and survival of LAG for gastric cancer.

Results

During the time period, 3,039 operations for gastric cancer were performed. Among them, 753 cases were done by LAG (24.8%). There were 69 cases of total gastrectomy, 682 subtotal gastrectomies, and 2 proximal gastrectomies. According to TNM stage, 8 patients were in stage 0, 619 in stage I, 88 in stage II, and 38 in stage III. The operation-related complications occurred in 77 cases (10.2%). Median follow-up period was 56.2 months (range 0.7~165.6 months). Twenty-five patients (3.3%) developed recurrence, during the follow-up period. The overall 5-year and disease free survival rates were 97.1% and 96.3%, respectively.

Conclusions

The number of postoperative complications and survival rates of our series were comparable to the results from that of other reports. The authors consider LAG to be a feasible alternative for the treatment of early gastric cancer. However, rationale for laparoscopic surgery in advanced gastric cancer has yet to be determined.