[Collision Tumor Involving Primary Ascending Colon Cancer and Malignant Lymphoma].

A 78-year-old male was diagnosed with a primary gastric B-cell malignant lymphoma and metastatic lung tumor 10 years ago. He underwent chemotherapy at another hospital, achieved complete remission, and was actively undergoing follow- up. He presented to our hospital with a 1-month history of a bulge in his right lower abdomen. CT revealed thickening of the ascending colon and dilatation of the oral intestine. He was diagnosed with ascending colon cancer and underwent right hemicolectomy. The subsequent pathological examination revealed a collision tumor involving diffuse, large B-cell lymphoma and well-differentiated adenocarcinoma. He was discharged from our hospital and received chemotherapy at another institution. Unfortunately, the patient died of interstitial pneumonia 31 months postoperatively. This report describes the resection of a collision tumor involving ascending colon cancer and malignant lymphoma. Surgical treatment combined with postoperative chemotherapy improved this patient's long-term survival.

[Malignant Melanoma of a Male Breast That Was Difficult to Differentiate from Breast Cancer-A Case Report].

INTRODUCTION: Malignant melanoma in the male breast is extremely rare. Here we report a case of malignant melanoma in which a small cystic lesion in the male breast gradually increased during follow-up and was difficult to distinguish from breast cancer. CASE: A 65-year-old male was diagnosed with a tumor in the right breast and was referred to our department for further examination. At 42 years of age, he underwent tumor resection of a malignant melanoma of the abdominal skin. Mammary ultrasonography showed a 0.6 cm cystic mass in his right breast. Eight months later, the right breast mass had increased to 1.4 cm, and a core needle biopsy suggested breast cancer. Total mastectomy with axillary lymph node dissection was performed. HE staining of the resected tumor showed intranuclear inclusion bodies and some large nucleoli. On the basis of various immunostaining methods, malignant melanoma was diagnosed instead of breast cancer. After surgery, adjuvant chemotherapy with molecularly targeted drugs was administered. DISCUSSION: This might have been a case of male breast metastasis of malignant melanoma with very late recurrence.

[Laparoscopic Tumor Resection for Asymptomatic Paraganglioma-A Case Study].

A 55-year-old man was referred for the close examination of an abdominal mass noted on abdominal ultrasonography during a physical examination. A contrast-enhanced computed tomography(CT)scan of his abdomen revealed a 36-mm heterogeneously contrast-enhanced mass on the left side of the aorta. He was referred for laparoscopic tumor resection without preoperative histological examination. The tumor was identified from the dorsal aspect of the mesentery of the transverse colon and was resected only because it was detachable from the duodenum. A temporary abnormal hypertension was observed intraoperatively. However, he exhibited a favorable postoperative course and was discharged on the 8th postoperative day. Grossly, it was a nodular tumor with a diameter of 38 mm. Histopathological examination revealed that the tumor cells having abundant cytoplasm formed large foci and were surrounded by sinusoidal vessels. Immunohistochemistry results were positive for chromogranin A, synaptophysin, and neural cell adhesion molecule; thus, paraganglioma was diagnosed. Herein, we report a case of laparoscopic resection of an asymptomatic paraganglioma.

Laparoscopic versus open distal gastrectomy for early gastric cancer in Japan: long-term clinical outcomes of a randomized clinical trial.

PURPOSE: We report the long-term clinical outcomes of a randomized clinical trial comparing laparoscopy-assisted distal gastrectomy (LADG) with open DG (ODG). METHODS: Between 2005 and 2008, 63 patients with clinical T1 (cT1) gastric cancer were randomly assigned to undergo either LADG or ODG. Long-term clinical outcomes included prospective questionnaire-based symptoms and survival. RESULTS: Based on the responses to the prospective questionnaires, patients who underwent LADG reported greater satisfaction and were more likely to favor the procedure than those who underwent ODG. The most notable difference in symptoms was related to wound pain and diarrhea. After ODG, wound pain reduced in intensity but persisted throughout the follow-up. Surprisingly, diarrhea was more frequent after LADG than after ODG, possibly due to overeating, because symptoms elicited by overeating, such as vomiting after a meal or heartburn, were also more frequent after LADG. In terms of long-term survival, there were no cases of recurrence in either group. CONCLUSIONS: LADG was associated with less wound pain during long-term follow-up after surgery, whereas symptoms related to overeating were common. Based on our findings and the patients' reported satisfaction, we recommend LADG for cT1 gastric cancer as an effective procedure with excellent long-term survival.

Laparoscopy versus open distal gastrectomy by expert surgeons for early gastric cancer in Japanese patients: short-term clinical outcomes of a randomized clinical trial.

BACKGROUND: Short-term outcomes of laparoscopy-assisted distal gastrectomy (LADG) and open DG (ODG) have been investigated in previous clinical trials, but operative techniques and concomitant treatments have evolved, and up-to-date evidence produced by expert surgeons is required to provide an accurate image of the relative efficacies of the treatments. The purpose of this study was to compare laparoscopic versus ODG with respect to specific primary and secondary short-term outcomes. METHODS: From October 2005 to February 2008, a total of 64 patients with early gastric cancer were randomly assigned to the LADG or the ODG group. One patient was excluded due to concurrent illness unrelated to the intervention, so the data from 63 patients were analyzed. The primary short-term outcome was the 4-day postoperative use of analgesics. Secondary short-term outcomes were postoperative residual pain, complications, days hospitalized, blood data, days with fever, and days to first flatus. RESULTS: There was a significant difference in favor of LADG for postoperative use of analgesics (P = 0.022). Unexpectedly, there was no significant difference in degree of pain in the immediate postoperative period, putatively due to the optimal use of analgesics. Of the secondary outcomes, residual pain at postoperative day 7 (P = 0.003) and days to first flatus (P = 0.001) were significantly better with LADG. Postoperative complications, number of days hospitalized, and number of days with fever were also better with LADG, but the differences were not significant. Blood data representing inflammation (WBC and CRP) showed marked differences, especially on postoperative day 7 (P = 0.0016 and P = 0.0061, respectively). CONCLUSIONS: LADG performed by expert surgeons results in less postoperative pain accompanied by decreased surgical invasiveness and is associated with fewer postoperative inconveniences. No preliminary suggestions of changes in long-term curability were observed. LADG for early gastric cancer is a feasible and safe procedure with short-term clinical results superior to those of ODG.

Effect of Four Main Gastrectomy Procedures for Proximal Gastric Cancer on Patient Quality of Life: A Nationwide Multi-Institutional Study.

PURPOSE: This study aimed to examine the effects of 4 main types of gastrectomy for proximal gastric cancer on postoperative symptoms, living status, and quality of life (QOL) using the Postgastrectomy Syndrome Assessment Scale-45 (PGSAS-45). MATERIALS AND METHODS: We surveyed 1,685 patients with upper one-third gastric cancer who underwent total gastrectomy (TG; n=1,020), proximal gastrectomy (PG; n=518), TG with jejunal pouch reconstruction (TGJP; n=93), or small remnant distal gastrectomy (SRDG; n=54). The 19 main outcome measures (MOMs) of the PGSAS-45 were compared using the analysis of means (ANOM), and the general QOL score was calculated for each gastrectomy type. RESULTS: Patients who underwent TG experienced the lowest postoperative QOL. ANOM showed that 10 MOMs were worse in patients with TG. Four MOMs improved in patients with PG, while 1 worsened. One MOM was improved in patients with TGJP versus 8 MOMs in patients with SRDG. The general QOL scores were as follows: SRDG (+39 points), TGJP (+6 points), PG (+3 points), and TG (-1 point). CONCLUSIONS: The TG group experienced the greatest decline in postoperative QOL. SRDG and PG, which preserve part of the stomach without compromising curability, and TGJP, which is used when TG is required, enhance the postoperative QOL of patients with proximal gastric cancer. When selecting the optimal gastrectomy method, it is essential to understand the characteristics of each and actively incorporate guidance to improve postoperative QOL.

Detection of Kita-Kyushu Lung Cancer Antigen-1, a Cancer/Testis Antigen, in the Stomach Close to a Cancerous Condition.

Background: Kita-Kyushu lung cancer antigen-1 (KK-LC-1), encoded by CT83, is a cancer/testis antigen (CTA) and an attractive target for immunotherapy. Our previous study demonstrated frequent CT83 expression in gastric cancers (GCs) and non-tumor sites of the stomach with tumors. Additionally, there was a correlation with Helicobacter pylori (Hp) infection. Since it currently remains unclear whether KK-LC-1 is expressed in the stomach without GC, this study investigated KK-LC-1 expression in non-GC stomach. Methods: We investigated differences in CT83 gene expression at non-tumor sites of stomachs with or without tumors in 118 GC patients and 115 non-GC patients. Fisher's exact test was used for statistical analyses. Results: CT83 expression was detected in 77% of non-tumor sites in stomachs with tumors, which was significantly higher than in stomachs without tumors (7%, p < 0.0001). All patients with CT83 expression at non-tumor sites of their stomachs without tumors carried Hp. Conclusion: CT83 appears to be rarely expressed in the atrophic stomach, and furthermore, a part of patients positive for its expression will develop GC in the future, suggesting that CT83 expression is a useful marker for predicting GC.

Taxane-based versus platinum-based chemotherapy in early recurrent gastric cancer after radical surgery with S-1 adjuvant chemotherapy: A multi-institutional retrospective analysis.

AIM: This study aimed to compare the efficacy of taxane-based and platinum-based regimens in patients with early recurrent gastric cancer after radical surgery with S-1 adjuvant chemotherapy. METHODS: The medical records of 118 patients from six institutes with early recurrent stage II/III gastric cancer, who developed recurrence during adjuvant S-1 or within 6 months after completion of adjuvant therapy between January 2006 and December 2017, were retrospectively analyzed. Patients treated with second line chemotherapy were enrolled and followed to the end of December 2019. The impact of two regimens, taxane-based (n = 46) versus platinum-based (n = 31), on treatment outcome were evaluated using multivariate analysis. RESULTS: Median overall survival was 9.0 months and median progression-free survival was 4.1 months. No difference was observed in overall survival between taxane-based and platinum-based regimens (P = 0.64). Although not significant, the response rate of platinum-based regimens was better than that of taxane-based regimens (16% vs. 6.5%, P = 0.26). Multivariate analysis identified performance status (P = 0.040), multiorgan metastases (P = 0.029), and undifferentiated histological type (P = 0.018) as independent poor prognostic factors. In undifferentiated histological type, multiorgan metastases (P = 0.013) and taxane-based regimens (P = 0.018) were independent prognosis factors characterized by multivariate analysis. Conversion rate to third-line chemotherapy or more was 51% in undifferentiated histological type and 65% in differentiated histological type (P = 0.26). CONCLUSION: Platinum-based regimens may be recommended for undifferentiated early recurrent gastric cancer after S-1 adjuvant chemotherapy.

Lymphatic tumor emboli detected by D2-40 immunostaining can more accurately predict lymph-node metastasis.

BACKGROUND: Resected specimens of superficial squamous cell carcinoma of the esophagus (SSCCE) underwent D2-40 immunostaining to accurately assess lymphatic tumor emboli (LY) and to analyze correlations between LY and lymph node metastasis (N). This present study was designed to determine the accuracy of LY grade for predicting the risk of N. MATERIALS AND METHODS: We studied 75 patients with SSCCE who underwent surgical resection of their tumors. Resected specimens were sliced into continuous sections at 5 mm intervals. Intramucosal cancers are classified into three groups (m1, m2, m3), and submucosal cancers are also divided into three groups (sm1, sm2, sm3). The numbers of LY present in lymphatic ducts on D2-40 immunostaining, venous tumor emboli (V) on CD34 immunostaining, and lymphatic tumor emboli (ly) and V on hematoxylin-eosin staining (HE) and elastica van Gieson staining (EVG) were counted for each case. The presence of lymphatic tumor emboli was graded according to the total number of LY per case as follows: 0, LY0; 1 to 2, LY1; 3 to 9, LY2; and 10 or more, LY3. RESULTS: All m1 and m2 cases were LY- and N- Lymphatic tumor emboli were present in 54% of m3 cases, 70% of sm1 cases, 54% of sm2 cases, and 75% of sm3 cases. Determination of N was positive in 18% of m3 cases, 47% of sm1 cases, 36% of sm2 cases, and 62% of sm3 cases. The frequency of LY significantly correlated with the number of N (p < 0.0001). Multiple regression analysis showed that only LY and V significantly correlated with N. When the detection rate of N was compared between LY and ly, LY was superior to ly in terms of specificity, accuracy, positive predictive value, and false positive rate. As for LY grade, N was positive in 39.1% of LY1 cases, 81.8% of LY2 cases, and 100% of LY3 cases. Even in LY-, N was positive in one sm1 case and in two sm2 cases. In the sm1 case, the depth of invasion was 350 µm from the lower margin of the muscularis mucosae. CONCLUSIONS: Evaluation of lymphatic invasion on the basis of LY is more accurate for the prediction of N than conventional techniques, and LY grade strongly correlates with N. In patients with SSCCE, mucosal cancers (m1, m2, and m3) and submucosal cancers with a depth of invasion of ≤ 200 µm from the lower margin of the muscularis mucosae on endoscopic mucosal resection have a low risk of N if the number of LY is 0. Endoscopic mucosal resection alone can provide good treatment outcomes in such patients.

[A case of squamous cell cancer of the breast in which effective hemostasis was obtained by preoperative emergency radiation].

A case was a 40-year-old woman. Her right breast was presented with massive bleeding ulcer and fixed with a pectoral muscle. Diagnosis of Stage IIIb breast cancer( T4b, N1, M0) showed a high inflammatory response and severe anemia. Palliative surgery was difficult because of hemostasis, and her general health also was in poor condition. The pathological diagnosis was squamous cell cancer. We underwent a total of 30 Gy radiation emergency hemostasisose. After radiation and chemotherapy, the lesion was undergone a radical surgery, and was reduced in size significantly. It was diagnosed as squamous cell cancer, which was more sensitive to general radiation so neoadjuvant chemoradiation therapy was effective.

Prognosis of hemodialysis patients undergoing surgery for gastric cancer: Results of a multicenter retrospective study.

BACKGROUND: Little is known about the survival outcomes of and predictive factors for survival in hemodialysis patients undergoing surgery for gastric cancer. METHODS: We performed a multicenter retrospective study from 9 institutions to investigate the survival outcomes of 75 hemodialysis patients with gastric cancer. Patient characteristics included demographic data, hemodialysis- and gastric cancer-related variables. Multivariate Cox hazards models were applied to determine independent predictors of poor overall survival and non-gastric cancer related death. RESULTS: Stage I disease was predominant (58.7%) in our series. The overall morbidity and the 30-day mortality rates were 25.3% and 1.3%, respectively. The 5-year overall survival rates of patients with pStages I, II, III, and IV disease were 59.2%, 42.9%, 32.3%, and 0%, respectively. Eleven (14.7%) patients died of gastric cancer, whereas many more (40.0%) died owing to causes other than gastric cancer. Non-gastric cancer-related death was especially prevalent in patients with pStages I (95.2%) and II (75.0%) disease. Multivariable analysis revealed advanced age, long duration of hemodialysis (> 5 years), total gastrectomy, and pStage IV disease to be independently associated with poor overall survival. Notably, advanced age, long duration of hemodialysis, and the presence of cardiovascular disease were all independent predictors of non-gastric cancer-related death. Patients with all 3 factors had very poor survival outcomes (3-year overall survival; 14.3%). CONCLUSION: The survival outcomes of hemodialysis patients with gastric cancer, especially those with early-stage gastric cancer, were clearly poor, largely owing to the increased risk of non-gastric cancer-related death. Preoperative comorbidities and hemodialytic features were useful for predicting long-term outcomes of this vulnerable population.

Laparoscopy-assisted distal gastrectomy for early gastric cancer with complete situs inversus: report of a case.

We herein report our experience in performing a laparoscopy-assisted distal gastrectomy involving standard lymph node dissection for a patient with early gastric cancer and situs inversus. A superficial elevated lesion was found on the posterior wall of the antrum. The preoperative diagnosis was cStage IA (cT1, cN0, cH0, cP0, cM0). A laparoscopy-assisted distal gastrectomy with standard lymph node dissection (D1 + beta) for early gastric cancer was successfully performed by shifting the monitor to the right and left, and by applying sufficient care and time. The course of blood vessels was not abnormal except for the right/left inversion. Billroth I reconstruction was performed through a delta-shaped anastomosis. The postoperative course was favorable and the patient was discharged on postoperative day 12. Based on a histopathological examination, a 5.0 x 5.0-cm, mucosal, poorly differentiated adenocarcinoma (pT1, pN0, sH0, sP0, sM0, Stage IA) was diagnosed.

Cancer/testis antigen, Kita-Kyushu lung cancer antigen-1 and ABCD stratification for diagnosing gastric cancers.

BACKGROUND: The ABCD stratification [(combination of serum pepsinogen (PG) levels and titers of antibody (immunoglobulin G, IgG) against Helicobacter pylori (H. pylori)] is effective for the classification of individuals at risk of developing gastric cancer (GC). The Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a Cancer/Testis antigen frequently expressed in GC. AIM: To evaluate the effectiveness of KK-LC-1 and ABCD stratification in the diagnosis of GC. METHODS: We analyzed the gene expression of KK-LC-1 in surgical specimens obtained from GC tumors. The levels of serum PG I/PG II and IgG against H. pylori were measured. According to their serological status, the patients were classified into the four groups of the ABCD stratification. RESULTS: Of the 77 examined patients, 63 (81.8%) expressed KK-LC-1. The IgG titers of H. pylori and PG II were significantly higher in patients expressing KK-LC-1 than those measured in patients not expressing KK-LC-1 (P = 0.0289 and P = 0.0041, respectively). The expression of KK-LC-1 in group C [PG method (+)/H. pylori infection (+)] was as high as 93.9% high. KK-LC-1 was also detected in group A [-/-]. CONCLUSION: The KK-LC-1 expression in GC was associated with H. pylori infection and atrophic status, so that, KK-LC-1 may be a useful marker for the diagnosis of GC.

Laparoscopy-assisted pancreas- and spleen-preserving total gastrectomy for gastric cancer as compared with open total gastrectomy.

BACKGROUND: Laparoscopy-assisted total gastrectomy (LATG) is not widely used for the treatment of gastric cancer located in the upper or middle third of the stomach. To assess the safety and usefulness of LATG, we compared the outcomes of LATG with those of open total gastrectomy (OTG). METHODS: From July 2004 to July 2007, we performed pancreas- and spleen-preserving total gastrectomy with D1 + beta or D2 lymph-node dissection and Roux-en-Y reconstruction in 74 patients with cancer located in the upper or middle third of the stomach. Of these patients, 30 underwent LATG (LATG group) and 44 underwent OTG (OTG group). Short-term outcomes were compared between the groups. RESULTS: Operation time was significantly longer in the LATG group than in the OTG group (313 min vs. 218 min, p < 0.001). Blood loss (134 g vs. 407 g, p < 0.001) and the rate of the use of analgesics (6.8 times vs. 11.8 times, p < 0.05) were significantly lower, and postoperative hospital stay was significantly shorter in the LATG group than in the OTG group (13.5 days vs. 18.2 days, p < 0.05). The LATG group had better hematologic and serum chemical profiles, including white-cell counts, C-reactive protein levels, total protein levels, and albumin levels, as well as lower rate of postoperative body-weight loss. The number of dissected lymph nodes (43.2 vs. 51.2, p = 0.098) and the rate of postoperative complications (20.0% vs. 27.3%, p = 0.287) were similar in the groups. However, major complications such as anastomotic leakage, abdominal abscess, and pancreatic leakage occurred in six patients (13.6%) in the OTG group, but in none of the patients in the LATG group. CONCLUSIONS: LATG is associated with less severe complications and better postoperative quality of life than OTG. We believe that LATG is a safe, useful, and less invasive alternative for the treatment of gastric cancer located in the upper or middle third of the stomach.

Expression of Kita-Kyushu Lung Cancer Antigen-1 as Detected by a Novel Monoclonal Antibody in Gastric Cancer.

BACKGROUND/AIM: Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a known cancer/testis antigen. Our group has previously shown KK-LC-1 gene expression in gastric cancer. However, could not be detected the KK-LC-1 protein due to the lack of an appropriate antibody. Here, we assessed our original monoclonal antibody (Kmab34B3) and, using it, assessed the expression of KK-LC-1 in gastric cancer. PATIENTS AND METHODS: We evaluated an original monoclonal antibody against KK-LC-1 (Kmab34B3), and used this antibody to compare KK-LC-1 protein expression in tumour and non-tumour stomach cells from gastric cancer patients. RESULTS: Kmab34B3 stained testicular germ cells, and tumour cells in nine out of 11 (82%) specimens. In non-tumorous areas, Kmab34B3 stained 13 out of 29 (45%) pyloric gland specimens. Furthermore, Kmab34B3 also stained intestinal metaplasia positive and negative areas. CONCLUSION: Kmab34B3 was able to detect KK-LC-1 protein within tumour cells and the pyloric gland where the gene has been shown to be expressed. Therefore, it might be an attractive tool for detecting KK-LC-1 expression in precancerous and cancerous stomach cells.

A new diagnostic method for early gastric cancer: volume measurement by 3-dimensional endoscopic ultrasonography in early gastric cancer and its clinical significance.

BACKGROUND: The objective of the present study was to measure the volume of early gastric cancer using 3-dimensional endoscopic ultrasonography (3D-EUS) and to ascertain the clinical significance of this new diagnostic method. PATIENTS AND METHODS: The study comprised 100 patients with early gastric cancer who underwent preoperative 3D-EUS followed by surgical resection. The relationships of lymph node metastasis to 10 clinicopathological factors (gender, age, tumor location, ulcer, depth, macroscopic type, tumor histology, lymphatic invasion and venous invasion) and preoperative tumor volume (log tumor volume) as measured by 3D-EUS were determined. RESULTS: Median tumor volume was 414.75 mm3 (range, 7.8-2,683.8 mm3) and median log tumor volume was 2.617 (range, 1.444-3.429). Univariate analyses showed that three factors (lymphatic invasion, p=0.0001; venous invasion, p=0.0216; log tumor volume, p=0.0121) correlated significantly with lymph node metastasis. Multivariate analysis showed only two factors (lymphatic invasion, p=0.011, regression coefficient=0.104; log tumor volume, p=0.020, regression coefficient=30.414) representing independent predictors for lymph node metastasis. CONCLUSION: Tumor volume as measured by 3D-EUS represents an independent risk factor for lymph node metastasis in early gastric cancer. This new method can be used as a reliable diagnostic tool for early gastric cancer.

Detection of KK-LC-1 Protein, a Cancer/Testis Antigen, in Patients with Breast Cancer.

BACKGROUND: Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen and predominant target for cancer immunotherapy. Its detection is only established based on gene expression. In this study, we established a monoclonal antibody against KK-LC-1 to detect its protein expression in formalin-fixed samples. MATERIALS AND METHODS: The monoclonal antibody against KK-LC-1 was evaluated and the detection of KK-LC-1 between gene expression and protein expression was compared in patients with breast cancer. The monoclonal antibody clone 34B3, which we established, stained testicular germ cells positively. RESULTS: The rates of detection of KK-LC-1 gene and protein expression were 11.8% and 52.9%, respectively. Protein expression was detected in all triple-negative breast cancer cases studied (n=8). Furthermore, KK-LC-1 was detected in all tumours without oestrogen receptor expression. CONCLUSION: This study indicated that KK-LC-1 expression was detected in breast cancer, especially in oestrogen receptor-negative subtypes.

Expression of KK-LC-1, a cancer/testis antigen, at non-tumour sites of the stomach carrying a tumour.

Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen (CTA) and predominant target for cancer immunotherapy. Our previous study indicated that KK-LC-1 was expressed in 82% of gastric cancers, and also in 79% of early stage of gastric cancers, with a correlation to Helicobacter pylori (H. pylori) infection. In addition, we found that KK-LC-1 was occasionally expressed at non-tumour sites of stomachs carrying tumours. Here, we investigated the characteristics of KK-LC-1 expression at non-tumour sites and the clinical utility of these phenomena. The gene expression of KK-LC-1 was detected at the non-tumour sites including pyloric glands. The most detectable corpus/gland subset had a KK-LC-1 expression rate of 77% in the pyloric gland of the lower corpus where H. pylori preferentially exists. KK-LC-1 expression rates were 67% or 32% with or without intestinal metaplasia, which also induced by H. pylori, respectively. Consequently, KK-LC-1 would be detected at the pre-cancerous condition of the stomach, and may be a useful marker to predict gastric cancer.

Correlation Between Expression of the Cancer/Testis Antigen KK-LC-1 and Helicobacter pylori Infection in Gastric Cancer.

BACKGROUND/AIM: Our previous study indicated that Kita-kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen (CTA) expressed in 82% of gastric cancer cases. Here, we investigated the relationship between KK-LC-1 expression and Helicobacter pylori infection in Japanese patients with gastric cancer. PATIENTS AND METHODS: We examined CTA expression in 25 surgical gastric cancer specimens and anti-H. pylori IgGs in the serum of each patient. RESULTS: KK-LC-1 was expressed in 80% of tumor samples, markedly higher than melanoma antigen gene (MAGE)-A1, MAGE-A3, MAGE-A4, synovial sarcoma, X breakpoint 4 (SSX4) and New York esophageal squamous cell carcinoma-1 (NY-ESO-1). Anti-H. pylori IgG titers from the KK-LC-1-positive patients were significantly higher (67.5±7.6) than those from KK-LC-1-negative patients (15.8±7.5, p<0.01) although there were no significant differences between patients positive and negative for MAGE-A1, -A3 and-A4, SSX4 and NY-ESO-1. CONCLUSION: As far as we are aware, this is the first report of a correlation between a carcinogen and CTA expression in clinical samples. KK-LC-1 was frequently expressed in gastric cancer caused by H. pylori infection. The risk diagnosis for gastric cancer might be more accurate if KK-LC-1 expression status were also considered.

Early gastric cancer frequently has high expression of KK-LC-1, a cancer-testis antigen.

AIM: To assess cancer-testis antigens (CTAs) expression in gastric cancer patients and examined their associations with clinicopathological factors. METHODS: Eighty-three gastric cancer patients were evaluated in this study. Gastric cancer specimens were evaluated for the gene expression of CTAs, Kitakyushu lung cancer antigen-1 (KK-LC-1), melanoma antigen (MAGE)-A1, MAGE-A3 and New York esophageal cancer-1 (NY-ESO-1), by reverse transcription PCR. Clinicopathological background information, such as gender, age, tumor size, macroscopic type, tumor histology, depth of invasion, lymph node metastasis, lymphatic invasion, venous invasion, and pathological stage, was obtained. Statistical comparisons between the expression of each CTA and each clinicopathological background were performed using the χ2 test. RESULTS: The expression rates of KK-LC-1, MAGE-A1, MAGE-A3, and NY-ESO-1 were 79.5%, 32.5%, 39.8%, and 15.7%, respectively. In early stage gastric cancer specimens, the expression of KK-LC-1 was 79.4%, which is comparable to the 79.6% observed in advanced stage specimens. The expression of KK-LC-1 was not significantly associated with clinicopathological factors, while there were considerable differences in the expression rates of MAGE-A1 and MAGE-A3 with vs without lymphatic invasion (MAGE-A1, 39.3% vs 13.6%, P = 0.034; MAGE-A3, 47.5% vs 18.2%, P = 0.022) and/or vascular invasion (MAGE-A1, 41.5% vs 16.7%, P = 0.028; MAGE-A3, 49.1% vs 23.3%, P = 0.035) and, particularly, MAGE-A3, in patients with early vs advanced stage (36.5% vs 49.0%, P = 0.044), respectively. Patients expressing MAGE-A3 and NY-ESO-1 were older than those not expressing MAGE-A3 and NY-ESO-1 (MAGE-A3, 73.7 ± 7.1 vs 67.4 ± 12.3, P = 0.009; NY-ESO-1, 75.5 ± 7.2 vs 68.8 ± 11.2, P = 0.042). CONCLUSION: The KK-LC-1 expression rate was high even in patients with stage I cancer, suggesting that KK-LC-1 is a useful biomarker for early diagnosis of gastric cancer.