Risk of second malignancies in patients with gastric marginal zone lymphomas of mucosa associate lymphoid tissue (MALT).

BACKGROUND: It is controversial whether patients with gastric marginal zone lymphomas of mucosa associated lymphoid tissue (MALT) have higher risk of second malignancies. The aim of this study was to define the risk of second malignancies in these patients. METHODS: We analyzed prospective follow-up data of 146 consecutive patients with gastric MALT lymphoma treated at Aichi Cancer Center Hospital and compared the incidence of second malignancies with that in the general population. We calculated the standardized incidence ratio (SIR), using age- and sex-specific incidence rates from the Aichi Cancer Registry. RESULTS: The median follow-up period was 74 months. A total of 27 tumors occurred in 22 patients (15.1%), including 19 solid tumors. Of these, nine tumors were detected concomitantly with, and 18 tumors following, the diagnosis of gastric MALT lymphoma. Four patients had two second malignancies each. For the entire group, the SIR of an additional malignancy was 3.39 (95% confidence interval [CI] 2.11-4.66). An increased incidence of solid tumors (SIR 2.91 [1.60-4.22]) and hematologic malignancies (SIR 5.54 [1.70-9.38]) were seen. In addition, there was increased risk for development of second malignancies during follow up (SIR 2.26 [1.21-3.30]). Chemotherapy for treatment of MALT was an independent risk factor for second malignancies (age-sex adjusted hazard ratio 3.98 [1.47-10.79]. CONCLUSIONS: Compared with the general population, patients with gastric MALT lymphoma are at increased risk for second malignancies, including gastric cancer.

A functional single nucleotide polymorphism in mucin 1, at chromosome 1q22, determines susceptibility to diffuse-type gastric cancer.

BACKGROUND & AIMS: Two major types of gastric cancer, intestinal and diffuse, develop through distinct mechanisms; the diffuse type is considered to be more influenced by genetic factors, although the mechanism is unknown. Our previous genome-wide association study associated 3 single nucleotide polymorphisms (SNPs) with diffuse-type gastric cancer (DGC); 1 was a functional SNP (rs2294008) in prostate stem cell antigen (PSCA), but the loci of the other 2 were not investigated. METHODS: We performed high-density mapping to explore a linkage disequilibrium status of the 2 SNPs at chromosome 1q22. A DGC case-control study was conducted using DNA from 606 cases and 1264 controls (all Japanese individuals) and validated using DNA from Japanese (304 cases, 1465 controls) and Korean (452 cases, 372 controls) individuals. The effects of SNPs on function were analyzed by reporter assays and analyses of splice variants. RESULTS: A region of a strong linkage disequilibrium with the 2 SNPs contained mucin 1 (MUC1) and other 4 genes and SNPs significantly associated with DGC (rs2070803: P = 4.33 × 10(-13); odds ratio [OR], 1.71 by meta-analysis of the studies on the 3 panels) but not with intestinal-type gastric cancer. Functional studies demonstrated that rs4072037 (P = 1.43 × 10(-11); OR, 1.66 by meta-analysis) in MUC1 affects promoter activity and determines the major splicing variants of MUC1 in the gastric epithelium. Individuals that carry both SNPs rs2294008 in PSCA and rs4072037 in MUC1 have a high risk for developing DGC (OR, 8.38). CONCLUSIONS: MUC1 is the second major DGC susceptibility gene identified. The SNPs rs2070803 and rs4072037 in MUC1 might be used to identify individuals at risk for this type of gastric cancer.

Characteristic methylation profile in CpG island methylator phenotype-negative distal colorectal cancers.

Aberrant DNA methylation is involved in colon carcinogenesis. Although the CpG island methylator phenotype (CIMP) is defined as a subset of colorectal cancers (CRCs) with remarkably high levels of DNA methylation, it is not known whether epigenetic processes are also involved in CIMP-negative tumors. We analyzed the DNA methylation profiles of 94 CRCs and their corresponding normal-appearing colonic mucosa with 11 different markers, including the five classical CIMP markers. The CIMP markers were frequently methylated in proximal CRCs (p < 0.01); however, RASSF1A methylation levels were significantly higher in distal CRCs, the majority of which are CIMP-negative (p < 0.05). Similarly, methylation levels of RASSF1A and SFRP1 in the normal-appearing mucosae of distal CRC cases were significantly higher than those in the proximal CRC cases (p < 0.05). They were also positively correlated with age (RASSF1A, p < 0.01; SFRP1, p < 0.01). Microarray-based genome-wide DNA methylation analysis of 18 CRCs revealed that 168 genes and 720 genes were preferentially methylated in CIMP-negative distal CRCs and CIMP-positive CRCs, respectively. Interestingly, more than half of the hypermethylated genes in CIMP-negative distal CRCs were also methylated in the normal-appearing mucosae, indicating that hypermethylation in CIMP-negative distal CRCs is more closely associated with age-related methylation. By contrast, more than 60% of the hypermethylated genes in CIMP-positive proximal CRCs were cancer specific (p < 0.01). These data altogether suggest that CpG island promoters appear to be methylated in different ways depending on location, a finding which may imply the presence of different mechanisms for the acquisition of epigenetic changes during colon tumorigenesis.

Clinical impact of radiotherapy for locally advanced pancreatic cancer.

BACKGROUND: Although a randomized controlled trial for locally advanced pancreatic cancer (PC) has demonstrated a survival advantage for treatment with gemcitabine alone, chemoradiotherapy remains the treatment of choice for locally advanced disease in Japan. The aim of this study was to compare the survival benefits associated with gemcitabine and concurrent chemoradiotherapy in locally advanced unresectable PC. PATIENTS: Seventy-seven patients with locally advanced unresectable PC were retrospectively enrolled from April 2001 to December 2006. All cases were histologically proven, and patients received gemcitabine chemotherapy (n = 30) or concurrent chemoradiotherapy (based on 5-fluorouracil, n = 28, or gemcitabine, n = 19, as a radiosensitizer) at Aichi Cancer Center Hospital. RESULTS: Patients who received chemoradiotherapy had significantly better performance status than those who had chemotherapy. Tumor response was 0% for chemotherapy and 13% chemoradiotherapy, but survival benefit was similar among patients in the chemotherapy group (overall response (OS) 12 months; progression-free survival (PFS), 3 months) and those in the chemoradiotherapy group (OS, 13 months; PFS, 5 months). Two-year survival was 21% for chemotherapy patients and 19% for chemoradiotherapy patients. Severe toxicities (Grade 3-4 National Cancer Institute-Common Toxicity Criteria, version 3.0) were significantly more frequent for chemoradiotherapy than for chemotherapy. CONCLUSIONS: Gemcitabine chemotherapy showed similar survival benefit compared to 5-fluorouracil- and gemcitabine-based chemoradiotherapy.

Association of prostate stem cell antigen gene polymorphisms with the risk of stomach cancer in Japanese.

A recent whole-genome association study identified a strong association between polymorphisms in the prostate stem cell antigen (PSCA) gene and stomach cancer risk. In this case-control study, we aimed to validate this association, and further to explore environmental factors possibly interacting with PSCA polymorphisms in 708 incident stomach cancer cases and 708 age-sex matched controls. The association between PSCA polymorphisms and Helicobacter pylori infection was also examined. We found that rs2294008 and rs2976392, which were strongly linked to each other (D' = 1.00), were significantly associated with stomach cancer risk. Per allele odds ratio for rs2994008 was 1.40 (95% confidence interval: 1.19-1.65; p = 3.7 x 10(-5)). We found significant interaction with a family history of stomach cancer in first-degree relatives (p-heterogeneity = 0.009). Similar to originally reported association, we found significant heterogeneity between diffuse and intestinal type (p-heterogeneity = 0.007). No association was seen between PSCA polymorphisms and H. pylori infection. In conclusion, PSCA polymorphisms are associated with stomach cancer risk in Japanese. A possible interaction with family history warrants further evaluation.

Syndrome of inappropriate secretion of antidiuretic hormone after endoscopic submucosal dissection for early gastric cancer.

We report the first case of syndrome of inappropriate secretion of antidiuretic hormone (SIADH) after endoscopic submucosal dissection (ESD) for early gastric cancer. A 64-year-old man with early gastric cancer was admitted to our hospital for ESD. Baseline laboratory tests showed a serum sodium concentration of 132 mEq l(-1). We performed an ESD for the gastric cancer, which was 9 mm in diameter and located in the posterior wall of the mid-gastric body. The patient experienced nausea and lethargy the second day after ESD. His serum sodium level was low (118 mEq l(-1)), and he fulfilled the criteria for SIADH. Fluid restriction, infusion of normal saline, and administration of diuretics gradually increased his serum sodium level, and his symptoms disappeared. Endoscopists should recognize that SIADH is a potential complication of endoscopic procedures such as ESD, especially among patients with low baseline sodium concentrations.

Alcohol drinking and one-carbon metabolism-related gene polymorphisms on pancreatic cancer risk.

Effect of alcohol consumption on pancreatic cancer risk has been investigated in many studies, but results have been inconsistent. We conducted a case-control study to assess the effect of alcohol on pancreatic cancer in conjunction with polymorphisms in one-carbon metabolism enzymes, methylenetetrahydrofolate reductase (MTHFR C677T), methionine synthase (MTR A2756G), methionine synthase reductase (MTRR A66G), and thymidylate synthase (TS) variable number of tandem repeat. A total of 157 pancreatic cancer patients and 785 age- and sex- matched control subjects were genotyped for polymorphisms. Odds ratios (OR) with 95% confidence intervals (95% CI) were estimated using unconditional logistic models adjusted for potential confounders. Heavy alcohol drinking was marginally associated with an increased risk of pancreatic cancer (OR, 1.90; 95% CI, 1.00-3.62). None of the polymorphisms showed any significant effect on pancreatic cancer risk by genotype alone. In stratified analysis, effect of alcohol consumption on pancreatic cancer was observed in individuals with the MTHFR 667 CC, MTR 2756 AA, or MTRR 66 G allele. OR (95% CI) of pancreatic cancer for heavy drinkers compared with never drinkers was 4.50 (1.44-14.05) in the MTHFR 667 CC genotype, 2.65 (1.17-6.00) in the MTR 2756 AA genotype, and 3.35 (1.34-8.36) in the MTRR 66 G allele carriers. These results suggest that the folate-related enzyme polymorphism modifies the association between drinking habit and pancreatic cancer risk.

Practical prognostic index for patients with metastatic pancreatic cancer treated with gemcitabine.

AIM: The aim of this study was to identify factors that predict treatment outcome in patients with metastatic pancreatic cancer treated with gemcitabine, and then to use these factors to develop a practical prognostic index. METHODS: A retrospective study was performed on 66 consecutive patients with histologically confirmed pancreatic adenocarcinoma who were treated with gemcitabine. Factors that predicted treatment outcome were identified by univariate and multivariate analyses using the Cox proportional hazards model. RESULTS: Multivariate analysis identified Eastern Cooperative Oncology Group performance status, primary tumor location, and C-reactive protein as important independent predictive factors. Prognostic score was calculated using the following formula: score = (1 if performance status is 0 or 1; 2 if performance status is 2; and 5 if performance status is 3) + (1 if primary site is body or tail, 3 if primary site is head) + (1 if C-reactive protein is <1 mg/dL, 3 if C-reactive protein is 1-3 mg/dL, 6 if C-reactive protein is >3 mg/dL). Patients were accordingly divided into three groups: good (prognostic index = 3 or 4), fair (prognostic index = 5-7), and poor (prognostic index = 8). Median survival was 265, 155, and 65 days for each group, respectively (P < 0.0001). The internally validated c-index (receiver operating characteristics area under the curve) of this model was 0.711. Applied to another data set, the externally validated c-index was 0.692. Prognosis was favorable in the good prognosis group, patients in the fair prognosis group were likely to benefit from gemcitabine, and those in the poor prognosis group were unlikely to benefit. CONCLUSION: This index improved predictive ability in patients with metastatic pancreatic cancer treated with gemcitabine, which may be helpful in counseling patients and making first treatment decisions.

Significance of CXCR3 expression in gastric low-grade B-cell lymphoma of mucosa-associated lymphoid tissue type for predicting responsiveness to Helicobacter pylori eradication.

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct low-grade lymphoma that often regresses upon Helicobacter pylori eradication. It was reported that the chemokine receptor CXCR3 is expressed not only on activated T cells, but also on MALT lymphoma cells, and that CXCR3-positive B lymphocytes migrate or home to the MALT of MALT lymphoma. In the present study, we aimed to elucidate the correlation between CXCR3 expression and the clinicopathological features of gastric MALT lymphoma, and to determine whether CXCR3 expression was predictive of responsiveness to H. pylori eradication. Sixty-seven patients with gastric MALT lymphoma in a single-center study were treated with H. pylori eradication therapy. We evaluated the correlation of CXCR3 expression with response to H. pylori eradication therapy by logistic regression stratified according to potential confounders. Immunohistochemical analysis revealed that 28 of 67 cases (42%) were positive for CXCR3 expression. CXCR3 expression was significantly more prevalent in those without H. pylori infection, advanced-stage disease, and in those with API2-MALT1 fusion. In overall analysis, those with CXCR3 expression showed a significantly increased risk of non-responsiveness to H. pylori eradication therapy (odds ratio = 28.6; 95% confidence interval 5.70-143.4) compared to those without CXCR3 expression. This higher risk was observed consistently regardless of sex, API2-MALT1 fusion, H. pylori infection, or clinical stage. We showed that CXCR3 expression was an independent predictive factor for non-responsiveness to H. pylori eradication therapy in patients with gastric MALT lymphoma.

Genetic variation in PSCA is associated with susceptibility to diffuse-type gastric cancer.

Gastric cancer is classified into intestinal and diffuse types, the latter including a highly malignant form, linitis plastica. A two-stage genome-wide association study (stage 1: 85,576 SNPs on 188 cases and 752 references; stage 2: 2,753 SNPs on 749 cases and 750 controls) in Japan identified a significant association between an intronic SNP (rs2976392) in PSCA (prostate stem cell antigen) and diffuse-type gastric cancer (allele-specific odds ratio (OR) = 1.62, 95% CI = 1.38-1.89, P = 1.11 x 10(-9)). The association was far less significant in intestinal-type gastric cancer. We found that PSCA is expressed in differentiating gastric epithelial cells, has a cell-proliferation inhibition activity in vitro and is frequently silenced in gastric cancer. Substitution of the C allele with the risk allele T at a SNP in the first exon (rs2294008, which has r(2) = 0.995, D' = 0.999 with rs2976392) reduces transcriptional activity of an upstream fragment of the gene. The same risk allele was also significantly associated with diffuse-type gastric cancer in 457 cases and 390 controls in Korea (allele-specific OR = 1.90, 95% CI = 1.56-2.33, P = 8.01 x 10(-11)). The polymorphism of the PSCA gene, which is possibly involved in regulating gastric epithelial-cell proliferation, influences susceptibility to diffuse-type gastric cancer.

Clinical features and prognosis of gastric MALT lymphoma with special reference to responsiveness to H. pylori eradication and API2-MALT1 status.

BACKGROUND AND AIM: Clinicopathologic characteristics and prognosis of Helicobacter pylori eradication-resistant gastric MALT lymphoma have not been well clarified. We analyzed a consecutive series of gastric MALT lymphomas at our institution regarding treatment, clinical course, and prognosis, with special reference to responsiveness to H. pylori eradication and presence of API2-MALT1. METHODS: Subjects were 92 consecutive patients with gastric MALT lymphoma. Seventy were H. pylori positive, and 87 received H. pylori eradication therapy. The remaining five cases were API2-MALT1 positive and did not receive eradication treatment. Second-line treatments were radiation therapy, total gastrectomy, and chemotherapy (rituximab, rituximab plus CHOP, or rituximab plus 2-chlorodeoxyadenosine). RESULTS: Gastric MALT lymphoma was classified into three groups, except one case with API2-MALT1 who responded to H. pylori eradication therapy: responders without API2-MALT1 (group A, N = 56, 65%), nonresponders without API2-MALT1 (group B, N = 16, 19%), and nonresponders with API2-MALT1 (group C, N = 14, 16%). Most cases in group A attained complete remission (CR) in 2 or 3 months and CR persisted for an average of 51.1 months (3-134 months). Recurrence was only seen in one case. In groups B and C, radiation therapy, chemotherapy, and total gastrectomy resulted in CR in 13, 5, and 2 cases, respectively. In 5 group B patients and 6 group C patients who did not undergo second-line therapy, disease did not progress for an average of 10.4 and 40.1 months, respectively. In 1 group C case who did not receive second-line treatment, lymphoma metastasized to the lung 12 yr after eradication. All group B patients and all but 2 group C patients remain alive; one of these deaths was from gastric carcinoma developing 7 yr after eradication. CONCLUSION: Gastric MALT lymphoma responding to H. pylori eradication demonstrated good prognosis, and for nonresponsive cases, second-line treatments resulted in CR. However, careful observation for development of gastric carcinoma and disease progression is essential during follow-up of API2-MALT1-positive MALT lymphoma when patients decline second-line treatment.

Gastric cancer risk and erythrocyte composition of docosahexaenoic acid with anti-inflammatory effects.

Infection with Helicobacter pylori is linked to inflammation and is the main cause of peptic ulcer, gastritis, and gastric malignancies. To examine associations between gastric cancer risk and the erythrocyte composition of docosahexaenoic acid (DHA), a fatty acid with anti-inflammatory and apoptosis-inducing effects, here we conducted a case-control study of 179 incident gastric cancer cases and 357 noncancer controls (matched by age, sex, and season of sample collection). Dietary information and blood samples were collected from all subjects, and erythrocyte fatty acid levels were measured using accelerated solvent extraction and gas-liquid chromatography. Gastric cancer risk did not seem to be directly associated with dietary intake of fish and n-3 highly unsaturated fatty acids (HUFAs), such as DHA, derived from fish. However, risk was inversely associated with erythrocyte compositions of n-3 HUFAs [the highest to the lowest tertile, odds ratio (OR), 0.39; 95% confidence interval (95% CI), 0.23-0.68; P(trend)<0.005] and DHA (OR, 0.47; 95% CI, 0.28-0.79; P(trend)<0.01). Particularly strong associations were noted for well-differentiated type lesions and n-3 HUFAs (OR, 0.10; 95% CI, 0.03-0.35; P(trend)=0.0005) as well as DHA (OR, 0.20; 95% CI, 0.07-0.58; P(trend)<0.01) values. In conclusion, the erythrocyte composition of DHA was found to be negatively linked to risk of gastric cancer, especially of well-differentiated adenocarcinoma. Further studies are needed to investigate mechanisms of action of DHA relevant to antitumor effects in the stomach.

Chromosomal imbalances are associated with outcome of Helicobacter pylori eradication in t(11;18)(q21;q21) negative gastric mucosa-associated lymphoid tissue lymphomas.

Approximately 70% of gastric mucosa-associated lymphoid tissue (MALT) lymphomas can be successfully treated with H. pylori eradication. The translocation t(11;18)(q21;q21) characteristic of MALT lymphoma is recognized as a marker for H. pylori independency, but this marker is found in only a half of the MALT lymphomas resistant to H. pylori eradication. Detailed analyses of the genomic features of eradication resistant as well as responsive groups are important for understanding their molecular basis. We performed array-based comparative genomic hybridization (array-CGH) for 29 gastric MALT lymphomas treated with H. pylori eradication. These comprised ten cases of t(11;18) positive MALT, nine cases of t(11;18) negative MALT with H. pylori dependency, and ten cases of t(11;18) negative MALT with H. pylori independency. Array-CGH analysis demonstrated that no significant genetic alterations were found in t(11;18) positive MALT lymphomas, but numerous genomic alterations were detected in t(11;18) negative MALT lymphomas. Many of these alterations were similar to those found in diffuse large B-cell lymphoma with trisomy 3 being the most recurrent alteration. Within the t(11;18) negative MALT lymphoma without large cell components group, genomic imbalances occurred more frequently in the H. pylori independent than in the H. pylori dependent group (P = 0.02). Genomic imbalances are associated with H. pylori independency in t(11;18) negative gastric MALT lymphomas. They may thus play an important role in the development of H. pylori independency.

Immunoglobulin VH gene analysis in gastric MALT lymphomas.

The majority of gastric mucosa-associated lymphoid tissue (MALT) lymphomas are successfully treated with Helicobacter pylori eradication alone. However, certain subsets of these tumors are resistant to the eradication treatment. As API2-MALT1 fusion is a feature of one of these subsets, we divided gastric MALT lymphomas into three groups: eradication-responsive and API2-MALT1 fusion-negative (Group A), eradication-resistant and fusion-negative (Group B), and eradication-resistant and fusion-positive (Group C). To characterize further gastric MALT lymphomas, we analyzed VH genes, which do not change in the course of tumor progression, by extensive subcloning of the monoclonal PCR products of 45 cases. VH3-23 and VH3-30 were preferentially used in Group A tumors (14/23 cases, 61%) as compared with Group B (1/10 cases, 10%, P=0.0094) and Group C (2/12 cases, 17%, P=0.017). Tumors of Groups B and C used variegated VH fragments, and no dominant VH fragments were noted. Somatic mutation was detected in most of the cases. Ongoing mutation was detected in 3/45 cases (7%), when assessed according to strict criteria for a confirmed mutation. These findings suggest that inflammation-dependent tumors (Group A) may be derived from a highly restricted, probably H. pylori-associated, B cell subset and may not often progress to those that are inflammation-independent (Groups B and C). Although considered to be common in this tumor, ongoing mutation may be infrequent when assessed by strict criteria.

Smoking increases the treatment failure for Helicobacter pylori eradication.

PURPOSE: Treatment failure for Helicobacter pylori (H. pylori) eradication is encountered in approximately 10-20% of patients, and many studies have pointed to a link with smoking. To investigate the effects of smoking on eradication outcome, we performed a meta-analysis. METHODS: A PubMed search was performed to retrieve articles published up to August 2005. Pooled odds ratio (OR) and differences rate for H. pylori eradication failure in smokers compared with nonsmokers were used as summary statistics. Meta-regression was used for examining the source of heterogeneity. RESULTS: Twenty-two published studies (5538 patients), which provided information on eradication failure according to smoking status, were included in the analysis. The summary OR for eradication failure among smokers relative to nonsmokers was 1.95 (95% confidence interval [CI]: 1.55-2.45; P <.01). It corresponds with the differences in eradication rates between smokers and nonsmokers (8.4% [95% CI: 3.3-13.5%, P <.01]). Meta-regression analysis demonstrated that a high proportion of nonulcer dyspepsia patients in studies revealed a higher failure rate among smokers, compared with a low proportion of nonulcer dyspepsia. CONCLUSIONS: Our meta-analysis demonstrated that smoking increases the treatment failure rate for H. pylori eradication.