Plasma testosterone and sex hormone-binding globulin concentrations and the risk of prostate cancer among Japanese men: a nested case-control study

Sex hormones, particularly androgens, have been implicated in prostate carcinogenesis. Overall, however, prospective studies have reported no association between circulating levels of sex hormones and the risk of prostate cancer. However, despite the possible difference in the effects of hormones on prostate cancer risk by stage, age, body mass index (BMI) and isoflavones, evidence for these is sparse. Moreover, few studies have been conducted in Asian populations, who are relatively lean and have high isoflavone consumption. We examined the hypothesis that plasma concentrations of circulating testosterone and sex hormone-binding globulin (SHBG) are associated with the risk of prostate cancer in a case-control study nested in the Japan Public Health Center-based Prospective Study. Concentrations of total testosterone and SHBG were measured in plasma samples from 201 patients with prostate cancer and 402 matched control participants, and concentrations of free testosterone were calculated. No overall association between the plasma levels of any hormone and total prostate cancer was observed. Odds ratios (95% confidence interval [CI]) in the highest versus lowest group were 0.71 (95% CI = 0.36-1.41, Ptrend = 0.43) for total testosterone, 0.70 (95% CI = 0.39-1.27, Ptrend = 0.08) for free testosterone and 1.38 (95% CI = 0.69-2.77, Ptrend = 0.23) for SHBG. When stratified by cancer stage, age, BMI and plasma isoflavone level, free testosterone was inversely associated with localized cancers and equol producers, while SHBG was associated with an increased risk of prostate cancer in younger men. In conclusion, in this nested case-control study, concentrations of circulating total testosterone, free testosterone or SHBG were not strongly associated with a risk for total prostate cancer.     

A case of 10-year survival after combination chemotherapy of 5'-deoxy-5-fluorouridine and cisplatin and adjuvant surgery for gastric cancer with liver metastasis

A 36-year-old woman was diagnosed with type 3 advanced gastric cancer with multiple liver metastases in March 1992. The patient was treated with systemic chemotherapy of 5'-deoxy-5-fluorouridine and cisplatin. After 4 courses of chemotherapy, the primary lesion responded and the multiple liver metastases disappeared. Therefore, total gastrectomy with perigastric lymphadenectomy and splenic preservation was performed. Two additional courses of the same chemotherapy were administered after the surgery. The patient has been alive without recurrence for 10 years after the curative resection.     

<Superscript>18</Superscript>F-FDG PET radiomics approaches: comparing and clustering features in cervical cancer

Objectives

The aims of our study were to find the textural features on ¹⁸F-FDG PET/CT which reflect the different histological architectures between cervical cancer subtypes and to make a visual assessment of the association between ¹⁸F-FDG PET textural features in cervical cancer.

Methods

Eighty-three cervical cancer patients [62 squamous cell carcinomas (SCCs) and 21 non-SCCs (NSCCs)] who had undergone pretreatment ¹⁸F-FDG PET/CT were enrolled. A texture analysis was performed on PET/CT images, from which 18 PET radiomics features were extracted including first-order features such as standardized uptake value (SUV), metabolic tumor volume (MTV) and total lesion glycolysis (TLG), second- and high-order textural features using SUV histogram, normalized gray-level co-occurrence matrix (NGLCM), and neighborhood gray-tone difference matrix, respectively. These features were compared between SCC and NSCC using a Bonferroni adjusted P value threshold of 0.0028 (0.05/18). To assess the association between PET features, a heat map analysis with hierarchical clustering, one of the radiomics approaches, was performed.

Results

Among 18 PET features, correlation, a second-order textural feature derived from NGLCM, was a stable parameter and it was the only feature which showed a robust trend toward significant difference between SCC and NSCC. Cervical SCC showed a higher correlation (0.70 ± 0.07) than NSCC (0.64 ± 0.07, P = 0.0030). The other PET features did not show any significant differences between SCC and NSCC. A higher correlation in SCC might reflect higher structural integrity and stronger spatial/linear relationship of cancer cells compared with NSCC. A heat map with a PET feature dendrogram clearly showed 5 distinct clusters, where correlation belonged to a cluster including MTV and TLG. However, the association between correlation and MTV/TLG was not strong. Correlation was a relatively independent PET feature in cervical cancer.

Conclusions

¹⁸F-FDG PET textural features might reflect the differences in histological architecture between cervical cancer subtypes. PET radiomics approaches reveal the association between PET features and will be useful for finding a single feature or a combination of features leading to precise diagnoses, potential prognostic models, and effective therapeutic strategies.

     

Characteristics of Classical Swine Fever Virus Variants Derived from Live Attenuated GPE− Vaccine Seed

The GPE⁻ strain is a live attenuated vaccine for classical swine fever (CSF) developed in Japan. In the context of increasing attention for the differentiating infected from vaccinated animals (DIVA) concept, the achievement of CSF eradication with the GPE⁻ proposes it as a preferable backbone for a recombinant CSF marker vaccine. While its infectious cDNA clone, vGPE⁻, is well characterized, 10 amino acid substitutions were recognized in the genome, compared to the original GPE⁻ vaccine seed. To clarify the GPE⁻ seed availability, this study aimed to generate and characterize a clone possessing the identical amino acid sequence to the GPE⁻ seed. The attempt resulted in the loss of the infectious GPE⁻ seed clone production due to the impaired replication by an amino acid substitution in the viral polymerase NS5B. Accordingly, replication-competent GPE⁻ seed variant clones were produced. Although they were mostly restricted to propagate in the tonsils of pigs, similarly to vGPE⁻, their type I interferon-inducing capacity was significantly lower than that of vGPE⁻. Taken together, vGPE⁻ mainly retains ideal properties for the CSF vaccine, compared with the seed variants, and is probably useful in the development of a CSF marker vaccine.     

Alcohol drinking and colorectal cancer in Japanese: a pooled analysis of results from five cohort studies

Colorectal cancer is an alcohol-related malignancy; however, the association appears to be stronger among Asian populations with a relatively high prevalence of the slow-metabolizing aldehyde dehydrogenase variant. To examine the association between alcohol consumption and colorectal cancer in Japanese, the authors analyzed original data from five cohort studies that measured alcohol intake using validated questionnaires at baseline. Hazard ratios were calculated in the individual studies, with adjustment for a common set of variables, and then combined using a random-effects model. During 2,231,010 person-years of follow-up (ranging variously from 1988 to 2004), 2,802 colorectal cancer cases were identified. In men, multivariate-adjusted pooled hazard ratios for alcohol intakes of 23-45.9 g/day, 46-68.9 g/day, 69-91.9 g/day, and > or =92 g/day, compared with nondrinking, were 1.42 (95% confidence interval (CI): 1.21, 1.66), 1.95 (95% CI: 1.53, 2.49), 2.15 (95% CI: 1.74, 2.64), and 2.96 (95% CI: 2.27, 3.86), respectively (p for trend < 0.001). The association was evident for both the colon and the rectum. A significant positive association was also observed in women. One fourth of colorectal cancer cases in men were attributable to an alcohol intake of > or =23 g/day. An alcohol-colorectal cancer association seems to be more apparent in Japanese than in Western populations. Whether this difference can be ascribed to genetic or environmental factors needs to be clarified.