Prevalence, risk factors, and surveillance patterns for gastric intestinal metaplasia among patients undergoing upper endoscopy with biopsy.

BACKGROUND AND AIMS: Gastric intestinal metaplasia (GIM) is an important precursor lesion to gastric cancer (GC), the second leading cause of cancer death worldwide. There exist few data regarding the prevalence of, risk factors for, and clinical practice patterns regarding GIM in the United States. Furthermore, there are currently no U.S. guidelines regarding screening/surveillance for GIM. METHODS: All consecutive upper endoscopic procedures from 2 academic medical centers in Seattle between 1999 and 2014 were reviewed. Demographic, clinical, and endoscopic covariates were recorded at time of endoscopy. Procedures with gastric biopsy were matched to final the histologic diagnoses, including the presence of Helicobacter pylori. Cases of GIM and dysplasia were recorded and compared with non-GIM controls using univariate and multivariable regression. Surveillance patterns for cases of GIM were recorded. RESULTS: Data from 36,799 upper endoscopies, 17,710 gastric biopsies, 2073 cases of GIM, 43 cases of dysplasia, and 78 cases of GC were captured. The point prevalence of GIM was 11.7% in patients who underwent gastric biopsy. Non-white race (P < .001), increasing age (P < .001), and presence of H pylori (P < .001) were associated with GIM. If GIM was present, increasing age (P < .001) and male gender (P < .001) were associated with progression, and the presence of H pylori (P < .001) was inversely associated with progression to dysplasia/GC. Few cases of GIM/dysplasia/GC were identified during procedures for GIM screening/surveillance. Only 16% of patients with a diagnosis of GIM received a recommendation for surveillance. CONCLUSIONS: There is a high prevalence of GIM among non-white and Hispanic Americans. Risk factors for development of GIM may be distinct from the risk factors for progression to GC.

Hyperthermia-enhanced targeted drug delivery using magnetic resonance-guided focussed ultrasound: a pre-clinical study in a genetic model of pancreatic cancer.

PURPOSE: The lack of effective treatment options for pancreatic cancer has led to a 5-year survival rate of just 8%. Here, we evaluate the ability to enhance targeted drug delivery using mild hyperthermia in combination with the systemic administration of a low-temperature sensitive liposomal formulation of doxorubicin (LTSL-Dox) using a relevant model for pancreas cancer. MATERIALS AND METHODS: Experiments were performed in a genetically engineered mouse model of pancreatic cancer (KPC mice: LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre). LTSL-Dox or free doxorubicin (Dox) was administered via a tail vein catheter. A clinical magnetic resonance-guided high intensity focussed ultrasound (MR-HIFU) system was used to plan treatment, apply the HIFU-induce hyperthermia and monitor therapy. Post-therapy, total Dox concentration in tumour tissue was determined by HPLC and confirmed with fluorescence microscopy. RESULTS: Localized hyperthermia was successfully applied and monitored with a clinical MR-HIFU system. The mild hyperthermia heating algorithm administered by the MR-HIFU system resulted in homogenous heating within the region of interest. MR-HIFU, in combination with LTSL-Dox, resulted in a 23-fold increase in the localised drug concentration and nuclear uptake of doxorubicin within the tumour tissue of KPC mice compared to LTSL-Dox alone. Hyperthermia, in combination with free Dox, resulted in a 2-fold increase compared to Dox alone. CONCLUSION: This study demonstrates that HIFU-induced hyperthermia in combination with LTSL-Dox can be a non-invasive and effective method in enhancing the localised delivery and penetration of doxorubicin into pancreatic tumours.

Adaptations of an RNA virus to increasing thermal stress.

Environments can change in incremental fashions, where a shift from one state to another occurs over multiple organismal generations. The rate of the environmental change is expected to influence how and how well populations adapt to the final environmental state. We used a model system, the lytic RNA bacteriophage Φ6, to investigate this question empirically. We evolved viruses for thermostability by exposing them to heat shocks that increased to a maximum temperature at different rates. We observed increases in the ability of many heat-shocked populations to survive high temperature heat shocks. On their first exposure to the highest temperature, populations that experienced a gradual increase in temperature had higher average survival than populations that experienced a rapid temperature increase. However, at the end of the experiment, neither the survival of populations at the highest temperature nor the number of mutations per population varied significantly according to the rate of thermal change. We also evaluated mutations from the endpoint populations for their effects on viral thermostability and growth. As expected, some mutations did increase viral thermostability. However, other mutations decreased thermostability but increased growth rate, suggesting that benefits of an increased replication rate may have sometimes outweighed the benefits of enhanced thermostability. Our study highlights the importance of considering the effects of multiple selective pressures, even in environments where a single factor changes.