BACKGROUNDProstate cancer is the most frequent malignancy among men nowadays.METHODSImmunohistochemical expression of prostate-specific antigen (PSA) was retrospectively investigated in 10 patients admitted with clinical suspicion of the prostate cancer. Slides were collected from archived biopsiesandthey were stained for PSA.The final reaction product was evaluated as negative (0), weak/moderate positive (1), and intense positive (2).RESULTSGlandular prostate carcinoma was found in 40% (n=4) and undifferentiated carcinoma in 60% (n=6). The immunoreaction for PSA was intense positive in 30% (n=3), weak/moderate positive in 50% (n=5) and negative in 20% (n=2) of total cases.CONCLUSIONSWe concludethat PSA immunoreaction is helpful for the differential diagnosis based on our results.

Background: Small intestinal bacterial overgrowth (SIBO) is characterized by symptoms such as malabsorption, nutrient deficiencies, bloating, and abdominal pain. It can occur independently or in association with other gastrointestinal disorders. This study aims to determine the prevalence of SIBO in patients with digestive complaints, evaluate diagnostic outcomes, and analyze the composition and types of pathogenic bacteria present in the small intestine. Materials and Methods: A single-center, cross-sectional study was conducted at the Mongolian-Japanese Hospital, enrolling a total of 46 participants. SIBO was diagnosed using the hydrogen breath test (H₂BT) with lactulose/glucose as substrates. Among the 27 diagnosed cases, 5 patients were randomly selected for microbiological analysis of small intestinal contents. Results: SIBO was detected in 58.7% of the study participants. Among the 5 patients who underwent microbiological analysis, 80% (4/5) tested positive for pathogenic bacteria. The identified pathogens included: Gram-positive bacteria: Staphylococcus aureus (S. aureus); Gram-negative bacteria: Klebsiella pneumoniae (K. pneumoniae); Antibiotic-resistant bacteria: Methicillin-resistant Staphylococcus aureus (MRSA); Fungi: Candida albicans (C. albicans). The remaining 20% (1/5) had a baseline H₂BT value exceeding twice the standard threshold despite no detected pathogens. Conclusion SIBO is highly prevalent among patients with digestive complaints and may be associated not only with bacterial infections but also fungal overgrowth. Therefore, a multidisciplinary treatment approach, including antibiotics, dietary modifications, probiotics, and antifungal therapy, is necessary. While the hydrogen breath test is an effective diagnostic tool for SIBO, standardization of diagnostic protocols is required for improved accuracy.