Tumor hypoxia, a common feature occurring in nearly all human solid tumors is a major contributing factor for failures of anticancer therapies. Because ionizing radiation depends heavily on the presence of molecular oxygen to produce cytotoxic effect, the negative impact of tumor hypoxia had long been recognized. In this review, we will highlight some of the past attempts to overcome tumor hypoxia including hypoxic radiosensitizers and hypoxia-selective cytotoxin. Although they were (still are) a very clever idea, they lacked clinical efficacy largely because of ‘reoxygenation’ phenomenon occurring in the conventional low dose hyperfractionation radiotherapy prevented proper activation of these compounds. Recent meta-analysis and imaging studies do however indicate that there may be a significant clinical benefit in lowering the locoregional failures by using these compounds. Latest technological advancement in radiotherapy has allowed to deliver high doses of radiation conformally to the tumor volume. Although this technology has brought superb clinical responses for many types of cancer, recent modeling studies have predicted that tumor hypoxia is even more serious because ‘reoxygenation’ is low thereby leaving a large portion of hypoxic tumor cells behind. Wouldn’t it be then reasonable to combine hypoxic radiosensitizers and/or hypoxia-selective cytotoxin with the latest radiotherapy? We will provide some preclinical and clinical evidence to support this idea hoping to revamp an enthusiasm for hypoxic radiosensitizers or hypoxia-selective cytotoxins as an adjunct therapy for radiotherapy.
Anoxia* ; Cytotoxins ; Hope ; Humans ; Oxygen ; Radiation, Ionizing ; Radiotherapy* ; Treatment Outcome ; Tumor Burden

Background: By analyzing small bowel capsule endoscopy (SBCE) performed in two large hospitals in Kazakhstan, we aimed to explore the characteristics of patients representative of Central Asia and the technical characteristics of SBCE. Methods: SBCE cases were retrospectively analyzed. A descriptive analysis was conducted on the patients’ demographic data, diagnosis, and clinical symptoms. The results of SBCE, such as the lesions found, transit time and retention rate in the stomach and small bowel, and bowel visualization quality, were analyzed. Complications related to SBCE were investigated. Results: SBCE was performed in 123 patients. Abdominal pain (81.3%) and chronic diarrhea (66.7%) were the most common symptoms, followed by weight loss (25.2%) and gastrointestinal bleeding (15.4%). The most common disease was Crohn’s disease (52.0%). Definite lesions, such as ulcers, polyps, and bleeding, were identified in 55.3% of patients. SBCE was successfully completed in all cases except for 11 (9.1%). The average small bowel transit time was 4 hours and 28 minutes. Excellent visualization (>75% of mucosa) was reported in 82.5% of patients. No patients experienced complications. Conclusions SBCE performed in Kazakhstan showed a high diagnostic yield with high-quality patient selection and no complications.

Background: By analyzing small bowel capsule endoscopy (SBCE) performed in two large hospitals in Kazakhstan, we aimed to explore the characteristics of patients representative of Central Asia and the technical characteristics of SBCE. Methods: SBCE cases were retrospectively analyzed. A descriptive analysis was conducted on the patients’ demographic data, diagnosis, and clinical symptoms. The results of SBCE, such as the lesions found, transit time and retention rate in the stomach and small bowel, and bowel visualization quality, were analyzed. Complications related to SBCE were investigated. Results: SBCE was performed in 123 patients. Abdominal pain (81.3%) and chronic diarrhea (66.7%) were the most common symptoms, followed by weight loss (25.2%) and gastrointestinal bleeding (15.4%). The most common disease was Crohn’s disease (52.0%). Definite lesions, such as ulcers, polyps, and bleeding, were identified in 55.3% of patients. SBCE was successfully completed in all cases except for 11 (9.1%). The average small bowel transit time was 4 hours and 28 minutes. Excellent visualization (>75% of mucosa) was reported in 82.5% of patients. No patients experienced complications. Conclusions SBCE performed in Kazakhstan showed a high diagnostic yield with high-quality patient selection and no complications.

Background: By analyzing small bowel capsule endoscopy (SBCE) performed in two large hospitals in Kazakhstan, we aimed to explore the characteristics of patients representative of Central Asia and the technical characteristics of SBCE. Methods: SBCE cases were retrospectively analyzed. A descriptive analysis was conducted on the patients’ demographic data, diagnosis, and clinical symptoms. The results of SBCE, such as the lesions found, transit time and retention rate in the stomach and small bowel, and bowel visualization quality, were analyzed. Complications related to SBCE were investigated. Results: SBCE was performed in 123 patients. Abdominal pain (81.3%) and chronic diarrhea (66.7%) were the most common symptoms, followed by weight loss (25.2%) and gastrointestinal bleeding (15.4%). The most common disease was Crohn’s disease (52.0%). Definite lesions, such as ulcers, polyps, and bleeding, were identified in 55.3% of patients. SBCE was successfully completed in all cases except for 11 (9.1%). The average small bowel transit time was 4 hours and 28 minutes. Excellent visualization (>75% of mucosa) was reported in 82.5% of patients. No patients experienced complications. Conclusions SBCE performed in Kazakhstan showed a high diagnostic yield with high-quality patient selection and no complications.

Background: By analyzing small bowel capsule endoscopy (SBCE) performed in two large hospitals in Kazakhstan, we aimed to explore the characteristics of patients representative of Central Asia and the technical characteristics of SBCE. Methods: SBCE cases were retrospectively analyzed. A descriptive analysis was conducted on the patients’ demographic data, diagnosis, and clinical symptoms. The results of SBCE, such as the lesions found, transit time and retention rate in the stomach and small bowel, and bowel visualization quality, were analyzed. Complications related to SBCE were investigated. Results: SBCE was performed in 123 patients. Abdominal pain (81.3%) and chronic diarrhea (66.7%) were the most common symptoms, followed by weight loss (25.2%) and gastrointestinal bleeding (15.4%). The most common disease was Crohn’s disease (52.0%). Definite lesions, such as ulcers, polyps, and bleeding, were identified in 55.3% of patients. SBCE was successfully completed in all cases except for 11 (9.1%). The average small bowel transit time was 4 hours and 28 minutes. Excellent visualization (>75% of mucosa) was reported in 82.5% of patients. No patients experienced complications. Conclusions SBCE performed in Kazakhstan showed a high diagnostic yield with high-quality patient selection and no complications.

Background: Errors in counting spinal segments are common during interventional procedures when there are transitional vertebrae. In this study, we investigated the prevalence of the transitional vertebrae including thoracolumbar transitional vertebra (TLTV) and lumbosacral transitional vertebrae (LSTV). The relationship between the existence of TLTV and abnormal rib count or the existence of LSTV were also evaluated. Methods: The vertebral levels were counted craniocaudally, starting from C1, based on the assumption of 7 cervical, 12 thoracic, and 5 lumbar vertebrae, using whole spine spiral three-dimensional computed tomographic images. The 20th and 25th vertebrae were defined as L1 and S1, respectively. Results: In total, 150 patients had TLTV, with a prevalence of 11.2% (150/1,340). LSTV was observed in 111 of 1,340 cases (8.3%). Sacralization was observed in 68 of 1,340 cases (5.1%) and lumbarization in 43 of 1,340 cases (3.2%). There was a significant relationship between the existence of TLTV and the abnormal rib count (odds ratio [OR]: 117.26, 95% confidence interval [95% CI]: 60.77–226.27; P < 0.001) and LSTV (OR: 7.38, 95% CI: 3.99–13.63; P < 0.001). Conclusions Our study results suggest that patients with TLTV are more likely to have an abnormal rib count or LSTV. If a TLTV or LSTV is seen on the fluoroscopic image, a whole spine image is necessary to permit accurate numbering of the lumbar vertebra.