Is there any impact of PET/CT on radiotherapy planning in rectal cancer patients undergoing preoperative IMRT?

Background/aim: To investigate the effect of positron emission tomography-computed tomography (PET/CT)-based contouring on dosimetric parameters in rectal cancer patients undergoing preoperative intensity-modulated radiation therapy (IMRT). Materials and methods: Preoperative radiation therapy plans with conformal radiotherapy (CRT) or IMRT were created and examined according to the CT-and PET/CT-based contouring of 20 rectal cancer patients, retrospectively. Results: The target volumes delineated with PET/CT were significantly larger than the volumes created by CT (P = 0.043). Dose delivered to 98\% of the planning target volume was high in IMRT planning contouring with CT and PET/CT compared with CRT planning, but the difference was not statistically significant (P = 0.056). Percent volumes receiving 105\% of dose and 110\% of dose were low in IMRT planning when compared with CRT (P < 0.0001 and P = 0.044, respectively). The volumes receiving 45 Gy for the small intestine, femur heads, and bladder and the maximum dose received by the bladder were significantly lower in IMRT. Conclusion: We showed that the target volumes created with PET/CT are significantly larger than the target volumes created with CT and that IMRT provides lower radiation exposure to the tumor-free tissues compared to the CRT planning. The dosimetric results primarily favor IMRT planning in rectal cancer patients and consequently present the significant alteration in target volumes

The Properties of Vitamin B12 Deficiency in the Patients of an Outpatient Clinic

Objective: The aim of this study is to evaluate the properties of vitamin B12 deficiency and predisposing factors in the patients of an outpatient clinic. Material and Methods: Four hundred patients with vitamin B12 deficiency were studied. Anthropometric measures, biochemical analysis, gastric parietal cell antibodies and parasites in stool of the patients, antigliadin antibody survey and upper gastrointestinal system endoscopy were performed. Additionally, randomly selected 100 patients with low and 100 healthy subjects with normal serum vitamin B12 levels were questioned about food intake. Results: Overall ratio of vitamin B12 deficiency among outpatients was 4%. Coexisting diseases such as diabetes mellitus (12.3%), hypertension (42.0%), hyperlipidemia (42.0%) and obesity (42.0%) were determined. Nearly a quarter (22,8%) had autoimmune thyroid disease. A group of patients had other problems that may have caused malabsorption such as Helicobacter pylori gastritis (66/85= 77.6%), antigastric parietal cell antibody positivity (37/85= 43.5%), antigliadin antibody positivity (40/61= 65.6%), and others (3.3%). The patient group with vitamin B12 deficiency consumed significantly less meat (p< 0.001), chicken (p< 0.001), fish (p= 0.002), milk (p= 0.027) and eggs (p< 0.001), smaller number of meals (p= 0.013) and significantly higher amounts of fiber (p< 0.001) and vegetables (p= 0.037) when compared with the control group. Conclusion: Vitamin B12 deficiency was considered to be related mainly with improper and defective alimentation. However, malabsorption-related diseases may also contribute to vitamin B12 deficiency

Management of Polydrug-Resistant Tuberculosis

Background and Objectives: There is a lack of information regarding the effective duration of treatment necessary to prevent the development of acquired resistance when fluoroquinolones (FQ), and/or pyrazinamide (Z) resistance has occurred in patients with polydrug-resistant tuberculosis and isoniazid resistance. The management of these kinds of patients should be carried out in experienced centers according to drug susceptibility test results, clinical status of the patient and the extensity of the disease. Materials and Methods: We evaluated treatment regimens, treatment outcomes, and drug adverse effects in seven patients with polydrug-resistant tuberculosis, including those with Z and/or FQ resistance in a retrospective analysis Results: Regarding the patients with polydrug-resistant tuberculosis in addition to isoniazid (H) resistance, three had Z, two had FQ, and the remaining two had both Z and FQ resistance. In the intensive phase of the treatment, the patients were given at least four drugs according to drug susceptibility tests, and at least three drugs in the continuation phase. The duration of treatment was 9–12 months. Two of the patients were foreign nationals, and could not be followed up with due to returning to their home countries. Regarding the remaining five patients, three of them were terminated as they completed treatment, and two as cured. No recurrence was observed in the first year of the treatment. The most common, and serious drug side effect was seen for amikacin. Conclusions: In patients with polydrug-resistant TB, if Z and/or FQ resistance is detected in addition to H resistance, the treatment of these patients should be conducted on a case-by-case basis, taking into account the patient’s resistance pattern, clinical condition, and disease prognosis. Close monitoring of the side effects will increase the success rate of the treatment