Evaluation of the dosimetric and radiobiological parameters in four radiotherapy regimens for synchronous bilateral breast cancer.

This study is to investigate the optimal treatment option for synchronous bilateral breast cancer (SBBC) by comparing dosimetric and radiobiological parameters of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) plans using single and dual isocenters. Twenty patients with SBBC without lymph node involvement were selected retrospectively. Four treatment plans were generated for each patient using the Eclipse treatment planning system (Varian Medical System, Palo Alto, CA, USA) following two delivery techniques with two isocenter conditions-IMRT using a single isocenter (IMRT_Iso1), VMAT using a single isocenter (VMAT_Iso1), IMRT using dual isocenters (IMRT_Iso2), and VMAT using dual isocenters (VMAT_Iso2). A dose of 42.56 Gy in 16 fractions was prescribed for the planning target volume (PTV). All plans were calculated using the Acuros XB algorithm and a photon optimizer for a 6-MV beam of a Vital Beam linear accelerator. PTV-related dosimetric parameters were analyzed. Further, the homogeneity index, conformity index, and conformation number were computed to evaluate plan quality. Dosimetric parameters were also measured for the organs at risk (OARs). In addition, the equivalent uniform dose corresponding to an equivalent dose related to a reference of 2 Gy per fraction, the tumor control probability, and the normal tissue complication probability were calculated based on the dose-volume histogram to investigate the radiobiological impact on PTV and OARs. IMRT_Iso1 exhibited similar target coverage and a certain degree of dosimetric improvement in OAR sparing compared to the other techniques. It also exhibited some radiobiological improvement, albeit insignificant. Although IMRT_Iso1 significantly increased monitor unit compared to VMAT_Iso1, which is the best option in terms of delivery efficiency, there was only a 22% increase in delivery time. Therefore, in conclusion, IMRT_Iso1, the complete treatment of which can be completed using a single setup, is the most effective method for treating SBBC.

Colon Polyp Detection in Primary Health Care Institutions of Korea: Detection Rate and Issues with Following the Guidelines.

Background/Aims: There have been few multicenter studies on colonic polyps conducted by primary medical institutions. This study examined the detection rate of colonic polyps in primary health care institutions and the related factors while following the guidelines. Methods: The medical records of 14,029 patients who underwent colonoscopy between January-June 2020 at 40 primary medical institutions in Korea were analyzed. High-risk adenoma was defined as advanced adenoma, carcinoma, or ≥3 adenomas. Results: Most patients (71.2%) aged ≥50 years underwent re-colonoscopy within 5 years (51.3%) for diagnostic purposes (61.3%) in Korean primary medical institutions. The detection rates of colon polyps, adenoma, advanced adenoma, high-risk adenoma, and carcinoma was 59.9%, 38.9%, 5.9%, 11.4%, and 0.3% in all subjects and 59.8%, 37.5%, 8.5%, 12.9%, and 0.3% in average-risk patients, respectively. The incidences of adenoma in average-risk patients increased significantly with age (30s/40s/50s: 20.1%/29.4%/43% for adenoma, 4.4%/6.7%/10.3% for advanced adenoma, and 5.6%/9.5%/14.6% for high-risk adenoma; p<0.05). Before 50 years of age, high-risk adenoma was detected in 9.1% of patients in the first-time screening group, and the significant risk factors were being male and ≥40 years of age. The detection rate of high-risk adenoma in the normal index colonoscopy group within 5 years was 9.0%. The significant risk factors included older age, male sex, positive fecal occult blood test, stool form changes, and nonspecific symptoms (gas and indigestion). Conclusions: More colonic adenoma studies targeting real-world clinical practice will be needed to revise the Korean guidelines for colorectal cancer screening and surveillance.

Extensive Disease Subtypes in Adult Patients with Ulcerative Colitis: Non-pancolitis Versus Pancolitis.

BACKGROUND AND AIM: Few studies have compared pancolitis and non-pancolitis E3 in adult patients with ulcerative colitis (UC). This study aimed to evaluate the natural disease courses and factors affecting outcomes between pancolitis and non-pancolitis E3. METHODS: We retrospectively analyzed 117 patients, including 93 with extensive colitis (E3) and 24 with UC confined to the rectum or left-sided colon and appendiceal orifice inflammation at the time of diagnosis, who were regularly followed up for at least 1 year. Patients with E3 were divided into two groups according to the degree of disease extension: pancolitis group (disease extent up to the cecum or proximal ascending colon) and non-pancolitis E3 group (disease extent above the splenic flexure but not up to the proximal ascending colon). Clinical findings at diagnosis; comorbidity; medications; Mayo score; cumulative rates of corticosteroid, immunomodulator, and anti-tumor necrosis factor (anti-TNF) alpha use; relapse; and admission were compared between the pancolitis and non-pancolitis E3 groups. RESULTS: The median follow-up duration of the 117 patients was 74 (range 15-158) months. Fifty-one patients (43.5%) had pancolitis. The Mayo score at initial diagnosis, cumulative relapse rate, and cumulative admission rate were significantly higher in the pancolitis group than in the non-pancolitis E3 group (P < 0.001, P = 0.023 and P = 0.007, respectively). However, there was no significant difference between the groups in the rates of cumulative immunomodulator and anti-TNF alpha use (P = 0.67 and P = 0.73, respectively). CONCLUSIONS: In patients with extensive UC (E3), pancolitis was associated with higher probabilities of cumulative relapse or admission, indicating poor prognosis.

Aspergillus Tracheobronchitis and Influenza A Co-infection in a Patient with AIDS and Neutropenia.

Aspergillus tracheobronchitis (AT), an unusual form of invasive pulmonary aspergillosis (IPA), is characterized by pseudomembrane formation, ulcer or obstruction that is predominantly confined to tracheobronchial tree. Hematologic malignancies, neutropenia, solid organ transplantation, chronic corticosteroid therapy and acquired immunodeficiency syndrome (AIDS) are known to be major predisposing conditions. However, since the introduction of highly active antiretroviral therapy, there is only one reported case of AT in AIDS patient. After pandemic of influenza A/H1N1 2009, there are several reports of IPA in patient with influenza and most of them received corticosteroid or immunosuppressive therapy before the development of IPA. We present a 45 year-old AIDS patient with influenza A infection who developed pseudomembranous AT without corticosteroid use or immunosuppressive therapy.

Primary tumor maximum standardized uptake value measured on 18F-fluorodeoxyglucose positron emission tomography-computed tomography is a prognostic value for survival in bile duct and gallbladder cancer.

BACKGROUND/AIMS: Few studies have assessed the prognostic value of the primary tumor maximum standardized uptake value (SUV max) measured by 2-[(18)F]-fluoro-2-deoxy-D-glucose PET-CT for patients with bile duct and gallbladder cancer. METHODS: A retrospective analysis of 61 patients with confirmed bile duct and gallbladder cancer who underwent FDG PET-CT in Kangbuk Samsung Medical Center (Seoul, Korea) from April 2008 to April 2011. Prognostic significance of SUV max and other clinicopathological variables was assessed. RESULTS: Twenty-three patients were diagnosed as common bile duct cancer, 17 as hilar bile duct cancer, 12 as intrahepatic bile duct cancer, and nine as gallbladder cancer. In univariate analysis, diagnosis of intrahepatic cholangiocarcinoma and gallbladder cancer, mass forming type, poorly differentiated cell type, nonsurgical treatment, advanced American Joint Committee on Cancer (AJCC) staging and primary tumor SUV max were significant predictors of poor overall survival. In multivariate analysis adjusted for age and sex, primary tumor SUV max (hazard ratio [HR], 4.526; 95% CI, 1.813-11.299), advanced AJCC staging (HR, 4.843; 95% CI, 1.760-13.328), and nonsurgical treatment (HR, 6.029; 95% CI, 1.989-18.271) were independently associated with poor overall survival. CONCLUSIONS: Primary tumor SUV max measured by FDG PET-CT is an independent and significant prognostic factor for overall survival in bile duct and gallbladder cancer.

The influence of waist circumference on insulin resistance and nonalcoholic fatty liver disease in apparently healthy Korean adults.

BACKGROUND/AIMS: Waist circumference (WC) is a risk factor for metabolic syndrome and is related to insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). The purpose of this study was to determine the association between WC and IR and NAFLD in apparently healthy Korean adults. METHODS: The volunteers included in this cross-sectional study comprised 9,159 adults (5,052 men, 4,107 women) who participated in a comprehensive health checkup program. IR was evaluated by the homeostasis model assessment of IR (HOMA-IR) and was considered to be present when the HOMA-IR score was >2. NAFLD was evaluated by ultrasound examination. Elevated alanine aminotransferase (ALT) was defined as >40 IU/L in men and >35 IU/L in women. Logistic regression was performed to determine the odds ratios (ORs) and 95% confidence intervals (95% CIs) for NAFLD, IR, and ALT according to categorized levels of WC. RESULTS: NAFLD was found in 2,553 (27.9%) of the participants (82.6% men, 17.4% women), while IR and elevated ALT were found in 17.2% (68.1% men, 31.9% women) and 10% (83% men, 17% women), respectively. After adjusting for confounding factors, the prevalence of NAFLD, IR, and elevated ALT was significantly associated with increases in WC quartile: highest quartile for NAFLD in men, OR=15.539, 95% CI=12.687-19.033; highest quartile for NAFLD in women, OR=48.732, 95% CI=23.918-99.288 (P<0.001); and highest quartile for IR in men, OR=17.576, 95% CI=13.283-23.255; highest quartile for IR in women, OR=11.078, 95% CI=7.813-15.708 (P<0.001); highest quartile for elevated ALT in men, OR=7.952, 95% CI=6.046-10.459; and highest quartile for elevated ALT in women, OR=8.487, 95% CI=4.679-15.395 (P<0.001). CONCLUSIONS: WC contributes to IR and NAFLD in apparently healthy Korean adults, and thus may be an important factor in the development of IR and NAFLD.