Purpose: Radiotherapy is used to reduce the risk of breast cancer recurrence after surgery, but it is a potential cause of secondary cancer. We validated the risk of secondary cancer in primary breast cancer who received radiotherapy compared with those who did not from a matched cohort using a large-scale observational study of the Observational Health Data Sciences and Informatics (OHDSI) data network. Materials and Methods: A retrospective comparative cohort study using propensity score-matched cohorts was performed using two Observational Medical Outcome Partnership common data model databases, from tertiary general hospitals in South Korea. Among female patients who underwent surgery after the diagnosis of breast cancer, the risk of secondary primary malignant occurrence after 1:1 matching was analyzed. Results: Among 27,078 patients with breast cancer, there was no significant difference in the risk of secondary cancer following radiotherapy in 4,426 patients after 1:1 propensity-score matching. Further, there were no significant differences in the sensitivity analysis according to age, latency period, and number of radiation treatments. Conclusion There was no difference in the risk of secondary cancer in the patients diagnosed with breast cancer depending on whether or not radiotherapy was performed after surgery. In the future, it is necessary to analyze including data generated during cancer treatment.

Background: Dipeptidyl peptidase-4 (DPP4) inhibitors are frequently prescribed for patients with type 2 diabetes; however, their cost can pose a significant barrier for those with impaired kidney function. This study aimed to estimate the economic benefits of substituting non-renal dose-adjusted (NRDA) DPP4 inhibitors with renal dose-adjusted (RDA) DPP4 inhibitors in patients with both impaired kidney function and type 2 diabetes. Methods: This retrospective cohort study was conducted from January 1, 2012 to December 31, 2018, using data obtained from common data models of five medical centers in Korea. Model 1 applied the prescription pattern of participants with preserved kidney function to those with impaired kidney function. In contrast, model 2 replaced all NRDA DPP4 inhibitors with RDA DPP4 inhibitors, adjusting the doses of RDA DPP4 inhibitors based on individual kidney function. The primary outcome was the cost difference between the two models. Results: In total, 67,964,996 prescription records were analyzed. NRDA DPP4 inhibitors were more frequently prescribed to patients with impaired kidney function than in those with preserved kidney function (25.7%, 51.3%, 64.3%, and 71.6% in patients with estimated glomerular filtration rates [eGFRs] of ≥60, <60, <45, and <30 mL/min/1.73 m2, respectively). When model 1 was applied, the cost savings per year were 7.6% for eGFR <60 mL/min/1.73 m2 and 30.4% for eGFR <30 mL/min/1.73 m2. According to model 2, 15.4% to 51.2% per year could be saved depending on kidney impairment severity. Conclusion Adjusting the doses of RDA DPP4 inhibitors based on individual kidney function could alleviate the economic burden associated with medical expenses.

Subdural hematoma (SDH) due to spontaneous rupture of intracranial aneurysm rarely occurs. The prevalence of subarachnoid hemorrhage (SAH) with SDH is approximately 0.5%–10.3% of all aneurysmal SAH. We report a case of aneurysmal rupture with SDH and SAH due to arachnoid defect after aneurysm clipping. The decedent was a 51-year-old woman who underwent brain surgery for SAH a few years ago. Two days before she died, she had nausea and sentinel headache. She was alive in the morning and was found dead at 6 PM. Injuries in the external surface were not found. A fresh SDH, measured approximately 90 mL, was found in the right hemisphere. SAH was diffusely distributed at the base of the brain and the right sylvian fissure. Two aneurysmal clippings were found in the anterior communicating artery and right internal carotid artery. A ruptured de novo aneurysm was also found in the right proximal middle cerebral artery. An uncal herniation was also observed. The cause of death was SAH with SDH due to de novo intracranial aneurysm. The tearing caused by the adhesion between the aneurysm and arachnoid, high blood pressure, and massive bleeding has been thought to be the causative mechanism of aneurysmal SAH with SDH. However, in this case, the arachnoid defect was caused by aneurysmal clipping through pterional approach. This defect served as the passage between the subarachnoid and subdural spaces. The autopsy for recurrent intracranial aneurysm will increase according to the extending life expectancy of patients after aneurysmal clipping.
Aneurysm ; Arachnoid ; Arteries ; Autopsy ; Brain ; Carotid Artery, Internal ; Cause of Death ; Female ; Headache ; Hematoma, Subdural ; Hemorrhage ; Humans ; Hypertension ; Intracranial Aneurysm ; Life Expectancy ; Middle Aged ; Middle Cerebral Artery ; Nausea ; Prevalence ; Rupture ; Rupture, Spontaneous ; Subarachnoid Hemorrhage ; Subdural Space ; Tears

Subdural hematoma (SDH) due to spontaneous rupture of intracranial aneurysm rarely occurs. The prevalence of subarachnoid hemorrhage (SAH) with SDH is approximately 0.5%–10.3% of all aneurysmal SAH. We report a case of aneurysmal rupture with SDH and SAH due to arachnoid defect after aneurysm clipping. The decedent was a 51-year-old woman who underwent brain surgery for SAH a few years ago. Two days before she died, she had nausea and sentinel headache. She was alive in the morning and was found dead at 6 PM. Injuries in the external surface were not found. A fresh SDH, measured approximately 90 mL, was found in the right hemisphere. SAH was diffusely distributed at the base of the brain and the right sylvian fissure. Two aneurysmal clippings were found in the anterior communicating artery and right internal carotid artery. A ruptured de novo aneurysm was also found in the right proximal middle cerebral artery. An uncal herniation was also observed. The cause of death was SAH with SDH due to de novo intracranial aneurysm. The tearing caused by the adhesion between the aneurysm and arachnoid, high blood pressure, and massive bleeding has been thought to be the causative mechanism of aneurysmal SAH with SDH. However, in this case, the arachnoid defect was caused by aneurysmal clipping through pterional approach. This defect served as the passage between the subarachnoid and subdural spaces. The autopsy for recurrent intracranial aneurysm will increase according to the extending life expectancy of patients after aneurysmal clipping.