Stratifying non-small cell lung cancer patients using an inverse of the treatment decision rules: validation using electronic health records with application to an administrative database.

BACKGROUND: To validate a stratification method using an inverse of treatment decision rules that can classify non-small cell lung cancer (NSCLC) patients in real-world treatment records. METHODS: (1) To validate the index classifier against the TNM 7th edition, we analyzed electronic health records of NSCLC patients diagnosed from 2011 to 2015 in a tertiary referral hospital in Seoul, Korea. Predictive accuracy, stage-specific sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and c-statistic were measured. (2) To apply the index classifier in an administrative database, we analyzed NSCLC patients in Korean National Health Insurance Database, 2002-2013. Differential survival rates among the classes were examined with the log-rank test, and class-specific survival rates were compared with the reference survival rates. RESULTS: (1) In the validation study (N = 1375), the overall accuracy was 93.8% (95% CI: 92.5-95.0%). Stage-specific c-statistic was the highest for stage I (0.97, 95% CI: 0.96-0.98) and the lowest for stage III (0.82, 95% CI: 0.77-0.87). (2) In the application study (N = 71,593), the index classifier showed a tendency for differentiating survival probabilities among classes. Compared to the reference TNM survival rates, the index classification under-estimated the survival probability for stages IA, IIIB, and IV, and over-estimated it for stages IIA and IIB. CONCLUSION: The inverse of the treatment decision rules has a potential to supplement a routinely collected database with information encoded in the treatment decision rules to classify NSCLC patients. It requires further validation and replication in multiple clinical settings.

Complete vaginal outlet stenosis in a patient with Sheehan's syndrome.

We present a case of complete vaginal stenosis in a woman diagnosed with Sheehan's syndrome. The patient delivered at full-term 5 months prior, and experienced massive postpartum bleeding at that time. During evaluation of persistent amenorrhea, we found that her vaginal orifice was completely adhesive and obstructed. Prior to corrective surgery, we managed the patient with an oral contraceptive to induce uterine bleeding into the vaginal outflow tract. After three cycles of an oral contraceptive, we could confirm that there was no stenotic lesion in the vaginal cavity as a hematocolpos was created. Adhesiolysis with scar revision for the vaginal stenosis was successfully performed; it was found that the lesion was limited to only the distal part of the vaginal outlet. Complete vaginal stenosis in reproductive age women with hypopituitarism has not been reported. The artificial induction of hematometrocolpos before surgery was useful in determining the extent of the stenotic lesion, and assured safety.