Abstract 3065: Increased longevity and quality of life with treatment with a progesterone receptor modulator in a patient with treatment resistant stage IV small cell lung cancer
Authors: Check Jerome H. , Wilson Carrie , Check Diane , Poretta Trina , Srivastava Maya 
Published: April 2023

The progesterone receptor modulator, mifepristone, has been found to provide extension of life by years and marked palliative benefits in several cases of non-small cell lung cancer (NSCLC) despite progression with platinum-based chemotherapy, check-point inhibitors, and third-generation tyrosine inhibitors. Presented here is a case of small cell lung cancer (SCLC) treated with mifepristone. This patient was diagnosed at age 58 with stage IV NSCLC with EGFR deletion 19 mutation. He was treated with single agent osimertinib 80mg once/day. Two months later his serial CT scan showed improvement. He was treated with stereotactic ablative radiotherapy for one persisting lesion. He was able to conduct a very active life. However, clinical symptoms started to return after 8 months, and CT of the chest showed slightly increased size of a the previously treated right upper lobe mass with increased small right effusion, increased pleural nodularity, and new interlobular septal thickening. Biopsy of the pleural mass showed transformation to SCLC. He failed a clinical trial. He began mifepristone orally 200mg/day. Within 1 month he was able to resume normal activity including strenuous sports. CT scans 2 months later showed no longer any pleural effusions, pleural nodularity, or growth of the persisting nodule that had been previously radiated. His absence of clinical symptoms continued for 10 more months but CT now showed slight growth of the persisting lesion. He assumed that with the growth that mifepristone was losing its effectiveness, and after consultation with another oncologist, elected to be treated in another clinical study for a new promising drug for SCLC that precluded him from continuing mifepristone. He died 5 months later. The main benefit of mifepristone is believed to be by blocking membrane rather than nuclear progesterone receptors (PRs) that are responsible for producing an immunosuppressive protein called the progesterone induced blocking factor which allows various cancers to spread. A previous case of stage IV NSCLC without any tumor markers treated with mifepristone had no growth and good health x 2 ½ years when 1 lesion begins to grow slowly. His oncologist suggested stopping mifepristone and try a check-point inhibitor. Instead, he continued mifepristone. He died 3 years later from pneumonia still feeling quite well while the one lesion continued to grow slowly. Another case of rapidly progressing lung cancer diagnosed by CT scan corrected her severe hypoxia (PO2 70 mmHg) and hyponatremia (serum Na+ of 118 mmol/L) after 1 month of taking mifepristone. Her lesions mostly disappeared and 5 years later she died of a myocardial infarction. Though clinically suspicious of SCLC, it was not biopsy proven. Hopefully this case will inspire a clinical trial of PR antagonists for SCLC.

Citation Format: Jerome H. Check, Carrie Wilson, Diane Check, Trina Poretta, Maya Srivastava. Increased longevity and quality of life with treatment with a progesterone receptor modulator in a patient with treatment resistant stage IV small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3065.