Abstract Disclosure: S.Y. Rizvi: None. N. Ahmad: None. Title: Unraveling the Enigma: A Multifaceted Presentation of Hormonal Dysregulation in a 37-Year-Old Woman Background: Leydig cell tumors (LCTs) are rare gonadal tumors, arising from the interstitial cells of the testis or, less commonly, the ovary, 0.1%. These tumors are known for their potential to produce androgens, leading to virilization symptoms such as hirsutism. While LCTs are typically benign, they can occasionally exhibit malignant features. Accurate diagnosis and appropriate management are crucial to prevent complications and ensure favorable outcomes. Clinical Case: A 37-year-old, G3P3A0 woman, presented to our endocrinology clinic for a follow-up visit following the removal of a malignant thyroid nodule. During the visit, her endocrinologist noted elevated testosterone levels and worsening hirsutism. She reported mild abdominal pressure but denied other symptoms. She also complained of pain in the lower abdomen, although physical examination findings were limited due to type II obesity. Diagnostic investigations revealed a history of imaging studies, including CT scans and pelvic ultrasounds, demonstrating various findings such as a fibroid uterus, ovarian abnormalities, and a heterogeneous mass in the left adnexa. Laboratory evaluations over time showed fluctuations in androgen levels, with notable values including DHEA-sulfate (137.5 ug/dL), total testosterone (309.6 NG/dL), and free testosterone (12.85 NG/dL). Tumor markers, including CA 19-9= 16 U/mL, CA 125= 23.3 U/mL, CEA = 1.7 NG/mL, and HCG, were unremarkable. Gynae/Oncology was consulted, and she underwent surgical exploration with laparoscopic left oophorectomy. It revealed a Leydig cell tumor without overt malignant features, as confirmed by histopathological examination and immunohistochemical analysis. Her testosterone improved since oophorectomy. Patient undergoes frequent post-op follow up of her testosterone, free+total lc/MS to monitor for hyperandrogenism. Conclusion: This case highlights the importance of considering Leydig cell tumors in the differential diagnosis of hirsutism, particularly in the presence of elevated androgen levels. Multidisciplinary collaboration involving endocrinologists, gynecologists, oncologists, radiologists, and pathologists is essential for accurate diagnosis and optimal management. Surgical resection remains the cornerstone of treatment for Leydig cell tumors, with careful histopathological evaluation necessary to assess for potential malignancy. Long-term follow-up is warranted to monitor for recurrence or metastasis, although the prognosis for benign Leydig cell tumors is generally favorable. Patients with large body habitus may present challenges in physical examination, necessitating reliance on imaging and laboratory studies for diagnostic evaluation. Keywords: hirsutism, testosterone, ovary Presentation: 6/2/2024