Delayed Diagnosis of Adult Granulosa Cell Tumor: Emphasizing the Importance of Comprehensive Ovarian Mass Evaluation and Standardized Laboratory Reporting

Granulosa cell tumors (GCTs) are rare, non-epithelial ovarian tumors that secrete hormones such as estrogen and inhibin. They are classified as either adult GCTs (AGCTs) or juvenile GCTs (JGCTs). Timely detection is essential to control these malignant tumors and minimize the risk of further progression or spread. However, diagnostic challenges exist, as there are no standardized diagnostic criteria or comprehensive laboratory panels for GCT. In this case, a 36-year-old woman experienced a delayed diagnosis of AGCT, which was incidentally found during a routine ovarian cyst removal. A laboratory formatting error, which placed the quantitative value of inhibin B within the "in range" category, affected the patient's management course. This highlights the critical need for standardized diagnostic workups and laboratory result formats to improve the accuracy of diagnoses and prevent delays in treatment. Current diagnostic procedures often include imaging and serum markers such as inhibin B and anti-müllerian hormone (AMH). The lack of standardized diagnostic panels and the absence of clear guidance for non-gynecologic oncologists in diagnosing GCTs may contribute to misdiagnosis and delayed referrals. Recommendations include developing a standardized panel for GCTs, incorporating serum markers such as inhibin B, AMH, and follicle-stimulating hormone, and considering adding testosterone or estradiol levels based on clinical presentation. Additionally, molecular testing for a missense mutation in the <i>FOXL2</i> gene, which is found in most GCTs, should be incorporated if there is a high clinical suspicion for GCT. Laboratory report formatting should also be improved to highlight abnormal results clearly, removing confusing "in range" or "out of range" categories and instead focusing on easily recognizable abnormal values. Formatting of result reports should be clear and personalized to the physician and patient, including highlighted reference intervals based on the range closest to the patient's population. This case exemplifies how standardizing laboratory procedures and diagnostic criteria could lead to better clinical decision-making, timely referrals, and improved patient outcomes in GCT diagnosis and treatment.