Endometrial cancer is often framed as a postmenopausal disease, yet a growing body of evidence suggests that premenopausal women with polycystic ovary syndrome — now increasingly termed polyendocrine metabolic ovarian syndrome (PMOS) — carry a meaningfully elevated risk, a dimension that a major JAMA review recently left unaddressed. Closing this gap matters because premenopausal endometrial cancer is frequently diagnosed later, when patients and clinicians are less vigilant.
The correspondence flags that PMOS, the most prevalent endocrine disorder among reproductive-aged women, is mechanistically linked to endometrial cancer through estrogen-dependent pathways. The association is most pronounced for low-grade endometrioid carcinomas — a histological subtype characterized by chronic, unopposed estrogen exposure combined with relative progesterone deficiency, a hallmark of anovulatory cycles common in PMOS. The letter draws attention to the omission of this risk factor from an otherwise comprehensive hormonal discussion, arguing that the evidence base is substantial enough to warrant explicit inclusion.
From a broader clinical and research perspective, the PMOS–endometrial cancer link is not new, but it remains underappreciated in standard risk stratification tools. Epidemiological studies have consistently reported a two- to threefold elevated risk among women with PCOS/PMOS compared to matched controls, though most data are observational and confounded by obesity and insulin resistance, which independently drive endometrial proliferation. The renaming from PCOS to PMOS reflects an evolving understanding of the condition as a systemic metabolic disorder, not merely a reproductive one — a reframing that arguably makes the cancer connection more, not less, biologically plausible. This letter is incremental rather than paradigm-shifting, but it serves a useful corrective function: reminding clinicians that endometrial surveillance conversations should begin well before menopause for women with PMOS, particularly those with long histories of anovulation.