Personalized Medicine: A New Way to Understand Endometriosis

Endometriosis affects one in 10 women and people with a uterus, yet diagnosis and treatment have seen little progress in three decades. Patients face a 7 to 10 year delay from their first symptoms to a diagnosis, because those symptoms overlap with other conditions, because endometriosis has long been treated as a purely gynecologic disease, and because, until very recently, there was no non-invasive way to detect it at all.

So, how do we move the field forward and improve care for the 190 million people worldwide living with endometriosis? A large part of the answer is personalized medicine.

Lessons From Oncology

While endometriosis is not cancer, and lesions are not tumors, endometriotic lesions appear to share features with cancerous tumors. A 2024 study looked at endometriosis one cell at a time in a preclinical mouse model and found that the immune cells inside lesions, called macrophages, sorted into subtypes that resemble two kinds seen in cancer: tumor-associated and scar-associated macrophages. One subtype encourages new blood vessel growth and tissue remodeling, while the other drives fibrosis, or scarring. A separate group of protective macrophages in the abdominal cavity, marked by a protein called ApoE, appeared to hold lesion growth back. When the researchers gave mice an ApoE-mimicking treatment, lesions shrank and scarring eased, and they compared the mouse and human data to see how well the findings might carry over.¹

This is not the first time endometriosis research has borrowed from oncology. In 2017, sequencing of deep infiltrating endometriosis lesions showed that roughly a quarter carried mutations in known cancer driver genes (KRAS, PIK3CA, ARID1A, and PPP2R1A).² It is a finding that reframes how we think about the biology of so-called benign diseases like endometriosis.

Single-cell studies of the uterine lining point in the same direction. Research comparing menstrual tissue from people with and without endometriosis found that in those with the disease, the stromal cells of the lining were less able to go through decidualization, the normal monthly change that prepares the lining for a possible pregnancy. The same tissue showed a sharp drop in uterine natural killer cells, immune cells that help keep the lining healthy, and its stromal cells were enriched for inflammatory and senescent, or prematurely aged, signatures. Together these point to chronic, low-grade inflammation.³ A separate large-scale atlas of more than 300,000 cells from 63 people singled out decidualized stromal cells and macrophages as the cell types most closely tied to the genetic risk of endometriosis.⁴

The Gaps That Remain

Despite these insights, the tools in everyday use still treat endometriosis as a single condition. Non-invasive tests that can flag whether endometriosis is likely present are finally reaching clinics, and in 2026 NICE recommended two of them for use in the NHS.⁵ But these tests answer only whether the disease is there. They do not reveal what kind of endometriosis a patient has, or what is driving it.

Treatments like hormonal suppression and surgical excision still manage symptoms rather than the underlying biology, and the disease returns in 20 to 50 percent of patients after surgery.⁶

A 2021 systematic review and meta-analysis found that taking hormonal suppression after surgery cut the risk of recurrence roughly in half compared with no medication.⁷ It helps, but it manages the disease rather than explaining why a given patient’s endometriosis behaves the way it does, and it does not work for everyone.

The disease’s heterogeneity, its different lesion locations, immune profiles, and genetic risk factors, is a large part of why one-size-fits-all care so often falls short, and why research funding has lagged behind the true burden of the disease.

The Perita Approach

We need to move beyond surgical staging toward personalized medicine, guided by a patient’s molecular, genetic, and tissue biology. A personalized approach to endometriosis could sort patients by the biology actually driving their disease, using markers in blood, endometrial tissue, or other fluids that reflect specific immune or stromal cell patterns, and that information could inform a physician’s decisions.

At Perita, this is the approach we are building. We use precision tools to analyze endometriosis down to individual cells and where they sit in the tissue, producing Deep Endometriosis Characterization™ for a disease that has gone undercharacterized for far too long.

We carry out that in-depth analysis and deliver the results to the treating physician, who uses them as a scientific basis for her own clinical judgment. Each patient also contributes to a longitudinal, multi-omic dataset, building a resource for future research while informing care today.

Endometriosis has waited a long time for the advanced tools that other fields already take for granted. Personalized medicine is the framework that can finally bring them to bear.

Click here to refer a patient for Deep Endometriosis Characterization™.

Perita’s analytical work is investigational and is not an established clinical diagnostic test. Perita makes no claim about the safety or efficacy of any test, analytical approach, or treatment for any patient. All treatment decisions rest with the patient’s treating physician.

References

1. Henlon Y, Panir K, McIntyre I, et al. Single-cell analysis identifies distinct macrophage phenotypes associated with prodisease and proresolving functions in the endometriotic niche. Proceedings of the National Academy of Sciences. 2024;121(38):e2405474121. doi:10.1073/pnas.2405474121

2. Anglesio MS, Papadopoulos N, Ayhan A, et al. Cancer-Associated Mutations in Endometriosis without Cancer. New England Journal of Medicine. 2017;376(19):1835-1848. doi:10.1056/NEJMoa1614814

3. Shih AJ, Adelson RP, Vashistha H, et al. Single-cell analysis of menstrual endometrial tissues defines phenotypes associated with endometriosis. BMC Medicine. 2022;20(1):315. doi:10.1186/s12916-022-02500-3

4. Marečková M, Garcia-Alonso L, Moullet M, et al. An integrated single-cell reference atlas of the human endometrium. Nature Genetics. 2024;56:1925-1937. doi:10.1038/s41588-024-01873-w

5. National Institute for Health and Care Excellence (NICE). New technologies could help cut years-long wait for endometriosis diagnosis. Draft early use healthtech guidance. Published July 7, 2026. https://www.nice.org.uk/news/articles/new-technologies-for-endometriosis-diagnosis-in-primary-care

6. Guo SW. Recurrence of endometriosis and its control. Human Reproduction Update. 2009;15(4):441-461. doi:10.1093/humupd/dmp007

7. Zakhari A, Delpero E, McKeown S, Tomlinson G, Bougie O, Murji A. Endometriosis recurrence following postoperative hormonal suppression: a systematic review and meta-analysis. Human Reproduction Update. 2021;27(1):96-107. doi:10.1093/humupd/dmaa033