Recurrent epithelial ovarian cancer is a sequencing problem. CTC-guided therapy is one of the few published ways to make that sequence less blind.
Hong Kong context Ovarian and peritoneal cancer was the sixth most common cancer in Hong Kong women in 2023, with 623 new cases. It was also the sixth leading cause of female cancer death in 2024 (274 deaths). Most women are still diagnosed at an advanced stage. |
Why this cancer is hard to manage with a single protocol
First-line care is relatively standardised: cytoreductive surgery plus platinum-taxane, with maintenance PARP inhibition for many. After that, platinum-sensitive versus platinum-resistant status drives the next choice — and then the disease becomes a series of shorter responses.
CA125 is a good companion when it tracks disease and a poor one when it does not. Imaging under-calls miliary peritoneal disease. Tissue from the original operation may be two or three lines out of date.
RGCC SEA has already published a blog piece on CTCs and chemotherapy selection in epithelial ovarian cancer. Separately, a 2025 retrospective analysis on tailoring treatment for advanced or recurrent ovarian cancer using CTC response reported longer progression-free survival on the CTC-guided line than on the patient’s previous line, and longer overall survival versus patients who were tested but not treated according to the CTC result. That paper should be cited, not oversold: it is retrospective, and it is the right evidence posture for this article.
What circulating tumor cells add
CTCs in ovarian cancer can be counted, phenotyped and tested for drug sensitivity. Because peritoneal disease sheds into blood as well as ascites, a peripheral-blood assay is usable even when there is no bulky target for biopsy.
Oncotrace is the usual monitoring panel (ovary is not one of the named Oncotrail disease panels). Onconomics Plus is the panel to draw when the next line is being chosen — platinum rechallenge, pegylated liposomal doxorubicin, weekly paclitaxel, gemcitabine, topotecan, bevacizumab combinations, or a PARP decision that still has room to move.
The RGCC pathway for this cancer
A typical sequence is screening or baseline first, then a comprehensive profile when treatment choices matter, then serial follow-up. The exact panel is chosen by the accredited practitioner.
Clinical question | RGCC test to consider |
Family risk (BRCA, Lynch) without a diagnosis | Onco-D-clare as an adjunct only; it does not replace risk-reducing surgery counselling or TVUS / CA125 protocols |
Confirmed epithelial ovarian / fallopian / primary peritoneal cancer; baseline and monitoring | Oncotrace or Oncocount |
Choosing the next line in platinum-sensitive or platinum-resistant recurrence | Onconomics Plus |
Need homologous-recombination or broader mutational context from CTCs | CAMBISeq, alongside germline and tumour BRCA / HRD results |
Immune context before an integrative or IO-containing plan | Immune-Frame |
What the report can change in practice
The practical win is at recurrence. Instead of defaulting to the next drug on a list, the team can see which remaining agents still induce apoptosis in the cells that are circulating now. That is also the point at which many women in Asia start asking about natural compounds; the Extracts panel makes that discussion specific.
During maintenance, a quiet CTC count with low stemness is reassuring when CA125 is fidgety. A rising count is a reason to image earlier.
Link this article internally to the existing RGCC SEA post “Circulating tumor cells: Revolutionizing chemotherapy selection in epithelial ovarian cancer” rather than repeating it.
Who this article is for
• Women with newly diagnosed advanced epithelial ovarian cancer who want a baseline before chemotherapy.
• Anyone facing platinum-sensitive or platinum-resistant recurrence.
• Patients whose CA125 and CT/MRI do not agree.
• BRCA / HRD-positive patients considering the timing of PARP therapy, as one extra data layer.
Next step
Bring your operative histology, BRCA / HRD status, CA125 trend and a list of every regimen already used. An RGCC-accredited practitioner can decide whether to draw Oncotrace alone or Onconomics Plus before the next line starts.
Disclaimer. This article is educational and is intended for patients, families, and referring practitioners. RGCC tests are laboratory investigations that support clinical decision-making. They do not replace imaging, tissue diagnosis, or a treating oncologist’s judgement. Results must be interpreted by an RGCC-accredited practitioner in the context of the full medical history. RGCC circulating tumor cell (CTC) assays are not designed to detect primary cancers of the brain or central nervous system. Always discuss findings with your own doctor before changing any treatment.