Advanced ovarian cancer: HRD/BRCA first-line maintenance reasoning

Learning objectives

1. Identify the histology, germline/tumor BRCA, HRD status, and platinum-response inputs needed before first-line ovarian-cancer maintenance selection.
2. Explain why platinum-based induction is the universal first-line backbone and how BRCA / HRD status route the maintenance choice between olaparib, niraparib, bevacizumab, and observation.
3. Recognize parallel obligations — surgical-debulking quality, infection screening, VTE risk, and prior-PARP exposure — that change the maintenance plan without changing the cytotoxic backbone.

At a glance

• High-grade serous histology, germline + tumor BRCA1/2, and HRD assay status are required before any first-line maintenance plan.
• Carboplatin + paclitaxel is the universal cytotoxic backbone; the maintenance decision sits on top of the platinum response.
• BRCA-mutant disease routes to olaparib maintenance (SOLO-1) as the canonical first option; HRD-positive non-BRCA disease pulls niraparib / olaparib combinations into the conversation.
• Suboptimal debulking, prior PARP-inhibitor exposure, and active platinum resistance change the conversation more than HRD score alone.
• This chapter is an OpenOnco-authored learning aid, not official ESMO content or a CME-credit activity.

Diagnostic and biomarker minimum

Before any first-line plan in advanced ovarian cancer the chapter expects confirmed high-grade serous (or otherwise platinum-sensitive) histology, complete germline BRCA1/2 testing, tumor BRCA1/2 testing where the germline result is negative, an HRD assay result interpreted alongside the assay caveat (different vendors, different cut-offs), a documented debulking outcome (R0 vs R1 vs R2 / interval), and baseline organ function. The chapter is explicit that HRD status without BRCA context is incomplete because the routing of olaparib, niraparib, and bevacizumab depends on the combination.

Linked entities

Section sources

• SRC-NCCN-OVARIAN-2025 NCCN Ovarian Cancer
• SRC-ESMO-OVARIAN-2024 ESMO Ovarian Cancer Clinical Practice Guideline

Induction and the platinum-response window

Carboplatin + paclitaxel remains the universal cytotoxic backbone for first-line advanced ovarian cancer in the OpenOnco model. The maintenance decision is made when the patient completes induction and the platinum response is established. Patients who do not respond to platinum re-enter a different algorithm and do not benefit from PARP-inhibitor maintenance in the canonical first-line model. Bevacizumab can begin during induction and continue into maintenance — the chapter is explicit that bevacizumab and PARP inhibitors are not mutually exclusive, particularly for HRD-positive non-BRCA disease.

Linked entities

Section sources

• SRC-NCCN-OVARIAN-2025 NCCN Ovarian Cancer
• SRC-PRIMA-GONZALEZ-MARTIN-2019 Niraparib in Patients with Newly Diagnosed Advanced Ovarian Cancer

Maintenance routing by BRCA + HRD

After response to platinum, OpenOnco routes maintenance choices by combined BRCA / HRD status. BRCA-mutant disease (germline or somatic) routes to olaparib maintenance as the canonical first option (SOLO-1). HRD-positive non-BRCA disease pulls niraparib (PRIMA) and olaparib combinations into the conversation, often with bevacizumab continued from induction. HRD-negative disease without BRCA mutation typically relies on bevacizumab maintenance or observation; the chapter is explicit that adding a PARP inhibitor to HRD-negative non-BRCA disease is not the canonical default.

Linked entities

Section sources

• SRC-SOLO1-MOORE-2018 Maintenance Olaparib in Patients with Newly Diagnosed Advanced Ovarian Cancer
• SRC-PRIMA-GONZALEZ-MARTIN-2019 Niraparib in Patients with Newly Diagnosed Advanced Ovarian Cancer

Common traps

Do not treat the maintenance decision as a single biomarker call. HRD-assay vendor differences and cut-off thresholds change which patients fall on each side of the line — the chapter expects the learner to record which assay was used and to read the report holistically. Suboptimal debulking changes the prognosis but does not by itself remove a PARP-inhibitor option. Prior PARP-inhibitor exposure (rare at first line, common at recurrence) reshapes the maintenance discussion completely. VTE risk and infection screening sit beside the regimen choice and must not be skipped.

Linked entities

Section sources

• SRC-NCCN-OVARIAN-2025 NCCN Ovarian Cancer
• SRC-ESMO-OVARIAN-2024 ESMO Ovarian Cancer Clinical Practice Guideline

Worked synthetic cases

• patient_ovarian_advanced_hrd Advanced HRD-positive ovarian cancer: maintenance reasoning - HRD-driven maintenance routing, platinum-response gating examples/patient_ovarian_advanced_hrd.json
• patient_ovarian_hrd_neg_carbo_pacli_no_parpi HRD-negative ovarian cancer: induction without PARP maintenance - negative-HRD pathway, bevacizumab-only or observation examples/patient_ovarian_hrd_neg_carbo_pacli_no_parpi.json