A winding path through a field of stylized flowers, symbolizing hope and growth in ovarian cancer treatment.

Low-Grade Serous Ovarian Cancer: A Comprehensive Guide

Jordan Keane in Health & Wellness December 2025 • 4 min read.

"Understanding, managing, and living with this rare ovarian cancer subtype"

Ovarian cancer ranks as the second most lethal gynecological malignancy, demanding increased awareness and targeted strategies. While various types exist, this article focuses on low-grade serous ovarian carcinoma (LGSOC), a distinct subtype requiring specialized care. The World Health Organization classifies ovarian cancers into epithelial, non-epithelial, and metastatic types. Among these, serous ovarian carcinoma is further divided into high-grade serous (HGSOC) and low-grade serous ovarian carcinoma (LGSOC).

The distinction between HGSOC and LGSOC is critical. In 2004, a two-tier system based on nuclear atypia was introduced, leading to the recognition of LGSOC as a separate entity with unique genetic and clinical characteristics. LGSOC accounts for only 5-10% of serous ovarian carcinomas, presenting unique challenges in research and treatment due to its relative rarity.

This article aims to provide a comprehensive overview of LGSOC, translating complex research into accessible information for patients, families, and healthcare professionals. We will explore the diagnosis, treatment, and management of LGSOC, highlighting the latest findings and strategies for improving outcomes.

Navigating LGSOC: Diagnosis, Treatment, and Management

A winding path through a field of stylized flowers, symbolizing hope and growth in ovarian cancer treatment.

Diagnosing LGSOC typically involves a combination of clinical evaluation, imaging, and histological assessment. Patients often present with symptoms similar to other ovarian cancers, such as abdominal or pelvic pain, bloating, or bowel dysfunction. Diagnostic workup includes a pelvic exam, CA125 blood test, and imaging studies like ultrasound or CT scans. LGSOC can arise de novo or from a serous borderline tumor (sBOT).

A significant portion of LGSOC cases (around 60%) are linked to a history of serous borderline tumors (sBOT), suggesting a potential developmental relationship. Gene expression profiling supports this theory, indicating that sBOT can transform into LGSOC. Current classifications recognize sBOT with invasive implants as low-grade carcinomas. While transformation from low-grade to high-grade serous cancer is rare, understanding these pathways is crucial for effective management.

Surgery: Aim for complete resection during primary cytoreductive surgery. If complete resection isn't possible initially, neoadjuvant chemotherapy followed by interval debulking surgery may be considered. Microscopic residual disease after surgery leads to better overall survival.
Chemotherapy: Adjuvant chemotherapy is generally recommended, though LGSOC is less chemo-sensitive than HGSOC. For advanced cases, regimens containing carboplatin and paclitaxel are used.
Hormonal Therapy: LGSOC often expresses estrogen and progesterone receptors, making hormonal therapy a viable option. Studies suggest hormonal maintenance therapy after chemotherapy improves progression-free survival.
Targeted Therapies: Given the prevalence of KRAS/BRAF/MAPK pathway mutations, targeted agents are being investigated. MEK inhibitors have shown promise in clinical trials.

Management of recurrent LGSOC requires a multifaceted approach. Secondary cytoreduction, chemotherapy (often pegylated liposomal doxorubicin), hormonal therapies, and targeted agents may be considered. Bevacizumab, an anti-angiogenic agent, has shown promise in combination with chemotherapy. Clinical trials are ongoing to evaluate novel targeted therapies for recurrent LGSOC.

Hope and the Future of LGSOC Treatment

Low-grade serous carcinoma presents unique challenges due to its rarity and relative chemo-resistance. However, surgery remains a critical component of treatment, both in the initial stages and for recurrence. The integration of hormonal therapy and targeted agents offers new avenues for improving patient outcomes.

Ongoing research and clinical trials are crucial for developing more effective treatments for LGSOC. Investigating targeted therapies that address specific mutations in the KRAS/BRAF/MAPK and PI3K/AKT/mTOR pathways holds significant promise. Continued efforts to understand the molecular underpinnings of LGSOC will pave the way for personalized treatment strategies.

Living with LGSOC requires a collaborative approach between patients, families, and healthcare providers. Accessing support networks, participating in clinical trials, and staying informed about the latest research are essential. While LGSOC presents challenges, ongoing advances offer hope for improved outcomes and enhanced quality of life.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1055/a-0717-5411, Alternate LINK

Title: Low-Grade Serous Ovarian Carcinoma

Subject: Maternity and Midwifery

Journal: Geburtshilfe und Frauenheilkunde

Publisher: Georg Thieme Verlag KG

Authors: Enzo Ricciardi, Thaïs Baert, Beyhan Ataseven, Florian Heitz, Sonia Prader, Mareike Bommert, Stephanie Schneider, Andreas Du Bois, Philipp Harter

Published: 2018-10-01

Everything You Need To Know

What exactly is low-grade serous ovarian carcinoma (LGSOC)?

Low-grade serous ovarian carcinoma (LGSOC) is a distinct and rare subtype of ovarian cancer. Unlike the more common high-grade serous ovarian carcinoma (HGSOC), LGSOC accounts for only 5-10% of serous ovarian carcinomas. It's characterized by unique genetic and clinical features, requiring specialized treatment strategies. The World Health Organization classifies ovarian cancers into epithelial, non-epithelial, and metastatic types, with LGSOC falling under the epithelial serous category.

How is low-grade serous ovarian carcinoma (LGSOC) typically diagnosed?

The diagnostic process for low-grade serous ovarian carcinoma (LGSOC) involves clinical evaluation, imaging, and histological assessment. Patients often experience symptoms like abdominal or pelvic pain, bloating, or bowel dysfunction, similar to other ovarian cancers. A pelvic exam, CA125 blood test, and imaging studies such as ultrasound or CT scans are typically used. Histological assessment is crucial for confirmation, often distinguishing LGSOC from other ovarian cancer subtypes. This comprehensive approach ensures accurate diagnosis and guides treatment decisions.

What are the main treatment options for low-grade serous ovarian carcinoma (LGSOC)?

The primary treatments for low-grade serous ovarian carcinoma (LGSOC) include surgery, chemotherapy, hormonal therapy, and targeted therapies. Surgery aims for complete resection, and microscopic residual disease post-surgery correlates with improved survival. Chemotherapy, often with carboplatin and paclitaxel, is used, although LGSOC is less chemo-sensitive than HGSOC. Hormonal therapy, based on the frequent expression of estrogen and progesterone receptors, is a viable option. Targeted agents, particularly MEK inhibitors, are being investigated due to the prevalence of KRAS/BRAF/MAPK pathway mutations in LGSOC.

What is the relationship between serous borderline tumors (sBOT) and low-grade serous ovarian carcinoma (LGSOC)?

A significant link exists between serous borderline tumors (sBOT) and low-grade serous ovarian carcinoma (LGSOC), with around 60% of LGSOC cases having a history of sBOT. Gene expression profiling supports the theory that sBOT can transform into LGSOC. This relationship is crucial because it suggests a potential developmental pathway. Current classifications recognize sBOT with invasive implants as low-grade carcinomas, indicating a continuum. This understanding influences management strategies, emphasizing the importance of early detection and intervention.

How is recurrent low-grade serous ovarian carcinoma (LGSOC) managed?

Managing recurrent low-grade serous ovarian carcinoma (LGSOC) requires a multifaceted approach, including secondary cytoreduction, chemotherapy, hormonal therapies, and targeted agents. Pegylated liposomal doxorubicin is a commonly used chemotherapy agent in this setting. Hormonal therapies and targeted agents, such as MEK inhibitors, are also considered. Bevacizumab, an anti-angiogenic agent, can be used in combination with chemotherapy. Clinical trials are vital for evaluating new targeted therapies, reflecting ongoing efforts to improve outcomes for patients with recurrent LGSOC.