Low-Grade Serous Ovarian Cancer (LGSOC)
What is LGSOC?
Low-grade serous ovarian cancer (also known as LGSOC) is a rare and serious ovarian cancer. It is distinct and different from the more common high-grade serous ovarian cancer (also known as HGSOC). LGSOC is likely to come back after initial treatment.
Low-grade serous ovarian cancer starts in the thin layer of tissue around the ovaries (also known as the epithelium) and can grow persistently.
Low-grade means that the cancer cells look a lot like normal cells.
Serous means that the cancer started in the serous membrane, which is part of the epithelium.
LGSOC affects younger people
LGSOC affects people at a broad range of ages, with large numbers between 20-30 years old and 50-60 years old. The average age at diagnosis for LGSOC is 43-48 years.
LGSOC is a rare cancer
About 5%
of all serous ovarian cancers are LGSOC
Nearly 2,000
new cases are diagnosed in the US each year
LGSOC symptoms
The symptoms of LGSOC are SERIOUS*
Stomach bloating
Eating less because you feel full
Repeated changes to bowel movements
Intense back and pelvic pain
Ongoing for up to 2 weeks
Urgent need to urinate
Stomach pain
*
This list is not exhaustive, as these are not all of the symptoms of LGSOC. Discuss any/all symptoms that you feel may be related to LGSOC with your doctor.
Diagnosing LGSOC
Because the LGSOC symptoms are similar to other diseases, like irritable bowel syndrome (IBS), it can be difficult to diagnose. It can take as long as 3 years to get an accurate LGSOC diagnosis.
- Up to 90% of patients with LGSOC are diagnosed at an advanced stage
- LGSOC is confirmed through a biopsy done by a pathologist, who may also perform what’s called germline and somatic testing to help your doctor guide treatment decisions
- If there has been no specific diagnosis for your type of ovarian cancer, consider getting a second opinion with a gynecologic oncologist with LGSOC experience
“Getting a second opinion is really important, especially for LGSOC, because it’s such a rare condition.”
–Kat, person living with LGSOC
Distinguishing LGSOC from HGSOC
LGSOC and HGSOC are two distinct and different cancers.
LGSOC
HGSOC
Uncommon
About 5% of serous ovarian cancers
Very common
About 95% of serous ovarian cancers
Affects younger people
The average age at diagnosis is 43-48 years, but has been diagnosed in people as young as 14 years old
Affects older people
Most people are over 60 years old when diagnosed
Normal-looking cells
Cells look like non-cancer cells
Abnormal-looking cells
Cells look unstructured or underdeveloped
Grows slowly
Cancerous cells grow slowly but persistently
Grows quickly
Cancerous cells grow quickly
Progresses slowly
Can start as benign (non-cancerous) before becoming cancerous and spreading
Progresses rapidly
Spreads quickly outside of ovaries
Less sensitive to chemotherapy
Other treatments may be required
Usually responds to chemotherapy
Responsive to chemotherapy, which can slow/stop the spread of cancer
LGSOC quiz
Low-grade serous ovarian cancer can be misunderstood, even by the healthcare community
The more you know, the better advocate you can be for your own health.
References
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