MOC Frequently Asked Questions

A diagnosis of cancer is never easy to hear. This is especially true when you learn you have a rare type, such as mucinous ovarian cancer (MOC).
Dr. Jennifer Mueller, a surgeon at Memorial Sloan Kettering Cancer Center in New York and an Coalition Advisory Committee member, answers the mostly commonly asked questions about MOC.
Q: What is so different about
mucinous ovarian cancer?
A: A primary mucinous ovarian cancer—MOC—is an uncommon type of ovarian cancer and accounts for less than 3% of the so-called ‘epithelial’ ovarian cancers.
It is very important to mention that ‘epithelial’ ovarian cancers include many different cell types, not just mucinous. So, it can be challenging to try to do research about MOC on your own, because most of the resources you come across will give information that is not specifically related to mucinous ovarian cancer. That’s why it is so important to have an expert health care team unpack your questions and make sure you have the facts.
Over two-thirds of women with MOC are diagnosed at an early stage (stage 1). This means the cancer is limited to just the ovary and has not spread to any other organ in the body. Women with MOC have an overall better prognosis than women with the more common ‘high-grade serous’ ovarian cancer type. We think this is because more women with MOC are diagnosed at an early stage.
About one-third of women with MOC are diagnosed with more advanced stages of disease. This means the cancer has spread beyond the ovary to other parts of the body. Advanced stage MOC is harder to treat, partly because it does not respond as well to chemotherapy drugs.
For this reason, oncologists often take an aggressive approach in treating advanced stage disease, using a combination of surgery to remove all the visible cancer, and chemotherapy, to kill cancer cells that the surgeon may not be able to see.
Q: Is there more than one type
of MOC?
A: Most MOCs actually aren’t primary ovarian cancers. The more common situation is that a mucinous cancer, found in a woman’s ovary, started in another place in her body. Most of the time these cancers come from the gastrointestinal tract, and less commonly from the pancreas, cervix or breasts.
In this situation the cancer is not primary to the ovary—meaning that it didn’t start there. Instead, it is called an ovary metastasis--a cancer that started somewhere else and spread to the ovary. Sometimes pathologists can tell whether a mucinous ovarian cancer is primary or metastatic based on the appearance of the cancer cells under the microscope.
Doctors use imaging (usually a CAT scan), the pathology report, and tumor markers that can be measured in the blood (CA-125, CEA and CA19-9) to help determine whether a cancer is primary or metastatic. It is very important to have a thorough evaluation looking for cancer in other areas of the body.
These tests can be done before or after surgery and include colonoscopy and upper endoscopy to examine the lining of the digestive system, mammogram to examine the breasts, a cervical pap smear, and physical exam that includes a pelvic exam.
Q: Are warning signs    
for MOC different than for other types of ovarian
A: The most common signs to look out for are bloating, pelvic or abdominal (belly) pain, trouble eating or feeling full too quickly, and urinary problems including increased frequency or urge to urinate. If any of these problems do not go away on their own and persist over several weeks, a woman should contact her doctor. These warning signs are not specific to ovarian cancer. Other conditions can cause these symptoms, but it is always safer to get checked out.
The most common warning sign is pelvic pain or discomfort. This is because the ovary affected by cancer often enlarges—to 10 cm (5 inches) or even more—putting pressure on other organs in the belly. Part of the doctor’s evaluation will usually lead to an imaging test like an ultrasound, MRI or a CAT scan to look for the cause of the problem.
Q: What questions should I ask my doctor if I’m newly diagnosed?
A: First of all, it helps to bring a friend or family member with you when you go to your medical visits. Or you can have your friend or family member participate on the phone. It helps to have another person there to ask questions, to take notes and to make sure you feel supported during your appointments.
Bring a list of all your questions to the first visit. After the first visit, make a list of any new questions that come up. Each woman and her circle of family or friends will have unique questions and concerns, so it is important to spend some time thinking this through.
There are several good online resources that offer basic but thorough lists of questions. These are great places to start. You can look at a basic list and then add questions of your own. Below are a few helpful websites.

Q: How do you know if
you are receiving the
right treatment when this cancer is so rare?
A: If you are diagnosed with MOC, it is important to seek out a gynecologic oncologist. These are specialists who manage cancers that start in the reproductive organs. They can deliver high-quality care and treatment because they are experts in all ovarian cancers.
It is also important to consider getting a second opinion to make sure you are comfortable and confident with your treatment plan. This is true for anyone facing a cancer diagnosis. It is especially helpful if you’re dealing with an uncommon type of cancer.
Q: Does MOC develop at a younger age than other ovarian cancers?
A: When compared with the most common ovarian cancer, ‘high-grade serous’ type, women with primary MOC are diagnosed at a younger age, usually in their early 50s. About 1 in 4 women with MOC are younger than 45.

Q: If my doctor tells me I have no evidence of disease after treatment, what should I be looking for moving forward?
A: First of all, this is wonderful news. ‘No evidence of disease’ is a cause for celebration. It is often a moment of relief and joy. But, like many women, you may also be worried about whether the cancer will come back—and if it does come back, how will you know?
The most important thing you can do is to have regular check-ups with your oncologist. These are called ‘surveillance’ visits. Surveillance visits are frequent at first (every 2-4 months for the first 3 years), because the risk of your cancer coming back is highest in the first 3 years.
So, your oncology healthcare team will want to keep a close eye on you during this time. Surveillance visits are a chance for them to meet with you and ask specific questions to detect any concerning signs (similar to the warning signs we reviewed above). They will also perform a physical exam which includes a pelvic exam.
You should always reach out to your healthcare team in between these appointments if something new develops that you think should be evaluated (abdominal pain, vaginal bleeding, nausea, vomiting, urinary problems, or any other problem).
Early on, your oncology team may order imaging tests like a CAT scan, or repeat a tumor marker testing (if you had an elevated tumor marker test at the time of your diagnosis). The frequency of routine imaging tests like a CAT scan can vary. These are usually done if you have a persistent symptom that’s bothering you, or if your doctor finds anything of concern during your physical exam.
As long as you continue to do well, surveillance visits will become less frequent over time.

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