A mucinous cystadenoma is a type of tumor which is typically benign, or non-cancerous, and which may develop in the ovaries, pancreas or, rarely, the appendix. In the ovary, mucinous cystadenomas are the most frequently occurring large tumors, while in the pancreas, they are not common, but there is a risk that they could eventually change to become malignant, or cancerous. Mucinous means mucus-producing, a cyst is a space full of fluid, and an adenoma is a tumor arising from glandular tissue. So, these types of tumors consist of a collection of spaces, full of mucus-like material, which have developed from glandular cells. A mucinous cystadenoma may be treated by surgical removal in order to prevent future complications.
When a mucinous cystadenoma develops in the form of an ovarian tumor, it is more frequently found in women between the ages of 30 and 50. Unlike the other tumor type described in the cystadenoma grouping system, which is known as a serous cystadenoma, a mucinous tumor is only thought to be malignant, or cancerous, in around 5 percent of cases. In contrast, almost a third of serous cystadenomas, which arise from serous glandular cells that produce a watery fluid, are thought to be malignant. Symptoms which may be associated with a large mucinous cystadenoma include aches and pains in the lower back or abdomen, an abdominal swelling which can be felt, and a need to empty the bladder more often. If a tumor twists or ruptures, the patient may experience more severe pain and require immediate surgery.
In the pancreas, mucinous cystadenomas are much more likely to occur in women, with only around 20 percent being found in men. There may be no symptoms until the tumor is large enough to press on surrounding tissues, when problems such as upper abdominal pain and jaundice may be experienced. A mucinous cystadenoma in the appendix is very rare, and it may be found during a routine scan, or it could occasionally cause symptoms resembling appendicitis, such as pain in the lower right abdomen. Sometimes, such a tumor in the appendix can rupture, causing a condition known as pseudomyxoma peritonei. In pseudomyxoma peritonei, tumor cells that have become malignant spread through the abdomen, producing mucus and causing problems such as abdominal swelling and pressure on organs.
Diagnosis of a mucinous cystadenoma generally involves imaging scans, using technology such as computerized tomography (CT) and ultrasound. Surgery to remove tumors may be carried out using conventional techniques or, in some cases, laparoscopic methods, where smaller incisions are required. The outlook for someone with a mucinous cystadenoma is usually positive because tumors are removed before they can cause complications due to increasing size, or malignant change.