Ovarian Masses Part 2
Review of ovarian masses for radiology board exams. Download the free study guide on this topic by clicking here.
Show Notes/Study Guide:
What are some imaging features of an ovarian cyst that raise concern for malignancy?
Thick or numerous internal septations, papillary projections, solid components within the cyst and larger size of lesion. Complex cystic and solid adnexal masses are concerning whether unilateral or bilateral including masses with thick septations, over something like 3 mm in thickness, as well as cystic lesions with solid nodules, mural nodularity or irregularity, papillary projections, and predominantly solid masses with internal necrosis.
What ovarian findings can be seen with a molar pregnancy?
A molar pregnancy often presents with a snowstorm and/or cystic appearance of the uterus and may have associated findings of ovarian hyperstimulation with theca lutein cysts or ovarian metastases. Other things to consider for the Core Exam are that if they give you a history of hemoptysis with molar pregnancy you should consider this a sign of possible pulmonary metastatic disease. With molar pregnancy beta-HCG will be elevated.
What is Meigs syndrome?
Meigs syndrome consists of the triad of pleural effusion, ascites, and a benign ovarian tumor which is commonly a fibroma. Fibromas are benign tumors that are most common in middle aged females. Imaging of a fibroma includes an ovarian mass that is hypointense on both T1- and T2-weighted images, sometimes with a peripheral band of T2 hypointensity. On ultrasound these will appear solid and hypoechoic. Interestingly, the ascites and pleural effusions typically resolve with resection of the benign ovarian tumor.
If you are shown a solid ovarian mass in a young child, what should you consider first on the Core Exam?
Sex chord stromal tumor of the ovary
If you are shown a solid ovarian mass in an adolescent, what should you consider first on the Core Exam?
Granulosa cell tumor. Note that this is an estrogen secreting tumor and as such can be associated with endometrial thickening as well.
What other ovarian malignancy commonly presents with an ovarian mass and associated endometrial thickening?
An endometrioid cancer of the ovary also commonly presents as an ovarian mass (bilateral in 20% or more of cases) with endometrial thickening which may represent endometrial hyperplasia or endometrial carcinoma. This tumor is also commonly associated with endometriosis.
True or false: An endometrioid cancer of the ovary can arise from within an endometrioma?
True, although a rare occurrence.
What is the most common ovarian malignancy?
Serous ovarian tumors are the most common ovarian malignancy. A serous ovarian cystadenoma is the more benign version, and a serous ovarian cystadenocarcinoma is the malignant variety. These can be very large, predominantly cystic tumors, with only a few abnormal septations. Serous tumors in older females are more likely to be malignant. Bilateral serous tumors are also more likely to be malignant. Ascites with an associated ovarian cystic neoplasm essentially confirms metastatic disease and over half have peritoneal metastases at time of diagnosis.
What is a classic clinical presentation of a juvenile granulosa cell tumor of the ovary?
Precocious puberty due to tumoral estrogen secretion. These most commonly present in young females, mean age of around 12 years. Remember associations with Ollier disease (multiple enchondromas) and Maffucci syndrome (multiple enchondromas and hemangiomas/venous malformations).
What are key features of a Brenner tumor of the ovary?
Brenner tumors are rare ovarian tumors that can also occur in the testis in males. These are most common in middle-aged females. 1 in 3 cases will have another ovarian neoplasm (same or other ovary). These are usually small in size, look like mixed multicystic and solid masses, most commonly with some calcifications, appear hypointense on T2-weighted MRI, and have a tendency not to metastasize.
What is a Krukenberg tumor of the ovary?
This is an ovarian metastasis with a characteristic “signet ring” morphology, most commonly from colon, gastric, breast and lung malignancies with gastric most common. These are mucin secreting tumors. These account for half of ovarian metastases, most common in young to middle aged females. Presenting features include dyspareunia and irregular uterine bleeding. These are commonly bilateral. If you see this on pathology you then need systemic imaging to look for a potential primary with consideration as well for colonoscopy and upper endoscopy.
What is the most common ovarian neoplasm?
An ovarian serous cystadenoma. These are most common in middle aged females. On imaging these are classically large or somewhat large often unilocular cystic lesions without wall thickening/irregularity, solid components, or papillary projections. A few thin septations may be present. The beak sign can help confirm ovarian etiology. If no beak sign is present, this could be a paraovarian cyst. Due to potential risk of malignant degeneration these are usually surgically excised.
What is the most common malignant ovarian tumor?
A serous cystadenocarcinoma comprises up to 75% of malignant epithelial ovarian tumors. This is the malignant version of an ovarian cystadenoma. Imaging features are that of a cystic ovarian mass with at least one solid component that would typically enhance and show restricted diffusion on MRI. Papillary projections may also be seen as well as wall irregularity. These may be bilateral. If ascites is present, assume metastatic disease and evaluate on imaging for peritoneal nodularity and masses.
True or false: Ovarian serous tumors are typically larger than ovarian mucinous tumors?
False. Ovarian mucinous tumors are typically larger than ovarian serous tumors.
True or false: Ovarian mucinous tumors are more likely to be bilateral compared to ovarian serous tumors?
False. Ovarian serous tumors are more likely to be bilateral in comparison to ovarian mucinous tumors.
True or false: Peritoneal carcinomatosis is more common with ovarian serous tumors compared to ovarian mucinous tumors?
True. Serous tumors more commonly have associated peritoneal carcinomatosis.
True or false: The median survival for an ovarian mucinous cystadenocarcinoma is worse compared to an ovarian serous cystadenocarcinoma?
True. The median survival is worse by about 2-3 years for advanced ovarian mucinous cystadenocarcinoma compared to an ovarian serous cystadenocarcinoma.
True or false: Ovarian mucinous tumors are more likely to be multilocular compared to ovarian serous tumors?
True. Ovarian mucinous tumors commonly are multilocular with more numerous small cystic components.
What is the “stained glass appearance” of an ovarian mucinous tumor?
Different signal intensities within the cystic spaces on MRI, resulting from different concentrations of mucin within the cystic fluid, results in a mixed signal intensity imaging appearance termed the “stained glass appearance”.
What are key imaging features suggesting an ovarian mucinous cystadenocarcinoma?
Thickened septations, mural thickening and irregularity, solid enhancing nodular components, and a very large adnexal mass with possible “stained glass appearance” are some of the classic imaging features of an ovarian mucinous cystadenocarcinoma. Note that these may be early stage, even when very large.
True or false: an ovarian clear cell carcinoma develops in patients with endometriosis in one-fourth of cases?
True. Also remember that ovarian clear cell carcinomas are very frequently malignant.
What is an ovarian collision tumor?
When two histologically unique tumors are present within an ovary, with no mixing at the tumoral interfaces, this is termed an ovarian collision tumor. These are rare, and most commonly consist of an ovarian cystadenoma/cystadenocarcinoma and an ovarian teratoma.
What is pseudomyxoma peritonei?
Mucinous ascites that occurs after rupture of a mucinous neoplasm is termed pseudomyxoma peritonei. The most common cause of this is a ruptured appendiceal mucinous tumor, but other mucinous tumors in the abdomen and pelvis can also do this. Ovarian mucinous tumors can also cause pseudomyxoma peritonei if they rupture. This can occur from rupture of benign mucinous tumors, not only the malignant varieties. On imaging, look for loculated fluid collections throughout the peritoneal cavity, scalloping of abdominal organs most commonly the liver, omental caking, and a primary mucinous tumor, most commonly involving the appendix. Bowel involvement with recurrent bowel obstructions is a late manifestation of disease. This can be fatal, and treatment requires surgical debulking, IV or intraperitoneal chemotherapy.
Ovarian tumors more commonly cause peritoneal carcinomatosis, as well as GI cancers to include gastric, esophageal, and colon cancers, as well as other cancers that include melanoma, breast, and lung cancer. Imaging often does not depict the full extent of disease, so disease is typically worse on surgery with direct inspection, compared to CT or MRI. Omental caking is part of peritoneal carcinomatosis and occurs when the omentum becomes invaded and thickened with tumor cells. Ascites typically results as well. If you see calcifications, consider first an ovarian cystadenocarcinoma as the primary tumor.
