Computed Tomography and Magnetic Resonance Imaging Findings in Cases of Dermoid Cyst Coexisting with Surface Epithelial Tumors in the Same Ovary

Collision Tumor of the Ovary: Adult Granulosa Cell Tumor and Mesonephric-like Adenocarcinoma

Collision tumors of the ovaries are rare, with only a few reports in the literature. Adult granulosa cell tumors are a relatively common primary tumor component of previously reported collision tumors. The combination of serous and mucinous tumors with adult granulosa cell tumors has been reported in several cases. On the other hand, mesonephric-like adenocarcinomas are rare neoplasms that commonly arise in the uterine corpus and ovaries. In this report, we present the case of a collision tumor composed of an adult granulosa cell tumor and mesonephric-like adenocarcinoma of the ovary in a 63-year-old woman. The initial magnetic resonance imaging findings showed a cystic mass with an internal hemorrhage, which suggested an adult granulosa cell tumor, and a solid mass with different enhancements. Microscopically, the tumor had two distinct components: An adult granulosa cell tumor and a mesonephric-like adenocarcinoma. Recognizing collision tumors consisting of slow-growing and aggressive tumors may prove beneficial in future diagnostic and treatment strategies.

Diagnostic roles of PAX8 immunohistochemistry in ovarian tumors

OBJECTIVE

This study aimed to elucidate the diagnostic roles of PAX8 immunohistochemistry in various ovarian tumors.

METHODS

We searched through the PubMed database and selected the eligible studies to perform the meta-analysis. The PAX8 immunohistochemical expression rates of various ovarian tumors, including primary and metastatic carcinomas, were analyzed. In addition, the subgroup analysis based on tumor behaviors was performed.

RESULTS

The PAX8 expression rates were 0.056 (95% confidence interval [CI] 0.008-0.307), 0.400 (95% CI 0.228-0.600), 0.741 (95% CI 0.578-0.857), and 0.738 (95% CI 0.666-0.799) in normal ovary and benign, borderline, and malignant ovarian tumors, respectively. The PAX8 expression rates of serous and transitional cell carcinomas were 0.937 (95% CI 0.882-0.967) and 0.918 (95% CI 0.841-0.959). In addition, the PAX8 expression rate of mucinous carcinomas was 0.393 (95% CI 0.285-0.512). However, metastatic carcinomas showed a significantly lower PAX8 expression rate than primary ovarian cancers (P < 0.001 in the meta-regression test). In cytologic specimens, PAX8 expression rates of serous and endometrioid carcinomas were 0.905 (95% CI 0.832-0.948) and 0.714 (95% CI 0.327-0.928), respectively.

CONCLUSION

PAX8 expression rate was significantly higher in serous ovarian tumors than in mucinous ovarian tumors. In addition, PAX8 expression rates were significantly higher in primary ovarian cancers than in metastatic carcinomas.

Ovarian Collision Tumor, Massive Mucinous Cystadenoma, and Benign Mature Cystic Teratoma

Collision tumors are rare neoplasms defined by the presence of two distant tumors in the same organ without any histological intermixing. Ovarian tumors are often asymptomatic during the early stages and become symptomatic when increased in size causing vague abdominal pain, abdominal distention, vomiting, and frequent urination. We report here a case of a 28-year-old female who presented with a history of worsening abdominal pain and distension. An abdominopelvic ultrasound scan showed a huge complex mass occupying the pelvic area with non-visualization of the left ovary suggesting an ovarian origin; further characterization by cross-sectional imaging by both CT and MRI were performed confirming a left ovarian complex mass containing multiseptated cystic and fat component at the same time along with massive ascites. After surgical resection of the mass, histopathology revealed mucinous cystadenoma coexisting with cystic teratoma.

A rare combination of Dermoid cyst and Cystadenoma: Are collision tumors in the ovary a real entity?

Collision tumors have been reported in various organs like the gastrointestinal tract, lung, skin, adrenals, central nervous system, lymph nodes, uterus, but are rarely seen in the ovary. Collision tumors are two histologically distinct neoplasms in the same organ without any intermixture between them. Here we present a case of a collision tumor of the ovary represented by a mucinous cystadenoma and teratoma. It is imperative for a surgical pathologist to correctly diagnose the collision tumor components and differentiate them from mixed tumors as it will dictate the appropriate treatment based on the individual biological aggressiveness of each component.

Pseudomyxoma peritonei of a mature ovarian teratoma caused by mismatch repair deficiency in a patient with Lynch syndrome: a case report

BACKGROUND

Pseudomyxoma peritonei (PMP) is a rare disease with an estimated incidence of 1-2 cases per million individuals per year. PMP is characterized by the accumulation of abundant mucinous or gelatinous fluid derived from disseminated tumorous cells. Most of the tumorous cells are originated from rupture of appendiceal neoplasms, but some are from the metastasis of cancer of the colon, ovary, fallopian tube, urachus, colorectum, gallbladder, stomach, pancreas, lung and breast. Although frequent mutations in KRAS and/or GNAS genes have been reported, precise molecular mechanism underlying PMP remains to be elucidated. It is of note that mucinous tumour is one of the frequent histological features of colorectal cancer (CRC) in Lynch syndrome (LS), an autosomal dominantly inherited disease caused by a germline mutation of the DNA mismatch repair (MMR) genes including human mutL homolog 1 (MLH1), human mutS homolog 2 (MSH2), human mutS homolog 6 (MSH6), and postmeiotic segregation increased 2 (PMS2). Therefore, typical LS-associated tumours show mismatch repair instability. Although LS patients are most strongly predisposed to CRC, PMPs from mucinous CRC have not been reported in LS patients.

CASE PRESENTATION

In this report, we report a case of PMP originating from an ovarian teratoma in a LS patient. The patient had surgical treatment of PMP arising from an ovarian teratoma at the age of 38 years, and later developed a transverse colon cancer at the age of 40. The patient's family history fulfilled the Amsterdam criteria, and genetic analysis of the peripheral leukocytes identified a germ line mutation in the MLH1 gene (MLH1 c.1546dupC p.Q516PfsX3). Interestingly, immunohistochemical staining showed that the expression of MLH1 was lost in the colon cancer as well as the ovarian teratoma. Consistent with the loss of MLH1 expression, both tumours showed high microsatellite instability (MSI-H).

CONCLUSION

This case suggested that LS patients may develop various types of tumours including ovarian PMP, and that mismatch repair deficiency may play a role in the development of PMP derived from, at least, a part of ovarian teratomas.

Mucinous Cystadenocarcinoma Co-Existing with Mature Cystic Teratoma : A Rare Case Report

Co-existence of mucinous cystadenocarcinoma with mature cystic teratoma in the same ovary is very rare. We report a case in a 48-year-old female who presented with left abdominal mass. CT scan revealed a heterogeneous enhancing left ovarian mass lesion. Clinical diagnosis of complex ovarian cyst was made, later underwent laparotomy and histologically diagnosed as mucinous cystadenocarcinoma (grade 2) co-existing with benign cystic teratoma, stage Ia (FIGO) of the left ovary. Six months after surgery, the patient is doing well without any recurrence or metastasis. Hence, histopathological examination plays a significant role in accurate diagnosis and management of the patient. So, we should be aware of these rare co-existent tumours and meticulous dissection should be done to look for any synchronous tumours or malignant areas; since management and prognosis will vary significantly depending upon the microscopic type and stage.

Differentiation of ovarian cancers from borderline ovarian tumors on the basis of evaluation of tumor vascularity in multi-row detector computed tomography--comparison with histopathology

OBJECTIVE

The aim of this study was to evaluate the feasibility of multi-detector row computed tomography (MDCT) in the differentiation between borderline ovarian tumors and ovarian cancer on the basis of tumor morphology and specific features of tumor vascularity in correlation with the results at pathology.

METHODS

A triphasic MDCT protocol was used for the analysis of tumor vascularity. The following features were taken into account: (1) The number of vessels in papillary projections, solid-tissue component, and septa (2 vs >2), (2) serpentine and chaotic configuration of vessels, (3) presence of microaneurysms, and (4) presence of arteriovenous microfistulas. Masses with at least 3 of 4 features were considered ovarian cancer (group A) and masses with 2 features or less as borderline tumor (group B). Radiological findings were compared with results of postoperative pathology.

RESULTS

Pathologic vessels were found in all 56 patients. Thirty-two patients were included in group A and 24 in group B. The results of pathology were as follows: in group A: 31 malignant tumors, including 31 ovarian carcinomas and 1 benign cystadenoma; in group B: 22 borderline ovarian tumors, 1 benign cystadenoma, and 1 ovarian cancer.

CONCLUSIONS

Morphological evaluation of tumor vascularity in MDCT seems to be an efficient method of differentiating between borderline ovarian tumors and ovarian carcinomas. Because of a small number of cases in the current study, a further research seems justified to confirm our results. The presented MDCT-angiographic criteria showed high sensitivity (97%) and specificity (96%) in differentiation of borderline ovarian tumors and ovarian cancers as compared with pathology. The presented CT-angiographic criteria of malignancy showed an excellent interobserver agreement.

Ovarian mucinous cystadenoma coexisting with benign Brenner tumor: MR imaging findings

PURPOSE

The purpose of this study was to describe the MR imaging findings of ovarian mucinous cystadenomas coexisting with benign Brenner tumors.

MATERIALS AND METHODS

MR images with a 1.5-T unit obtained in five consecutive patients (age range, 51-72 years; mean age, 61 years) with surgically confirmed ovarian mucinous cystadenomas coexisting with benign Brenner tumors were retrospectively reviewed for the presence, configuration, and signal intensity of cystic and solid components of the lesions.

RESULTS

Tumors ranged in size from 7.5 to 22.1 cm (mean, 13.5 cm). In four patients (80%), the size of mucinous cystadenoma (range 6.4-22.1 cm; mean, 12.5 cm) was larger than that of Brenner tumor (range 0.2-9.1 cm; mean, 2.8 cm). All patients (100%) had cystic, and three (60%) had solid components. Four patients (80%) showed multilocular cystic, and one (20%) showed unilocular cystic appearance. MR imaging findings were classified into three patterns: (1) a bulky solid mass adjacent to the cystic component, (2) a mural nodule at the periphery of the cystic component, and (3) a cystic component without a detectable solid component. All four multilocular cystic areas exhibited "stained glass" appearances on both T1- and T2-weighted images, and all three solid areas showed homogeneous hypointensity on T2-weighted images.

CONCLUSION

Mucinous cystadenomas were often larger than the coexisting benign Brenner tumors. Mucinous cystadenomas coexisting with benign Brenner tumors should be considered when multilocular or unilocular cystic components are accompanied by homogeneously hypointense solid components on T2-weighted images.

Ovarian Mucinous Tumors Associated With Mature Cystic Teratomas

Most primary ovarian mucinous tumors are of surface epithelial-stromal origin and exhibit diffuse expression of cytokeratin 7 (CK7) combined with variable expression of cytokeratin 20 (CK20); this immunoprofile distinguishes them from most lower gastrointestinal tract tumors secondarily involving the ovaries. The uncommon ovarian mucinous tumors of germ cell (teratomatous) origin have not been extensively evaluated to determine the utility of these markers and other markers of intestinal differentiation for distinguishing these tumors from metastatic gastrointestinal tract mucinous tumors. Immunohistochemical expression of CK7, CK20, CDX2, and villin was assessed in 44 ovarian mucinous tumors associated with a mature cystic teratoma. All cases lacked evidence of a nonovarian primary mucinous tumor. All mucinous tumors were unilateral; 6 cases had bilateral teratomas. All tumors displayed gastrointestinal-type mucinous differentiation, with epithelium that was commonly goblet cell-rich or hypermucinous; 21 were associated with pseudomyxoma ovarii and 3 of these had pseudomyxoma peritonei. Tumor architecture ranged from purely cystadenomatous (n=24), to proliferative (n=13), to carcinomatous (n=6); some tumors had admixtures of these patterns. One tumor had a goblet cell carcinoidlike pattern with pseudomyxoma ovarii. Three carcinomas had a signet ring cell component. Cystadenomatous tumors without pseudomyxoma ovarii (n=15) exhibited all possible CK7/CK20 coordinate expression profiles with nearly equal frequency. All proliferative tumors without pseudomyxoma ovarii (n=8) expressed CK7, most often in combination with CK20 expression. All cystadenomatous and proliferative tumors with pseudomyxoma ovarii (n=9 and n=5) were CK7-/CK20+. All carcinomatous tumors had pseudomyxoma ovarii; 3 were CK7-/CK20+, 2 were CK7+/CK20+, and 1 was CK7+/CK20-. The presence of pseudomyxoma ovarii was significantly associated with a CK7-/CK20+ profile (86% with pseudomyxoma ovarii vs. 13% without, P<0.0001), CDX2 positivity (79% vs. 0%, P<0.0001), and villin positivity (57% vs. 5%, P=0.0009). A subset of mucinous tumors associated with mature cystic teratomas exhibiting morphologic and immunohistochemical features of lower intestinal tract-type mucinous tumors may be teratomatous in origin. In practice, the more common diagnosis of secondary involvement by a lower intestinal tract mucinous tumor should be addressed in the pathology report and in subsequent clinical evaluation; interpretation as a true primary ovarian mucinous tumor of teratomatous origin can be considered as an alternative diagnosis when evaluation and follow-up fail to identify a nonovarian source of the mucinous tumor. Those tumors having CK7 expression with or without CK20 expression may be derived from upper gastrointestinal tract-type or sinonasal-type teratomatous elements but could be independent tumors of surface epithelial-stromal origin.

Calcifications in mucinous and serous cystic ovarian tumors

Mucinous cystic ovarian tumors sometimes contain calcifications, but the frequency and significance of such calcifications in diagnostic radiology are not well understood. We therefore retrospectively investigated the radiological and histopathological evidence of calcifications in 44 cases of ovarian mucinous cystic tumors (22 benign, 13 borderline, and 9 malignant) and 21 cases of ovarian serous cystic tumors (6 benign and 15 malignant) in which a non-contrast CT scan was performed. The shape and distribution of the calcifications in the mass lesion were assessed both radiologically and histopathologically. Calcifications were noted in 34.1% of mucinous cystic tumors on CT scans and 56.8% in histopathological studies, and they were found in two locations, intramural and intra-cystic, according to the histopathological findings. Intramural calcifications were frequent in benign tumors, and intra-cystic calcifications were frequent in proliferating tumors. Calcifications (psammoma bodies) were noted in 4.7% of serous cystic tumors on CT scans and 14.3% in histopathological studies. CT was not sufficiently sensitive in the detection of intra-cystic calcification in mucinous tumors and psammoma bodies in serous tumors. However, the presence of intramural calcifications may be a good indicator of mucinous tumors. Understanding the frequency and morphology of the calcifications in these neoplasms is one of the keys to making a correct diagnosis.