Primary papillary serous carcinoma of the peritoneum: CT-pathologic correlation

CT review of ovarian fibrothecoma

Objective:

The aim of this study was to investigate the CT imaging characteristics of ovarian fibrothecoma which may aid in the differentiation from early stage epithelial tumours.

Methods:

Comparison of 36 patients (41 lesions) with pathologically proven ovarian fibrothecoma tumours and 36 (52 lesions) serous papillary carcinomas (SPCs) lesions. We noted their laterality, size, density, calcifications, Hounsfield units (HUs) and introduced a novel HU comparison technique with the psoas muscle or the uterus. Patients’ clinical findings such as ascites, pleural effusion, carbohydrate antigen-125 levels, and lymphadenopathy findings were also included.

Results:

Average age was 67.8 and 66 across the fibrothecoma and SPC cohort respectively. Fibrothecoma tumours had diameters ranging from 24 to 207 mm (Median: 94 mm). 80.6% of the fibrothecoma cohort had ascites which was comparable to the 72.2% in the SPC cohort. 70.7% of fibrothecoma tumour favour a purely to predominantly solid structural configuration (p < 0.001). The average HU value for the fibrothecoma solid component was 44 ± 11.7 contrasting the SPC HU value of 66.8 ± 15. The psoas:tumour mass ratio demonstrated a median of 0.7, whereas SPCs shows a median of 1.1 (p < 0.001).

Conclusion:

Suspicion of ovarian fibrothecoma should be considered through interrogation of their structural density configuration, low psoas to mass HU ratio and a presence of ascites.

Advances in knowledge:

CT imaging can be a useful tool in diagnosing fibrothecoma tumours and subsequently reducing oncogynaecological tertiary centre referrals, financial burden and patient operative morbidity and mortality.

Primary peritoneal serous carcinoma: a primer for radiologists

Primary peritoneal serous carcinoma (PPSC) is a rare primary peritoneal tumor characterized by a unique range of clinical features and imaging findings. Though it shares many clinical, histologic, and imaging features with serous ovarian carcinoma, it remains a distinct clinical entity. Although less common than its primary ovarian counterpart, PPSC is characterized by a prognosis that is often equally poor with presentations common in late stages of disease. Key imaging modalities used in the evaluation of PPSC include ultrasound, CT, MRI, and PET/CT. For radiologists, an understanding of the pertinent imaging findings, pathologic correlations, and clinical features of PPSC is essential for arriving at the correct diagnosis and guiding the subsequent appropriate management of this complex malignancy.

Peritoneal carcinomatosis: comparison of dynamic contrast-enhanced magnetic resonance imaging with surgical and histopathologic findings

OBJECTIVE

In patients with peritoneal carcinomatosis (PC) accurate preoperative assessment is essential to determine indication and surgical procedure to ensure optimal outcome. Purpose of our study was to assess the diagnostic accuracy (DA) of multiphasic dynamic contrast-enhanced MRI to determine the extent of PC in correlation with surgical and histopathological findings.

MATERIALS AND METHODS

14 Patients with proven PC were examined on a 1.5T system before peritonectomy and hyperthermic intraperitoneal chemotherapy. Patient preparation included oral application of 2000 mL mannitol solution and 40 mg butylscopolaminiumbromid i.v. Coronal contrast-enhanced multiphasic dynamic T1w 3D gre sequences (T1W DCE) (0.15 mmol Gd-chelate/kg bw) covering the whole abdomen were acquired (TR 2.9 ms, TE 1.1 ms, resolution 2.0 × 2.0 × 1.8 mm, FOV 400 × 400 mm). MRI was assessed by two radiologists and correlated with surgical exploration (SE) and histopathology for each segment based on the peritoneal cancer index proposed by Sugarbaker et al.

RESULTS

In total, 182 segments were evaluated. PC was found in 118/121 of 182 segments (reader 1/2) by MRI and in 131 segments by SE. In 4/7 segments MRI was false positive. False negative segments 17/17 in MRI did not result in irresectability. The positive predictive value for PC per segment of MRI was 97%/94%, the negative predictive value 73%/72%, the sensitivity 87%/87% and the specificity 92%/86%. The DA was 88%/87%.

CONCLUSION

T1W DCE is an accurate and clinical valuable tool for the preoperative assessment of peritoneal tumor spread.

Extraovarian primary peritoneal carcinoma: staging with 18F-FDG PET/CT

A 69-year-old woman who presented with left lower quadrant abdominal pain and elevated serum cancer antigen 125 (CA-125) levels was referred for an MRI and an (18)F-FDG PET/CT to evaluate a suspicious abdominal mass seen on ultrasound. PET/CT showed extensive, intensely FDG-avid, omental and pelvic peritoneal thickening with no suspicious ovarian or colon masses. Based on the PET/CT results, the patient had extensive debulking surgery and histopathological evaluation revealed an extraovarian primary peritoneal carcinoma (EOPPC). (18)F-FDG PET/CT may be useful in differentiating EOPPC from other types of peritoneal carcinomatosis, and in determining the extent of the disease to better guide surgical management and improve long term outcomes.

Primary peritoneal carcinoma: computed tomography and magnetic resonance findings

OBJECTIVE

To present computed tomography (CT) and magnetic resonance imaging (MRI) findings of primary peritoneal carcinoma (PPC) at initial presentation (IP) and recurrent disease (RD).

METHODS

We studied 15 consecutive female patients (age range, 47-83 years; mean, 66.2 years) with pathologically proven PPC who underwent CT and/or MRI between July 2000 and December 2005. Preoperative radiological evaluation and postoperative follow-up was done with CT and/or magnetic resonance studies. All CT and MRI studies were evaluated retrospectively, independently, and blindly by 2 radiologists for the imaging findings of PPC.

RESULTS

The imaging findings were as follows: ascites, 2 of 2 at IP, 9 of 10 at RD; peritoneal thickening and enhancement, 1 of 2 at IP, 9 of 10 at RD; peritoneal nodules or bulky mass lesions, 1 of 2 at IP, 8 of 10 at RD; lymph node involvement, 1 of 2 at IP, 3 of 10 at RD; and distant metastases, 1 of 10 at RD.

CONCLUSION

Ascites, peritoneal thickening and enhancement, and peritoneal nodules or bulky mass lesions were the most frequent findings of PPC. Recurrent disease revealed similar findings compared with the IP.

Neoplastic and nonneoplastic conditions of serosal membrane origin: CT findings

Computed tomography (CT) is an important imaging modality for diagnosis and follow-up of neoplastic or nonneoplastic conditions of the serosal membrane. The characteristic CT findings of malignant pleural mesothelioma include unilateral pleural effusion, thickening of the mediastinal pleura, and circumferential and nodular pleural thickening of greater than 1 cm. Malignant peritoneal mesothelioma manifests as a large mass or diffuse peritoneal thickening without a definable mass and is difficult to differentiate from peritoneal carcinomatosis or tuberculosis. The imaging features of primary serous papillary carcinoma of the peritoneum resemble those of peritoneal carcinomatosis; however, the ovary is usually of normal size. The possibility of desmoplastic small round cell tumor should be considered in children or young adults with multiple peritoneal masses and no identifiable primary malignancy. The CT findings of secondary tumors include a variable amount of fluid in the serosal cavity, thickening of the serosal lining (irregular and nodular), and serosal implants. Nonneoplastic conditions manifest as focal or diffuse thickening of the serosal membrane, a variable amount of fluid in the serosal cavity, and a soft-tissue mass at CT. Although the CT findings of some of the conditions overlap, knowledge of the typical findings is helpful in narrowing the differential diagnosis.

Serous Psammocarcinoma of the Ovary

Serous psammocarcinoma, a rare variant of ovarian serous carcinoma, is characterized histologically by the pervasive presence of psammoma bodies. In this case, computed tomography scans showed extensively calcified pelvic and peritoneal masses. The pelvic mass appeared sandy on enhanced T1-weighted magnetic resonance images. These imaging results suggest that the presence of abundant psammomatous calcifications in primary and disseminated lesions may be a radiological marker of ovarian psammocarcinoma.

CT Features of Serous Surface Papillary Carcinoma of the Ovary

OBJECTIVE

The purpose of this study was to determine the CT appearance of serous surface papillary carcinoma of the ovary.

MATERIALS AND METHODS

CT scans of 17 patients with histologically proven serous surface papillary carcinoma of the ovary were retrospectively reviewed. We evaluated the ovary size, omental or mesenteric involvement (none, mild, or severe), ascites (none, small, moderate, or large), and peritoneal thickening (none, smooth, or nodular). We also noted the presence of a cul-de-sac mass, lymphadenopathy, and calcification within the peritoneal mass. The preoperative serum level of cancer antigen (CA)-125 was assessed in all patients.

RESULTS

The diameter of ovaries was 3 cm or smaller in 14 patients (82%). All patients had omental or mesenteric involvement by the tumor (mild, n = 2; severe, n = 15) and ascites (small, n = 1; moderate, n = 3; large, n = 13). Peritoneal thickening (smooth, n = 5; nodular, n = 10) was noted in 15 patients (88%) and a cul-de-sac mass in 10 (59%). Lymphadenopathy was noted in five patients (29%) and calcification within the peritoneal mass in one (6%). Serum CA-125 level was elevated in all patients (168-63,300 U/mL).

CONCLUSION

Serous surface papillary carcinoma of the ovary should be suggested as a diagnosis in patients who have peritoneal carcinomatosis, relatively normal-sized ovaries, and a highly elevated serum CA-125 level.

Primary papillary serous carcinoma of the peritoneum: Four cases and review of computed tomography findings

Primary papillary serous carcinoma of the peritoneum is an uncommon primary malignancy of the peritoneum and is histologically indistinguishable from papillary serous carcinoma of the ovary. The diagnosis of primary peritoneal papillary serous carcinoma should be considered in the presence of peritoneal and omental masses in the absence of an ovarian mass. Although it has been extensively documented in the pathological and gynaecological oncology literature, the CT appearance of primary papillary serous carcinoma of the peritoneum has been reported in only 51 cases in five reports. We present four patients with CT findings of pathologically proven primary papillary serous carcinoma of the peritoneum. There were a total of 23 patients with a histopathologically proven diagnosis of primary papillary serous carcinoma of the peritoneum between 1980 and 2002 with CT imaging. However, only four of the 23 patients' CT films were retrieved for retrospective evaluation. The rest of the films were not available as either patients had misplaced the films or patients were deceased.

Staging ovarian cancer: role of imaging

Ovarian cancer is relatively common, and often presents at an advanced stage with widespread intraperitoneal metastases. The constellation of complex pelvic masses, ascites, omental cake, and other peritoneal implants is virtually diagnostic. All patients are potential surgical candidates, since suspected early stage disease is treated by a comprehensive staging laparotomy including total abdominal hysterectomy, bilateral salpingo-oophorectomy, and omentectomy. Operable advanced disease is treated by surgical debulking and adjuvant combination chemotherapy. The role of imaging is to detect and characterize adnexal masses as likely malignant, recognize unusual findings that may suggest atypical pathology, demonstrate metastases in order to prevent under-staging, and detect specific sites of disease that may be unresectable. These aims are directly related to clinical management; characterization of an adnexal mass as malignant guides appropriate surgical referral, recognition of atypical pathology such as malignant granulosa cell tumor in a young woman may be an indication for fertility-preserving surgery. Demonstration of metastatic site-assists surgical planning, and detection of unresectable disease may be an indication for neoadjuvant (ie, preoperative) chemotherapy with interval debulking rather than primary debulking with adjuvan (postoperative) chemotherapy.

Primary serous papillary carcinoma of the peritoneum: CT findings

AIM

To describe the computed tomography (CT) findings of primary serous papillary carcinoma of the peritoneum.

MATERIAL AND METHODS

The clinical data and imaging studies of 36 women aged 37-85 years with primary papillary serous carcinoma of the peritoneum were retrospectively evaluated. Twenty-seven patients presented with general abdominal complaints; all had elevated levels of CA-125. Thirty-two women were post-menopausal, four had had bilateral salpingo-oophorectomy.

RESULTS

The most common findings on pre-operative abdominal CT, performed in 30 patients, were a variable amount of ascites (n = 29), omental involvement (n = 28), irregular parietal peritoneum thickening (n = 22) and mural thickening of the sigmoid colon (n = 10). Thoracic findings included enlarged cardiophrenic nodes (n = 15) and pleural effusion (n = 11). Six patients had unilateral or bilateral adnexal masses of soft tissue density, which proved to be surface serous papillary carcinoma.

CONCLUSION

Diffuse peritoneal disease on CT in patients with normal-sized ovaries or following bilateral salpingo-oophorectomy, with elevated level of serum CA-125, but without an identifiable primary tumour, should suggest the diagnosis of primary serous papillary carcinoma of the peritoneum. Associated adnexal masses or focal bowel wall thickening may be seen, representing surface involvement by this tumour.