Clinical aspects of ovarian tumors of low malignant potential

Ovarian serous borderline tumors: a critical review of the literature with emphasis on prognostic indicators

BACKGROUND

The behavior of ovarian serous borderline tumors (SBTs) and significance of various prognostic factors are unclear and difficult to evaluate because of inconsistencies and confusion in the literature. Recent studies have suggested that the morphological features of the primary tumor (presence or absence of micropapillary features) and the peritoneal "implants" (presence or absence of invasive features) can reliably subclassify SBTs into benign and malignant types. The aim of the current review was to test two hypotheses. First, that the alleged malignant behavior of SBTs is poorly documented, and second, that the morphological features of the primary ovarian tumors and the associated peritoneal implants are sufficient to separate SBTs into benign and malignant types, thereby obviating the need for the category.

METHODS

245 studies reporting approximately 18,000 patients with borderline ovarian tumors were reviewed. After excluding series that lacked clinical follow-up or were not analyzable for other reasons, there remained 97 reports that included 4,129 patients. In addition to recurrences and survival, we evaluated the type of peritoneal implants, microinvasion, lymph node involvement, late recurrences, and progression to carcinoma, as these features have served as the underpinning of the concept of "borderline malignancy" or "low malignant potential."

RESULTS

Among 4,129 patients with SBTs reviewed, the recurrence rate after a mean follow-up of 6.7 years was 0.27% per year for stage I tumors, the disease-free survival was 98.2%, and the overall disease-specific survival rate was 99.5%. For patients with advanced-stage tumors, the recurrence rate was 2.4% per year. However, the majority (69%) of reported recurrences were not pathologically documented, and only 26 cases (8.4% of all recurrences) were documented to have recurred from an adequately sampled ovarian tumor. The most reliable prognostic indicator for advanced stage tumors was the type of peritoneal implant. After 7.4 years of follow-up, the survival of patients with noninvasive peritoneal inplants was 95.3%, as compared with 66% for invasive implants (P < .0001). Microinvasion in the primary ovarian tumor was associated with a 100% survival rate at 6.7 years, and lymph node involvement was associated with a 98% survival rate at 6.5 years. The few reported cases of stage IV disease, progression to invasive carcinoma, and very late (>20 years) recurrences were poorly documented. The survival for all stages among approximately 373 patients in 6 prospective randomized trials followed for a mean of 6.7 years was 100%.

CONCLUSION

Surgical pathological stage and subclassification of extraovarian disease into invasive and noninvasive implants are the most important prognostic indicators for SBTs. Survival for stage I tumors is virtually 100%. Survival for advanced stage tumors with noninvasive implants is 95.3%, whereas survival for tumors with invasive implants is 66%. Invasive implants behave as carcinomas and are most likely metastatic. The precise nature of so-called noninvasive implants is not clear, but they behave in a benign fashion. The presence of a micropapillary architecture in the primary ovarian tumor is a strong predictor of invasive implants. These data support the recommendation that ovarian tumors with a micropapillary architecture be designated "micropapillary serous carcinomas," and those lacking these features, "atypical proliferative serous tumors."

The management of borderline epithelial tumors of the ovary

The histopathological diagnosis and treatment of borderline epithelial tumors of the ovary (BTO) still pose problems to both pathologists and gynecologists. BTO is a disease of younger, fertile females and generally has an excellent prognosis. A minority of patients, however, succumb to this disease. A review of the literature is given addressing aspects of epidemiology, histology, treatment and prognosis, resulting in a proposal for the management of serous and mucinous borderline tumors of the ovary.

Borderline ovarian malignancy: ultrasound and fast dynamic MR findings

Ovarian tumors of borderline malignancy are low-grade malignant neoplasms, and have a rather good prognosis. They account for approximately 10-20% of all ovarian tumors. Very few reports available in literature that analyses ultrasound and MR findings in establishing the diagnosis. The purpose of this study is to describe eight cases of ovarian tumors of borderline malignancy with dynamic gadolinium-enhanced MR imaging. Comparison is made with CA 125 serum levels and ultrasound findings. Early enhancing endocystic vegetations, local cystic masses in, and (irregular) thickened walls of large multicystic tumors were important findings in borderline malignant tumors. The accuracy to detect a malignant tumor of borderline malignancy with CA 125, ultrasound and MRI in these eight cases was 50, 63 and 75%, respectively. MRI is a valuable imaging modality to characterize adnexal tumors and might play a role in preoperative evaluation of borderline malignancies.

Sonographic and Doppler flow characteristics of ovarian tumors of low-malignant potential

OBJECTIVE

To outline the sonographic and color Doppler flow imaging characteristics of ovarian tumors of low-malignant potential (OCLMP).

METHODS

Fourteen women with ovarian tumors of low-malignant potential were compared with 26 women with ovarian cystadenomas and 23 with ovarian carcinomas.

RESULTS

Sonographically, more complex structures and echogenic lesions were found in the OCLMP and malignant tumors than in the cystadenomas, and the difference was statistically significant. Color blood flow imaging revealed a similar resistant index (RI) in the OCLMP (0.487 +/- 0.07) and cystadenomas (0.489 +/- 0.09) when compared with statistically significant lower RI in the ovarian carcinomas (0.391 +/- 0.05) (P < 0.001).

CONCLUSIONS

Among young women, the combination of a complex ovarian mass with turbid fluid and echogenic lesions whose color Doppler flow imaging registers in the low range (RI < 0.5) should raise the suspicion of an ovarian tumor of low-malignant potential.

Borderline ovarian tumors

Borderline tumor of the ovary (BOT) is an epithelial tumor with a low rate of growth and a low potential to invade or metastasize. This tumor often is associated with a significantly better prognosis than epithelial ovarian cancer. Most tumors are either serous or mucinous in histology and present as early stage lesions. However, stage III lesions with peritoneal implants are not uncommon. Patients with early stage lesions have an excellent prognosis. Patients with higher stage lesions have a worse prognosis. Long-term follow-up of patients with BOT is required since the tumor can recur up to 20 years after the initial diagnosis. Recently, investigators have begun to identify subsets of patients with a worse prognosis, such as patients with aneuploid tumors. Treatment for early stage lesions is surgical and conservative surgery can be accomplished successfully in younger patients who desire to maintain fertility. Treatment for later stage lesions has been approached in a variety of ways. All approaches initially begin with maximal cytoreductive surgery. Studies suggest that early stage disease should be managed with surgery alone. Conflicting results on the usefulness of adjuvant therapy for patients with later stage disease have been obtained. At this time, the usefulness of adjuvant therapy for advanced disease remains undetermined. Further understanding of the basis of the disease and analysis of specific higher risk subsets might identify patients in whom adjuvant therapy could be tested in the setting of controlled clinical trials.

Current concepts in management of epithelial ovarian tumors of low malignant potential

Approximately 15 percent of epithelial ovarian tumors are tumors of LMP. Epithelial stratification, cellular atypia, mitotic activity, and abscence of ovarian stromal invasion set the histopathological criteria for diagnosis. Serous and mucinous tumors of LMP represent 80 to 95% of all cases. These tumors occur in patients at a younger age than those with invasive cancer and many times in fertile women who have not accomplished their family planning yet. Ovarian tumors of low malignant potential carry a favorable prognosis in comparison to invasive epithelial ovarian cancer. The recurrence rate after surgery for these tumors ranges from 10 percent to 30 percent, occurring as late as 10 or more years after presentation. The majority of patients (80-92 percent) with ovarian tumors of LMP present with stage I disease. Peritoneal implants display a range of histologic appearances, ranging from benign glands to those with features of invasive disease. Tumor markers such as CA-125 are not as useful in tumors of LMP as in invasive ovarian carcinoma. Elevated CA-125 are found only in patients with advanced serous tumors of LMP; thus, other markers such as transvaginal Doppler measurements of vascular resistant index has been suggested for possible differentiation between a benign and LMP ovarian tumors before surgery. Primary conservative surgery consisting of unilateral salpingo-oophorectomy is considered to be an appropriate treatment for young women with stage Ia ovarian tumors of LMP who wish to retain their fertility potential. Up to 70 percent of women who underwent conservative surgery subsequently conceive.(ABSTRACT TRUNCATED AT 250 WORDS)

A retrospective study of 370 borderline tumors of the ovary treated at the Norwegian Radium Hospital from 1970 to 1982. A review of clinicopathologic features and treatment modalities

METHODS

Three-hundred seventy patients with borderline tumors treated between 1970 and 1982 at the Norwegian Radium Hospital were analyzed retrospectively for clinicopathologic features, treatment, and survival characteristics.

RESULTS

One hundred seventy-eight patients had mucinous tumors, 174 patients had serous tumors, and 18 patients had other types of tumors. There were 311 patients with Stage I, 20 with Stage II, and 39 with Stage III tumors by the classification of the International Federation of Gynecology and Obstetrics. Most of the patients were treated in conformity with the protocols for invasive carcinoma at the current time. Total abdominal hysterectomy, bilateral adnexectomy, and omentectomy were performed in 287 patients and less extensive surgery was performed in 77 patients. Only six patients had residual tumor after surgery. The independent prognostic factors evaluated by Cox analysis in regard to corrected (dead of disease) short-term and long-term survival were stage (P < 0.0001) and histologic type (P = 0.0144); age (P = 0.0115) affected only long-term survival. Adjuvant treatment was of no benefit.

CONCLUSIONS

Stage, histologic type, and age had prognostic significance. Fertility-saving surgery can be offered to patients with Stage IA disease with serous or mucinous tumors.

Borderline epithelial ovarian tumors: a review of 81 cases with an assessment of the impact of treatment

Optimal management of borderline epithelial ovarian tumors remains controversial because of the lack of clear, universally accepted pathologic criteria for diagnosis, the lack of complete understanding of the significance of intraperitoneal implants, and the desire to employ more limited surgery in young women. We reviewed the experience with borderline epithelial ovarian tumors at Princess Margaret Hospital in order to assess the natural history of the disease, to determine prognostic factors that would aid in management decisions, and to determine if adjuvant therapy influenced outcome. Eighty-one patients were analyzed. The mean age was 48 years. Seventy-two percent of tumors were of the serous histologic sub-type and 28% were mucinous. Seventy-eight percent were Stage I, 11% Stage II, and 11% Stage III. Peritoneal washings contained malignant cells in 14 of 32 patients (not recorded or obtained in 49), cyst rupture occurred in 25%, surface excrescences in 40%, and adhesions in 46%. None of these factors had a significant effect on recurrence rate or survival. Eleven patients received adjuvant radiation therapy (10 abdomino-pelvic and 1 pelvic alone), four adjuvant chemotherapy, and one both radiation therapy and chemotherapy. The rest (65) received no adjuvant therapy. Due to the small numbers and infrequent events, it was not possible to analyze and thus draw valid conclusions regarding the effect of adjuvant therapy on survival or recurrence. The overall survival (OS) and cause specific survival (CSS) were 85% and 96% at 10 years, respectively. No Stage I patient died of tumor. OS for Stage I patients was 90% at 10 years, the majority of whom (61 of 63) received no adjuvant therapy, and is thus unnecessary in Stage I disease. The adequacy of unilateral oophorectomy or ovarian cystectomy could not be confirmed because of small numbers. The 10 year OS and disease-free survival in Stage II and III were 75% and 50%, respectively, despite the use of adjuvant radiation therapy, chemotherapy, or both. It is necessary to create a multi-center tumor registry in order to acquire a prospective data base from which to develop sound therapeutic decisions.