Accuracy of frozen section diagnosis in gynecology

Accuracy of frozen section for the operative management of endometrial cancer

OBJECTIVE

To assess the accuracy of intra-operative frozen section reports at identifying the features of high risk uterine disease compared with final histopathology.

DESIGN

Retrospective study.

METHODS

The records of 460 patients with uterine cancer registered with the Queensland Centre for Gynaecological Cancer between January 1, 1996 and December 31, 1998 were reviewed. Intra-operative frozen section was undertaken in 260 patients with endometrial adenocarcinoma. Frozen section pathology was compared with the final histopathology reports. Inter-observer reliability was assessed using percentage agreement and kappa statistics. Clinical notes were also reviewed to determine if errors resulted in sub-optimal patient care.

RESULTS

Respectively, tumour grade and depth of myometrial invasion were accurately reported in 88.6% of cases (expected 61.5%, Kappa 0.70) and 94.7% (expected 53.8%, Kappa 0.89). Errors were predominantly attributable to difficulties with respect to the interpretation of tumour grade. The error resulted in the patient receiving sub-optimal surgical management in only 11 cases (5.3%)

CONCLUSION

Frozen section is accurate at identifying the features of high risk uterine disease in the setting of endometrial cancer and can play an important role in directing primary operative management.

Accuracy of intraoperative frozen section diagnosis of ovarian tumors

OBJECTIVE

The goal of this work was to evaluate retrospectively, as quality control, the accuracy of frozen section diagnosis in ovarian tumors.

METHOD

We compared 243 frozen section results with the final diagnosis in paraffin sections, from cases studied from January 1994 to April 1999.

RESULTS

Results with the two methods were analyzed on two parameters: (a) malignant potential and (b) histological type. As for malignant potential, frozen section diagnosis agreed with the paraffin diagnosis in 94% of all cases (98.5% for malignant tumors, 94% for benign tumors, and 78.6% for borderline tumors). There was one false-positive and 13 false-negative cases. Sensitivity and specificity values for malignant tumors were 93 and 99%; for borderline tumors, 61 and 99%; and for benign tumors, 98 and 93%. With respect to histological type, in 203 cases (84%) the pathologists had no doubt in the diagnosis; in 40 cases (16%) diagnosis was given as "compatible with." In 35 of these (87.5%) the initial diagnosis was confirmed by paraffin.

CONCLUSION

Frozen section diagnosis seems to be a reliable method for ovarian tumors, with high sensitivity for malignant neoplasms and a low false-positive rate which allow the best choice of treatment. The most frequent problems arise with borderline and granulosa cell tumors.

Reliability of frozen section of uterine curettings in evaluation of possible ectopic pregnancy

STUDY OBJECTIVE

To assess the accuracy of frozen section evaluation of uterine curettings to look for chorionic villi and rule out ectopic pregnancy before laparoscopy.

DESIGN

Retrospective review (Canadian Task Force classification III).

SETTING

Northeastern medical school-affiliated teaching hospital.

PATIENTS

Thirty-six women. Intervention. Dilatation and curettage, laparoscopy, and laparotomy.

MEASUREMENTS AND MAIN RESULTS

Of 36 cases, 13 showed evidence of intrauterine pregnancy, either chorionic villi or implantation site, on final permanent sections. Five false negatives were identified in which no villi were identified on frozen section, although villi or evidence of an implantation site was noted on permanent sections (sensitivity 62%, 95% CI 0.32, 0.86).

CONCLUSION

Frozen section evaluation of uterine curettings can produce false negative diagnoses, and this should be considered in the operative planning of women with suspected ectopic pregnancy.

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."