Richard L. Kempson

A recent trend in the classification of uterine smooth muscle neoplasms (USMNs) into clinically benign and clinically malignant groups has been to move from exclusive reliance upon mitotic index (MI) to an approach that incorporates additional histopathologic characteristics. In furtherance of this goal, we assessed a variety of histopathologic features of 213 problematic smooth muscle neoplasms for which we had > or = 2 years of clinical follow-up data or for which there was an unfavorable outcome. One hundred and thirteen of these patients have had a minimum follow-up of 5 years, and 48 have been followed for > or = 10 years. Cases eliminated from the study group included USMNs with a significant myxoid or epithelioid component and cases of intravenous leiomyomatosis. USMNs, whether cellular or not, with no cytologic atypia and with a mitotic index (MI = number of mitotic figures [mf]/10 high-power fields [hpf]) of < 5 mf/10 hpf (usual leiomyomas) were also excluded unless they had unusual features or were associated with an adverse clinical outcome. Fifty-six patients were initially treated by myomectomy or another form of local tumor removal; the remainder had a hysterectomy. From a wide variety of light microscopic features assessed, the important predictors that emerged, using a variety of data exploratory techniques, were MI, the degree of cytologic atypia, and the presence or absence of coagulative tumor cell necrosis (CTCN). Stratification of the USMNs with respect to these three features resulted in a five-group classification of USMNs with the following major characteristics. Group 1: Of the 89 USMNs with an MI in the range 5 < or = MI < 20 without CTCN and with no more than mild atypia, 88 were clinically benign. One patient with a tumor in this group died of metastatic disease 96 months after her uterine cervical primary neoplasm was removed. Combining our data with that in the literature, the failure rate in this group is approximately 1/200 (0.5%). This low failure rate warrants the use of the label "leiomyoma with increased mitotic index" for USMNs with these histologic features. Two patients whose USMNs were characterized by mild atypia, no necrosis, and MI < 5 developed identical-appearing pulmonary metastases and were judged in retrospect to have the syndrome "benign metastasizing leiomyoma." Group 2: USMNs with no CTCN and diffuse moderate to severe atypia fell into two groups based on the MI. For those patients whose neoplasms had an MI > or = 10 mf/10 hpf, four of 10 failed.(ABSTRACT TRUNCATED AT 400 WORDS)

A review of 256 cases of pathologic Stage I uterine adenocarcinoma treated at Stanford University Hospital revealed 26 cases of uterine papillary serous carcinoma (UPSC), a clinically aggressive and morphologically distinct variant of adenocarcinoma which closely resembles ovarian papillary serous carcinoma. These lesions are easily recognized by microscopic examination and typically feature a high degree of cytologic anaplasia and a papillary growth pattern. Invasion of the lymphatics has been a frequent finding. The relapse rate among patients with pathologic Stage I UPSC was 50% (13/26), five times the rate which would have been predicted by the incidence of UPSC. Patients with Stage I UPSC fared significantly worse than the group of nonpapillary grade II or grade III adenocarcinomas (p less than 0.0001). Forty percent of Stage I UPSC patients had deep myometrial invasion, as compared with 12% of those with all other histologic types of adenocarcinoma (p = 0.001). Women with UPSC deeply invading the myometrium tended to do worse than those with deeply invasive lesions of the more usual endometrioid type as reflected by relapse rates (after surgery alone) of 63% and 30%, respectively. Of seven Stage I corpus carcinoma patients whose initial site of failure was in the upper abdomen, six had UPSC. Thus, UPSC shares the tendency of its ovarian counterpart to spread over peritoneal surfaces. In addition to the original study group of 26 Stage I patients, 34 patients with more advanced stages of UPSC were also reviewed. Of these, 26 have been followed and four survive. Eleven of these women presented or relapsed with abdominal carcinomatosis. UPSC is a clinically aggressive neoplasm which should be distinguished from other types of primary endometrial adenocarcinoma. In cases of invasive UPSC the mode of spread, similar to that of ovarian surface epithelial carcinomas, suggests the need for adjuvant upper abdominal and pelvic irradiation or effective chemotherapy.

Histological evaluation of endometrium has been the gold standard for clinical diagnosis and management of women with endometrial disorders. However, several recent studies have questioned the accuracy and utility of such evaluation, mainly because of significant intra- and interobserver variations in histological interpretation. To examine the possibility that biochemical or molecular signatures of endometrium may prove to be more useful, we have investigated whole-genome molecular phenotyping (54,600 genes and expressed sequence tags) of this tissue sampled across the cycle in 28 normo-ovulatory women, using high-density oligonucleotide microarrays. Unsupervised principal component analysis of all samples revealed that samples self-cluster into four groups consistent with histological phenotypes of proliferative (PE), early-secretory (ESE), mid-secretory (MSE), and late-secretory (LSE) endometrium. Independent hierarchical clustering analysis revealed equivalent results, with two major dendrogram branches corresponding to PE/ESE and MSE/LSE and sub-branching into the four respective phases with heterogeneity among samples within each sub-branch. K-means clustering of genes revealed four major patterns of gene expression (high in PE, high in ESE, high in MSE, and high in LSE), and gene ontology analysis of these clusters demonstrated cycle-phase-specific biological processes and molecular functions. Six samples with ambiguous histology were identically assignable to a cycle phase by both principal component analysis and hierarchical clustering. Additionally, pairwise comparisons of relative gene expression across the cycle revealed genes/families that clearly distinguish the transitions of PE-->ESE, ESE-->MSE, and MSE-->LSE, including receptomes and signaling pathways. Select genes were validated by quantitative RT-PCR. Overall, the results demonstrate that endometrial samples obtained by two different sampling techniques (biopsy and curetting hysterectomy specimens) from subjects who are as normal as possible in a human study and including those with unknown histology, can be classified by their molecular signatures and correspond to known phases of the menstrual cycle with identical results using two independent analytical methods. Also, the results enable global identification of biological processes and molecular mechanisms that occur dynamically in the endometrium in the changing steroid hormone milieu across the menstrual cycle in normo-ovulatory women. The results underscore the potential of gene expression profiling for developing molecular diagnostics of endometrial normalcy and abnormalities and identifying molecular targets for therapeutic purposes in endometrial disorders.

We present the results of a clinicopathologic study of 109 patients with endometrial stromal sarcoma and eight patients with endometrial stromal nodule. Of the 109 patients with endometrial stromal sarcoma, follow-up was obtained on 93 (85%). The stage distribution of the patients with stromal sarcoma and the number of patients with follow-up (numerator) compared to the total number of patients in each stage (denominator) are: Stage 1.73/85: Stage 11.3/6: Stage III.11/11: Stage IV, 6/7. Stage II patients are considered separately in the analysis. Thirtysix percent of the Stage I patients experienced one or more relapses. Of these, six (23%) died of disease from 11 to 360 months from diagnosis (median, 79 months). Nine (35%) were alive with disease. Of the eleven Stage III patients, eight had one or more relapses and of these, six died of disease. Of the six Stage IV patients. five had one or more relapses and of these, three died of disease. The outcome differences between Stages I, III, and IV are statistically significant (p < .01). Microscopic features evaluated included the mitotic index (MI = number of mitoses/10 high-power fields) and cytologic atypia. Forty-five percent of Stage I patients who had both rare mitotic figures and minimal atypia had one or more relapses and of these, two (13%) died of disease at 85 and 360 months, respectively. Thus, neither MI nor cytologic atypia were predictive of tumor recurrence for patients with Stage I tumors.

Although the categorization of proliferative breast lesions provides valuable information regarding subsequent risk of breast cancer, the ability of pathologists to classify such lesions in a reproducible fashion has not been adequately evaluated. To assess further interobserver reproducibility in the categorization of proliferative breast lesions, six pathologists each reviewed 24 proliferative ductal lesions and classified them as either usual hyperplasia (H), atypical hyperplasia (AH), or carcinoma in situ (CIS). Before evaluation of the study slides, all the participants were instructed to use the diagnostic criteria of Page and co-workers and were provided with both a written summary of these criteria and a set of teaching slides with representative examples of each type of lesion. Complete agreement among all six pathologists was seen in 14 cases (58%); five or more agreed in 17 cases (71%); and four or more arrived at the same diagnosis in 22 cases (92%). No pathologist consistently rendered more “benign” or “malignant” diagnoses than any other. After assigning numerical values for each diagnostic category (H = 1, AH = 2, CIS = 3), the scores for the group of 24 cases did not differ significantly by pathologist (p = 0.68; average score range, 1.7–2.0). Our results indicate that with the use of standardized criteria, interobserver concordance in the diagnosis of proliferative ductal breast lesions can be obtained in the majority of cases.