Peter E. Schwartz

Molecular phenotyping of human ovarian cancer stem cells unravels the mechanisms for repair and chemoresistance

A major burden in the treatment of ovarian cancer is the high percentage of recurrence and chemoresistance. Cancer stem cells (CSCs) provide a reservoir of cells that can self-renew, can maintain the tumor by generating differentiated cells [non-stem cells (non-CSCs)] which make up the bulk of the tumor and may be the primary source of recurrence. We describe the characterization of human ovarian cancer stem cells (OCSCs). These cells have a distinctive genetic profile that confers them with the capacity to recapitulate the original tumor, proliferate with chemotherapy, and promote recurrence. CSC identified in EOC cells isolated form ascites and solid tumors are characterized by: CD44+, MyD88+, constitutive NFκB activity and cytokine and chemokine production, high capacity for repair, chemoresistance to conventional chemotherapies, resistance to TNFα-mediated apoptosis, capacity to form spheroids in suspension, and the ability to recapitulate in vivo the original tumor. Chemotherapy eliminates the bulk of the tumor but it leaves a core of cancer cells with high capacity for repair and renewal. The molecular properties identified in these cells may explain some of the unique characteristics of CSCs that control self-renewal and drive metastasis. The identification and cloning of human OCSCs can aid in the development of better therapeutic approaches for ovarian cancer patients.

Diagnostic Markers for Early Detection of Ovarian Cancer

Purpose: Early detection would significantly decrease the mortality rate of ovarian cancer. In this study, we characterize and validate the combination of six serum biomarkers that discriminate between disease-free and ovarian cancer patients with high efficiency. Experimental Design: We analyzed 362 healthy controls and 156 newly diagnosed ovarian cancer patients. Concentrations of leptin, prolactin, osteopontin, insulin-like growth factor II, macrophage inhibitory factor, and CA-125 were determined using a multiplex, bead-based, immunoassay system. All six markers were evaluated in a training set (181 samples from the control group and 113 samples from OC patients) and a test set (181 sample control group and 43 ovarian cancer). Results: Multiplex and ELISA exhibited the same pattern of expression for all the biomarkers. None of the biomarkers by themselves were good enough to differentiate healthy versus cancer cells. However, the combination of the six markers provided a better differentiation than CA-125. Four models with <2% classification error in training sets all had significant improvement (sensitivity 84%-98% at specificity 95%) over CA-125 (sensitivity 72% at specificity 95%) in the test set. The chosen model correctly classified 221 out of 224 specimens in the test set, with a classification accuracy of 98.7%. Conclusions: We describe the first blood biomarker test with a sensitivity of 95.3% and a specificity of 99.4% for the detection of ovarian cancer. Six markers provided a significant improvement over CA-125 alone for ovarian cancer detection. Validation was performed with a blinded cohort. This novel multiplex platform has the potential for efficient screening in patients who are at high risk for ovarian cancer.

High-grade endometrial carcinoma in tamoxifen-treated breast cancer patients.

PURPOSE Several reports have associated tamoxifen administration with endometrial carcinoma. A retrospective study of the histologic features of uterine cancer in patients with a history of breast carcinoma was undertaken to determine the effect of treatment with tamoxifen. MATERIALS AND METHODS A computer search of the Yale-New Haven Hospital Tumor Registry from 1980 to 1990 identified 53 patients with a history of breast carcinoma who subsequently developed a malignant tumor of the uterine corpus. RESULTS Fifteen patients received tamoxifen for breast carcinoma and 38 did not. The mean ages of the two groups were not significantly different. The mean interval between detection of breast and endometrial cancers was 5 years in the tamoxifen group and 12 years in the nontreated group (P = .0023). Sixty-seven percent of patients in the tamoxifen group had poorly differentiated endometrioid carcinomas (including adenosquamous carcinoma) or carcinomas associated with poor outcome (eg, uterine papillary serous carcinoma, clear-cell carcinoma, or mixed müllerian tumor), as compared with 24% in the nontreated group (P = .03). Patients in the tamoxifen group were much more likely to die of endometrial cancer (33.3% v 2.6% of the nontreated group, P = .005). CONCLUSION From this retrospective study, it appears that women receiving tamoxifen as treatment for breast cancer who subsequently develop uterine cancer are at risk for high-grade endometrial cancers that have a poor prognosis. These findings also indicate that tamoxifen-associated uterine cancers may have a different basis from those associated with steroidal estrogen treatment.

BRCA1 and BRCA2 Mutation Analysis of 208 Ashkenazi Jewish Women with Ovarian Cancer

Ovarian cancer is a component of the autosomal-dominant hereditary breast-ovarian cancer syndrome and may be due to a mutation in either the BRCA1 or BRCA2 genes. Two mutations in BRCA1 (185delAG and 5382insC) and one mutation in BRCA2 (6174delT) are common in the Ashkenazi Jewish population. One of these three mutations is present in approximately 2% of the Jewish population. Each mutation is associated with an increased risk of ovarian cancer, and it is expected that a significant proportion of Jewish women with ovarian cancer will carry one of these mutations. To estimate the proportion of ovarian cancers attributable to founding mutations in BRCA1 and BRCA2 in the Jewish population and the familial cancer risks associated with each, we interviewed 213 Jewish women with ovarian cancer at 11 medical centers in North America and Israel and offered these women genetic testing for the three founder mutations. To establish the presence of nonfounder mutations in this population, we also completed the protein-truncation test on exon 11 of BRCA1 and exons 10 and 11 of BRCA2. We obtained a detailed family history on all women we studied who had cancer and on a control population of 386 Ashkenazi Jewish women without ovarian or breast cancer. A founder mutation was present in 41.3% of the women we studied. The cumulative incidence of ovarian cancer to age 75 years was found to be 6.3% for female first-degree relatives of the patients with ovarian cancer, compared with 2.0% for the female relatives of healthy controls (relative risk 3.2; 95% CI 1.5-6.8; P=.002). The relative risk to age 75 years for breast cancer among the female first-degree relatives was 2.0 (95% CI 1.4-3.0; P=.0001). Only one nonfounder mutation was identified (in this instance, in a woman of mixed ancestry), and the three founding mutations accounted for most of the observed excess risk of ovarian and breast cancer in relatives.

Psychosocial benefits of a cancer support group

Many clinicians use group support to reduce the psychosocial difficulties of persons with cancer. This study compared the long‐term benefits of a thematic counseling model used both as a structure for group support and for counseling patients individually. The thematic model included eight counseling sessions focused on information about cancer and positive health strategies such as progressive relaxation, diet, and exercise. The psychosocial status of women newly diagnosed with gynecologic cancer was assessed before the counseling, immediately after counseling, and again 6 months later. The women who participated in thematic counseling were significantly less depressed and less anxious and had more knowledge of their illness, better relationships with care givers, fewer sexual difficulties, and more participation in leisure activities. Data confirmed the model to be equally helpful whether it was used as a structure for individual counseling or more cost‐effective group counseling. This model is easily adaptable to the needs of persons with other forms of cancer.

Preoperative abdominopelvic computed tomographic prediction of optimal cytoreduction in epithelial ovarian carcinoma.

PURPOSE This study was undertaken to assess the ability of computed tomography (CT) to predict the likelihood of optimal primary tumor cytoreduction in women with epithelial ovarian carcinoma. PATIENTS AND METHODS Fifty-one women with preoperative CT and a histologic diagnosis of epithelial ovarian carcinoma following primary tumor operation by a gynecologic oncologist were identified. Forty-two CT scans were retrospectively analyzed. CT findings of attachment of the omentum to the spleen or disease greater than 2 cm on the diaphragm, liver surface, or parenchyma, pleura, mesentery, gallbladder fossa, or suprarenal paraaortic nodes were coded to represent unresectable disease. CT results were compared with surgical outcome. RESULTS Twenty-nine of 42 (69%) patients underwent optimal cytoreduction to less than 2 cm residual disease. Successful cytoreduction was accomplished in 23 of 24 patients who fulfilled CT criteria for cytoreduction and six of 18 with CT criteria predictive of inability to perform cytoreduction. CT was highly sensitive for detection of ascites, mesenteric, and omental disease, but was poor for detection of liver involvement, omental attachment to the spleen, gallbladder fossa disease, and peritoneal nodules smaller than 2 cm. The CT findings accurately predicted surgical outcome with a sensitivity of 92.3% and specificity of 79.3%. The positive predictive value was 67% and the negative predictive value was 96%. CONCLUSION CT scan is an accurate method for the prediction of successful surgical cytoreduction and may have utility in the decision to offer neoadjuvant chemotherapy to certain medically disabled patients, a hypothesis currently under evaluation.

Low-grade endometrial stromal sarcoma: hormonal aspects☆

OBJECTIVE The goal of this work was to determine whether exposure to estrogen following treatment of low-grade endometrial stromal sarcomas affects clinical outcome. METHODS Twenty-two patients with low-grade endometrial stromal sarcomas were reviewed to determine whether they were exposed to exogenous or endogenous estrogen and/or progestins following their diagnosis and whether exposure to these hormones might have influenced their prognosis. Estrogen receptor (ER) alpha and beta and progestin receptor (PR) status were analyzed from paraffin-embedded tissue by immunohistochemistry and ER mRNA was measured in fresh tissue by reverse transcription polymerase chain reaction (RT-PCR). RESULTS Ten of the twenty-two patients with low-grade endometrial stromal sarcomas developed recurrent disease. Four of five patients (80%) who received estrogen replacement therapy (ERT) recurred. Four of eight patients (50%) with retained ovaries recurred. Eight of the ten specimens available for analysis were positive for ERalpha, none were positive for ERbeta, and 9 of 10 were positive for PR. Four of thirteen patients who received progestins as adjuvant therapy recurred, compared with 6 of 9 patients who did not receive progestins (31% vs 67%). Eight recurrences were treated with progestin therapy and 7 (88%) of them had either stable disease (3/8, 38%) or complete response (4/8, 50%). CONCLUSIONS Our results suggest that ERT may be detrimental in patients with low-grade endometrial stromal sarcoma. Retention of normally functioning ovaries, on the other hand, may not significantly affect the recurrence rate following hysterectomy alone in Stage I patients. The lack of ERbeta expression in endometrial stromal sarcomas compared with normal endometrial stromal cells suggests that loss of ERbeta may be a marker for malignancy. Progestin therapy should be routinely considered for adjuvant therapy and for the treatment of recurrent endometrial stromal sarcomas.

Reproductive function after conservative surgery and chemotherapy for malignant germ celltumors of the ovary

OBJECTIVE To analyze the long-term effects on reproductive function of fertility-preserving treatment for malignant germ cell tumors of the ovary. METHODS A case series analysis was performed on patients with malignant germ cell tumors of the ovary seen or consulted on at our institution between 1975 and 1995. Follow-up information regarding reproductive function was obtained by a mailed or telephone questionnaire. RESULTS A total of 106 patients with malignant germ cell tumors of the ovary were included in the study. Twenty patients were excluded because of loss of follow-up or death. For the remaining 86 patients, the median follow-up was 122 months (24–384 months). Fertility-preserving surgery was performed in 64 patients. Thirty-eight have attempted conception and 29 have achieved at least one pregnancy (76%). Among the patients who conceived, 20 were International Federation of Gynecology and Obstetrics (FIGO) stage I, one was stage II, and eight were stage III. Sixteen received vincristine, actinomycin D, and cyclophosphamide; three received cisplatin, vinblastine, and bleomycin; three received bleomycin, etoposide, and cisplatin; one received etoposide and cisplatin; four did not receive any chemotherapy; and two were treated with other combinations. Among the nine patients who could not conceive, seven were FIGO stage I and two were stage III. Four of these patients received vincristine, actinomycin D, and cyclophosphamide; three received etoposide and cisplatin; one received cisplatin, vinblastine, and bleomycin; and one patient received no chemotherapy. A total of 38 children were born to these women. Follow-up was available for 16 of these children, who have no evidence of congenital anomalies. CONCLUSION Fertility-preserving surgery followed by chemotherapy, even in advanced-stage malignant germ cell tumors of the ovary, is effective in conserving the reproductive function of women with malignant germ cell tumors of the ovary.

Landscape of somatic single-nucleotide and copy-number mutations in uterine serous carcinoma

Uterine serous carcinoma (USC) is a biologically aggressive subtype of endometrial cancer. We analyzed the mutational landscape of USC by whole-exome sequencing of 57 cancers, most of which were matched to normal DNA from the same patients. The distribution of the number of protein-altering somatic mutations revealed that 52 USC tumors had fewer than 100 (median 36), whereas 5 had more than 3,000 somatic mutations. The mutations in these latter tumors showed hallmarks of defects in DNA mismatch repair. Among the remainder, we found a significantly increased burden of mutation in 14 genes. In addition to well-known cancer genes (i.e., TP53, PIK3CA, PPP2R1A, KRAS, FBXW7), there were frequent mutations in CHD4/Mi2b, a member of the NuRD–chromatin-remodeling complex, and TAF1, an element of the core TFIID transcriptional machinery. Additionally, somatic copy-number variation was found to play an important role in USC, with 13 copy-number gains and 12 copy-number losses that occurred more often than expected by chance. In addition to loss of TP53, we found frequent deletion of a small segment of chromosome 19 containing MBD3, also a member of the NuRD–chromatin-modification complex, and frequent amplification of chromosome segments containing PIK3CA, ERBB2 (an upstream activator of PIK3CA), and CCNE1 (a target of FBXW7-mediated ubiquitination). These findings identify frequent mutation of DNA damage, chromatin remodeling, cell cycle, and cell proliferation pathways in USC and suggest potential targets for treatment of this lethal variant of endometrial cancer.

Pretreatment prognostic factors in carcinoma of the uterine cervix: a multivariable analysis of the effect of age, stage, histology and blood counts on survival.

From January, 1953 through December, 1977, 910 previously untreated patients with invasive carcinoma of the uterine cervix (Stages IB-IVB) were seen at Yale-New Haven Medical Center and affiliated hospitals. An extensive retrospective analysis was undertaken in an attempt to identify prognostically significant pretreatment factors. The patients studied were uniformly staged according to the current FIGO recommendations and the majority of patients had been treated under standardized protocols combining external beam radiation therapy and intracavitary radium. Pretreatment parameters, including prior medical illnesses, gross tumor characteristics, histology, and blood parameters were studied, employing stepwise Cox regression analyses to identify the possible effects of all factors and all two-way interactions among factors on survival, disease-free survival and freedom from local-regional failure, controlling for stage of disease. FIGO stage, patient age at diagnosis, pretreatment neutrophil count and hematocrit, uterine position, prior subtotal hysterectomy, histology, history of diabetes mellitus and number of pregnancies were all found to have prognostic significance. When other factors including stage of disease were controlled for, increased tumor size was associated with decrease disease-free survival and local-regional control rates.