Notch-1 and Notch-4 biomarker expression in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) demonstrates lack of expression of hormone receptors and human epidermal growth factor receptor. However, there is no targeted therapy for TNBC. The authors analyzed 29 TNBC cases for Notch-1 and Notch-4 biomarker expression and subcellular location, Ki67 proliferation rate, and relevant clinical/survival data. Results demonstrated an unfavorable Ki67 rate in 90% of cases, Notch-1 expression in tumor and endothelial cells in 100% of cases, and Notch-4 expression in tumor cells in 73% of cases and endothelial cells in 100% of cases. Additionally, subcellular localization of Notch-1 and Notch-4 was predominantly nuclear and cytoplasmic. In conclusion, (a) the majority of TNBCs are high-grade infiltrating ductal carcinomas with high Ki67 proliferation rate and (b) both Notch-1 and Notch-4 receptors are overexpressed in tumor and vascular endothelial cells with subcellular localization different from that of hormone-positive breast cancer. Targeting Notch signaling with gamma secretase inhibitors should to be explored to further improve the survival rate of TNBC patients.

Pseudoangiomatous stromal hyperplasia (PASH) of the breast: a clinicopathological study of 79 cases.

BACKGROUND: Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign lesion that can present as a palpable nodule or as an incidental finding in breast biopsies. DESIGN: The study comprised 79 cases diagnosed at Loyola University Medical Center from 2002 to 2009. The pathology slides were reviewed to document the distribution, type, and association with preneoplastic or neoplastic epithelial lesions. Z-test for independent proportions is used for analysis. RESULTS: A total of 76 patients were female and 3 were male. In all, 59.8% of patients presented with a breast mass and in 40.2% the lesion was an incidental finding. Classical PASH morphology was seen in 97.6% and proliferative PASH in 2.4%. Associated epithelial lesions were benign proliferative changes in 60.4%, atypical ductal and atypical lobular hyperplasia in 25.6% and infiltrating carcinoma in 11% of cases. CONCLUSIONS: Based on these results, extensive sampling of biopsy specimen with PASH and appropriate clinical and radiologic follow-up is recommended.

Notch-1 and notch-4 receptors as prognostic markers in breast cancer.

BACKGROUND: Studies looking at immunohistochemical (IHC) staining of Notch receptors in breast cancer and correlation with known prognostic factors are sparse. METHODS: IHC staining for nuclear, cytoplasmic, and membrane Notch-1 (N1), Notch-4 (N4), and Jagged-1 (JAG1) was performed and correlated with known prognostic factors. RESULTS: Of 48 breast cancers, 36 (67%) were invasive, mean age was 50 years (range 43-86 years), 37 (77%) were estrogen receptor (ERα) positive, and 13 (27%) node positive. There was significantly more marked N1 membranous staining in ERα-positive tumors (P < .05). On univariate analysis, cytoplasmic N1 was significantly correlated with node status and tumor grade (P < .05); both cytoplasmic and membranous N4 significantly correlated with Ki67 (P < .05); and membranous JAG1 significantly correlated with Ki67 (P < .05). On multivariate analysis, only cytoplasmic N1 significantly correlated with node status. CONCLUSION: IHC of Notch markers is feasible and correlates with known prognostic factors consistent with a biological role of Notch signaling in breast cancer progression.

Inhibition of Notch signaling reduces the stem-like population of breast cancer cells and prevents mammosphere formation.

BACKGROUND: Cancer stem cells (CSCs) are believed to be responsible for breast cancer formation and recurrence; therefore, therapeutic strategies targeting CSCs must be developed. One approach may be targeting signaling pathways, like Notch, that are involved in stem cell self-renewal and survival. MATERIALS AND METHODS: Breast cancer stem-like cells derived from cell lines and patient samples were examined for Notch expression and activation. The effect of Notch inhibition on sphere formation, proliferation, and colony formation was determined. RESULTS: Breast cancer stem-like cells consistently expressed elevated Notch activation compared with bulk tumor cells. Blockade of Notch signaling using pharmacologic and genomic approaches prevented sphere formation, proliferation, and/or colony formation in soft agar. Interestingly, a gamma-secretase inhibitor, MRK003, induced apoptosis in these cells. CONCLUSION: Our findings support a crucial role for Notch signaling in maintenance of breast cancer stem-like cells, and suggest Notch inhibition may have clinical benefits in targeting CSCs.

Pseudoangiomatous stromal hyperplasia of the breast: a contemporary approach to its clinical and radiologic features and ideal management.

BACKGROUND: Pseudoangiomatous stromal hyperplasia (PASH) is a benign, proliferative lesion of the breast whose clinical relevance, presentation, and optimal treatment remains described incompletely. The purpose of this study is to review the clinical, radiologic, and histopathologic features and appropriate management. METHODS: Patients diagnosed with PASH were identified from our pathology database between 2000 and 2009. Clinicopathologic data including presentation, diagnosis, imaging, and histology were reviewed. All specimens were confirmed by a single pathologist. RESULTS: We identified PASH in 80 patients. Median follow-up was 3.71 years (range, 0.45-9.42). Age ranged from 12 to 65 (median, 45) and 95% were female. Lesions were palpable in 56% and found on imaging in the remainder. Core biopsy was performed in 65 of 80 patients (81%), which confirmed a diagnosis of PASH in 65%. The other 23 of 65 patients (35%) required operative excision for diagnosis. There was a progression rate of 26% in the observation arm versus 13% in the excision arm. A diagnosis of cancer or carcinoma in situ was seen in 30% at or before the diagnosis of PASH. CONCLUSION: PASH may present as a mass, radiologic lesion, or incidentally in pathology specimens. It may be associated with cancerous or precancerous lesions. A diagnosis on core biopsy in the absence of suspicious radiologic features may be managed with follow-up and imaging at a 6-month interval. In this series, 35% of patients with PASH had a negative core biopsy. Growth, suspicious radiologic findings, or inconclusive biopsy warrants surgical excision. Close surveillance is necessary given its recurrence rate of 13-26%.

Histopathologic characteristics of the primary tumor in breast cancer patients with isolated tumor cells of the sentinel node.

BACKGROUND: Clinicians often rely on primary tumor characteristics to decide on adjuvant treatment for patients with breast cancer with isolated tumor cells (ITC) in the sentinel lymph node. The purpose of this study was to determine if there is a significant difference in primary tumor characteristics between ITC and other nodal groups. METHODS: Patients undergoing sentinel lymphadenectomy were divided into 3 groups: N0, no metastases; ITC, metastasis less than 0.2 mm; and micro- or macrometastases (MM), metastasis greater than 0.2 mm. The chi-square test and analysis of variance were used. RESULTS: A total of 552 patients underwent sentinel lymphadenectomy; 197 (36%) had tumor-positive sentinel lymph nodes. Of these, 35 (18%) were classified as ITC and 162 (82%) as MM. When primary tumor characteristics were compared, the ITC group had significantly more lymphovascular invasion and higher proliferative rate than the N0 group (P < .05) and significantly less lymphovascular invasion, lower proliferative rate, and smaller tumor size (P < .05) than the MM group. There were no significant differences in the age, hormone receptor status, histologic type, or tumor grade among the patient groups. CONCLUSIONS: Proliferation and lymphovascular invasion of the primary tumor are significantly different between the ITC, N0, and MM groups suggesting that ITC tumors may have different biology than the N0 or MM tumors.

Cross-talk between notch and the estrogen receptor in breast cancer suggests novel therapeutic approaches.

High expression of Notch-1 and Jagged-1 mRNA correlates with poor prognosis in breast cancer. Elucidating the cross-talk between Notch and other major breast cancer pathways is necessary to determine which patients may benefit from Notch inhibitors, which agents should be combined with them, and which biomarkers indicate Notch activity in vivo. We explored expression of Notch receptors and ligands in clinical specimens, as well as activity, regulation, and effectors of Notch signaling using cell lines and xenografts. Ductal and lobular carcinomas commonly expressed Notch-1, Notch-4, and Jagged-1 at variable levels. However, in breast cancer cell lines, Notch-induced transcriptional activity did not correlate with Notch receptor levels and was highest in estrogen receptor alpha-negative (ERalpha(-)), Her2/Neu nonoverexpressing cells. In ERalpha(+) cells, estradiol inhibited Notch activity and Notch-1(IC) nuclear levels and affected Notch-1 cellular distribution. Tamoxifen and raloxifene blocked this effect, reactivating Notch. Notch-1 induced Notch-4. Notch-4 expression in clinical specimens correlated with proliferation (Ki67). In MDA-MB231 (ERalpha(-)) cells, Notch-1 knockdown or gamma-secretase inhibition decreased cyclins A and B1, causing G(2) arrest, p53-independent induction of NOXA, and death. In T47D:A18 (ERalpha(+)) cells, the same targets were affected, and Notch inhibition potentiated the effects of tamoxifen. In vivo, gamma-secretase inhibitor treatment arrested the growth of MDA-MB231 tumors and, in combination with tamoxifen, caused regression of T47D:A18 tumors. Our data indicate that combinations of antiestrogens and Notch inhibitors may be effective in ERalpha(+) breast cancers and that Notch signaling is a potential therapeutic target in ERalpha(-) breast cancers.

Predicting cancer on excision of atypical ductal hyperplasia.

BACKGROUND: There are no specific histopathologic factors that allow identification of patients with atypical ductal hyperplasia (ADH) who will have cancer on final excision. METHODS: This was a retrospective study of all patients who had ADH on biopsy followed by excision from 1999 to 2006. RESULTS: Fifty-one patients were found to have ADH on core biopsy. Eight (15.7%) patients had invasive carcinoma on surgical excision, 9 (17.5%) had ductal carcinoma-in-situ (DCIS), 21 (41.5%) had ADH, 4 (8%) patients had atypical lobular hyperplasia, and 9 (17.5%) had benign tumors. The grade of atypia on the core biopsy was mild in 13 (25%) patients, moderate in 22 (43%), and marked in 16 (32%). On multivariate analysis of histopathologic factors, the grade of atypia was the only significant variable that predicted a diagnosis of cancer on final surgical excision (P = .001). CONCLUSIONS: The grade of atypia correlated with the presence of cancer on surgical excision.

Pulmonary glomus tumor.

Glomus tumor (GT) is an infrequent but distinct neoplasm. Pulmonary GT is a rare neoplasm with only a few cases reported in the literature. These tumors are usually benign and, although rare, tumors with aggressive behavior have been reported. The tumor size, location, and histomorphological features may be useful in predicting tumor behavior. We present here a case of pulmonary GT that was initially diagnosed as a typical carcinoid tumor. The differential diagnosis as well as the recent classification of GTs is discussed along with a review of literature.

Prediction of nonsentinel lymph node metastasis in sentinel node-positive breast carcinoma.

The incidence of nonsentinel (NSN) lymph node metastases in patients with a tumor-positive sentinel (SN) lymph node varies greatly from 20% to 70% in the published literature. Current practice is that most patients with a positive SN (micro- and macrometastases) undergo a complete axillary dissection. However, it has been shown by other investigators that a large number of patients with a positive SN do not necessarily need a complete axillary dissection. In this analysis, we reviewed the pathology slides from 58 patients who had undergone SN and axillary node dissection. The tumor size, histologic parameters, receptor (estrogen and progesterone), and HER-2neu oncoprotein expression were noted. Student t test and Fisher exact test were used for statistical analysis. Of 58 patients, 19 (32.7%) had NSN metastases. Primary tumor size (P < .002), size of SN metastatic tumor (P < .03), and the presence of extracapsular tumor extension (P < .0001) were associated significantly with NSN metastases. We have shown in this study that it would be possible to predict the NSN status based on primary tumor size, size of SN metastatic tumor, and presence of SN extracapsular tumor extension.

Sentinel node status and tumor characteristics: a study of 234 invasive breast carcinomas.

CONTEXT: Axillary lymph node status is the most important prognostic factor in patients with breast cancer. Tumor size and lymph node status, the most reliable pathologic bases of the tumor staging system, are practical parameters for estimating survival status. With the advent of lymphatic mapping and sentinel node (SN) identification, there is potential for a more efficient and sensitive evaluation of the axillary lymph node status. OBJECTIVE: To correlate SN status with tumor size, grade, and lymphovascular invasion. DESIGN: We examined 234 patients with unifocal breast carcinomas measuring 25 mm or less as detected by preoperative ultrasound during the period May 1998 through December 2002. Sentinel nodes were examined by frozen section and paraffin section as per protocol. RESULTS: Of the 234 patients, SN was identified in 221 (94.5%). An average of 1.38 SNs were examined per patient. Seventy-seven of 221 patients were SN positive on paraffin section. Sixty-six (85.7%) of these 77 cases could be correctly diagnosed as positive for metastatic carcinoma on frozen section. Two cases reported as positive on paraffin section were reported as suspicious on frozen section. Logistic regression indicated that tumor size, grade, and lymphovascular invasion were all significantly associated with SN status (P < .001). CONCLUSIONS: Tumor size, grade, and lymphovascular invasion were significantly associated with SN status in unifocal invasive breast carcinoma.

Noninvasive carcinoma of the breast: angiogenesis and cell proliferation.

CONTEXT: Angiogenesis and the cell proliferation index can predict the prognosis of invasive breast carcinoma; however, little is known of their roles in noninvasive tumor. OBJECTIVE: To investigate the correlation of microvessel density and cell proliferation index with other histologic parameters (histologic type, nuclear grade, and mitotic count) in 65 cases of noninvasive carcinoma of the breast. DESIGN: Formalin-fixed, paraffin-embedded tissues from 65 cases of carcinoma in situ of the breast were immunostained with antibody against factor VIII antigen and proliferation-associated nuclear antigen MIB-1. The microvessel density was measured by counting the total number of microvessels around the carcinoma in situ per 10 low-power microscopic fields. The cell proliferation index was calculated by counting MIB-1-positive nuclei in 100 tumor cells. A chi2 test and Spearman rank correlation test were used for statistical analysis. RESULTS: The microvessel density and cell proliferation index of comedo-type, high-nuclear-grade ductal carcinomas in situ are significantly higher than those of either noncomedo type ductal carcinomas in situ or lobular carcinoma in situ (P <.001). CONCLUSIONS: Angiogenesis and the cell proliferation index are active biological processes and may be considered as markers to separate low- and high-risk patients with noninvasive breast carcinomas.