Uma Krishnamurti

HER2 in breast cancer: a review and update.

HER2 (human epidermal growth factor receptor 2) receptor is a membrane tyrosine kinase and when activated affects cell proliferation and survival. The HER2 oncogene is located on chromosome 17q12. HER2 amplification is the primary pathway of HER2 receptor overexpression and is a major driver of tumor development and progression in a subset of breast cancers. HER2 is amplified in about 15% to 20% of breast cancers. The overexpressed HER2 receptor is a valuable therapeutic target. The 2007 ASCO guidelines mandate that HER2 should be evaluated in every invasive breast cancer, either at the time of diagnosis or recurrence to guide therapy. Currently HER2 testing is carried out by several methods. It is crucial to standardize testing techniques to accurately assess HER2 status. The aim of this review on HER2 in breast cancer is to discuss the important aspects of HER2 biology, its significance in breast cancer, and the current standards for its detection.

Poor prognostic significance of unamplified chromosome 17 polysomy in invasive breast carcinoma.

The human epidermal growth factor receptor 2 (HER2) oncoprotein is overexpressed in about 20% of breast cancers, with HER2 gene amplification responsible for protein overexpression in the vast majority of patients. A subset of breast cancers have chromosome 17 aneusomy, due to either 17 monosomy (a single copy of chromosome 17) or polysomy (increased copy numbers of chromosome 17). Although HER2 overexpression is an established adverse prognostic factor in breast cancer, the role of unamplified chromosome 17 polysomy is uncertain and there is a paucity of literature on the correlation of chromosome 17 aneusomy with important prognostic and predictive pathologic factors in invasive breast carcinoma. Furthermore, while patients showing HER2 amplification with or without polysomy 17 are treated with trastuzumab with or without other chemotherapy, treatment of patients with unamplified chromosome 17 polysomy is not well defined. Currently most of these patients are treated similar to patients with neither amplification nor 17 polysomy. The aim of this study was to compare some prognostic and predictive factors in invasive breast carcinoma in patients with unamplified chromosome 17 polysomy with that seen in cases with HER2 gene amplification and those with neither amplification or polysomy. We found that invasive breast carcinomas with unamplified chromosome 17 polysomy are associated with several adverse prognostic indicators such as a higher nuclear grade, mitotic activity, Nottingham score, histologic grade, tumor stage, and greater estrogen receptor negativity with a trend towards the amplified group, in contrast to patients with neither amplification or polysomy. Although most patients with unamplified 17 polysomy have a 2+ equivocal score on immunohistochemistry, a minority has a 3+ positive score. An increased adverse role for unamplified polysomy along with 3+ protein expression in some patients supports the idea that these patients should be considered for therapy with trastuzumab and/or anthracyclines.

Stromal PD-L1 Expression Is Associated With Better Disease-Free Survival in Triple-Negative Breast Cancer

OBJECTIVES Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer, and there is no approved targeted therapy. We studied the expression of programmed cell death protein 1 (PD-1) and its ligand (PD-L1) in TNBC. METHODS Full-face sections from 136 TNBC cases without neoadjuvant therapy between 2004 and 2013 were stained and evaluated for immune cell PD-1 staining and stromal or tumoral PD-L1 staining using the H-score (staining percentage × intensity). Nottingham histologic grade, lymphovascular invasion (LVI), mitotic count, and tumor-infiltrating lymphocytes (TILs) were evaluated. Tumor size, lymph node status, Ki-67 score, metastasis, overall survival (OS), and disease-free survival (DFS) were retrieved from medical records. RESULTS Of the 136 TNBC cases, 69 (51%) had any PD-L1 staining and 35 (26%) had PD-L1 staining with an H-score of 5 or more; 117 (86%) had any PD-1 staining and 68 (50%) had PD-1 staining with an H-score of 5 or more. Tumor size and LVI were significantly associated with worse OS and DFS, and TILs and LVI were significantly associated with metastasis in univariate analysis. Stromal PD-L1 expression was significantly associated with better DFS in multivariate analysis. PD-1 expression was not associated with DFS, OS, or metastasis. CONCLUSIONS PD-L1 expression is seen in a high proportion of TNBCs and associated with better DFS.

Limitations of the criteria used to diagnose histologic endometritis in epidemiologic pelvic inflammatory disease research

While endometrial neutrophils and plasma cells are criteria used to diagnose histologic endometritis in epidemiologic pelvic inflammatory disease (PID) research, plasma cell misidentification and nonspecificity may limit the accuracy of these criteria. Herein, we examined: (1) the identification of endometrial plasma cells with conventional methyl green pyronin-based methodology versus plasma cell-specific (CD138) immunostaining, (2) the prevalence of endometrial plasma cells among women at low risk for PID, and (3) endometrial leukocyte subpopulations among women diagnosed with acute or chronic histologic endometritis by conventional criteria. We observed an absence of CD138+ cells in 25% of endometrial biopsies in which plasma cells had been identified by conventional methodology, while additional immunohistochemical analyses revealed indistinguishable inflammatory infiltrates among women diagnosed with acute or chronic endometritis by conventional criteria. Among women considered at lower risk for PID development, flow cytometric analyses detected plasma cells in 30% of endometrial biopsy specimens, suggesting that these cells, even when accurately identified, only nonspecifically identify upper genital tract inflammatory processes. Combined, our findings underscore the limitations of the criteria used to diagnose histologic endometritis in PID-related research and suggest that satisfactory understanding of PID pathogenesis, treatment, and prevention is hindered by continued use of these criteria.

Biomarkers Predicting Pathologic Complete Response to Neoadjuvant Chemotherapy in Breast Cancer

OBJECTIVES Recent studies have shown strong correlation of pathologic complete response (pCR) to neoadjuvant chemotherapy with survival and prognosis in breast cancers. METHODS Clinical data from 237 breast cancer patients who received neoadjuvant chemotherapy between 2012 and 2014 were reviewed. Correlations were sought between pCR and estrogen receptor (ER), progesterone receptor (PR), and HER2 status; Nottingham and nuclear grades; tumor tubule formation; mitotic score; Ki67 index; and tumoral and stromal lymphocytic infiltration (TLI and SLI, respectively). RESULTS Of the 237 cases, 104 (43.9%) achieved pCR. The HER2+ and triple negative breast cancer (TNBC) subtypes had higher pCR rates compared with the luminal subtype (ER+ or PR+ and HER2-). ER and PR negativity, HER2 positivity, Nottingham grade 3, increased TLI and SLI, high mitotic count and Ki67 score correlated significantly with pCR in the overall cohort. TLI and SLI correlated significantly with pCR in the HER2+ and TNBC subtypes in multivariate analysis, whereas no biomarkers correlated with pCR in the luminal subtype. CONCLUSIONS In addition to the pathologic parameters and biomarkers already routinely assessed, evaluation of TLI and SLI may help to better select patients with HER2+ and TNBC for neoadjuvant chemotherapy.

New Developments in Breast Cancer and Their Impact on Daily Practice in Pathology

Advances in research have transformed our understanding of breast cancers and have altered the daily practice of pathology. Theranostic evaluations performed by pathologists are now critical in triaging the patients into appropriate treatment groups, as are new guidelines that were recently established for the evaluation of HER2/neu gene amplification. Emerging molecular classifications of breast cancers bring novel perspectives to the assessment of individual cases, and opportunities for better treatments. Molecular studies have particularly shed light on distinct biological subsets of triple-negative breast cancers, for which new targeted therapies are being developed. The prognostic and therapeutic utility of new histopathologic parameters, such as tumor-infiltrating lymphocytes, are also being elucidated, and new protocols have been devised for the pathologic evaluation of breast specimens that have undergone neoadjuvant treatment. Novel clinical practices, such as radioactive seed localization, also affect the way breast specimens are processed and evaluated. In this brief review, we highlight the developments that are most relevant to pathology and are changing or could potentially impact our daily practice.

Endometrial leukocyte subpopulations associated with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis genital tract infection

OBJECTIVE The objective of the study was to characterize endometrial inflammation associated with common genital tract pathogens. STUDY DESIGN The design of the study was the immunohistochemical characterization of the endometrial leukocyte subpopulations from 37 controls and 45 women infected with Chlamydia trachomatis, Neisseria gonorrhoeae, or Trichomonas vaginalis. RESULTS Compared with uninfected women, endocervical infection with C trachomatis, N gonorrhoeae, or T vaginalis was associated with significant increases in endometrial T cells, B cells, plasma cells, and polymorphonuclear leukocytes. Even more substantial increases in T cell, B cell, and plasma cell numbers were detected among women infected endocervically and endometrially with C trachomatis. CONCLUSION Because lower genital tract C trachomatis, N gonorrhoeae, or T vaginalis infections were associated with comparable increases in the same endometrial leukocyte subpopulations, our results suggest the underappreciated involvement of T vaginalis in upper genital tract inflammatory processes. The more robust inflammatory infiltrate associated with C trachomatis endometrial ascension may offer insight into host inflammatory responses associated with pelvic inflammatory disease development.

Tumor-infiltrating lymphocytes are significantly associated with better overall survival and disease-free survival in triple-negative but not estrogen receptor–positive breast cancers ☆

Correlation between tumor-infiltrating lymphocytes (TILs) and complete pathological response (pCR) in breast cancers in neoadjuvant settings have been reported. In this study, we analyzed the association between TILs and diagnostic and prognostic parameters in estrogen receptor-positive (ER+) and triple-negative breast cancer (TNBC) without neoadjuvant treatments. Three hundred forty-four (344) patients who underwent mastectomy for breast cancer (187 ER+ and 157 TNBC) without neoadjuvant treatments were evaluated. Percentage of overall and peripheral TILs were correlated with lymphovascular invasion (LVI), Nottingham histologic grade (NHG, 1/2 versus 3), stage, lymph node status (LN), overall survival (OS), and disease-free survival (DFS). In TNBC, both peripheral and overall TILs were significantly associated with NHG 3 (P<.0001). Peripheral but not overall TILs were significantly associated with better OS (hazard ratio [HR]: 0.95; 95% confidence interval [CI]: 0.91-1.00; P=.0354) and DFS (HR: 0.95; 95% CI: 0.91-1.00; P=.0314) in univariate and multivariate analysis. In ER+ breast cancer, only peripheral TILs were associated with NHG 3 (P=.018) but not with OS or DFS (both P>.05). In ER+ breast cancer, there was a negative association between Oncotype DX recurrence score and both overall (P=.0007) and peripheral TILs (P=.0119). In conclusion, peripheral but not overall TILs correlate with better OS and DFS in TNBC, indicating the location of TILs may be important in TNBC. The negative association between TILs and Oncotype DX score in ER+ may indicate the possible prognostic value of TILs in ER+ breast cancer.

Hormone Receptor-Positive Breast Cancer Has a Worse Prognosis in Male Than in Female Patients

Introduction Male breast carcinoma (MBC) is treated similarly to female breast carcinoma (FBC), and similar survival rates for both have been assumed. We analyzed prognostic and clinicopathologic features of MBC to determine whether MBC subtypes differ from FBC subtypes. Patients and Methods We reviewed data for 172,847 FBC and 1442 MBC patients from 2010 to 2012 from the National Cancer Institute Surveillance, Epidemiology, and End Results database. Carcinomas were subtyped according to hormone receptor (HR) and HER2 status as HR‐positive (HR+)/HER2−, HR+/HER2+, HR−/HER2+, and HR−/HER2−. Results The overall incidence of MBC in all breast carcinoma cases was 0.8%. MBC was more frequently HR+/HER2− than was FBC (78.3% vs. 67.4%) and less frequently HR−/HER2− (2.1% vs. 10.9%). More MBC was staged as III or IV (24.9% vs. 17.2%). MBC had significantly worse overall survival (OS) than FBC (P < .0001). After adjustment for age, ethnicity, and tumor grade, stage I and II MBC had significantly worse OS time than stage‐matched FBC (P = .0011 for stage I, P = .0229 for stage II). When stage‐ and subtype‐matched patients were compared, MBC had significantly worse OS than FBC for stage I overall, for substages IA and IIB HR+/HER2− carcinoma, and for stage III HR+/HER2+ carcinoma. Furthermore, MBC patients with HR+/HER2− T1aN0 carcinomas had worse OS than did FBC patients. Conclusion Patients with MBC have worse survival than patients with FBC, especially for early‐stage HR+ breast cancers. More studies are needed optimize treatment for MBC. Micro‐Abstract Male breast carcinoma (MBC) has been thought to have similar survival as female breast carcinoma (FBC). We studies 172,847 FBC and 1442 MBC from the SEER data and found patients with MBC have worse survival than patients with FBC.

The value of mutational profiling of the cytocentrifugation supernatant fluid from fine-needle aspiration of pancreatic solid mass lesions.

Fine-needle aspiration (FNA) of pancreatic solid masses can be significantly impacted by sampling variation. Molecular analysis of tumor DNA can be an aid for more definitive diagnosis. The aim of this study was to evaluate how molecular analysis of the cell-free cytocentrifugation supernatant DNA can help reduce sampling variability and increase diagnostic yield. Twenty-three FNA smears from pancreatic solid masses were performed. Remaining aspirates were rinsed for preparation of cytocentrifuged slides or cell blocks. DNA was extracted from supernatant fluid and assessed for DNA quantity spectrophotometrically and for amplifiability by quantitative PCR (qPCR). Supernatants with adequate DNA were analyzed for mutations using PCR/capillary electrophoresis for a broad panel of markers (KRAS point mutation by sequencing, microsatellite fragment analysis for loss of heterozygosity (LOH) of 16 markers at 1p, 3p, 5q, 9p, 10q, 17p, 17q, 21q, and 22q). In selected cases, microdissection of stained cytology smears and/or cytocentrifugation cellular slides were analyzed and compared. In all, 5/23 samples cytologically confirmed as adenocarcinoma showed detectable mutations both in the microdissected slide-based cytology cells and in the cytocentrifugation supernatant. While most mutations detected were present in both microdissected slides and supernatant fluid specimens, the latter showed additional mutations supporting greater sensitivity for detecting relevant DNA damage. Clonality for individual marker mutations was higher in the supernatant fluid than in microdissected cells. Cytocentrifugation supernatant fluid contains levels of amplifiable DNA suitable for mutation detection and characterization. The finding of additional detectable mutations at higher clonality indicates that supernatant fluid may be enriched with tumor DNA. Molecular analysis of the supernatant fluid could serve as an adjunct method to reduce sampling variability and increase diagnostic yield, especially in cases with a high clinical suspicion for malignancy and limited number of atypical cells in the smears.