Molecular subtyping of mammary-like adenocarcinoma of the vulva shows molecular similarity to breast carcinomas.

AIMS: Mammary-like adenocarcinoma (MLA) of the vulva is thought to be derived from vulvar mammary-like glands. The aim of this study was to characterize a series of MLAs by using an immunohistochemical algorithm that identifies the major molecular subtypes of breast cancer. METHODS AND RESULTS: Seven cases of vulval MLA were stained for oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), Ki67, epidermal growth factor receptor (EGFR), cytokeratin (CK) 5, nestin, and inositol polyphosphate-4-phosphatase (INPP4b). Seventeen cases of vulval extramammary Paget disease (EMPD), seven with invasion, were studied for comparison. The median age of patients with MLA was 72 years. All tumours except one were early-stage tumours. On the basis of an immunohistochemical panel, three of seven tumours were classified as luminal B, two of seven as HER2-enriched, one of seven as luminal A, and one of seven as basal-like. ER was expressed in four of seven tumours, PR in three of seven, HER2 in three of seven, EGFR in two of seven, and CK5 in one of seven, and the Ki67 index was >15% in six of seven cases. Nestin and INPP4b were, respectively, negative and positive in all cases. Of the seven cases of invasive EMPD, two showed a luminal A profile, three a luminal B profile (two of three with HER2 amplification), one a HER2-enriched profile, and one a basal-like profile. Three of seven were HER2-amplified. Among the 10 cases of EMPD without invasion, seven showed a luminal A profile and three showed a luminal B profile (all HER2-amplified); no HER2-enriched or basal-like subtypes were identified. CONCLUSIONS: Breast cancer subtyping can be applied to vulvar MLAs. All four intrinsic molecular subtypes are seen, with frequencies similar to those in breast carcinoma. Our results support the potential use of breast cancer molecular profiling algorithms to guide treatment for these cancers.

Basal biomarkers nestin and INPP4b identify intrinsic subtypes accurately in breast cancers that are weakly positive for oestrogen receptor.

AIMS: Recent evidence indicates that weakly positive immunohistochemical staining of oestrogen receptor (ER) is not associated reliably with a luminal subtype, with the majority reclassified as basal-like by gene expression profile. In this study we assessed the capacity of recently identified immunohistochemical markers of basal-like subtype not dependent upon ER status - positive expression of nestin or loss of inositol polyphosphate-4-phosphatase (INPP4b) - to discriminate intrinsic subtypes, focusing on clinically problematic cases with weak ER positivity. METHODS AND RESULTS: Formalin-fixed paraffin-embedded blocks, enriched for large proportions of ER-negative and ER weakly positive breast cancers, were selected from two previous studies conducted in the period 2008-13 and used for (i) RNA extraction for 50-gene subtype predictor (PAM50) intrinsic subtyping and (ii) tissue microarray construction for immunohistochemical assessment of nestin and INPP4b. Fifty-eight cases were weakly positive for ER (Allred 3-5), among which 28 (48%) were assigned as basal-like by PAM50 gene expression. In these 58 cases, the nestin/INPP4b panel identified 23 basal-like cases with a positive predictive value of 87% [95% confidence interval (CI) 78-95%] and excluded luminal subtype with a negative predictive value of 95% (95% CI 88-100%). Weakly positive ER patients assigned as basal-like by nestin/INPP4b definition demonstrated a median survival time of 45.8 months, significantly lower than 65 months among other ER weakly positive cases (P = 0.012). CONCLUSIONS: Immunohistochemical assessment of nestin and INPP4b provides an accurate, accessible and inexpensive tool to identify basal-like breast cancer subtype in the clinically problematic setting of weak ER positivity. This panel identifies poor prognosis patients who might need strong considerations for non-endocrine-based therapies.

Advances in sarcoma diagnostics and treatment.

The heterogeneity of sarcomas with regard to molecular genesis, histology, clinical characteristics, and response to treatment makes management of these rare yet diverse neoplasms particularly challenging. This review encompasses recent developments in sarcoma diagnostics and treatment, including cytotoxic, targeted, epigenetic, and immune therapy agents. In the past year, groups internationally explored the impact of adding mandatory molecular testing to histological diagnosis, reporting some changes in diagnosis and/or management; however, the impact on outcomes could not be adequately assessed. Transcriptome sequencing techniques have brought forward new diagnostic tools for identifying fusions and/or characterizing unclassified entities. Next-generation sequencing and advanced molecular techniques were also applied to identify potential targets for directed and epigenetic therapy, where preclinical studies reported results for agents active within the receptor tyrosine kinase, mTOR, Notch, Wnt, Hedgehog, Hsp90, and MDM2 signaling networks. At the level of clinical practice, modest developments were seen for some sarcoma subtypes in conventional chemotherapy and in therapies targeting the pathways activated by various receptor tyrosine kinases. In the burgeoning field of immune therapy, sarcoma work is in its infancy; however, elaborate protocols for immune stimulation are being explored, and checkpoint blockade agents advance from preclinical models to clinical studies.

Immune infiltrates in the breast cancer microenvironment: detection, characterization and clinical implication.

Although unlike melanoma, breast cancer is not generally viewed as a highly immunogenic cancer, recent studies have described a rich tumor immune microenvironment in a subset of breast cancers. These immune infiltrates, comprised cells from the innate and adaptive immune response, can be detected and characterized in biopsy specimens and have prognostic value. Tumor-infiltrating lymphocytes (TILs) represent the majority of mononuclear immune infiltrates in the breast tumor microenvironment and can be easily identified in formalin-fixed paraffin-embedded tissues after standard hematoxylin and eosin staining. High levels of TILs are most common in HER2+ and basal-like subtypes where they are associated with good prognosis and with response to certain therapies such as the anti-HER2 antibody trastuzumab. International collaborative efforts are underway to standardize the assessment of TILs so as to facilitate their implementation as a breast cancer biomarker. Using immunohistochemistry to further characterize TILs, recent reports describe the presence of important lymphocyte populations including CD8+ cytotoxic, FOXP3+ regulatory, and CD4+ helper and follicular T cells which have overlapping associations with prognosis and response to therapies. Moreover, recently identified immune checkpoint markers (PD-1, PD-L1) are present in some breast cancers, implying some cases might be especially amenable to immune checkpoint inhibitor treatment strategies which are being evaluated in a number of active clinical trials.

Molecular subtype profiling of invasive breast cancers weakly positive for estrogen receptor.

The estrogen receptor (ER) is a key predictive biomarker in the treatment of breast cancer. There is uncertainty regarding the use of hormonal therapy in the setting of weakly positive ER by immunohistochemistry (IHC). We report intrinsic subtype classification on a cohort of ER weakly positive early-stage breast cancers. Consecutive cases of breast cancer treated by primary surgical resection were retrospectively identified from 4 centers that engage in routine external proficiency testing for breast biomarkers. ER-negative (Allred 0 and 2) and ER weakly positive (Allred 3-5) cases were included. Gene expression profiling was performed using qRT-PCR. Intrinsic subtype prediction was made based upon the PAM50 gene expression signature. 148 cases were included in the series: 60 cases originally diagnosed as ER weakly positive and 88 ER negative. Of the cases originally assessed as ER weakly positive, only 6 (10 %) were confirmed to be of luminal subtype by gene expression profiling; the remaining 90 % of cases were classified as basal-like or HER2-enriched subtypes. This was not significantly different than the fraction of luminal cases identified in the IHC ER-negative cohort (5 (5 %) luminal, 83(95 %) non-luminal). Recurrence-free, and overall, survival rates were similar in both groups (p = 0.4 and 0.5, respectively) despite adjuvant hormonal therapy prescribed in the majority (59 %) of weakly positive ER cases. Weak ER expression by IHC is a poor correlate of luminal subtype in invasive breast cancer. In the setting of highly sensitive and robust IHC methodology, cutoffs for ER status determination and subsequent systemic therapy should be revisited.

Clinical and molecular characteristics of triple-negative breast cancer patients in Northern Israel: single center experience.

INTRODUCTION: Triple-negative breast cancer (TNBC) lacks estrogen and progesterone receptors and does not overexpress HER2. It displays a distinct clinical behavior. This study aims to assess the clinical, molecular and prognostic characteristics of TNBC patients. PATIENTS/METHODS: TNBC patients, referred to a tertiary medical center, 1/1/2000 - 31/12/2005, were included. Clinical, molecular and prognostic characteristics were retrospectively collected from patients' records. RESULTS: Overall, 122 consecutive TNBC patients were included with a median age of 54 years. Among the TNBC patients, 101 (82.8%) were Jews and 21 (17.2%) were Arabs. Family history for breast cancer was reported in 30 patients (24.6%). Genetic counseling was conducted in 30 patients (24.6%); 22/30 (73.3%) had BRCA1/2 mutations. Median tumor size was 2 cm and positive lymph nodes were detected in pathological examination in 40 patients (34%). At the time of data analysis, 21/118 patients (17.8%), who initially presented with early disease, had developed metastasis. Local recurrence was detected in four patients (3.4%). The overall survival (OS) was significantly longer for patients younger than 60 years compared to those ≥ 60 years, (Hazard ratio (HR) =2.1, p=0.046). Nulliparous patients had significantly higher OS than patients with a reproductive history of ≥ 4 children. (HR=0.31, p= 0.041). Mortality rate was higher for Arabs versus Jews but did not reach significance, (HR=1.33; P=0.64). CONCLUSIONS: TNBC represents an exclusive clinical behavior. Older age and parity were found to be poor prognostic factors. Further larger studies are needed to reaffirm our findings and explore the genetics among non-BRCA1/2 TNBC patients.