No abstract

Neuroendocrine carcinoma of the breast is considered a rare entity, and for this reason there are no data from prospective clinical trials on its optimal management. Early stage tumors are usually treated with the same strategy used for the other types of invasive breast cancer. Anthracycline-and taxane-based regimens represent the most frequently administered chemotherapy in neoadjuvant and adjuvant setting, as well as for metastatic disease, although combinations of platinum compounds and etoposide have been widely used, in particular for small-cell histology and tumors with a high proliferation index. For metastatic disease, a multimodality therapeutic strategy can be considered on an individual basis, with chemotherapy, endocrine therapy, peptide receptor radionuclide therapy, radiation therapy, surgery, or a combination of the above. In the near future, a better knowledge of the biology of these tumors will hopefully provide new therapeutic targets for personalized treatment. In this review, we discuss the current evidence and the future perspectives on diagnosis and treatment of neuroendocrine carcinoma of the breast. The Oncologist 2016;21:28-32 Implications for Practice: Neuroendocrine carcinoma of the breast (NECB) is a distinct entity of breast cancer. Clinical features and morphology are not helpful to distinguish NECB from other subtypes of breast cancer; therefore, immunohistochemistry markers for neuroendocrine differentiation, mainly chromogranin and synaptophysin, should be routinely used to confirm the diagnosis, especially in cases of mucinous or solid papillary carcinoma in which the suspicion of NECB may be relevant. Adjuvant treatment should be offered according to the same recommendations given for the other types of invasive breast cancer. An accurate diagnosis of NECB is also important in the metastatic setting, in which a multimodality approach including specific therapies such as peptide receptor radionuclide therapy can be considered.

The clinicopathological features of 56 patients with mucinous cystic tumors (MCTs) of the pancreas were studied. Particular attention was paid to the prognosis of MCTs and the relationship to their ovarian, hepatic, and retroperitoneal counterparts. To distinguish MCTs from pancreatic intraductal papillary-mucinous tumors, MCTs were defined as tumors lacking communication with the duct system and containing mucin-producing epithelium, usually supported by ovarian-like stroma. All 56 tumors occurred in women (mean age 48.2 years) and were preferentially (93%) located in the body and tail of the pancreas. In accordance with the WHO classification, MCTs were divided into adenomas (n = 22), borderline tumors (n= 12), and noninvasive and invasive carcinomas (n = 22). Survival analysis revealed the extent of invasion to be the most significant prognostic factor (p<0.0001). Malignancy correlated with multilocularity and presence of papillary projections or mural nodules, loss of ovarian-like stroma, and p53 immunoreactivity. Stromal luteinization with expression of tyrosine hydroxylase, calretinin, or alpha inhibin was found in 66% of the cases. We conclude that the biologic behavior of MCTs is predictable on the basis of the extent of invasion. The similarities (i.e. gender, morphology, stromal luteinization) between pancreatic MCT and its ovarian, hepatobiliary, and retroperitoneal counterparts suggest a common pathway for their development.

An accurate definition of the criteria to determine the PD-L1 status of a given tumor may greatly help in selecting those patients who could benefit from anti-programmed cell death 1/PD-L1 treatment.

The term diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) may be used to describe a clinico-pathological syndrome, as well as an incidental finding on histological examination, although there are obvious differences between these two scenarios. According to the World Health Organization, the definition of DIPNECH is purely histological. However, DIPNECH encompasses symptomatic patients with airway disease, as well as asymptomatic patients with neuroendocrine cell hyperplasia associated with multiple tumourlets/carcinoid tumours. DIPNECH is also considered a pre-neoplastic lesion in the spectrum of pulmonary neuroendocrine tumours, because it is commonly found in patients with peripheral carcinoid tumours.In this review, we summarise clinical, physiological, radiological and histological features of DIPNECH and critically discuss recently proposed diagnostic criteria. In addition, we propose that the term "DIPNECH syndrome" be used to indicate a sufficiently distinct patient subgroup characterised by respiratory symptoms, airflow obstruction, mosaic attenuation with air trapping on chest imaging and constrictive obliterative bronchiolitis, often with nodular proliferation of neuroendocrine cells with/without tumourlets/carcinoid tumours on histology. Surgical lung biopsy is the diagnostic gold standard. However, in the appropriate clinical and radiological setting, transbronchial lung biopsy may also allow a confident diagnosis of DIPNECH syndrome.

Immunotherapy with checkpoint inhibitors, allowing recovery of effector cells function, has demonstrated to be highly effective in many tumor types and represents a true revolution in oncology. Recently, the anti-PD1 agent pembrolizumab was granted FDA approval for the first line treatment of patients with advanced non–small cell lung cancer (NSCLC) whose tumors show PD-L1 expression in ≥ 50% of neoplastic cells and as a second line treatment for patients with NSCLC expressing PD-L1 in ≥1% of neoplastic cells, evaluated with a validated assay. For the large majority of patients such evaluation is made on small biopsies. However, small tissue samples such as core biopsies might not be representative of tumors and may show divergent results given the possible heterogeneous immunoexpression of the biomarker. We therefore sought to evaluate PD-L1 expression concordance in a cohort of 239 patients using tissue microarrays (TMA) as surrogates of biopsies stained with a validated PD-L1 immunohistochemical assay (SP263) and report the degree of discordance among tissue cores in order to understand how such heterogeneity could affect decisions regarding therapy.We observed a discordance rate of 20% and 7.9% and a Cohen's κ value of 0.53 (moderate) and 0,48 (moderate) for ≥ 1% and ≥ 50% cutoffs, respectively.Our results suggest that caution must be taken when evaluating single biopsies from patients with advanced NSCLC eligible for immunotherapy; moreover, at least 4 biopsies are necessary in order to minimize the risk of tumor misclassification.

The tumor microenvironment (TM) contains a wide variety of cell types and soluble factors capable of suppressing immune responses. While the presence of NK cells in pleural effusions (PE) has been documented, no information exists on the presence of other innate lymphoid cell (ILC) subsets and on the expression of programmed cell death‐1 (PD‐1) in NK and ILC. The presence of ILC was assessed in PE of 54 patients (n = 33 with mesothelioma, n = 15 with adenocarcinoma and n = 6 with inflammatory pleural diseases) by cell staining with suitable antibody combinations and cytofluorimetric analysis. The cytokine production of ILC isolated from both PE and autologous peripheral blood was analyzed upon cell stimulation and intracytoplasmic staining. We show that, in addition to NK cells, also ILC1, ILC2 and ILC3 are present in malignant PE and that the prevalent subset is ILC3. PE‐ILC subsets produced their typical sets of cytokines upon activation. In addition, we analyzed the PD‐1 expression on NK/ILC by multiparametric flow‐cytometric analysis, while the expression of PD‐1 ligand (PD‐L1) was evaluated by immunohistochemical analysis. Both NK cells and ILC3 expressed functional PD‐1, moreover, both tumor samples and malignant PE‐derived tumor cell lines were PD‐L1+ suggesting that the interaction between PD‐1+ILC and PD‐L1+tumor cells may hamper antitumor immune responses mediated by NK and ILC.

Pembrolizumab is the only programmed cell death 1/programmed death-ligand 1 inhibitor for treatment of patients with non-small cell lung cancer, with a companion diagnostic assay, the 22C3 PharmDx. Although in many studies 22C3 and Ventana's SP263 appear to yield overlapping results, they show discrepancies at clinically relevant cutoffs (1% and 50%). We provide a solid comparison between 22C3 and SP263 assays in a large cohort of non-small cell lung cancer cases taking into account interobserver variability between trained pathologists who are used to either clone in their clinical practice. Serial sections of tissue microarrays, built from 198 cases of resected lung cancer, were stained for 22C3 on the Dako Link-48 platform and for SP263 on the Ventana Benchmark Ultra, following manufacturer's instructions. A protocol was also developed to run the 22C3 antibody on the Ventana platform. The pathologist used to 22C3 scored consistently higher than the pathologist used to SP263 at both 1% and 50% cutoff for all assays. For 22C3 and SP263 on respective platforms, we found statistically significant differences in terms of proportion of positive cases at both cutoffs; at 50% cutoff, around half of the cases positive with SP263 would have been defined negative with 22C3 by both pathologists. Important differences were also observed, when comparing clone 22C3 and SP263, both run on the Ventana platform. The lowest differences were seen with 22C3 run on both platforms. Assays 22C3 and SP263 show important discrepancies in identifying programmed death-ligand 1-positive cases at clinically relevant cutoffs, with possible underestimation of patients suitable for pembrolizumab therapy.