Tumor-associated microenvironment, PD-L1 expression and their relationship with immunotherapy in glioblastoma, IDH-wild type: A comprehensive review with emphasis on the implications for neuropathologists

Although novel knowledge has been acquired on the molecular landscape of glioblastoma (GBM), a relatively few steps forward have been made regarding its therapy. With the increasing use of novel immunotherapeutic drugs capable of stimulating the antitumor inflammatory response, in the last decades numerous studies aimed to characterize the tumor-associated microenvironment (TME) and its relationship with the immunogenicity of GBM. In this regard, although the tumor-associated microglia and macrophages (TAMs) and PD-L1/PD-1 axis have been emerged as one of the most relevant components of the GBM TME and one of the potential molecular pathways targetable with immunotherapy, respectively. It has been supposed that TAMs may acquire different phenotypes, switching from M1 to M2 phenotypes, with tumor-suppressive and tumor-stimulating role depending on the different surrounding conditions. PD-L1 is a type 1 transmembrane protein ligand expressed by T-cells, B-cells and antigen-presenting cells, with a main inhibitory checkpoint role on tumor immune regulation. While PD-L1 immunohistochemical expression has been extensively investigated in many cancers, its usefulness in the evaluation of GBM response rates to immunotherapy and its standardized evaluation by immunohistochemistry are still debated. The present review paper focuses on the current "state of the art" about the relationship between TME, PD-L1/PD-1 pathway and immunotherapy in GBM, also providing neuropathologists with an updated guide about the clinical trials conducted with PD-L1 and PD-1 inhibitors.

Brain Metastases from Breast Cancer Histologically Exhibit Solid Growth Pattern with at Least Focal Comedonecrosis: A Histopathologic Study on a Monocentric Series of 30 Cases

Since there are no morphological clues capable of making a pathologist suspect a possible mammary origin of a metastatic lesion without adequate clinical information, the histologic diagnosis of brain metastasis from BC is still based on the immunohistochemical expression of mammary gland markers such as GATA-3, ERs, PgRs and HER-2. The present retrospective study aimed to select purely morphological features capable of suggesting the mammary origin of a metastatic carcinoma in the brain. The following histological features were collected from a series of 30 cases of brain metastases from breast cancer: (i) a solid growth pattern; (ii) the presence of comedonecrosis; and (iii) glandular differentiation. Our results showed that most cases histologically exhibited a solid growth pattern with at least focal comedonecrosis, producing an overall morphology closely reminiscent of mammary high-grade ductal carcinoma in situ. Although the above-mentioned morphological parameters are not strictly specific to a mammary origin, they may have an important diagnostic utility for leading pathologists to suspect a possible breast primary tumor and to include GATA-3, ERs, PgRs and HER-2 in the immunohistochemical panel.

Tumor Infiltrating Lymphocytes (TILS) and PD-L1 Expression in Breast Cancer: A Review of Current Evidence and Prognostic Implications from Pathologist's Perspective

With the rise of novel immunotherapies able to stimulate the antitumor immune response, increasing literature concerning the immunogenicity of breast cancer has been published in recent years. Numerous clinical studies have been conducted in order to identify novel biomarkers that could reflect the immunogenicity of BC and predict response to immunotherapy. In this regard, TILs have emerged as an important immunological biomarker related to the antitumor immune response in BC. TILs are more frequently observed in triple-negative breast cancer and HER2+ subtypes, where increased TIL levels have been linked to a better response to neoadjuvant chemotherapy and improved survival. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes, and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in breast cancer is observed in about 10-30% of cases and is extremely variable based on tumor stage and molecular subtypes. Briefly, TNBC shows the highest percentage of PD-L1 positivity, followed by HER2+ tumors. On the other hand, PD-L1 is rarely expressed (0-10% of cases) in hormone-receptor-positive BC. The prognostic role of PD-L1 expression in BC is still controversial since different immunohistochemistry (IHC) clones, cut-off points, and scoring systems have been utilized across published studies. In the present paper, an extensive review of the current knowledge of the immune landscape of BC is provided. TILS and PD-L1 expression across different BC subtypes are discussed, providing a guide for their pathological assessment and reporting.

Eosinophilic Angiocentric Fibrosis of the Nasal Cavities: A Report of an Uncommon Lesion with Emphasis on the Etiology and Differential Diagnosis

Background and Objectives: Eosinophilic angiocentric fibrosis (EAF) is an indolent but sometimes locally destructive lesion with a predilection for the sinonasal tract. Although it was first described in 1983, its etiology remains unknown. Some authors initially attributed EAF to trauma, hypersensitivity, and/or surgical manipulation, while it has been recently suggested to include EAF within the spectrum of IgG4-related systemic diseases. Materials and Methods: We report an uncommon case of idiopathic EAF in a 76-year-old male who developed two bilateral tumefactive masses in the nasal cavities. Results: As the histological examination showed a subepithelial proliferation of fibroblasts along with sclero-hyaline fibrosis around small-sized vessels (an “onion skin-like” pattern) and an eosinophils-rich inflammatory infiltrate, a diagnosis of EAF was rendered. The differential diagnosis included granuloma faciale, Wegener’s granulomatosis, and Churg–Strauss syndrome. Conclusions: Pathologists should be aware of the possibility that this lesion can be part of the wide spectrum of IgG4-related systemic diseases by performing IgG4 investigations to assess adherence to IgG4-related systemic disease criteria.

Pathogens Detection in the Small Hive Beetle (Aethina tumida (Coleoptera: Nitidulidae))

Aethina tumida Murray is currently a worldwide emergent pest of Apis mellifera L. hives. Although the damaging effect on the colony stores and brood is well known, the possible role of these beetles as a disease carrier is not clear. This is the first report of DNA presence of the trypanosome honeybee parasite Lotmaria passim and Crithidia bombi, and the Apis mellifera filamentous virus (AmFV) in A. tumida. Further studies will be needed to determine if A. tumida is indeed a mechanical or biological vector of these pathogens.

Peritoneal dialysis: a case for home visits

Peritoneal dialysis (PD) training usually takes place within the dialysis unit. Home visits, however, provide an ideal way for the dialysis team to assess and observe the implementation of the training objectives and to uphold the continuation of care between the dialysis unit and the home. This article describes the benefits and limitations of performing home visits as well as practical guidelines, including the use of an assessment record to document the home visit.

Comparison of the attitudes of Israeli therapists and lay persons to ethical dilemmas in psychotherapy

The issues of confidentiality and boundaries cause ethical dilemmas for psychotherapists. We investigated whether therapists have ethical attitudes to confidentiality and boundaries that are unique to their professional group compared with lay persons and whether gender or professional characteristics are associated with these attitudes. Clinical vignettes capturing ethical dilemmas regarding confidentiality and boundaries were presented to 93 psychotherapists of different professional backgrounds (professional group) and 55 staff and students from the fields of law and the humanities (lay group). In general, the lay group showed a greater tendency to maintain confidentiality than the professional group. Regarding boundaries, the majority of psychotherapists were against initiating any sexual relationship with current patients, former patients, students, or supervisees; the differences between the groups in this area were statistically significant. The vast majority of therapists (96.7%) disapproved of accepting money in advance compared with only 54.4% of the lay group. Analysis of the psychotherapists by professional background revealed that for the majority of the vignettes, there was no difference in attitude to confidentiality and boundaries between psychiatrists, psychologists, and social workers. The present study shows that therapists have different ethical codes from nontherapists regarding the issues of boundaries and the treatment contract. Therapists are stricter than nontherapists regarding issues of boundaries but less strict regarding issues of confidentiality, and there are some minor differences in the attitudes to these issues among different types of therapists.

Induction of estrus in bitches with normal and persistent anestrus using human menopausal gonadotropin (hMG)

Human menopausal gonadotropin (hMG) was administered intramuscularly to 10 bitches during apparently normal anestrus (n = 7) or persistent anestrus (n = 3). Each dog received a 75-IU dose of hMG (75 IU LH and 75 IU FSH; 1 to 7 units/kg) daily for nine days. Nine bitches responded with obvious signs of proestrus within 3 to 9 days. Of these, 3 bitches exhibited a weak proestrus while 2 exhibited a normal estrus and ovulation but failed to become pregnant The remaining 4 bitches became pregnant at the induced cycle and produced normal litters at 72 to 85 d after the start of treatment, including 1 bitch that had been treated at 24 mo after the last estrus. In 2 cases, treatment resulted in ovulation following 25 or 34 mo of chronic pubertal anestrus, 1 of which became pregnant. The results suggest that hMG can be a useful gonadotropin preparation for inducing estrus in dogs.

Ornithine decarboxylase inhibitors and fetal growth retardation in mice

Putrescine (PUT) and the putrescine analogues, 1,3-diaminopropane (DAP) and 1,6-diaminohexane (DAH), were administered to pregnant female mice during the time of maximal fetal ornithine decarboxylase (ODC) activity, days 10-14 of gestation. Such treatment resulted in an inhibition of fetal ODC activity, as measured 2 hours later, and a proportional decrease in fetal weight, as measured on day 18 of gestation. The order of effectiveness for these compounds was DAP greater than DAH greater than PUT. Neither DAP nor DAH nor PUT were fetocidal nor maternally lethal under the treatment regimen employed. The generality of the effect of these compounds, i.e., the retardation of fetal growth and the lack of gross malformations, is consistent with the hypothesis that they are interfering with a primary process, probably protein synthesis. The restricted time span of effectiveness implies that these compounds are specific inhibitors of ODC and that decreased ODC activity is producing an effect on growth.

Anaesthesia and Huntington's chorea. A report of two cases

Two patients with Huntington's chorea were anaesthetized successfully with a technique including thiopentone, nitrous oxide and either a narcotic analgesic or halothane; pancuronium was employed for myoneural blockade.