COVID-19 post-vaccination lymphadenopathy: A review of the use of fine needle aspiration cytology.

COVID-19 vaccine-associated clinical lymphadenopathy (C19-LAP) and subclinical lymphadenopathy (SLDI), which are mainly detected by 18F-FDG PET-CT, have been observed after the introduction of RNA-based vaccines during the pandemic. Lymph node (LN) fine needle aspiration cytology (FNAC) has been used to diagnose single cases or small series of SLDI and C19-LAP. In this review, clinical and LN-FNAC features of SLDI and C19-LAP are reported and compared to non-Covid (NC)-LAP. A search for studies on C19-LAP and SLDI histopathology and cytopathology was performed on PubMed and Google Scholar, on 11 January 2023. Reports on LN-FNAC of C19-LAP were retrieved. A total of 14 reports, plus one unpublished case of C19-LAP observed in our institution, diagnosed by LN-FNAC were included in a pooled analysis and compared to the corresponding histopathological reports. In total, 26 cases were included in this review, with a mean age of 50.5 years. Twenty-one lymphadenopathies assessed by LN-FNAC were diagnosed as benign, and three cases as atypical lymphoid hyperplasia; the latter were subsequently confirmed as benign (one by repetition of LN-FNAC, two by histological control). One case of mediastinal lymphadenopathy in a patient suffering from melanoma was reported as reactive granulomatous inflammation, while one unsuspected case was diagnosed as metastasis from melanoma. In all cases, the cytological diagnoses were confirmed by follow-up or excisional biopsy. The high diagnostic value of LN-FNAC in excluding malignant processes was extremely useful in this context and may be particularly valuable when CNB or histological excisions are difficult to perform, as was the case during Covid lockdowns.

Primary Cutaneous B-Cell Lymphomas with Large Cell Morphology: A Practical Review.

Most primary cutaneous lymphomas consist of T-cell lymphomas or small cell lymphomas; however, the skin may also be affected by lymphomas with large cell morphology, as a primary or secondary localization. A minority of cases consist of primary cutaneous B-cell lymphomas (PCBCLs). PCBCLs are a heterogeneous group of rare neoplasms with an overlapping morphological and immunohistochemical picture of the different subtypes. Nevertheless, differential diagnosis in the setting of this group of neoplasms is mandatory to identify the correct therapy and prognosis, but it may be challenging since, due to the rarity of these neoplasms, they may not always be familiar to pathologists. Indeed, immunohistochemistry may not be enough to distinguish the different histotypes, which overlap in immunohistochemical features. Furthermore, the ever-increasing knowledge of the molecular features of systemic B-cell lymphomas, such as gene rearrangements with clinical significance, has led in recent years to further investigation into the molecular landscape of PCBCLs with large cell morphology. This work aimed to provide a practical diagnostic guide for pathologists dealing with primary cutaneous large B-cell lymphomas.

Current and potential immunohistochemical biomarkers for prognosis and therapeutic stratification of breast carcinoma.

The identification of biomarkers on cancer tissue samples could be obtained through several technologies. In this setting, the immunohistochemistry and in situ hybridization are accessible in most pathology laboratories. Particularly, immunohistochemistry can be used not only for diagnostic issues, but also to define prognostic classes and to define response to specific therapies. Particularly the last applications have been firstly developed in the breast cancer pathology. In addition, the development of molecular classification proposed some prognostic/predictive classes that could be easily defined by immunohistochemistry. Thus, the role of the pathologists has become increasingly important in the definition of prognosis and in the choice therapy, because the immunohistochemical biomarkers are used to guide treatment, to classify breast cancer into biologically and prognostically distinct subtypes. In this review, we will provide information on the current application of the immunohistochemical biomarkers useful in the management of breast cancer patients. Moreover, we consider the application of immunohistochemistry in the definition of the most promising biomarkers derived from molecular studies of the breast cancer, that in the future could integrate the characterization of breast cancer into clinical practice.

Triple blockade of Ido-1, PD-L1 and MEK as a potential therapeutic strategy in NSCLC.

BACKGROUND: Despite the recent progress in the treatment and outcome of Non Small Cell Lung Cancer (NSCLC), immunotherapy has still significant limitations reporting a significant proportion of patients not benefiting from therapy, even in patients with high PD-L1 expression. We have previously demonstrated that the combined inhibition of MEK and PD-L1 in NSCLC patients derived three dimensional cultures exerted significant synergistic effect in terms of immune-dependent cancer cell death. However, subsequent experiments analyzing the expression of Indoleamine 2,3-dioxygenase-1 (Ido-1) gene expression demonstrated that Ido-1 resulted unaffected by the MEK inhibition and even increased after the combined inhibition of MEK and PD-L1 thus representing a potential escape mechanism to this combination. METHODS: We analyzed transcriptomic profile of NSCLC lung adenocarcinoma cohort of TCGA (The Cancer Genome Atlas), stratifying tumors based on EMT (Epithelial mesenchymal Transition) score; in parallel, we investigated the activation of Ido-1 pathway and modulation of immune cytokines productions both in NSCLC cells lines, in peripheral blood mononuclear cells (PBMCs) and in ex-vivo NSCLC spheroids induced by triple inhibition with an anti-PD-L1 monoclonal antibody, the MEK inhibitor and the Ido-1 inhibitor. RESULTS: In NSCLC lung adenocarcinoma patient cohort (from TCGA) Ido-1 gene expression was significantly higher in samples classified as mesenchymal according EMT score. Similarly, on a selected panel of NSCLC cell lines higher expression of MEK and Ido-1 related genes was detected in cells with mesenchymal phenotype according EMT score, thus suggesting a potential correlation of co-activation of these two pathways in the context of EMT, with cancer cells sustaining an immune-suppressive microenvironment. While exerting an antitumor activity, the dual blockade of MEK and PD-L1 enhances the secretion of pro-inflammatory cytokines (IFNγ, TNFα, IL-12 and IL-6) and, consequently, the expression of new immune checkpoints such as Ido-1. The triple inhibition with an anti-PD-L1 monoclonal antibody, the MEK inhibitor and the Ido-1 inhibitor demonstrated significant antiproliferative and proapoptotic activity on ex-vivo NSCLC samples; at the same time the triple combination kept increased the levels of pro-inflammatory cytokines produced by both PBMCs and tumor spheroids in order to sustain the immune response and simultaneously decreased the expression of other checkpoint (such as CTLA-4, Ido-1 and TIM-3) thus promoting an immune-reactive and inflamed micro-environment. CONCLUSIONS: We show that Ido-1 activation is a possible escape mechanism to immune-mediated cell death induced by combination of PD-L1 and MEK inhibitors: also, we show that triple combination of anti-PD-L1, anti-MEK and anti-Ido-1 drugs may overcome this negative feedback and restore anti-tumor immune response in NSCLC patients' derived three dimensional cultures.

Myoepithelial sialadenitis with metachromatic matrix: A diagnostic pitfall. A case of salivary gland swelling in a paediatric patient evaluated by fine needle aspiration cytology.

Fine needle aspiration cytology (FNAC) is generally characterized by a high diagnostic accuracy in differentiating non-neoplastic/inflammatory lesions from neoplastic lesions of the salivary glands. Lymphoepithelial sialadenitis/myoepithelial sialadenitis is exceedingly rare in paediatric patients and is characterized by a diffuse, often bilateral, salivary gland enlargement and the differential diagnosis may sometimes be difficult. We report the case of a 10-year-old boy who presented with a swelling of the left parotid gland investigated by ultrasound salivary gland FNAC.

Atypical cytological presentation of granular cell tumour: Tumour-associated fibrosis may affect fine-needle aspiration cytology accuracy.

The cytological features of granular cell tumour (GCT) are generally quite typical but, in some cases, the fine needle aspiration cytology (FNAC) diagnosis of GCT may be difficult or impossible because of unusual sites of onset or equivocal cytological features. In this report, two GCTs with atypical FNAC features are described in order to investigate the causes and provide possible diagnostic tips. From a series of nine histologically proven GCTs, two inconclusive FNAC cases were retrieved. Smears were poorly cellular showing isolated naked nuclei, anisonucleosis, granular chromatin and occasional small nucleoli. The background was finely granular in one case. Histological controls of these cases revealed marked fibrosis. Tumour-associated fibrosis in GCT is variable and does not seem to influence clinical behaviour but it influences the harvest and the integrity of granular cells collected by FNAC. When GCT smears are poorly cellular, attention should be paid to the granular background and to the few granular cells, if any, as they might be the only features to suggest a GCT.

Interventional cytopathology in the COVID-19 era.

INTRODUCTION: The dramatic spread of COVID-19 has raised many questions about cytological procedures performed in and out of the laboratories all over the world. METHODS: We report a heterogeneous series of fine needle aspirations performed during the period of phase 1 of the lockdown for the COVID-19 pandemic to describe our experience and measures taken during this period. RESULTS: A total of 48 fine needle aspirations (ultrasound, computed tomography and endoscopic ultrasound guided) were processed and reported. CONCLUSIONS: Pre-existing procedures have been modified to allow healthcare professionals to work safely ensuring patients the necessary assistance with samples suitable for cellularity, fixation and staining for an accurate cytological diagnosis.

Primary and secondary cutaneous angiosarcoma: Distinctive clinical, pathological and molecular features.

Angiosarcomas are ubiquitous neoplasms involving both cutaneous and soft tissue and visceral locations. Accumulating biomolecular evidences suggest that cutaneous angiosarcomas are distinctive entities with molecular, clinical and pathological peculiarities. Despite several ongoing clinical trials with promising therapeutic agents, the prognosis of cutaneous angiosarcomas is dismal and survival still rely on early diagnosis and surgery. An accurate diagnosis and the knowledge of the underlying molecular landscape are therefore essential to improve the prognosis. We detail the molecular, clinical, dermoscopic, morphological and prognostic features of cutaneous angiosarcoma. Although the molecular landscape of cutaneous angiosarcoma is not completely understood, accumulating evidences suggest that there are characteristic molecular alterations including dysregulation of angiogenesis and several complex molecular pathways. Secondary cutaneous angiosarcomas, arising in correlation with chronic lymphedema and ionizing radiation, have different molecular hallmarks, which are also leading to the first diagnostic applications. The diagnosis of cutaneous angiosarcoma may be challenging, as well-differentiated forms can be hard to distinguish from benign and low-grade vascular neoplasms, while poorly differentiated forms can be easily confounded with other non-vascular high-grade neoplasms. An accurate and early diagnosis, which is mandatory to ensure the best survival for the patients, is mainly based on morphological hallmarks.

NTRK Fusions, from the Diagnostic Algorithm to Innovative Treatment in the Era of Precision Medicine.

In the era of precision medicine, the identification of several predictive biomarkers and the development of innovative therapies have dramatically increased the request of tests to identify specific targets on cytological or histological samples, revolutionizing the management of the tumoral biomaterials. The Food and Drug Administration (FDA) has recently approved a selective neurotrophic tyrosine receptor kinase (NTRK) inhibitor, larotrectinib. Contemporarily, the development of multi-kinase inhibitors with activity in tumors carrying TRK fusions is ongoing. Chromosomal translocations involving the NTRK1, NTRK2, and NTRK3 genes result in constitutive activation and aberrant expression of TRK kinases in numerous cancer types. In this context, the identification of tumors harboring TRK fusions is crucial. Several methods of detection are currently available. We revise the advantages and disadvantages of different techniques used for identifying TRK alterations, including immunohistochemistry, fluorescence in situ hybridization, reverse transcriptase polymerase chain reaction, and next generation sequencing-based approaches. Finally, we propose a diagnostic algorithm based on histology and the relative frequency of TRK fusions in each specific tumor, considering also the economic feasibility in the clinical practice.

Medullary thyroid carcinoma with double negative calcitonin and CEA: a case report and update of literature review.

BACKGROUND: Medullary thyroid carcinoma is a malignant uncommon and aggressive tumour of the parafollicular C cells. In about 75% of cases it is sporadic while, in case of RET mutation, it is associated to multiple endocrine neoplasia type 2 (25% of cases). The biochemical features of medullary thyroid carcinoma include the production of calcitonin and carcinoembryogenic antigen. The above-mentioned features are useful in the diagnostic process as well as in the follow up and in the prognostication of the disease. Even if calcitonin elevation is strongly associated to MTC, it can also be found increased in many pathological different conditions as pregnancy, lactation, C-cells hyperplasia, autoimmune thyroiditis, end stage renal disease, lung and prostate cancer and several neuroendocrine tumours. Major medullary thyroid tumours are usually connected to high doses of circulating calcitonin, in fact non-secretory variants have hardly been described. CASE PRESENTATION: We herein report the case of a 59 years old male, who had undergone total thyroidectomy for multinodular goiter with negative preoperative calcitonin, showing medullary thyroid carcinoma at definitive pathology. To the best of our knowledge, this is the first case documenting a non-secretory medullary thyroid carcinoma, with double negative markers at the time of diagnosis and at the relapse. CONCLUSION: A Literature review underlining pathological hypothesis, differential diagnosis and alternative and innovative biomarkers to identify non-secretory medullary thyroid carcinoma was carried out.

Molecular heterogeneity in lung cancer: from mechanisms of origin to clinical implications.

Molecular heterogeneity is a frequent event in cancer responsible of several critical issues in diagnosis and treatment of oncologic patients. Lung tumours are characterized by high degree of molecular heterogeneity associated to different mechanisms of origin including genetic, epigenetic and non-genetic source. In this review, we provide an overview of recognized mechanisms underlying molecular heterogeneity in lung cancer, including epigenetic mechanisms, mutant allele specific imbalance, genomic instability, chromosomal aberrations, tumor mutational burden, somatic mutations. We focus on the role of spatial and temporal molecular heterogeneity involved in therapeutic implications in lung cancer patients.

Management of cytologic material, preanalytic procedures and biobanking in lymph node cytopathology.

The range of pathologies that lymph node (LN) fine needle cytology (FNC) may encounter is extremely wide and ancillary techniques, in addition to traditional smears, are generally required to reach reliable cytologic diagnoses. Storing part of the cytologic material may be useful or necessary for molecular testing. The main difficulties concern the generally small size of the sample and the different methods of acquisition of LN-FNC. Therefore, the preanalytic phase is extremely important for LN-FNC. This article outlines the management of LN-FNC material, vials, technical devices (e.g.: additional smears, cytospin slides, LBC slides, cards, resins, etc.) and main ancillary techniques to assess their optimal application, taking into account the different diagnostic needs and cell storage.

Lymph node fine-needle cytology in the era of personalised medicine. Is there a role?

The 2016 World Health Organisation revised classification of lymphoma has sub-classified well-defined entities and added a number of provisional entities on the basis of new knowledge on genetic, epigenetics and phenotypical data; prognostic and predictive features are also part of this classification. New knowledge on well-defined entities further enlightens the mechanisms of lymphomagenesis, which are more complex and multifactorial than once believed. Therapies are also more complex because traditional clinical trials have been integrated with new drugs and compounds with unique mechanisms of actions against distinct molecular targets. As lymphoma acquires additional genetic and phenotypic features over the time, pathological assessment is also necessary. Histological evaluation and tissue collection by surgical biopsies are necessary for phenotypical and molecular purposes; however, these are demanding procedures for both the patient and the health care system. At the same time, the choice of the best treatment for a specific entity, in different phases and different patients requires information that may not be available when the biopsy is performed. Fine needle aspiration cytology (FNAC) is successfully used in lymph nodes (LNs) in combination with different ancillary techniques and might be used to assess the phenotypic and genetic profile of specific targets and to get key information for therapy, in different phases and stages of the disease, with the option to re-check the same target over time, without surgical excision. This brief review describes LN-FNAC diagnostic criteria, current therapies for lymphomas and the potential role of LN-FNAC in selecting non-Hodgkin lymphomas patients for specific targeted treatments.

It is no longer the time to disregard thyroid metastases from breast cancer: a case report and review of the literature.

BACKGROUND: Metastases to the thyroid gland are more frequent than previously thought, although most of them are occult or not clinically relevant. Overall, only 42 cases of metastases to thyroid from breast cancer have been reported thus far. Here we report the case of a patient with breast cancer metastatic to the thyroid. We also review the 42 previously reported cases (published between 1962 and 2012). This is the first review about metastases to thyroid gland from breast cancer. CASE PRESENTATION: A 64-year-old woman of Caucasian origin was diagnosed with a lobular invasive carcinoma of the breast (luminal A, stage II). She received adjuvant chemotherapy, followed by endocrine therapy. During follow-up, fine-needle cytology of a thyroid nodule revealed malignant cells that were estrogen-positive, which suggested a diagnosis of metastases to the thyroid. Imaging did not reveal any other metastatic site and showed only enlargement of the left thyroid lobe and an inhomogeneous pattern of colloid and cystic degeneration and calcifications. The patient underwent left hemithyroidectomy. Histology of thyroid tissue showed a colloid goitre containing dispersed small atypical neoplastic cells with eccentric nuclei. Immunohistochemistry showed cytokeratin-19 and oestrogen receptor, but not tireoglobulin, e-cadherin or cytokeratin-7, thereby confirming metastases from a lobular breast carcinoma. Hormonal treatment is ongoing. CONCLUSION: This case report and first review of the literature on metastases to thyroid from breast cancer highlight the importance of a correct early diagnostic work-up in such cases. Indeed, a primary lesion should be distinguished from metastases given the different treatment protocol related to primary cancer and the clinical impact on prognosis.

Extrapleural solitary fibrous tumor: A distinct entity from pleural solitary fibrous tumor. An update on clinical, molecular and diagnostic features.

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm that was originally described to be localized in the pleura, but thereafter, this has been reported in several anatomic sites. Although the etiology of the neoplasm remains largely unknown, the pathogenesis seems to be related to an NAB2-STAT6 fusion gene due to paracentric inversion on chromosome 12q13. The diagnosis of extrapleural SFT is challenging, owing to its rarity, and requires an integrated approach that includes specific clinical, histological, immunohistochemical, and even molecular findings. Histologically, extrapleural SFT shares morphological features same as those of the pleural SFT because it is characterized by a patternless distribution of both oval- and spindle-shaped cells in a variable collagen stroma. In addition, morphological variants of mixoid, fat-forming, and giant cell-rich tumors are described. A correct diagnosis is mandatory for a proper therapy and management of the patients with extrapleural SFT, as extrapleural SFT is usually more aggressive than pleural form, particularly cases occurring in the mediastinum, retroperitoneum, pelvis, and meninges. Although SFT is usually considered as a clinically indolent neoplasm, the prognosis is substantially unpredictable and only partially related to morphological features. In this context, cellularity, neoplastic borders, cellular atypias, and mitotic activity can show a wide range of variability. We review extrapleural SFT by discussing diagnostic clues, differential diagnosis, recent molecular findings, and prognostic factors.

Multidisciplinary Diagnostic and Surgical Management of Adenocarcinoma Gingival Metastases.

Colon cancer is the third leading cause of cancer-related mortality worldwide and colon cancer metastases in rare sites, such as the oral cavity, lead to a worse prognosis. Oral metastasis is a rare clinical condition and it represents only the 1% among all oral cavity neoplasms. A multidisciplinary approach is recommended to carry out a correct diagnostic procedure that allows distinguishing between metastatic and primitive lesions of the oral cavity. Quick diagnosis and management are fundamental to take an appropriate action as early as possible, as usually the prognosis in patients with oral metastases of colon carcinoma is poor. Aim of this brief clinical report is to underline how the quick diagnosis and management of gingival lesions can be crucial for the correct management of those uncommon oral diseases and for having a better prognosis of the primary cancer.

Lymph node fine needle cytology in the staging and follow-up of cutaneous lymphomas.

BACKGROUND: Lymph nodal involvement is an important clinical-pathological sign in primary cutaneous lymphoma (PCL), as it marks the transformation/evolution of the disease from localized to systemic; therefore the surveillance of lymph nodes is important in the staging and follow up of PCL. Fine needle cytology (FNC) is widely used in the diagnosis of lymphadenopathies but has rarely been reported in PCL staging and follow-up. In this study an experience on reactive and neoplastic lymphadenopathies arisen in PCL and investigated by FNC, combined to ancillary techniques, is reported. METHODS: Twenty-one lymph node FNC from as many PCL patients were retrieved; 17 patients had mycosis fungoides (MF) and 4 a primary cutaneous B-cell lymphoma (PBL). In all cases, rapid on site evaluation (ROSE) was performed and additional passes were used to perform flow cytometry (FC), immunocytochemistry (ICC) and/or polymerase chain reaction (PCR) to assess or rule out a possible clonality of the corresponding cell populations. RESULTS: FNC combined with FC, ICC, and PCR identified 12 cases of reactive, non specific, hyperplasia (BRH), 4 dermatopathic lymphadenopathy (DL), 4 lymph nodal involvement by MF and 1 lymph nodal involvement by cutaneous B-cell lymphoma. CONCLUSIONS: FNC coupled with ancillary techniques is an effective tool to evaluate lymph node status in PCL patients, provided that ROSE and a rational usage of ancillary techniques is performed according to the clinical context and the available material. The method can be reasonably used as first line procedure in PCL staging and follow up, avoiding expensive and often ill tolerated biopsies when not strictly needed.

Ultrasound-guided fine needle aspiration cytology of a primary lymph node leiomyoma: a flexible procedure for a complex case.

BACKGROUND: A primary lymph node leiomyoma diagnosed by fine needle aspiration cytology (FNAC) is reported. CASE: A 22-year-old male complained of right groin swelling; ultrasound examination (US) showed a lymph node containing a 20-mm hypoechoic nodule. The residual lymph node was oval, with a well-characterized cortex and hilum. US-FNAC of the nodule showed oval spindle cells embedded in fibrillar matrix. Nuclei were naked and oval with dispersed chromatin but without nucleoli. Immunocytochemistry showed positivity for vimentin and actin, and negativity for cytokeratin, S100, CD23 and CD31. A smear of the residual lymph node showed a reactive lymphoid cell population. FNAC diagnosis was mesenchymal cell proliferation with smooth muscle phenotype; a lymph node is part of the lesion. A CT scan did not detect any inguinal or abdominal mass. The surgical sample was a lymph node containing a spindle cell tumor, which was actin and desmin positive, and S100, CD21, HMB45, CD23 and CD31 negative; MIB1 was positive in <5% of the cells. The residual lymph node was normal. CONCLUSION: The final diagnosis was primary benign leiomyoma in a lymph node. US-FNAC may frame complex lymph node lesions and provide treatment options.