Comparative immunohistochemical study of the microenvironment of primary mediastinal Β-cell lymphoma and mediastinal nodular sclerosis classic Hodgkin lymphoma

Primary mediastinal B-cell lymphoma (PMBL) and nodular sclerosis classic Hodgkin lymphoma (NSCHL) share common clinical, histological and molecular features which often result in differential diagnosis complications. Given the high importance of the tumor microenvironment (TME) in lymphomas, we aimed to investigate if the aforementioned similarities reflect the cellular composition of their immune milieu as well. Twenty-four mediastinal mass biopsies (12 PMBL cases and 12 NSCHL cases) from previously untreated patients were re-evaluated and examined for the infiltration levels by eosinophils, mast cells, CD4+ T cells, CD8+ T cells and FOXP3+ cells. NSCHL cases were statistically significantly infiltrated in higher levels by all of the examined cells, apart from CD8+ T cells, which were found more abundant in PMBL. Of note, 2 out of 12 PMBL cases presented FOXP3 positivity of the neoplastic cells. The TME of NSCHL was found more abundant and heterogeneous compared to that of PMBL, which should be taken into account in the differential diagnosis. Moreover, FOXP3 scarcity in PMBL suggests different mechanisms for T-cell anergy induction

Morphologic-Molecular Transformation of Oncogene Addicted Non-Small Cell Lung Cancer

Patients with non-small cell lung cancer, especially adenocarcinomas, harbour at least one oncogenic driver mutation that can potentially be a target for therapy. Treatments of these oncogene-addicted tumours, such as the use of tyrosine kinase inhibitors (TKIs) of mutated epidermal growth factor receptor, have dramatically improved the outcome of patients. However, some patients may acquire resistance to treatment early on after starting a targeted therapy. Transformations to other histotypes-small cell lung carcinoma, large cell neuroendocrine carcinoma, squamous cell carcinoma, and sarcomatoid carcinoma-have been increasingly recognised as important mechanisms of resistance and are increasingly becoming a topic of interest for all specialists involved in the diagnosis, management, and care of these patients. This article, after examining the most used TKI agents and their main biological activities, discusses histological and molecular transformations with an up-to-date review of all previous cases published in the field. Liquid biopsy and future research directions are also briefly discussed to offer the reader a complete and up-to-date overview of the topic

Papillary carcinoma arising from the pyramidal lobe of the thyroid gland – Two case reports

The pyramidal lobe (PL) displays variations and is rarely affected by carcinoma. This manuscript presents two such carcinomas.Case 1: Painful mass in the neck, and swallowing difficulty. Echography showed hypoechoic mass, with Bethesda VI cytology. Total thyroidectomy was performed.Case 2: Prominent mass in the neck for 25 years that enlarged. CT revealed a mass in PL. Total thyroidectomy with prophylactic central compartment was performed, followed by bilateral lymph node dissection.Pathology revealed for the first patient two papillary tumors (pyramidal and right lobe) and for the second a papillary tumor with focal extrathyroideal extension (PL) and multiple papillary microcarcinomas. Central compartment had 3 and lateral 5 lymph nodes infiltrated.Although PL is a non-constant anatomic formation, the oncologic principles followed should be the same as in classic thyroid surgery. The central position of PL may be the reason of bilateral lymph node positivity. Keywords: Pyramidal lobe, Papillary carcinoma, Rare thyroid carcinomas, Total thyroidectomy, Thyroid anatomic variation