Male Breast Imaging Uncovers Lymphoma.

Background: A 36-year-old man presented with a palpable mass in the right axillary tail for four months. He was referred to breast imaging for diagnostic work-up. He does not have a family history of breast cancer. Aim: Breast imaging work-up for diagnosis of lymphoma is unusual and even more so in a male patient. Case presentation: After Breast Mammography and targeted Ultrasound of the axillary tail and axilla, Magnetic Resonance Imaging (MRI) was performed and suggested lymphoproliferative disorder. Excisional biopsy was performed after the breast MRI with removal of right axillary tissue measuring 15.0 × 5.5 × 2.0 cm and containing multiple lymph nodes. Excisional biopsy revealed Classic Hodgkin lymphoma of nodular sclerosis type. Staging [18F]-FDG PET/CT revealed early stage of disease. Conclusion: The presentation and diagnostic elements of Hodgkin Lymphoma are described in this case report emphasizing the significance of breast imaging in multiple populations.

Bilateral breast Rosai-Dorfman disease screen detected by mammography.

Rosai-Dorfman disease (RDD) is a proliferative disorder of histiocytes typically found in nodal sites and commonly observed in females. Patients often present with systemic symptoms such as fever, lymphadenopathy, and weight loss. However, extra-nodal disease has been identified in locations including the skin and subcutaneous tissue. We present a case of a 59-year-old female presenting with abnormal bilateral findings on screening mammography, who was found to have a rare presentation of Rosai-Dorfman disease.

Succinate Mediates Tumorigenic Effects via Succinate Receptor 1: Potential for New Targeted Treatment Strategies in Succinate Dehydrogenase Deficient Paragangliomas.

Paragangliomas and pheochromocytomas (PPGLs) are chromaffin tumors associated with severe catecholamine-induced morbidities. Surgical removal is often curative. However, complete resection may not be an option for patients with succinate dehydrogenase subunit A-D (SDHx) mutations. SDHx mutations are associated with a high risk for multiple recurrent, and metastatic PPGLs. Treatment options in these cases are limited and prognosis is dismal once metastases are present. Identification of new therapeutic targets and candidate drugs is thus urgently needed. Previously, we showed elevated expression of succinate receptor 1 (SUCNR1) in SDHB PPGLs and SDHD head and neck paragangliomas. Its ligand succinate has been reported to accumulate due to SDHx mutations. We thus hypothesize that autocrine stimulation of SUCNR1 plays a role in the pathogenesis of SDHx mutation-derived PPGLs. We confirmed elevated SUCNR1 expression in SDHx PPGLs and after SDHB knockout in progenitor cells derived from a human pheochromocytoma (hPheo1). Succinate significantly increased viability of SUCNR1-transfected PC12 and ERK pathway signaling compared to control cells. Candidate SUCNR1 inhibitors successfully reversed proliferative effects of succinate. Our data reveal an unrecognized oncometabolic function of succinate in SDHx PPGLs, providing a growth advantage via SUCNR1.

The Significant Reduction or Complete Eradication of Subcutaneous and Metastatic Lesions in a Pheochromocytoma Mouse Model after Immunotherapy Using Mannan-BAM, TLR Ligands, and Anti-CD40.

Therapeutic options for metastatic pheochromocytoma/paraganglioma (PHEO/PGL) are limited. Here, we tested an immunotherapeutic approach based on intratumoral injections of mannan-BAM with toll-like receptor ligands into subcutaneous PHEO in a mouse model. This therapy elicited a strong innate immunity-mediated antitumor response and resulted in a significantly lower PHEO volume compared to the phosphate buffered saline (PBS)-treated group and in a significant improvement in mice survival. The cytotoxic effect of neutrophils, as innate immune cells predominantly infiltrating treated tumors, was verified in vitro. Moreover, the combination of mannan-BAM and toll-like receptor ligands with agonistic anti-CD40 was associated with increased mice survival. Subsequent tumor re-challenge also supported adaptive immunity activation, reflected primarily by long-term tumor-specific memory. These results were further verified in metastatic PHEO, where the intratumoral injections of mannan-BAM, toll-like receptor ligands, and anti-CD40 into subcutaneous tumors resulted in significantly less intense bioluminescence signals of liver metastatic lesions induced by tail vein injection compared to the PBS-treated group. Subsequent experiments focusing on the depletion of T cell subpopulations confirmed the crucial role of CD8+ T cells in inhibition of bioluminescence signal intensity of liver metastatic lesions. These data call for a new therapeutic approach in patients with metastatic PHEO/PGL using immunotherapy that initially activates innate immunity followed by an adaptive immune response.

Hypoxia potentiates the cytotoxic effect of piperlongumine in pheochromocytoma models.

Hypoxia is a common feature of solid tumors that activates a plethora of pathways, resulting in proliferation and resistance of cancer cells to radio- and chemotherapy. Pheochromocytomas/paragangliomas (PHEOs/PGLs) with mutations in the gene coding for the subunit B of succinate dehydrogenase (SDHB) are the most aggressive forms of the disease, which is partially due to their pseudohypoxic character, metabolic abnormalities, and elevated reactive oxygen species (ROS) levels. We investigated the effect of piperlongumine (PL), a natural product with cytotoxic properties restricted to cancer cells by significantly increasing intracellular ROS levels, on PHEO cells. Here we report for the first time that PL mediates PHEO cell death by activating both apoptosis and necroptosis in vitro and in vivo. This effect is magnified in hypoxic conditions, making PL a promising potential candidate for use as a therapeutic option for patients with PHEO/PGL, including those with SDHB mutations.