Case report: An uncommon presentation of extramedullary plasmacytoma without a concurrent diagnosis of multiple myeloma.

Introduction: Extramedullary plasmacytoma (EMP) is an uncommon solitary tumor originating from neoplastic plasma cells located outside the bone marrow. Despite its rarity, the occurrence of EMP without a concurrent diagnosis of multiple myeloma (MM) is considered extremely rare. Approximately 80-90% of EMP cases are found in the head and neck region, with a higher incidence in men aged between 50 and 60 years. The current treatment modalities include radiotherapy (RT) as a first-line approach, with surgery or chemotherapy regarded as other therapeutic options. While RT proves effective in the majority of EMP cases, there are instances where the tumor remains refractory to radiation. In this case report, we present an unusual scenario of EMP resistant to RT without concurrent signs of multiple myeloma which was successfully treated with surgery followed by systemic therapy. Case report: A 72-year-old male was admitted to the Head and Neck Cancer Clinic with a 6-month history of swallowing difficulties. He denied experiencing weight loss or pain on swallowing. Basic laboratory tests yielded results within normal limits, except for beta-2 microglobulin. Physical examination revealed an enlarged submandibular lymph node on the right side. Fiberoptic examination identified a soft tissue polypoid mass within the right piriform fossa, slightly protruding into the vocal slit. A CT scan displayed a well-circumscribed 2 cm polypoid, homogeneously enhancing soft tissue mass adjacent to the posterior surface of the epiglottis and the right side of the tongue base. Bone marrow biopsy revealed no abnormalities, and there were no clinical or laboratory signs of multiple myeloma. Based on the tumor biopsy results and imaging studies, a diagnosis of EMP was made. Due to the lack of response to RT, surgical removal of the tumor was pursued, followed by systemic therapy. Ultimately, the patient achieved full recovery with effective disease control. Conclusion: In conclusion, EMP without concurrent multiple myeloma is an exceedingly rare condition that demands a multidisciplinary approach for both diagnosis and treatment. Moreover, although RT continues to be the primary standard treatment for EMP, in some cases other therapeutic regimens prove to be successful.

Two sisters diagnosed with familial paraganglioma syndrome type 1 (FPGL1) and multiple endocrine neoplasia type 2A (MEN2A).

BACKGROUND: In clinical practice, genetic testing has become standard for many cancerous diseases. While a diagnosis of a single hereditary syndrome is not uncommon, the coexistence of two genetic diseases, even with partially common symptoms, remains unusual. Therefore, targeted next-generation sequencing (NGS), along with genetic consultation and imaging studies, is essential for every patient with confirmed paraganglioma. In this report, we present two sisters diagnosed with multiple endocrine neoplasia type 2 (MEN2A) and familial paraganglioma syndrome type 1 (FPGL1). CASE PRESENTATION: After presenting to the clinic with neck tumors persisting for several months, both patients underwent tumor removal procedures following imaging and laboratory studies. Pathological reports confirmed the diagnosis of paragangliomas. Subsequently, genetic testing, including NGS, revealed a mutation in the rearranged during transfection (RET) gene: the heterozygous change (c.2410G > A), (p.Val804Met), and a variant of the succinate dehydrogenase complex subunit D (SDHD) gene: (c.64 C > T), (p.Arg22Ter). Subsequently, thyroidectomy procedures were scheduled in both cases. CONCLUSION: To the best of our knowledge, this is the first report presenting these two mutations in two related patients, resulting in distinctive genetic syndromes with similar manifestations. This underscores that although infrequent, multiple hereditary disorders may co-occur in the same individual.

Assessment of Hematopoietic Response to Total Body Irradiation in a Rat Experimental Model.

BACKGROUND: Exposure to high doses of total body irradiation (TBI) may lead to the development of acute radiation syndrome (ARS). This study was conducted to establish an experimental rat model of TBI to assess the impact of different doses of TBI on survival and the kinetics of changes within the hematopoietic system in ARS. MATERIALS AND METHODS: In this study, 132 Lewis rats irradiated with a 5Gy or 7Gy dose served as experimental models to induce ARS and to evaluate the hematopoietic response of the bone marrow (BM) compartment. Animals were divided into 22 experimental groups (n = 6/group): groups 1-11 irradiated with 5Gy dose and groups 12-22 irradiated with 7Gy dose. The effects of TBI on the hematopoietic response were assessed at 2, 4, 6, 8 hours and 5, 10, 20, 30, 40, 60 and 90 days following TBI. Signs of ARS were evaluated by analyzing blood samples through complete blood count in addition to the clinical assessment. RESULTS: Groups irradiated with 5Gy TBI showed 100% survival, whereas after 7Gy dose, 1.6% mortality rate was observed. Assessment of the complete blood count revealed that lymphocytes were the first to be affected, regardless of the dose used, whereas an "abortive rise" of granulocytes was noted for both TBI doses. None of the animals exhibited signs of severe anemia or thrombocytopenia. All animals irradiated with 5Gy dose regained initial values for all blood cell subpopulations by the end of observation period. Body weight loss was reported to be dose-dependent and was more pronounced in the 7Gy groups. However, at the study end point at 90 days, all animals regained or exceeded the initial weight values. CONCLUSIONS: We have successfully established a rat experimental model of TBI. This study revealed a comparable hematopoietic response to the sublethal or potentially lethal doses of ionizing radiation. The experimental rat model of TBI may be used to assess different therapeutic approaches including BM-based cell therapies for long-term reconstitution of the hematopoietic and BM compartments allowing for comprehensive analysis of both the hematological and clinical symptoms associated with ARS.

Chimeric Cell Therapies as a Novel Approach for Duchenne Muscular Dystrophy (DMD) and Muscle Regeneration.

Chimerism-based strategies represent a pioneering concept which has led to groundbreaking advancements in regenerative medicine and transplantation. This new approach offers therapeutic potential for the treatment of various diseases, including inherited disorders. The ongoing studies on chimeric cells prompted the development of Dystrophin-Expressing Chimeric (DEC) cells which were introduced as a potential therapy for Duchenne Muscular Dystrophy (DMD). DMD is a genetic condition that leads to premature death in adolescent boys and remains incurable with current methods. DEC therapy, created via the fusion of human myoblasts derived from normal and DMD-affected donors, has proven to be safe and efficacious when tested in experimental models of DMD after systemic-intraosseous administration. These studies confirmed increased dystrophin expression, which correlated with functional and morphological improvements in DMD-affected muscles, including cardiac, respiratory, and skeletal muscles. Furthermore, the application of DEC therapy in a clinical study confirmed its long-term safety and efficacy in DMD patients. This review summarizes the development of chimeric cell technology tested in preclinical models and clinical studies, highlighting the potential of DEC therapy in muscle regeneration and repair, and introduces chimeric cell-based therapies as a promising, novel approach for muscle regeneration and the treatment of DMD and other neuromuscular disorders.

Transplantation of Donor-Recipient Chimeric Cells Restores Peripheral Blood Cell Populations and Increases Survival after Total Body Irradiation-Induced Injury in a Rat Experimental Model.

Current therapies for acute radiation syndrome (ARS) involve bone marrow transplantation (BMT), leading to graft-versus-host disease (GvHD). To address this challenge, we have developed a novel donor-recipient chimeric cell (DRCC) therapy to increase survival and prevent GvHD following total body irradiation (TBI)-induced hematopoietic injury without the need for immunosuppression. In this study, 20 Lewis rats were exposed to 7 Gy TBI to induce ARS, and we assessed the efficacy of various cellular therapies following systemic intraosseous administration. Twenty Lewis rats were randomly divided into four experimental groups (n = 5/group): saline control, allogeneic bone marrow transplantation (alloBMT), DRCC, and alloBMT + DRCC. DRCC were created by polyethylene glycol-mediated fusion of bone marrow cells from 24 ACI (RT1a) and 24 Lewis (RT11) rat donors. Fusion feasibility was confirmed by flow cytometry and confocal microscopy. The impact of different therapies on post-irradiation peripheral blood cell recovery was evaluated through complete blood count, while GvHD signs were monitored clinically and histopathologically. The chimeric state of DRCC was confirmed. Post-alloBMT mortality was 60%, whereas DRCC and alloBMT + DRCC therapies achieved 100% survival. DRCC therapy also led to the highest white blood cell counts and minimal GvHD changes in kidney and skin samples, in contrast to alloBMT treatment. In this study, transplantation of DRCC promoted the recovery of peripheral blood cell populations after TBI without the development of GVHD. This study introduces a novel and promising DRCC-based bridging therapy for treating ARS and extending survival without GvHD.

Donor-Recipient Chimeric Cell Transplantation as the Bridging Therapy for Mitigating Total Body Irradiation-Induced Injury.

In recent years, cell-based therapies have emerged as a promising approach for mitigating radiation-induced injury. Acute radiation syndrome (ARS) results from exposure to high doses of radiation over a short time period. This study aimed to compare the efficacy of donor-recipient chimeric cell (DRCC) therapy in mitigating ARS induced by a total body irradiation (TBI) dose of 10 gray (Gy). Thirty irradiated Lewis rats were employed as ARS models to assess the efficacy of systemic-intraosseous transplantation of different cellular therapies in five experimental groups (n = 6/group): saline control, isogenic bone marrow transplantation (isoBMT), allogeneic BMT (alloBMT), DRCC, and alloBMT+DRCC. DRCC were created by polyethylene glycol-mediated fusion of bone marrow cells from 24 ACI (RT1a) and 24 Lewis (RT11) rat donors. The creation of DRCC and chimeric state was confirmed by flow cytometry (FC) and confocal microscopy (CM). Recovery of blood parameters was evaluated through complete blood count analysis. Graft-versus-host disease (GvHD) signs were assessed clinically and histopathologically using kidney, skin, and small intestine biopsies. FC and CM confirmed the fusion feasibility and the chimeric state of DRCC. A 100% mortality rate was observed in the saline control group, whereas a 100% survival was recorded following DRCC transplantation, correlating with significant recovery of peripheral blood parameters. In addition, no clinical or histopathological signs of GvHD were observed after DRCC and alloBMT+DRCC transplantation. These findings confirm efficacy of DRCC in mitigating GvHD, promoting hematopoietic recovery, and increasing animal survival following TBI-induced ARS. Moreover, tolerogenic and immunomodulatory properties of DRCC therapy support its feasibility for clinical applications. Therefore, this study introduces DRCC as an innovative bridging therapy for alleviating the acute effects of TBI, with broad implications for stem cell research and regenerative medicine.

A new therapeutic approach in Gorham-Stout disease: a case report.

Background: Gorham-Stout disease is a rare condition of unknown prevalence and unknown exact cause. Its pathogenesis is based on enhanced osteoclastic activity leading to bone resorption and bone replacement by distended lymphatic vessels. Because of its rarity and a various range of symptoms the disease may give, diagnosis is challenging and a strong index of suspicion is required. Although it is a benign condition, the prognosis may be unpredictable. The treatment options suggested so far are limited, and every case should be provided with the best individual approach. Herein, we present a case report of Gorham-Stout disease managed with a regular lump drainage with a good response and control of the patient symptoms over a period of 20 years. Case report: A 23-year-old male was admitted to the Head and Neck Cancer Clinic with a 6-month history of a left-sided neck lump. Other symptoms reported were neck pain and general weakness. The basic laboratory tests were within normal limits. On physical examination, a large round lump on the left side of a patient's neck and left armpit were noticed. They were about several centimeters in diameter, soft on palpation, but firmly attached to the underlying tissue. CT scan revealed large lymphatic left-sided masses of the neck and axillary fossa and multiple osteolytic lesions in the patient's vertebrae. Together with the biopsy findings and imaging studies, a diagnosis of Gorham-Stout Syndrome was made. The patient was then scheduled for a regular cystic drainage with good control of a disease for over a period of 20 years. Conclusion: Gorham-Stout disease is a rare challenging condition, and the available treatment options remain sparse. Although surgical approach is effective, it is not always possible. In addition, the risk of radiotherapy-induced malignancy shows that this therapy may eventually result in unfavorable response. Depending on symptoms and the disease location, this condition requires an individual treatment plan. The presented case illustrates that a minimally invasive approach may result in a good control of the Gorham-Stout syndrome and may stand as an alternative treatment option for some patients with this condition.