Malignant peripheral nerve sheath tumors (MPNSTs) are a complex group of malignant tumors originating from nerve cells or benign peripheral nerve sheath tumors and are commonly found in major plexus/nerve root sites such as the limbs, head, and neck. Malignant peripheral nerve sheath tumors originating in the ureter are extremely rare. Herein, we report the case of a 63-year-old patient with a malignant peripheral nerve sheath tumor of the right ureter who underwent laparoscopic radical resection of the right kidney and ureter. The patient also had stage 5 chronic kidney disease (CKD). Therefore, chemotherapy and radiotherapy were not considered. No tumor recurrence was observed during the follow-up period.

Trousseau syndrome (TS) is a malignant tumor-mediated complication of the hypercoagulable state with an unknown etiology. Laboratory testing results in patients with TS have indicated elevated D-dimer levels. The imaging analysis in patients who had undergone stroke has shown the presence of several cerebral infarction lesions in multiple regions. Since patients have had malignant tumors for a long time when they suffer from a secondary stroke, the optimum time for radical tumor treatment is usually missed. This study reports a case to improve the early screening and detection of TS and reduce the risk of recurrence of cerebral infarction.

BACKGROUND: Primary malignant cardiac mesenchymoma tumors are rarely described in the medical literature, with only a few published cases.
METHODS: We present a case of a primary malignant mesenchymoma in the left atrium extending to the left and right inferior pulmonary vein orifices, accompanied by mechanical obstruction of the mitral valve. The patient underwent surgical removal and radiotherapy.
CONCLUSIONS: Cardiac tumors are categorized as primary and secondary tumors. Primary cardiac tumors are extremely rare, with a low incidence rate of 0.001-0.28 %. Primary malignant tumors constitute less than 25 % of them. Malignant mesenchymoma is considered the rarest of them. These tumors proliferate and may cause metastases, making them highly malignant with a poor prognosis, especially if accompanied by metastases or invasion of nearby tissues.
CONCLUSIONS: The poor prognosis of cardiac mesenchymoma comes from the fact that it is aggressive and rapidly growing, which causes a rapid progression of mechanical symptoms and metastasis to nearby tissues, which makes it classified as a highly malignant tumor with a low survival rate. Surgical resection remains the mainstay of treatment, in addition to follow-up with chemotherapy or radiotherapy according to the grade of the disease, which was the case with our patient and the same as reported in previous literature. However, further research and case reports are needed better to understand the optimal management of this aggressive tumor.

Development of a myxofibrosarcoma in the breast tissue is extremely rare. Reported here is a case of myxofibrosarcoma found in the left breast tissue of a male in his late fifties. The patient first underwent tumor resection, followed by a left mastectomy with the reconstruction of the vastus lateralis valve. The tumor comprised atypical spindle-shaped cells in a myxoid matrix with elongated blood vessels. Myxofibrosarcoma was diagnosed based on histology and immunohistochemical examination results performed for differential diagnosis. At two years and two months after the mastectomy, no local occurrence or metastasis had occurred.

Retroperitoneal fibrosis (RF) is a rare disease, which can be primary (idiopathic) or secondary. We present the case of a 56-year-old patient with symptomatic RF, in whom, after ineffective treatment with glucocorticoids, immunosuppressants, and non-steroidal anti-inflammatory drugs for one year and a progressive clinical course, a follicular lymphoma in the retroperitoneal space and several lymphoma nodes was identified. We also include a literature review on differential diagnosis through image inspection and case reports of lymphoma mimicking RF.

(1) Background: accelerator-based neutron sources are a new frontier for BNCT but many technical issues remain. We aimed to study such issues and results in larger-animal BNCT (cats and dogs) with naturally occurring, malignant tumors in different locations as an intermediate step in translating current research into clinical practice. (2) Methods: 10 pet cats and dogs with incurable, malignant tumors that had no treatment alternatives were included in this study. A tandem accelerator with vacuum insulation was used as a neutron source. As a boron-containing agent, 10B-enriched sodium borocaptate (BSH) was used at a dose of 100 mg/kg. Animal condition as well as tumor progression/regression were monitored. (3) Results: regression of tumors in response to treatment, improvements in the overall clinical picture, and an increase in the estimated duration and quality of life were observed. Treatment-related toxicity was mild and reversible. (4) Conclusions: our study contributes to preparations for human BNCT clinical trials and suggests utility for veterinary oncology.

BACKGROUND: Neurofibromatosis type 1 (NF-1) predisposes individuals to the development of benign and malignant tumors. The association of NF-1, juvenile xanthogranuloma (JXG), and juvenile myelomonocytic leukemia has been described in the literature. It is unclear whether JXG alone constitute a risk factor for leukemia or other malignancies in children with NF-1.
OBJECTIVE: To determine if there is an association between NF-1, JXG, and malignancy.
METHODS: We conducted a retrospective case-control study comparing children with NF-1 and malignancy (cases) with sex- and age-matched children with NF-1 without malignancy (controls).
RESULTS: We identified 739 patients with NF-1 over a 20-year period, 14 of whom also had a diagnosis of malignancy. These cases include 9 (64%) boys and 5 (36%) girls. JXG were found in 4/14 (28.5%) cases and 6/29 (21%) controls (odds ratio 1.5, 95% confidence interval 0.35-6.6, P = .56).
CONCLUSIONS: Retrospective design, small number of cases, and inconsistent documentation of clinical findings, including age at disappearance of JXG.
CONCLUSIONS: Juvenile xanthogranulomas do not appear to confer an increased risk for malignancy in children with NF-1.

Tumors of the clitoris are very rare. Isolated case reports are available in literature. This case report highlights the importance of this disease, due to its high malignant potential and treatment options. We had come across a rare tumor of the clitoris in a young girl, reported to be malignant extrarenal rhabdoid tumor and patient had a short life span of 6 months.