Primary tumors of the paratesticular region are rare, with paratesticular sarcomas constituting a major proportion of these tumors, particularly in the elderly. The paratesticular region consists of mesothelial, various epithelial and mesenchymal cells and may therefore give rise to a number of tumors with various behaviors. Defining the association between the paratesticular mass and the testicle, and differentiation between benign and malignant masses using radiology is challenging, therefore the mass is usually considered to be malignant and radical orchiectomy with high ligation is performed. The present study reports the cases of seven patients with tumors of the paratesticular region and presents the clinical and significant histological features of the tumors. In total, two patients suffered from dedifferentiated liposarcoma (DDLS), two exhibited leiomyosarcoma, two exhibited low‑grade fibromyxoid sarcoma and one case of undifferentiated pleomorphic sarcoma was identified. Radical orchiectomy with high ligation was performed in five cases; simple orchiectomy was performed in one case and excisional biopsy was performed in the remaining case. A leiomyosarcomatous and epithelial membrane antigen (EMA) positive whorl pattern was observed during microscopy in the two DDLS cases. Additionally, one of the low‑grade fibromyxoid sarcoma patients exhibited pleomorphism and mitosis in focal areas. To the best of our knowledge, the present study is the second time low‑grade fibromyxoid sarcoma cases with paratesticular localization have been reported in the literature. Of the seven cases, four patients succumbed to the disease, one patient is living with the disorder and the two cases of DDLS are living without the disease. Paratesticular sarcomas are often aggressive and a multidisciplinary approach is required for the diagnosis and treatment of these tumors.

Osteoclast is a specialized cell that originates from monocytic lineage, communicates closely with osteoblasts under physiological conditions, participates in bone modeling and re-modeling, contributes to calcium homeostasis and osteoimmunity. In pathological conditions, it is involved in many tumors such as giant cell bone tumor (osteoclastoma), aneurysmal bone cyst, osteosarcoma, and metastatic cancers, and it usually causes local spread and progression of the tumor, working against the host. Since osteoclasts play an active role in primary bone tumors and bone metastases, the use of anti-osteoclastic agents significantly reduces the mortality and morbidity rates of patients by preventing the progression and local spread of tumors. Osteoclasts also accompany undifferentiated carcinomas of many organs, especially pancreas, thyroid, bladder and ovary. Undifferentiated carcinomas rich in osteoclasts have osteoclastoma-like histology. In these organs, osteoclastoma-like histology may accompany epithelial carcinomas, and de novo, benign and borderline tumors. Mature and immature myeloid cells, including osteoclasts, play an active role in the tumor progression in primary and metastatic tumor microenvironment, in epithelial-mesenchymal transition (EMT), mesenchymal-epithelial-transition (MET), and cancer stem cell formation. Additionally, they are the most suitable candidates for cancer cells in cell fusion due to their evolutionary fusion capabilities. Myeloid features and markers (CD163, CD33, CD68 etc.) can be seen in metastatic cancer cells. Consequently, they provide metastatic cancer cells with motility, margination, transmigration, chemotaxis, phagocytosis, angiogenesis, matrix degradation, and resistance to chemotherapy. For these reasons, we think that the concept of Epithelial-Mesencyhmal-Myeloid-Transition (EMMT) will be more accurate than EMT for cancer cells with myeloid properties.

CD10 antigen is a 100-kDa-cell surface zinc metalloendopeptidase and it is expressed in a variety of normal and neoplastic lymphoid and nonlymphoid tissues. The aim of this study was to evaluate CD10 expression in urothelial carcinoma of the urinary bladder and to determine the correlation between immunohistochemical (IHC) CD10 expression and histopathologic parameters including grade and stage.