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Titanium (Ti) has been used in metallic implants since the 1950s due to various biocompatible and mechanical properties. However, due to its high Young’s modulus, it has been modified over the years in order to produce a better biomaterial. Tantalum (Ta) has recently emerged as a new potential biomaterial for bone and dental implants. It has been reported to have better corrosion resistance and osteo-regenerative properties as compared to Ti alloys which are most widely used in the bone-implant industry. Currently, Tantalum cannot be widely used yet due to its limited availability, high melting point, and high-cost production. This review paper discusses various manufacturing methods of Tantalum alloys, including conventional and additive manufacturing and also discusses their drawbacks and shortcomings. Recent research includes surface modification of various metals using Tantalum coatings in order to combine bulk material properties of different materials and the porous surface properties of Tantalum. Design modification also plays a crucial role in controlling bulk properties. The porous design does provide a lower density, wider surface area, and more immense specific strength. In addition to improved mechanical properties, a porous design could also escalate the material's biological and permeability properties. With current advancement in additive manufacturing technology, difficulties in processing Tantalum could be resolved. Therefore, Tantalum should be considered as a serious candidate material for future bone and dental implants.

Background: Despite recent promising findings from immunotherapy and other targeted medicines, individuals with metastatic Clear Cell Renal Cell Carcinoma (mCCRCC) still have a poor prognosis. Biomarkers associated with metastatic status in CCRCC are important for early detection and for the identification of new therapeutic targets. Fibroblast activation protein (FAP) expression is associated with development of early metastases and worse cancer-specific survival. Tumor-associated collagen signature (TACS) is type of collagen that develop during tumor growth and associated with tumor invasion.Methods: 26 metastatic clear cell renal cell carcinoma patients that underwent nephrectomy were admitted to this study. Data regarding age, sex, Fuhrman’s grade, tumor diameter, staging, FAP expression, and TACS grading were collected. Spearman rho test was used to correlate FAP expression and TACS grading in both primary tumors and metastases, and with patients age and sex.Results: FAP expression correlated positively with TACS degree (Spearman rho test r = 0.51; p = 0.0001). FAP was positive in 25 (96%) of all intratumor samples and positive in 22(84%) of all stromal sample.Conclusion: FAP can be used as prognostic factor in metastatic CCRCC, its presence can predict aggressiveness of mCRCC and poorer outcome in patient. Furthermore TACS can be also used for prediction of aggressiveness and metastasis due to the changes are necessary for tumor to invade other organs.

Background: Adrenal masses are common incidental findings, most of which are benign and non-functional. Malignant adrenal tumors, however, differ from their benign counterpart and confer poor prognosis. In addition, the oncocytic variants of these tumors present challenges to clinicians owing to their unique biologic behavior and rarity. Case presentation: We present a case report of a 61-year-old male with a T2N0M0 adrenocortical oncocytic neoplasm of the right adrenal gland. The patient complained of worsening right upper quadrant abdominal pain and was diagnosed with a right adrenal mass after an abdominal CT-scan examination two weeks before. Subsequently, the patient underwent open adrenalectomy due to a history of abdominal surgery. Due to unique oncocytic biologic behavior, we used the Lin–Weiss–Bisceglia criteria to predict a malignancy instead of the Weiss system. We only found one malignant criterion, which showed a small tumor invasion on the vascular bed on one histopathological section. Thus, we diagnosed it as malignant adrenocortical oncocytic neoplasm. Furthermore, the PET Scan showed no residual mass or pathological metabolic activity on the tumor bed and metastatic sign. Conclusions: The diagnosis of the malignant oncocytic adrenal case is based on the histopathological criteria. Based on this case, we suggest a thorough histopathological examination to determine malignant criteria in adrenal neoplasm cases.