Introduction: The periacetabular region is a common location for nonprimary neoplastic tumors. Although these tumors were historically treated with a cemented acetabular implant, we previously reported on the short-term follow-up on the use of a tantalum acetabular shell to reconstruct these defects. This study expands our previous report on longer follow-up, with specific emphasis on patient and implant survivorship, radiographic results, and clinical outcomes. Methods: Fifty-eight patients (32 women and 26 men) were treated using a tantalum acetabular implant and total hip arthroplasty to reconstruct a nonprimary neoplastic process between 2001 and 2014. The mean age and body mass index were 62 years and 28 kg/m(2), respectively. The most common diagnosis was metastatic disease (n = 29). The patients' medical records and radiographs were reviewed to assess Harris hip scores and radiographic fixation. The mean follow-up for surviving patients was 8 years. Results: At the most recent follow-up, 41 patients were dead of the disease and 17 were alive with the disease and no cases of acetabular implant revision were reported. Two patients had a progressive radiolucent line; however, they also had radiographic evidence of local disease progression. After reconstruction, patients had a significant (P = 0.0001) increase in their Harris hip score (37 vs. 72). Discussion: In patients with periacetabular metastatic diseases and hematologic malignancies treated with total hip arthroplasty, a highly porous tantalum revision-type shell fixed with multiple screws, and supplemental support with acetabular augments or cup-cage reinforcement, can successfully provide patients with a stable, well-fixed, and durable construct, with no cases of mechanical failure at mid-term follow-up.