Aside from the scarcity of its location, selecting the appropriate surgical treatment for giant cell tumor of the proximal femur is still debatable [1-5]. Non-surgical management for consideration may include treatment with radiation therapy, embolization, and intralesional injections (steroid, interferon, calcitonin, and denosumab). Early history regarding the use of radiation for GCTb control was unsatisfactory, with local recurrence at 50-70% and the risk of radiation-induced malignant transformation was 7-25% . Recent technological advances have improved outcomes, with reported oncologic control of 85-90% and risk of malignant transformation decreased to 0-8% [6-8]. Pre-operative trans-arterial embolization have been used in difficult to resect GCTB lesions of the spine and pelvis, where extensive blood loss would have been expected . A handful of case reports in maxillofacial surgery have described the use of intralesional injections with either steroid , interferon , calcitonin , bisphosphonates , or denosumab  for GCTb eradication. However, the results are inconclusive and there is no evidence to support its use for a proximal femur lesion.
Joint salvaging surgery is primarily contemplated especially if the patient is relatively young, and the lesion is small and well contained [15-17]. This classically involves extended curettage, +/- adjuvant, and packing the defect either with bone graft or bone cement. Local recurrence rate after extended curettage however varies in literature, as it is 4.5-78% without cementing and 0-29% after cementing [18-20]. En-bloc resection of the lesion will certainly decrease, if not, eliminate the risk of tumor recurrence . Additionally, it is presumed that there is no role for joint salvaging measures if the patient has a displaced pathologic fracture, or if the tumor is uncontained. In the contrary, Sim and Lang (1997) published a case report about a proximal femur GCTb with a transcervical fracture treated with internal fixation using a dynamic hip screw combined with valgus osteotomy, curettage, and bone grafting . The latest follow-up was at 35 months, and the patient did not show any evidence of metastasis nor implant failure. However, at the latest follow-up there was a noted deformation of the femoral head that was absent prior to surgery. Furthermore, pre-operatively their patient did not have an extensive cortical break or soft-tissue extension unlike in our case. For our case, we opted for tumor resection and reconstruction due to the patient’s pathologic fracture, cortical break, soft-tissue extension, better tumor control and the lesser incidence of recurrence. The options for hip reconstruction after resection, includes excisional arthroplasty, hemi-arthroplasty or total hip replacement.
Hip joint reconstruction following excision is valuable for maintaining the stability and normalization of gait. However, there is always the risk of sacrificing vital tendinous insertions of hip abductors, adductors, flexors, and external rotators if the excision involves removing either the greater or the lesser trochanter. Furthermore, there is also the risk of taking out the dense vertically oriented calcar femorale at the posteromedial portion of the proximal femur, which support majority of the hip axial load. As with our patient, we expected to resect distal to the base of the lesser trochanter so we opted for a calcar-replacing long femoral stem. The aim is to have proximal portion of the femoral implant sitting on top of the femoral cortex, while the long stem provides stability and diaphyseal fixation. There are also designed holes on the proximal part of the femoral implant for re-attachment of the hip abductors and the iliopsoas (Figure 4B). Another option for hip reconstruction after excision of the proximal femur, would be an Allograft-prosthesis Composite (APC). Malhotra et al., reported a case series of 18 patients diagnosed with GCTb of the proximal femur treated with excision of the proximal femur, and APC using irradiated fresh-frozen allograft. With a mean follow-up of 54 months, all patients had complete graft union and excellent Harris hip scores in 13 patients . We did consider using a proximal femoral allograft composite prior to the operation, however there was none available at our institution at that time. We also decided to do a cemented femoral fixation not only for stability, but also since the use PMMA bone cement seems to reduce tumor recurrence rate.
A review of literature investigating the treatment of proximal femur GCTb with excision and joint replacement was done (Table 1). The objectives of the literature search included analysis of the clinical outcomes, check for any tumor recurrence, and to determine any complications. The articles mostly were case report or case series, and there was heterogeneity with the type of implants used amongst the studies. All but one study stated no tumor recurrence on the latest follow-up. Out of the 51 patients with proximal femur GCTb treated with joint replacement in literature, there were only two patients who have had tumor recurrence. All studies reported improvement of latest functional outcome scores (Harris hip or MSTS score).
||No. of patients
||Type of resection
||Mean follow-up (months)
|Kulkarni SS et al., 
||Charnley type low-friction THA
||No tumor recurrence; Patient pain-free, full-weight bearing, but with mild Trendelenburg lurch
|Sakayama K et al., 
||Two THA (Implant not specified) and two bipolar hemi-arthroplasty
||No tumor recurrence. The mean MSTS functional score was 93%.
|Khan SA et al.,
||Customized, bipolar, cemented proximal femoral megaprosthesis
||No tumor recurrence; No incidence of aseptic loosening or dislocation. The mean MSTS score is 28.3.
|Nakano S et al., 
||Cemented custom-made prosthesis
||384 (32 years)
||No tumor recurrence, and with signs of bone formation at muscle re-attachment sites to the prosthesis. Mean Harris hip score of 100.
|Dhatt S et al., 
||Custom made megaprosthesis
||No tumor recurrence nor any metastasis; no implant loosening. The MSTS score is 26.7.
|Malhotra R et al., 
||Uncemented Acetabular cup; ceramic-on-ceramic bearings; proximal femoral allograft-prosthesis composite
||No tumor recurrence; Harris hip scores: 13 excellent and 5 good outcomes. All allografts united.
|Wisbek AE et al., 
||Total hip replacement (8 pxs), hemi-arthroplasty (1 px), endoprosthetic joint replacement (5 pxs)
Mean MSTS scores for THR was 25.7 and endoprosthesis was 24.7.
Complications: Two patients treated with THR had tumor recurrence; 1 THR and 1 endoprosthesis had dislocation; 1 hemi-arthroplasty was revised to a THR and 1 THR had an acetabular cup revision.
A review of literature investigating the treatment of proximal femur GCT with excision and hip joint replacement.
Comparable to data reported on literature, our patient had significant improvement in his MSTS score. Albeit the short term follow-up, it is important to note that the patient did not have any tumor recurrence or any mechanical signs of implant failure. It would be interesting to note the long term survivorship of this implant and follow-up the functional outcome of the patient in the future.