Decade Later Presentation of an Intraosseous Metallic Foreign Body in the Pelvis: A Case Report and Literature Review.

Introduction: Metallic foreign body reactions are observed many times, usually in the early periods. However, late presentations are often uncommon. Management of these foreign bodies varies from a military setting to a civilian setting where saving a patient's life is the priority. Case Report: In this case report, we present a 49-year-old soldier with recent onset swelling in the right gluteal region with elevated local temperature and minimal tenderness. The patient suffered a land mine blast injury 10 years ago with multiple injuries to the chest, abdomen, and lower limb. According to military protocols, he was initially managed for life-threatening chest and open abdominal injuries. The right lower limb was non-salvageable and underwent above-knee amputation. A dormant metallic foreign body, which was retained inside the right iliac bone, presented a decade later with a subacute non-pyogenic abscess. Conclusion: The primary goal in military injuries is always to save a patient's life. While acute management remains the same for both military and civilian injuries. In military injuries, deep-seated, inactive foreign bodies are often left behind in order to avoid fresh plane dissection, and to minimize blood loss for early stabilization and save patient lives. Late-onset inflammatory responses are the cause of the delayed presentation of retained foreign bodies.

Comparison of Denosumab and Zoledronic acid as neoadjuvant therapy in patients with giant cell tumor of bone.

OBJECTIVES: Both Zoledronic acid and denosumab have been utilized in neo-adjuvant setting for facilitating surgery and downsizing the lesion in Giant cell tumor (GCT). This study is aimed at comparing Zoledronic acid and Denosumab, when used in neo-adjuvant setting, in terms of radiological and clinical outcomes in GCT undergoing surgical intervention. PATIENTS AND METHODS: Patients undergoing surgical intervention for GCT who received either denosumab or Zoledronic acid as neoadjuvant agents were retrospectively analyzed for reduction in tumor load radiologically, change in surgical plan after therapy, facilitation of surgery, therapy related complications, cost of treatment, rate of local recurrence and clinical outcomes. RESULTS: Twenty patients received denosumab and 19 patients received Zoledronic acid as neoadjuvant agent. There was no significant difference in radiological outcomes, facilitation of surgery and clinical outcomes at end of follow-up. Zoledronic acid group had lower number of recurrences, however, not statistically significant. Therapy with Zoledronic acid was significantly cheaper (p = 0.001). CONCLUSION: Zoledronic acid is a cheaper alternative to denosumab in terms of solidification of lesion, reducing recurrence rates and improving clinical outcomes. Larger prospective studies required to further delineate this outcome with Zoledronic acid.

Prediction of chemotherapy response by PET-CT in osteosarcoma: correlation with histologic necrosis.

BACKGROUND: The current standard for neoadjuvant chemotherapy (NACT) response evaluation in osteosarcoma is histopathologic necrosis (HN). However, it is accessible only after NACT completion and may get affected by confounding factors. Thus, noninvasive surrogate such as (18)Fluorine-Fluorodeoxyglucose-positron emission tomography-computerized tomography (PET-CT) scan would be useful to individualize therapy. METHODS: Thirty-one treatment naive osteosarcoma patients evaluated prospectively by PET-CT scan preceding and after 3 cycles of NACT and surgery during 2006 to 2008. Various anatomic and metabolic parameters of PET-CT scan were compared with HN (good response ≥90% HN) as reference standard. Receiver operating characteristic curves were generated to assess the best threshold and predictability. RESULTS: Median age was 17 years; 25 were male patients and 23 were nonmetastatic. Ten cases were good, whereas 21 cases were poor histologic responders. PET-CT parameters including post-NACT (2) and pre-NACT (1) standard uptake value (SUV)max ratio (SUV2:SUV1), SUV2, pre-NACT and post-NACT volumes (V1and V2), change in V after NACT, pre-NACT and post-NACT metabolic burden (MB) and change in MB after NACT correlated with HN. Two independent predictors were identified in stepwise multivariable analysis; if V1 ≤300 mL and SUV2:SUV1 ≤0.48, observed good histologic response proportions was 83%, whereas if V1 >300 mL and SUV2:SUV1 >0.48, it was 0%. CONCLUSIONS: NACT response can be predicted reliably by PET-CT scan early in disease course (even at baseline) and PET-CT parameters correlate well with HN. MB seems to be sensitive substitute for response evaluation. Independent predictors may have wider clinical applications if further validation can be done.

Role of MRI in osteosarcoma for evaluation and prediction of chemotherapy response: correlation with histological necrosis.

BACKGROUND: Histological necrosis, the current standard for response evaluation in osteosarcoma, is attainable after neoadjuvant chemotherapy. OBJECTIVE: To establish the role of surrogate markers of response prediction and evaluation using MRI in the early phases of the disease. MATERIALS AND METHODS: Thirty-one treatment-naïve osteosarcoma patients received three cycles of neoadjuvant chemotherapy followed by surgery during 2006-2008. All patients underwent baseline and post-chemotherapy conventional, diffusion-weighted and dynamic contrast-enhanced MRI. Taking histological response (good response ≥90% necrosis) as the reference standard, various parameters of MRI were compared to it. A tumor was considered ellipsoidal; volume, average tumor plane and its relative value (average tumor plane relative/body surface area) was calculated using the standard formula for ellipse. Receiver operating characteristic curves were generated to assess best threshold and predictability. After deriving thresholds for each parameter in univariable analysis, multivariable analysis was carried out. RESULTS: Both pre-and post-chemotherapy absolute and relative-size parameters correlated well with necrosis. Apparent diffusion coefficient did not correlate with necrosis; however, on adjusting for volume, significant correlation was found. Thus, we could derive a new parameter: diffusion per unit volume. CONCLUSION: In osteosarcoma, chemotherapy response can be predicted and evaluated by conventional and diffusion-weighted MRI early in the disease course and it correlates well with necrosis. Further, newly derived parameter diffusion per unit volume appears to be a sensitive substitute for response evaluation in osteosarcoma.

VEGF expression as a prognostic marker in osteosarcoma.

BACKGROUND: The vascular endothelial growth factor (VEGF) pathway is the key regulator of angiogenesis. In osteosarcoma baseline VEGF is of proven prognostic value but prognostic potential of post-NACT VEGF expression is largely unexplored. PROCEDURE: Treatment naive patients with osteosarcoma were subjected to initial staging workup followed by three cycles of neoadjuvant chemotherapy (NACT) and surgery; resected tumors were assessed for histological necrosis by Huvos grading. Initial biopsy and resected tumor specimens post-NACT were examined for VEGF expression by immunohistochemistry. Positive VEGF expression was considered when intensive positive staining was observed in >10% of the tumor cells. VEGF expression at baseline was compared with grade of tumor; pre-NACT and post-NACT VEGF expression were compared with histological necrosis. Receiver operating characteristic curves were generated to assess best threshold and predictability. RESULTS: A total of 31 patients were recruited with median age of 17 years (range 5-66 years); male/female ratio was 25:6; 23 patients (74%) were non-metastatic. At baseline, there was 90% concordance between positive VEGF expression and higher histological grade (28/31); baseline VEGF expression did not correlate well with stage and histological necrosis. Twenty-one (67%) were poor and 10 (33%) were good histologic responders; post-NACT VEGF expression as well as VEGF change following NACT significantly correlated with histological necrosis. CONCLUSION: Positive VEGF expression in surviving tumor cells post-NACT in resected tumors appears to be an important negative prognostic factor in osteosarcoma which may help future therapies to be identified according to the angiogenic potential of the disease.