Sherman, Courtney E.

Abstract Extra-axial chordoma (EAC) is a very rare, malignant tumor with metastatic potential that arises in the extra-axial skeleton and soft tissues. We report the case of a 51-year-old right-handed male with EAC of the left capitate. He underwent capitate resection and wrist arthrodesis utilizing scaphoid autograft with the treatment goal of minimizing risk of tumor recurrence and metastasis while maximizing hand and wrist function. His radiographic outcome demonstrated union of his arthrodesis site. However, 7 months postoperatively, he started experiencing increased hand and wrist pain and was found to have early tumor reoccurrence. Few cases of EAC have been reported in the literature. EAC is typically treated with resection alone, although there is a limited role for chemotherapy and radiation in the setting of locally reoccurring or metastatic disease. Functional outcomes of the affected extremity and survival outcomes vary widely. This is the first report in the literature of EAC of a single carpal bone and describes an innovative technique for definitive surgical treatment of this rare tumor. Utilization of scaphoid autograft for wrist arthrodesis in the setting of capitate resection allows the use of autograft in a wrist arthrodesis without the additional morbidity of iliac crest bone grafting. This case also demonstrates the importance of appropriate diagnosis and oncologic technique at the index surgery.

Abstract Background Echinococcus multilocularis is a destructive zoonotic cestode with low human incidence. Hydatid disease classically presents with hepatic or lung involvement with infrequent extrahepatic bone destruction. Diagnosis is challenging due to its latency and mimicry. Fig.1: Case 1 - X-ray imaging of the pelvis shows osseous destruction of the iliac crest secondary to known osteomyelitis status post left ilium debridement. Fig.2: Case 1 - Magnetic resonance imaging demonstrates extensive osteomyelitis throughout left ilium. Stable scattered focal fluid collections seen throughout the left lower quadrant. Methods CASE 1: A 57 year-old Albanian male with diabetes, latent TB, and left iliac lytic lesion presented with 4 weeks of left flank pain and was treated with 6 weeks of IV Ceftriaxone and Flagyl. 2 years later he returned with flank pain and purulent lumbar drainage. Hip x-ray suggested chronic osteomyelitis, with left psoas fluid collections on CT. Bartonella, Q fever, Brucella, HIV, AFB and fungal serologies were negative. Hemipelvis debridement revealed structures concerning for hydatid disease. Echinococcus IgG was equivocal. Histopathology was consistent with Echinococcus multilocularis species, and albendazole was started. On follow-up, he presented with left hip tenderness and toe extensor weakness. Labs showed mild leukocytosis. CT revealed progressive destruction of the left iliac with sacroiliac extension concerning for abscess. CASE 2: A 36 year-old female presented with lung and liver cysts, progressive dyspnea, and non-productive cough. She lived in Africa, Asia, and Europe and consumed local street food and unpasteurized milk. Hobbies included spelunking and swimming in freshwater lakes. She had exposure to stray animals, but denied bites or scratches. Over 4 years dyspnea progressed to orthopnea. MR abdomen revealed a 10x6x12cm liver cyst and chest CT showed 2 fluid-attenuating lesions in the LLL and RLL, measuring 4.9 x 6.0 cm and 6.8 x 4.3 cm respectively. Echinococcus, Bartonella, Q fever, Brucella, HIV, AFB and fungal serologies were negative. Schistosomiasis serology was equivocal. Fig. 3: Case 2 - MRI abdomen demonstrating 10x6x12cm liver cyst Fig. 4: Case 2 - Chest CT showed 2 dominant fluid attenuating lesions within the LLL and RLL. The larger lesion in RLL measures 6.8 x 4.3 cm. The left lower lobe lesion measures 4.9 x 6.0 cm. Results Patient 1 underwent type I hemipelvectomy. Patient 2 underwent pulmonary segmentectomy and liver lobectomy. Both were continued on albendazole. Fig. 5: Case 1 - Photo taken during debridement of left ileac and hip. Note presence of white cysts discovered intraoperatively. Fig. 6: Case 1 - Histopathologic slides (H&E stain) demonstrating hooks and scolices consistent with Echinococcus multilocularis. A. Hooklet (100x magnification). B. Hydatid cyst with black-staining structures suggestive of degenerating hooklets. C. Zoomed detail of cyst wall. D. Degenerating hydatid cyst and hooklets. Conclusion Equivocal IgG serology does not exclude infection. History and clinical presentation are key to diagnosis, but histopathology remains the gold standard. Hydatid bone infection progresses insidiously and frequently recurs, depending upon excision and debridement. Finally, echinococcosis demands aggressive long-term therapy and surveillance. Disclosures Claudia R. Libertin, MD, Pfizer, Inc. (Grant/Research Support, Research Grant or Support)

Case: We report a case of a 71-year-old man diagnosed with high-grade undifferentiated pleomorphic sarcoma in the left thigh. He underwent partial resection of the quadriceps and proximal femoral bone, followed by reconstruction with a latissimus dorsi free muscle flap through end-to-end vascular and nerve anastomosis with the femoral vessels and a branch of the femoral nerve, respectively. Recovery of 3/5 knee extension function was achieved 3 months postsurgery without complications. Conclusion: Free neurotized latissimus dorsi muscle transfer is a successful reconstructive option to restore knee extension after quadriceps resection. Level of Evidence: Level IV.

BackgroundAdamantinomas are rare bone tumors, commonly affecting the tibia. Due to the rare nature of disease, previous studies are small or from multiple centers. The purpose of this study is to investigate outcomes of patients with adamantinoma treated in a single institution.MethodsForty‐six histological confirmed adamantinomas of the extremities were reviewed at our institution between 1939 and 2012. Follow‐up data included clinical and radiographical information focusing on complications, local recurrence, metastasis, and overall survival after the treatment. The mean follow‐up was 16 years (range 2‐42 years).ResultsThe most common location was the tibia (n = 31). Patients commonly presented with pain and swelling. The mean age was 24 years (7‐79 years). Thirty‐seven patients were treated with limb salvage. The 39% of patients required a reoperation. The 10‐year disease specific‐ and recurrence free survival was 92% and 72%, with three patients having a recurrence over 15 years postoperative. Older (> 20 years) patients and males were at increased risk of local recurrence (P < 0.05).ConclusionTreatment of adamantinoma of the long bone consists of limb‐salvage surgery. Male patients should be cautioned on their increased risk of disease recurrence, and advocate for continued surveillance of patients even greater than 15‐years postoperatively due to late tumor recurrence.

Key Clinical Message Myxoinflammatory fibroblastic sarcoma is a rare sarcoma which typically presents in the extremities and is treated by definitive surgery. In recurrent disease, the reported utilization of radiotherapy is increasing, and more modern techniques such as intensity‐modulated radiotherapy may be improving long‐term outcomes.

We report a response to pazopanib in a 69-year-old man with heavily pre-treated metastatic extraosseous Ewing sarcoma in addition to molecular profiling of his tumor. To our knowledge, this case is the earliest to demonstrate activity of an oral multi-targeted kinase inhibitor in Ewing sarcoma. This case provides rationale for adding a Ewing sarcoma arm to SARC024, a phase II study of regorafenib, another multi-targeted kinase inhibitor, in patients with liposarcoma, osteosarcoma and Ewing and Ewing-like sarcomas (NCT02048371). This national multi-institutional study is ongoing.