summary Adamantinomas are rare, low-grade malignant tumors of unknown etiology that are almost always located in the diaphysis of the mid-tibia. The condition usually presents in patients who are between 20 and 40 years old with regional pain and a palpable mass. Diagnosis is made with a biopsy showing nests of epithelial-like cells arranged in palisading or glandular pattern, in a background of fibrous stroma. Treatment is usually wide-margin surgical resection. Epidemiology Incidence less than 300 cases have been documented Demographics occurs in young adults (20 - 40 years of age) Anatomic location almost always located in mid-tibia Etiology Pathophysiology unknown Associated conditions osteofibrous dysplasia historically, it was thought that osteofibrous dysplasia (OFD) was a precursor to this adamantinoma, however current studies have cast doubt on this theory Presentation Symptoms pain of months to years duration Physical exam bowing deformity or a palpable mass of tibia is common Imaging Radiographs multiple sharply circumscribed lucent lesions ("soap bubble" appearance) with interspersed sclerotic bone in mid-tibia some lesions may destroy cortex may see bowing of the tibia radiographic evolution of lesions is helpful in the diagnosis as lesions may continue to grow and erode thru the cortex unlike other primary bone tumors, adamantinoma typically shows no periosteal reaction Studies Histology biphasic contains both epithelial and fibrous mesenchymal cells nests of epithelial-like cells arranged in palisading or glandular pattern stain for keratin background of fibrous stroma Differential Osteofibrous dysplasia differentiating between osteofibrous dysplasia and adamantinoma is critical osteofibrous dysplasia is benign and treated with observation adamantinoma is malignant and treat with surgical resection Differential diagnosis of Adamantinoma Tibial diaphysis lesion Treated with wide-resection alone Adamantinoma o o Osteofibrous dysplasia o Chondrosarcoma o Parosteal osteosarcoma o Treatment Operative wide-margin surgical resection indications standard of care in most patients techniques often requires intercallary resection with allograft or intercallary megaprosthesis reconstruction as adamantinoma is a low-grade malignancy, radiotherapy and/or chemotherapy is not typically used for local control of disease Prognosis May metastasize to lungs (25%), therefore long-term followup is recommended Recurrence is uncommon with negative margin excision
QUESTIONS 1 of 8 1 2 3 4 5 6 7 8 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ12.31) A 28-year-old male presents for evaluation of leg pain. He denies trauma, and is otherwise healthy. A lateral radiograph of the affected leg is shown in Figure A. A biopsy is taken, and the low and high power histology specimens are shown in Figures B and C. Which of the following should be offered as definitive treatment of this lesion? QID: 4391 FIGURES: A B C Type & Select Correct Answer 1 Continued observation 6% (256/4581) 2 Radiation and chemotherapy 6% (279/4581) 3 Bracing to prevent tibial deformity and pathologic fracture 8% (370/4581) 4 Immediate above the knee amputation 3% (152/4581) 5 En bloc resection with wide margins followed by appropriate reconstruction 76% (3486/4581) L 2 Question Complexity B Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ11.122) A 21-year-old female presents with 7 years of leg pain and deformity. Radiographs from when she first noticed the lesion at age 14 are shown in Figures A and B. Current radiographs are shown in Figures C and D. Current MRI and histology section are shown in Figures E & F. What is the most likely diagnosis? QID: 3545 FIGURES: A B C D E F Type & Select Correct Answer 1 Osteofibrous dysplasia 25% (443/1760) 2 Adamantinoma 57% (997/1760) 3 Chronic osteomyelitis 1% (22/1760) 4 Periosteal osteosarcoma 3% (46/1760) 5 Fibrous dysplasia 14% (246/1760) L 2 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK This is an AAOS Self Assessment Exam (SAE) question. Orthobullets was not involved in the editorial process and does not have the ability to alter the question. If you prefer to hide SAE questions, simply turn them off in your Learning Goals. (SAE08PA.43) A 30-year-old woman has had pain in her right leg for the past 6 months. A lytic lesion is noted in the anterior cortex of the midtibia, extending 5 cm in length without a soft-tissue mass. A radiograph and a biopsy specimen are shown in Figures 35a and 35b. What is the preferred treatment? QID: 6304 FIGURES: A B Type & Select Correct Answer 1 Debridement and IV antibiotics 3% (19/578) 2 Wide resection of the lesion 65% (376/578) 3 Chemotherapy alone 9% (54/578) 4 Observation 14% (80/578) 5 Amputation 8% (47/578) L 4 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic (OBQ07.42) A 24-year-old male presents with pain in his tibia. Radiographs are shown in Figure A. Histology is shown in Figure B. What is the most likely diagnosis? QID: 703 FIGURES: A B Type & Select Correct Answer 1 Ewing's sarcoma 5% (42/824) 2 Adamantinoma 80% (658/824) 3 Osteosarcoma 7% (60/824) 4 Osteoblastoma 4% (30/824) 5 PNET 4% (29/824) L 1 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic
All Videos (0) Podcasts (1) Pathology⎪Adamantinoma Orthobullets Team Pathology - Adamantinoma Listen Now 8:25 min 6/16/2020 201 plays 5.0 (1)
Lytic tibial bone lesion in 72M (C2604) buddhi prasad bhandari Pathology - Adamantinoma E 6/16/2016 341 4 3