Case report 660: Adamantinoma of tibia

Adamantinomatous tumors: Long-term follow-up study of 20 patients treated at a single institution

BACKGROUND AND OBJECTIVES

Adamantinomas are primary, low-grade malignant tumors of the bone that have metastatic potential to the lungs, lymph nodes, and other regions. The rarity of this disease and its nonspecific symptoms complicate diagnosis.

MATERIALS AND METHODS

Records for 20 patients who underwent treatment for adamantinoma from 1975 to 2018 were reviewed for demographic, clinical, and pathological data, treatment details, postoperative complications, and outcomes.

RESULTS

Patients presented at a median age of 22 years (1-79 years): 14 patients had a localized primary tumor, three presented with local recurrence, and three with metastatic disease. Median tumor size was 5.7 cm (0.5-15.5 cm). Wide excision was performed primarily in 15 cases; the remaining five patients underwent intralesional curettage. At a median follow-up of 7.3 years, 14 patients had no evidence of disease; two patients were alive with disease, and four patients died from the disease. Local recurrence and distant metastasis occurred at a median of 11.4 years (6 month-19 years) and 15.8 years (4 month-23 years) after diagnosis.

CONCLUSIONS

Adequate histopathological diagnosis is crucial to avoid misdiagnosis of this rare tumor. Local and distant recuAbs_Para_meprrence can occur more than 20 years after the initial diagnosis. Life-long follow-up with clinical examination and imaging is required.

Long-Term Follow-Up of Adamantinoma of the Tibia Complicated by Metastases and a Second Unrelated Primary Cancer: A Case Report and Literature Review

Adamantinoma is a rare, low-grade malignant tumor of the bone which grows slowly and typically occurs in the diaphysis of long bones, particularly in the tibia. Adamantinomas have the potential for local recurrence and may metastasize to the lungs, lymph nodes, or bone. We report a case of a 14-year-old female with a tibial adamantinoma who underwent wide resection with limb salvage and has subsequently been followed up for 18 years. The patient went on to have both a local soft tissue recurrence 5 years after the resection and metastases to both an inguinal lymph node and the right lower lobe of the lung 8 years after that recurrence, all of which have been treated successfully with marginal resections. Unique to this case, the patient was also incidentally found to have chromophobe-type renal cell carcinoma when undergoing a partial nephrectomy to resect a presumed metastasis of her adamantinoma. Genetic testing has not revealed any known genetic predisposition to cancer.

Adamantinoma, osteofibrous dysplasia and differentiated adamantinoma

For just over 100 years, adamantinoma has been recognized as a primary bone tumor with epithelial characteristics and predominantly involving the tibia. Osteofibrous dysplasia is a fibro-osseous lesion also predominantly confined to the tibia with radiologic features similar to those of adamantinoma. This lesion has been shown by immunohistochemical studies to frequently contain cytokeratin-positive epithelial cells. More recently, a third group of cases with clinical and radiologic features similar to those of osteofibrous dysplasia have demonstrated more overt strands of epithelial cells within a fibro-osseous background and have been categorized as "differentiated", "regressive", "juvenile intracortical" or "osteofibrous dysplasia-like" adamantinoma. Cytokeratin subset immunohistochemical stains and cytogenetic studies performed in recent years suggest a common histogenesis for these three entities. This article reviews the clinical, radiologic and pathologic features of these entities as well as their prognostic significance. It also reviews the results of the immunohistochemical and cytogenetic studies which establish a common histogenetic relationship.

Adamantinoma of the appendicular skeleton in children

The 260 cases of adamantinoma described in the world literature have been reviewed. Case histories of 60 patients up to the age of 16 years mirror those of adults. The mortality rate is 20% in children and adults. Wide excision with bone grafting is the ideal treatment for patients under 16 years.

Osteofibrous dysplasia: clinicopathologic study of 80 cases

A thorough review of the clinical, radiologic, and histologic features of 80 cases of long bone osteofibrous dysplasia is presented. Of the six cases of osteofibrous dysplasia immunostained with a cytokeratin antibody, two were cytokeratin positive; however, the five cases of fibrous dysplasia that were stained were all negative. Follow-up (mean, 5.4 years; range, 1 month to 31 years) data were available for 41 cases (51%). From the consultation series nine of the 18 patients studied had recurrences, regardless of the different treatment regimens. The average recurrence interval in these patients was 2.7 years. Two patients had incomplete excision and six had biopsy only. All eight of these patients had residual tumors. Among the 16 Mayo Clinic patients, one had recurrence 5 years after the initial treatment. In two cases, 7-year-old and 6-year-old boys, histologic maturation to fibrous dysplasia was observed 4 and 10 years later, respectively. Adamantinoma has not developed in any of the 41 cases of osteofibrous dysplasia for which we have follow-up information. It seems clear that osteofibrous dysplasia does not progress to adamantinoma. Our study suggests that osteofibrous dysplasia is probably a variant of fibrous dysplasia, as demonstrated by the maturation of two lesions of osteofibrous dysplasia to fibrous dysplasia. Surgical treatment may be appropriate in cases with an extensive lesion, pseudoarthrosis, and accentuated tibial bowing. The overall prognosis is good, even with recurrence.

Lesions of juxtacortical origin (surface lesions of bone)

A large variety of tumor and tumor-like conditions have been shown to originate from the surface of bone (Table 1). Most surface lesions are associated with periosteal reaction. The periosteum is a multipotential membrane. Its cellular composition may give rise to a variety of both neoplasms and tumor-like conditions. To avoid misinterpretation, the orthopedist, radiologist, and pathologist should be familiar with the entire spectrum of surface lesions. A better understanding of the natural history and biological behavior at different lesional maturity stages and correlation of the history with the radiographic and pathological findings is essential to establish the correct diagnosis. A history of injury or blunt trauma is very important. A stress fracture may produce a periosteal reaction acd callus that can be difficult to distinguish from osteosarcoma. In this review article, the authors wish to describe and define each term by its anatomy and radiographic features while discussing the entire spectrum of surface lesions. All the illustrative cases in this review article have been proven histologically.