Osteofibrous Dysplasia-like Adamantinoma Mimicking Bone Metastasis in a Patient With Rectosigmoid Cancer

@#A patient with underlying rectosigmoid cancer presented with solitary bone lesion at left tibia. Eventhough, solitary bone metastasis particularly in the appendicular skeleton is rare in rectosigmoid cancer, it remained as the most likely initial diagnosis. However, after further characterisation by various imaging modalities and subsequent biopsy, the lesion proved to be an osteofibrous dysplasia like-adamantinoma (OFD-like adamantinoma), which is a subtype of adamantinoma. Being a rare primary bone tumour, adamantinoma and its subtypes are infrequently thought of in the initial working diagnosis of a patient with known malignancy who presents with solitary bone lesion. We present here a case of OFD-like adamantinoma in a patient with underlying rectosigmoid cancer, which mimic a metastastic bone lesion.

An unusual case of adamantinoma of long bone

Adamantinoma of the long bones is an exceedingly rare and slow-growing tumor that affects the diaphysis of long bones, particularly the tibia. Based on the pattern of the epithelial cell component and the presence or absence of the osteofibrous dysplasia-like element, several histological variants have been described, such as (i) tubular (the most frequent), (ii) basaloid, (iii) squamous, (iv) spindle variant, (v) osteofibrous dysplasia -like variant, and (vi) Ewing's sarcoma - like adamantinoma (the least frequent). The diagnosis may be challenging since this tumor may be mistakenly interpreted as carcinoma, myoepithelial tumor, osteofibrous dysplasia, and vascular tumor. We report the case of a 41-year-old male who presented with swelling over the right leg associated with pain. The X-ray showed a lytic lesion of the right-sided tibia. The diagnosis of adamantinoma was made based on the clinico-radiological, histomorphology, and immunohistochemical findings. Histologically, classic adamantinoma is a biphasic tumor characterized by epithelial and osteofibrous components in varying proportions and differentiating patterns. The diagnosis can be confirmed by immunohistochemistry for demonstrating sparse epithelial cell nests when the radiological features are strongly consistent with adamantinoma. This case is highlighted because the epithelial component can lead to a misdiagnosis, particularly when the clinico-radiological features are overlooked. Adamantinoma of long bones has the potential for local recurrence and may metastasize to the lungs, lymph nodes, or other bones. The prognosis is good if early intervention is taken.

Clinicopathological observation of adamantinoma of long bone / 中华病理学杂志

Objective@#To investigate the clinicopathological features and differential diagnosis of adamantinoma of long bone.@*Methods@#Seven cases of adamantinoma on long bone were selected at Jiangsu Province People′s Hospital from June 2012 to May 2018. Clinicopathologic details, immunohistochemical and molecular analysis were performed,and the relevant literature reviewed.@*Results@#There were 6 males and 1 female patients,age ranging from 21 to 60 years (mean 38 years). Six cases were on the right side and one case was on the left; in five cases the tumors arose from tibia, one from patella and one from humerus. Microscopically,tumour cells were mainly composed of spindle cells arranged in bundles or braids,with irregular epithelial island. Immunohistochemically,the epithelial island expressed high molecular weight cytokeratin but not CK8/18. Both epithelial and spindle components expressed vimentin. One case that was microscopically similar to intraosseous synovial sarcoma did not show SYT gene rearrangement. Clinical follow-up was available for five patients: one patient had axillary metastases seven months after operation, one patient had recurrence 34 months after surgery, 3 patients were uneventful with follow up duration from half a month to 32 months.@*Conclusion@#Adamantinoma occurring in long bones is very rare. The correct diagnosis requires adequate sample selection, careful morphologic observation, immunohistochemistry and molecular genetics.

Tibial adamantinoma: analysis of seven consecutive cases in a single institution / Adamantinoma da tíbia: análise de sete casos consecutivos em uma única instituição

ABSTRACT Objective: Adamantinoma accounts for less than 1% of the primary bone neoplasms. The tibia is the most affected bone and it is predominant in male patients between the second and third decades of life. The objective of this study is to obtain epidemiological and clinical information on patients with adamantinoma of the tibia treated surgically between 1989 and 2016. Methods: Retrospective series of seven patients diagnosed with adamantinoma of the tibia that underwent surgery at the orthopedic oncology service of our hospital. The information was obtained from the medical records and histopathological reports of our institution. Results: A total of 2870 medical records with histological reports were evaluated. Seven cases of adamantinoma of the tibia were included. The mean age was 28.5 (17-49) years. We found a predominance of females (71.4%) and the most affected side was the left one, with four cases (57.1%). The biopsy revealed bone adamantinoma in four (57.1%) patients, while the diagnosis of the other patients was confirmed after the histological examination of the surgical specimen. All the patients underwent surgery as definitive treatment. No positive margins were reported. No local recurrence (LR) was reported and two patients had distant metastasis (DM). Conclusion: The prognosis of survival in cases of adamantinoma of the tibia is high. The rates of LR and DM were low. Surgical treatment with extensive tumor resection is the treatment of choice. Level of Evidence IV, Case Series.

RESUMO Objetivo: O adamantinoma representa menos de 1% das neoplasias ósseas primárias. Afeta predominantemente a tíbia, em pacientes do sexo masculino entre a segunda e terceira décadas da vida. O objetivo deste trabalho é obter informação epidemiológica e clínica dos pacientes com adamantinoma da tíbia, tratados mediante cirurgia entre 1989 e 2016. Métodos: Série retrospectiva de sete pacientes com diagnóstico de adamantinoma da tíbia, tratados cirurgicamente no serviço de oncologia ortopédica do nosso hospital. A informação foi obtida dos relatos clínicos e patológicos do instituto. Resultados: Um total de 2870 prontuários com relatos anatomopatológicos foram revisados. Sete casos de pacientes com adamantinoma na tíbia foram encontrados. A média de idade foi de 28,5 anos (17-49). Encontramos predominância do sexo feminino (71,4%). O lado mais afetado foi o esquerdo, com quatro (57,1%) casos. A biópsia diagnosticou adamantinoma em 57,1% dos casos e o diagnóstico dos outros casos foi definido após exame da peça cirúrgica. Todos os pacientes receberam tratamento cirúrgico como terapia definitiva. Não foram reportadas margens comprometidas. Nenhum paciente apresentou recorrência local (RL). Dois pacientes apresentaram metástase à distância (MD). Conclusão: O prognóstico de sobrevida do adamantinoma da tíbia é alto. Apresenta taxas baixas de RL e MD. A cirurgia com ampla ressecção do tumor é o tratamento de escolha. Nível de Evidência IV, Série de Casos.

Adamantinoma de tibia en estadio temprano en adulto: reporte de caso / Adamantinoma of early stage in adult tibia: case report

El adamantinoma es un tumor maligno de bajo grado, bifásico, frecuentemente localizado en diáfisis tibial, y que comprende el 0,4% de todos los tumores óseos primarios. Debido a la rareza de esta entidad y a su similitud con lesiones benignas, su diagnóstico a veces se retrasa. Presentamos el caso de una paciente mujer de 38 años con tumoración dolorosa en pierna izquierda de 2 años de evolución, con estudios radiológicos e histopatológicos que confirmaron el diagnostico en estadio temprano.

Adamantinoma is a low-grade, biphasic malignant tumor, frequently located in tibial diaphysis, and comprising 0.4% of all primary bone tumors. Due to the rarity of this entity and its similarity with benign lesions, its diagnosis is sometimes delayed. We present the case of a 38-year-old female patient with a painful tumor in the left leg of 2 years of evolution, with radiological and histopathological studies that confirmed the diagnosis in the early stage.

Adamantinoma de la tibia / Adamantinome du tibia / Adamantinoma of the tibia

El adamantinoma es un tumor maligno de origen epitelial con una frecuencia de aparición escasa. Con este artículo se pretende describir la conducta y evolución de un paciente portador de adamantinoma de la tibia asociado a infección pulmonar y ósea por Mycobacterium avium. Se presenta un paciente masculino de 43 años de edad con el diagnóstico de adamantinoma, localizado en el tercio medio-inferior de la tibia derecha. Los hallazgos clínicos, imaginológicos e histopatológicos permiten llegar al diagnóstico de un adamantinoma del esqueleto apendicular. Se realizó la exéresis de la tumoración y relleno con cemento quirúrgico. Doce meses después del tratamiento aparecieron signos clínicos y radiográficos de recidiva tumoral y fue necesaria la amputación infratuberositaria de la pierna derecha. Además, se observaron lesiones fibroquísticas en el vértice del pulmón izquierdo relacionadas con Mycobacterium avium. Luego de un seguimiento por dos años, se observaron múltiples nódulos metastásicos en ambos campos pulmonares(AU)

Adamantinoma is an epithelial-origin malignant tumor with uncommon frequency of appearance. This article aims to describe the behavior and evolution of a patient with adamantinoma of the tibia associated with pulmonary and bone infection by Mycobacterium avium. We present a 43 years old male patient with the diagnosis of adamantinoma. This adamantinoma was located in the middle-lower third of the right tibia. The clinical, imaging and histopathological findings allowed to reach the diagnosis of adamantinoma of the appendicular skeleton. The excision of the tumor and filling with surgical cement was performed. Twelve months after the treatment, clinical and radiographic signs showed tumor recurrence. The infratuberosal amputation of the right leg was necessary. In addition, fibrocystic lesions were observed at the apex of the left lung related to Mycobacterium avium. After a two-year follow up, multiple metastatic nodules were observed in both lung fields(AU)

L'adamantinome est une tumeur maligne assez rare d'origine épithéliale. Le but de cet article est de décrire le comportement et l'évolution d'un patient atteint d'un adamantinome au niveau du tibia, associé à une infection pulmonaire et osseuse par Mycobacterium avium. Le cas d'un patient âgé de 43 ans, diagnostiqué d'un adamantinome localisé dans le tiers moyen inférieur du tibia droit, est présenté. Les observations cliniques, histopathologiques et d'imagerie ont permis de confirmer le diagnostic d'un adamantinome du squelette appendiculaire. On a effectué l'exérèse de la tumeur et le remplissage à ciment chirurgical. Douze mois après ce traitement, des signes cliniques et radiographiques d'une récidive tumorale ont apparu, et une amputation infratubérositaire de la jambe droite a été nécessaire. On a aussi trouvé des lésions fibrokystiques sur l'apex du poumon gauche, associées à Mycobacterium avium. Après un suivi de deux ans, on a rencontré plusieurs nodules métastatiques dans tous les deux côtés de la région pulmonaire(AU)

Adamantinoma de tibia: manejo quirúrgico con aloinjerto intercalar. A propósito de un caso / Adamantinoma of tibia: Surgical management with intercalary allograft. Report of a case

El adamantinoma es un tumor maligno bifásico que comprende el 0,4% de todos los tumores óseos primarios y el 23% comienza con fracturas patológicas asociadas a traumatismos ocurridos meses o años antes. Presentamos el caso de una paciente de veinte años de edad quien comienza con fractura patológica de la tibia derecha por un trauma de baja energía, con estudios radiológicos e histopatológicos que confirmaron la presencia de un adamantinoma. Fue manejado quirúrgicamente mediante resección amplia del segmento tumoral y reconstrucción con aloinjerto intercalar de tibia fijado con un clavo endomedular de estabilidad multidireccional sustentado con una placa antirrotatoria proximal. Los resultados radiológicos y clínicos fueron satisfactorios.

The adamantinoma is a biphasic malignant tumor comprising 0.4% of all primary bone tumors and 23% debuts with pathological fractures associated with trauma that occurred months or years earlier. We report the case is presented of a twenty-year-old woman that debuted with a pathological fracture of the right tibia with a low-energy trauma. The radiological and histopathological studies confirmed the presence of an adamantinoma. This was treated surgically by wide resection of the tumor and reconstructed with an intercalary allograft bone segment that was fixed with a tibial intramedullary multidirectional antirotatory stability nail sustained further by a proximal plate. The radiological and clinical results were satisfactory.

Adamantinoma en pediatría: Presentación de caso / Pediatric adamantinoma: Case report

El adamantinoma es un tumor primario de los huesos largos, que afecta principalmente la diálisis de la tibia, y es extremadamente raro en pediatría. Se presenta a partir de la segunda década de vida, con un ligero predominio en el sexo masculino. Se trata de un tumor de bajo grado, con alta agresividad a nivel local y bajo índice de metástasis y recurrencia una vez resecado en forma completa. Su diagnóstico resulta difícil, no solo por tratarse de una patología poco frecuente en pediatría, sino también por la dificultad para el diagnóstico diferencial con otras lesiones benignas. Presentamos el caso de un paciente de 15 años, con una tumoración indolora de larga evolución en la tibia distal, cuyo diagnóstico fue confirmado histológicamente con la pieza de amputación, ya que los estudios complementarios y las dos biopsias iniciales no fueron concluyentes. Aunque la mayoría de la bibliografía publicada consta de reportes de casos, y muy pocos en pacientes pediátricos, es de común acuerdo la dificultad para arribar al diagnóstico de adamantinoma.

Adamantinoma is a primary tumor of long bones, which affects mainly the shaft of the tibia, and is extremely rare in pediatrics. It frequently presents during the second decade of life, with a slight predominance in males. It is a low grade tumor, with local aggressiveness and low rate of metastasis and recurrence once it is completely removed. Its diagnosis is difficult, not only because it is a rare disease in children, but also because of the difficulty in the differential diagnosis with other benign lesions. We report the case of a 15-year-old patient with a painless swelling of the distal tibia, whose diagnosis was confirmed with the piece of amputation, as imaging features and both initial biopsies were not enough to achieve diagnosis. Though most of the literature consists of case reports, and very few in pediatric patients, they all agree on the difficulty in achieving the diagnosis of adamantinoma.

Adamantinoma de ossos longos / Adamantinoma of the long bones

OBJETIVOS: Estudar retrospectivamente 18 casos de pacientes com adamantinoma de ossos longos, todos localizados na tíbia; ressaltar a importância da biópsia e a correlação com métodos de imagem para diagnóstico diferencial com osteofibrodisplasia e displasia fibrosa; tecer considerações sobre a natureza do adamantinoma de ossos longos, cujo nome deve-se à analogia histológica com o adamantinoma (ameloblastoma) da mandíbula. MÉTODOS: Foram analisados o quadro clínico, imagens e exames anatomopatológicos complementados com imunohistoquímica e a evolução dos pacientes. Todos foram submetidos a tratamento cirúrgico, 17 com "tibialização" da fíbula e os demais com amputação. RESULTADOS: A evolução pós-cirúrgica mostrou-se imprevisível e não relacionada com os aspectos clínicos ou histopatológicos. Dois pacientes evoluíram com metástases pulmonares e morreram. Seis não tiveram recidivas ou metástases e estão clinicamente curados. Os demais, após alta hospitalar não retornaram à consulta. CONCLUSÕES: Trata-se de rara neoplasia constituída por estruturas epiteliais e mesenquimais que devem ser diagnosticadas com precisão, antes de qualquer procedimento. O tratamento é cirúrgico com ressecção do tumor com boa margem oncológica. O comportamento biológico é variável e imprevisível.

OBJECTIVE: To make a retrospective study of 18 cases of patients with adamantinoma of the long bone, all of them located in the tibia; to point to the relevance of biopsy and the correlation with imaging methods in order to have a differential diagnosis with osteofibrous dysplasia and fibrous dysplasia; to comment on the nature of long bone adamantinoma, whose name is due to the histological analogy with the adamantinoma (ameloblastoma) of the jaw. METHODS: A review was made of the clinical condition, images, and anatomopathological exams supplemented with immunohistochemical essays, and the evolution of the patients. All of them were submitted to surgical treatment, 17 with "tibialization" of the fibula and the others with amputation. RESULTS: The post-surgical evolution showed to be unpredictable and not related to clinical or histopathological aspects. Two patients had an evolution with lung metastasis and died. Six did not present recurrent disease or metastases, and are clinically cured. The others, after being released from hospital, did not return for consultation. CONCLUSIONS: This is a rare neoplasia made of epithelial and mesenchymal structures that must be accurately diagnosed before any procedure is attempted. Treatment is surgical, with tumor resection with a good oncologic margin. The biological behavior is varied and unpredictable.

Caso raro de pneumotórax: adamantinoma metastático / A rare case of pneumothorax: metastatic adamantinoma

Descrevem-se dois casos de metástases pulmonares de adamantinoma de ossos longos, o qual é uma neoplasia óssea de baixo grau que raramente metastatiza. Nos dois casos a apresentação clínica das metástases se deu por pneumotórax espontâneo secundário a escavação tumoral, fenômeno descrito em apenas três dos trabalhos consultados na literatura. São descritos os achados clínicos, radiológicos e anatomopatológicos, bem como os procedimentos adotados nos dois casos.

Here, we describe two cases of lung metastasis of adamantinoma of long bones, a low-grade bone neoplasm that rarely metastasizes. In both cases, the clinical presentation of the metastases was characterized by spontaneous pneumothorax secondary to tumor cavitation, a phenomenon described in only three of the studies reviewed in the literature. Clinical, radiological, and anatomopathological findings, as well as the procedures adopted in the two cases, are described.

Treatment of Osteofibrous Dysplasia and Associated Lesions

PURPOSE: To report long term treatment outcomes of osteofibrous dysplasia and association with adamantinoma. PATIENTS AND METHODS: From January 1984 to July 2001, 14 patients with osteofibrous dysplasia were followed for an average of 108 months (78 to 260 months). Our patient group consisted of 6 men and 8 women, with a mean age of 13.9 years (2 to 65 years). We reviewed the clinical and pathological features of all 14 patients. RESULTS: Thirteen patients had a lesion in the tibia, while one patient had lesions in both the tibia and the fibula. Initial treatments were observation after biopsy (6 patients), curettage with or without a bone graft (3 patients), resection followed by a free vascularized fibular bone graft (4 patients), or resection and regeneration with the Ilizarov external fixation (1 patient). Curettage was performed on 6 patients due to recurrence or progression after the initial treatment. Among these patients, one was diagnosed with AD from the biopsy of the recurrent lesion. This patient was further treated by segmental resection and pasteurization. After the initial pathology slides of the 13 patients were reviewed with immunohistochemical cytokeratin staining, one patient diagnosis was changed from osteofibrous dysplasia to osteofibrous dysplasia-like adamantinoma. CONCLUSION: Some patients with osteofibrous dysplasia require close observation because of the high association risk between osteofibrous dysplasia and adamantinoma, Immunohistochemical staining may be helpful in differentiating these two diagnoses.

Osteofibrous Dysplasia-Like Adamantinoma: A Case Report with its Immunohistochemical and Ultrastructural Studies

Osteofibrous dysplasia (OFD)-like adamantinoma is a rare skeletal tumor that is characterized by the predominant OFD-like pattern with scattered epithelial nests. Adamantinoma shares clinical features (the majority of lesions in the tibia and the prevalent age group), radiologic findings (radiolucency with sclerotic shadow), and pathologic similarities (particularly the presence of scattered cytokeratin-positive stromal cells) with OFD. We describe a case of OFD-like adamantinoma. Epithelial cell nests express the epithelial membrane antigen, pancytokeratin, CK14, and collagen type IV. Ultrastructurally, the oval to spindle cells in the epithelial foci had abundant tonofilaments, and well-formed desmosomes with dense plaques, of which well preserved desmosomes are demonstrated for the first time in OFD-like adamantinoma. These immunohistochemical and ultrastructural findings further support that the origin of epithelial cells of classic and OFD-like adamantinoma are epithelial cells transformed from fibroblastic cells in the proliferating osteofibrous tissue.

Adamantinoma of tibia with predominant features of fibrous dysplasia:a case report

We report a case of adamantinoma of the tibia resembling fibrous dysplasia. The patient was a 55-year-old male, and complained of pain in the right lower leg. Roentgenographs showed a well demarcated osteolytic lesion with small foci of calcification and septation within the diaphysis of the distal tibia. The cortex was partially disrupted. Histologically, initial biopsy specimen showed fibrous connective tissue and trabeculae of immature woven bone, strongly suggestive of fibrous dysplasia. The lesion recurred and the second biopsy revealed nests of spindle cells and tubular epithelial structures embedded in granulation type-fibrous tissue. Immunohistochemically, both the nests of spindle cells and the tubular structures gave a positive reaction for cytokeratin. The present case emphasizes once again that histological diagnosis of fibrous dysplasia of the tibia should be made carefully with exclusion of the possibility of adamantinoma.

ADAMANTINOMA OF LONG BONES / 西安交通大学学报(医学版)

Adamantinoma of long bones is very rare. Approximately more than 100 cases have been reported in the literature, but only 3 cases in this country. This paper reports 2 cases adamantinoma of the tibia.The pathological characteristics of the tumor are: 1) basal-cell carcinomatous, 2) glandular, 3) tubular ( of varying sizes), and 4 ) squamous metaplasia. The origin of the tumor in controversial. We support the theory of its epithelial origin.