Diaphyseal Medullary Stenosis with Malignant Fibrous Histiocytoma

Summary
Description

Diaphyseal Medullary Stenosis with Malignant Fibrous Histiocytoma (Hardcastle's syndrome) is a rare, autosomal dominant bony dysplasia characterized by symmetric diaphyseal medullary stenosis of long bones and a very high risk of development of Malignant Fibrous histiocytoma.

People and Age
This is an inherited condition that is seen in four or five families worldwide.
Complete Information on this Tumor
Introduction and Definition

Hardcastle's syndrome is a rare, autosomal dominant bony dysplasia characterized by symmetric diaphyseal medullary stenosis of long bones and a very high risk of development of Malignant Fibrous histiocytoma.

The authors of this site, in cooperation with Dr. Martignetti, have an interest in this disorder. If you or your family member is affected by this disorder, please contact the authors of this site.

This rare disorder has been reported in four or five families worldwide. It is inherited as an autosomal dominant trait. Characteristic findings become visible on radiographs in early adult years. Transformation into Malignant Fibrous histiocytoma occurs in approximately 35 percent. Insufficiency fractures can occur in affected long bones. Following treatment, healing is slow and nonunion may result.

The authors have experience with affected individuals from two of the five known families. One individual has suffered traumatic fractures of the femur and tibia. Although the involved bone appears very dense on plain radiographs, the bone is more likely to fracture than normal bone.

Incidence and Demographics
This is an inherited condition that has been seen in four or five families worldwide.
X-Ray Appearance and Advanced Imaging Findings
Radiographs show thickening of the cortex, with irregularity and loss of distinction of the endosteal surface. There may be small lucent or lytic areas within or adjacent to the cortex, which may appear to permeate a region of the bone. The metaphyseal area has striated densities that may be seen as confluent fibro-osseous bands on axial imaging. Larger seemingly lytic areas may be seen, although these may areas of normal density surrounded by more sclerotic areas. The diffuse changes seen throughout multiple long bones have the appearance of "worm-eaten wood". Fractures occur with relatively minor trauma through affected bone, and healing is slow and incomplete. Visible fracture lines persist years after surgical stabilization.

Bone scan does not show abnormal uptake in all affected areas, and uptake in areas of recent fracture is much more modest than expected.

CT scan shows the densification of the medullary space and confluent striations.
Treatment Options for this Tumor
Treatment should be based on: 1) Avoidance of pathological fracture by appropriate activity modifications. 2) Treatment of pathologic fracture, with appropriate biopsy sampling of fracture areas to detect malignancy. Internal fixation, preferably by intramedullary rodding, is best. It should be expected that the rods will stay in permanently due to the lack of complete healing. 3) Ongoing monitoring for malignant transformation. One approach is to educate the patient about reporting any signs and symptoms of this event, coupled with regular scheduled exams and plain radiographs of affected bones. Serial bone scanning has been considered, but the potential carcinogenic effects of the radioisotopes are of concern in these individuals. No established monitoring protocol has been proposed, but similar monitoring is routine for other genetically-based disorders where there is an increased cancer risk.