The purpose of this retrospective study was to differentiate
between the MRI features of normal post-operative change and those
of residual or recurrent disease after intralesional treatment of
an atypical cartilage tumour (ACT)/grade I chondrosarcoma. We reviewed the case notes, radiology and histology of 75 patients,
who had been treated for an ACT/grade I chondrosarcoma by curettage,
phenolisation and bone allografting between 1994 and 2005. The first
post-operative Gd-enhanced MRI scan was carried out within one year
of surgery. Patients had a minimum of two scans and a mean follow-up
of 72 months (13 to 169). Further surgery was undertaken in cases
of suspected recurrence.Aims
Patients and Methods
Giant cell tumours (GCT) of the synovium and
tendon sheath can be classified into two forms: localised (giant
cell tumour of the tendon sheath, or nodular tenosynovitis) and
diffuse (diffuse-type giant cell tumour or pigmented villonodular
synovitis). The former principally affects the small joints. It
presents as a solitary slow-growing tumour with a characteristic
appearance on MRI and is treated by surgical excision. There is
a significant risk of multiple recurrences with aggressive diffuse
disease. A multidisciplinary approach with dedicated MRI, histological assessment
and planned surgery with either adjuvant radiotherapy or systemic
targeted therapy is required to improve outcomes in recurrent and
refractory diffuse-type GCT. Although arthroscopic synovectomy through several portals has
been advocated as an alternative to arthrotomy, there is a significant
risk of inadequate excision and recurrence, particularly in the
posterior compartment of the knee. For local disease partial arthroscopic
synovectomy may be sufficient, at the risk of recurrence. For both
local and diffuse intra-articular disease open surgery is advised
for recurrent disease. Marginal excision with focal disease will
suffice, not dissimilar to the treatment of GCT of tendon sheath.
For recurrent and extra-articular soft-tissue disease adjuvant therapy,
including intra-articular radioactive colloid or moderate-dose external
beam radiotherapy, should be considered.
Low-grade surface tumours of bone may theoretically be treated by hemicortical resection, retaining part of the circumference of the cortex. An inlay allograft may be used to reconstruct the defect. Since 1988 we have performed 22 hemicortical procedures in selected patients with low-grade parosteal osteosarcoma (6), peripheral chondrosarcoma (6) and adamantinoma (10). Restricted medullary involvement was not a contraindication for this procedure. There was no evidence of local recurrence or distant metastasis at a mean follow-up of 64 months (27 to 135). Wide resection margins were obtained in 19 patients. All allografts incorporated completely and there were no fractures or infections. Fractures of the remaining hemicortex occurred in six patients and were managed successfully by casts or by osteosynthesis. The functional results were excellent or good in all except one patient. Hemicortical procedures for selected cases of low-grade surface tumours give excellent oncological and functional outcomes. There was complete remodelling and fewer complications when compared with larger intercalary procedures. The surgery is technically demanding but gives good clinical results.
