Abstract
Purpose: Dedifferentiated chordomas are a rare and aggressive variant of chordoma. They usually occur in recurrences or following radiotherapy. We describe the rare occurrence of three cases arising de novo within conventional chordoma.
Methods and Results: 29 cases of histopathologically verified chordoma were identified from our unit database. From these, we identified three cases of primary dedifferentiated chordoma. The study group included three men, with an average age of 58.3 years (range 57–61). Presenting features were comparable and included lower back pain and rectal discomfort, with a mass palpable per rectum. A needle biopsy was undertaken in one patient, which demonstrated evidence of a pleomorphic spindle cell tumour without evidence of chordoma. Surgical management involved subtotal sacrectomy, with complete excision achieved in two cases. Histopathological examination confirmed dedifferentiated chordoma with varying amounts of sarcomatous elements in each case. Post-operative radiotherapy was administered in two patients and chemotherapy in one patient. Two patients died at 7 and 10 months following presentation with pulmonary metastases. The third patient remains well and alive at two years follow-up. This patient had a complete excision with post-operative radiotherapy, however histopathological examination revealed only a small focus of the dedifferentiated component.
Conclusions: Dedifferentiated chordoma is a fatal tumour, with metastases and death the likely outcome. Most cases in the literature and the two cases reported in this series, uphold this ominous prognosis. However this may not always hold true. Small areas of dedifferentiation within the chordoma tumour may carry a more favourable prognosis.
The abstracts were prepared by Mr Roger Tillman. Correspondence should be addressed to BOOS at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PN
