Paget's Osteosarcoma — no Cure in Sight

Purpose Paget' s osteosarcoma has a fearful reputation with a quoted survival of at best 5% at 5 years.We therefore reviewed our experience of 26 patients treated over the last 25 years using modern staging and limb salvage techniques to see if there had been any improvement in survival. Subjects: We identified 26 patients on the Royal Orthopaedic Hospital Oncological database with a diagnosis of sarcoma secondary to Paget's disease. Results: The survival rate was 53% at 1 year, 25% at 2 years and no patient survived for 5 years.The median survival was 21 months for those treated with curative intent and 7 months for those treated palliatively. Four of the five patients treated with limb-sparing surgery developed local recurrence between 5 and 12 months, the fifth died at 14 months.There was no difference in survival between amputation and limb salvage. Discussion: The development of sarcomatous change in Paget's disease is well recognised. It represents an important segment of primary bone tumours in patients over 40 years of age.The prognosis is appalling. Indeed only 15 of 368 cases (4%) from a number of historical series have survived more than 5 years. Our results are similarly disappointing with no survivors at 5 years despite modern methods of management of bone tumours.While there is no difference in local recurrence rates or survival between limb reconstruction and limb ablation the poor prognosis for both means that neither can be recommended at present. Sarcomatous change in Pagetoid bone should therefore be regarded as a different disease to primary osteosarcoma. It remains an incurable disease with a poor prognosis.


Introduction
T he developm ent of sarcom atous change in Paget's disease of the bone is well recognised. Indeed ® ve of th e ® rst 23 cases th at w ere repo r ted by Paget developed sarcom a.
T he incidence of this com plication is not known but has been reported to be between 0.7 and 15% 1± 4 Previous reports have demonstrated the very poor prognosis of Paget' s osteosarcom a w ith ver y few patients sur viving 5 years. 5± 10 We therefore reviewed our experience of 26 patients treated over the last 25 years using m odern staging and lim b salvage surger y to see if there had been any im provem ent in the prognosis.

M ethod
We identi® ed 26 patients whom had been referred for ad vice o r treatm en t o n th e R oyal O r tho p aed ic Hospital O ncological database with a diagnosis of sarco m a se co n d ar y to Paget' s d isease. E ighteen patients were m ale and eight fem ale. Their m ean age was 70 years (range 58± 89 years). Seventeen were stage 2b and 6 stage 3. The m ost com m on locations for the lesion were hum erus and pelvis w ith eight cases each.There were seven cases involving the fem ur and one case involving each of the tibia, ulna and skull. H istologically 22 of the cases had classical Paget's osteosarcom a while the rem aining four had a spindle cell sarcom a with no visib le osteoid.

Treatm ent
Eleven of the 26 patients underwent surgical resection w ith six having prim ary am putation and ® ve havin g lim b-sp arin g su rger y w ith en doprosthetic replacement. In only 2 patients was it considered appropriate to use chem otherapy. N either patient was considered to have bene® ted from chemotherapy. Five patients were treated w ith radiotherapy while 10 patients had palliative treatment only.

Results
The sur vival rate was 53% at 1 year, 25% at 2 years and no patient sur vived for 5 years, all patients' dying of m etastatic disease. The m edian survival was 21 m onths for those treated with curative intent and 7 m onths for those treated palliatively. Four of the ® ve patients treated with lim b sparing surgery developed local recurrence between 5 and 12 months, the ® fth died at 14 m onths.There was no difference in survival between am putation and lim b salvage (Fig. 1).

Discussion
The developm ent of sarcom atous change in Paget's disease is well recognised. It represents an im portant segm ent of prim ar y bone tum ours in patients over 40 years of age. T he prognosis is appalling. Indeed only 15 of 368 cases (4% ) from a num ber of historical series have survived m ore than 5 years.
O ur series is com parable to those of Greditzer, Scharjow icz and Sm ith 4±  can be considered curative. The decision as to which m ethod of surgery should be offered for the individual patient will be based on w hich is felt to give the best palliation and the best function for that individual.
Sarc om atou s change in Pag etoid bon e sho uld therefore be regarded as a different disease to prim ary osteosarcom a. It rem ains an incurable disease with a poor prognosis.