Masazumi Hirata

Use of purified beta-tricalcium phosphate for filling defects after curettage of benign bone tumours

Fifty-three patients with benign bone tumours were treated with curettage and filling with a purified beta-tricalcium phosphate (β-TCP). Recurrences occurred in two cases. There was neither a postoperative infection nor adverse reaction due to the material. Postoperative fractures did not occur in any patients. Radiographically, complete resorption of the material and bone remodelling were achieved in 23 cases (43%). Of these 23 cases, there was a statistical correlation between the filling volume and the time taken for complete resorption (p<0.05). We concluded that purified β-TCP was an ideal bone graft substitute for the treatment of benign bone tumours because of its good biocompatibility and resorption characteristics.Résumé53 patients présentant une tumeur bénigne des os ont été traités par curetage et greffe par du beta-tricalcium phosphate (β-TCP) pur. La récidive de la tumeur n’a été observée que dans deux cas. Il n’y a eu aucune infection et aucune réaction négative dues au matériel. Nous n’avons pas constaté de fractures post-opératoires. Sur le plan radiographique, nous avons assisté à une résorption complète de la tumeur et remodelage osseux chez 23 patients (43%). Pour ces 23 patients, il existe une corrélation statistique non significative entre le volume du substitut et le temps pour sa complète résorption (p<0.05). Nous pouvons en conclure que le β-TCP est un substitut osseux idéal pour le traitement des tumeurs osseuses bénignes qu’il présente une bonne bio compatibilité et des caractéristiques satisfaisantes en terme de résorption.

More than 10 years of follow-up of two patients after total femur replacement for malignant bone tumor

Abstract One patient with osteosarcoma and one with Ewing’s sarcoma of the femur were in 1987 and 1988 treated with prosthetic replacement of the femur and chemotherapy. There has been no loosening of the prostheses and no recurrence of the tumor. The patients have maintained 60% and 63% limb function scores evaluated by ISOLS criteria.Résumé Deux patients, l’un avec un ostéosarcome, l’autre avec un sarcome d’EWING, furent opérés en 1987–1988 avec remplacement prothétique du fémur, associéà une chimiothérapie. Ces patients ont été suivis sans qu’il soit noté de récidive. Il n’y a pas de descellement, ni de luxation de la prothèse. Un score fonctionnel évalué selon les critères de l’ISOLS, montre une conservation de 60% et 63% de la fonction du membre inférieur.

Clinical outcome of total scapulectomy in 10 patients with primary malignant bone and soft-tissue tumors.

Limb reconstruction after total scapulectomy for malignant bone and soft‐tissue tumors around the scapula is difficult. This study was undertaken to clarify the clinical results of total scapulectomy in patients with malignant bone and soft‐tissue tumors around the shoulder girdle in our institute between 1984 and 1998.

Prognostic significance of DNA ploidy pattern in osteosarcomas in association with chemotherapy.

In this study, we analysed the DNA ploidy of osteosarcomas at biopsy and attempted to clarify the relationship between DNA ploidy pattern and prognosis. Thirty patients with non-metastatic osteosarcoma of an extremity were studied. All underwent intensive chemotherapy with doxorubicin, cisplatin and methotrexate, in addition to wide tumor resection. DNA ploidy was detected by DNA cytofluorometry, using isolated and smeared cells of biopsied tumor tissue. Twelve tumors showed a diploid ploidy pattern and 18 showed a non-diploid pattern such as aneuploidy (15 tumors) and euploid-polyploidy (3 tumors). The event-free survival rate at 9 years was 63.5% in non-diploid osteosarcoma patients and 13.3% in diploid osteosarcoma patients. There was a statistically significant difference between the two groups (P = 0.0278). These results lead us to conclude that a non-diploid osteosarcoma may be more sensitive to chemotherapy than a diploid tumor.

Relationship between P-glycoprotein positivity, doxorubicin binding ability and histologic response to chemotherapy in osteosarcomas

We previously reported that the doxorubicin binding ability detected by the doxorubicin (adriamycin) binding assay was closely correlated with the chemosensitivity of human osteosarcomas. In this study, we undertook to clarify the relationship between P-glycoprotein positivity (%PPG) and doxorubicin binding ability (%DB) in human osteosarcomas in order to determine which is a more sensitive index of histologic response to chemotherapy. Ten primary osteosarcomas were analyzed by the doxorubicin binding assay and by immunofluorescence to detect cellular P-glycoprotein positivity. Three good responders to chemotherapy containing doxorubicin showed a %DB greater than 90% (average: 96.43%), whereas the seven poor responders had values less than 80% (average: 35.31%). The difference between the two groups was statistically significant (P = 0.0167). However, the average %PPG of the three good responders was 6.73%, whereas the %PPG of the seven poor responders was 14.27%. There was no significant difference in %PPG between the two groups (P = 0.3051). No negative correlation between the %DB and the %PPG of all osteosarcomas (r = 0.536, P = 0.1104) was found, although there was a trend that those tumors with a high %PPG showed a low %DB. These results suggest that osteosarcomas showing a low %DB and %PPG with poor response to chemotherapy, may have multidrug resistance mechanisms other than P-glycoprotein. Therefore, we conclude that doxorubicin binding ability, which reflects all of the doxorubicin-resistant mechanisms, was more sensitive than P-glycoprotein positivity in predicting the chemosensitivity of human osteosarcoma.

Cytofluorometric DNA ploidy analysis in giant cell tumor of bone: histologic and prognostic value

DNA ploidy analysis by DNA cytofluorometry was performed on 41 tumors obtained from 37 patients with primary giant cell tumor of bone (GCT). Histologically, 26 of the tumors from primary or recurrent lesions were evaluated as grade I, and 13 tumors as grade II. Among the 33 primary GCT patients, 4 patients had local recurrence or pulmonary metastasis. The DNA ploidy pattern and the percentage of hyperdiploid cells showing a greater DNA content than diploid cells, were obtained from DNA cytofluorometry. All of the 33 primary tumors were diploid. Of 6 recurrent tumors, 4 were diploid and 2 were euploid-polyploid. One of the two pulmonary metastatic tumors was diploid, but another that demonstrated a malignant transformation to malignant fibrous histiocytoma was aneuploid. The percentage of hyperdiploid cells was significantly different between primary and recurrent tumors (P = 0.0188) and between grade I and grade II tumors (P = 0.0052), while there was no difference between primary tumors in the cases that recurred or metastasized and those that did not. Thus, these data indicate that cell proliferative activity is closely correlated with biological aggressiveness and histological grading, although DNA ploidy is not useful for predicting prognosis.

Relation between cellular doxorubicin binding ability to nuclear DNA and histologic response to preoperative chemotherapy in patients with osteosarcoma

Although chemosensitivity to antiosteosarcoma agents is the most important prognostic factor in human osteosarcoma, none of the many chemosensitivity tests reported previously are reliable and clinically useful. In this study, the authors investigated the reliability and clinical availability of doxorubicin (Adriamycin; Adria Laboratories, Columbus, OH) binding assay (ABA) as a new chemosensitivity test for osteosarcoma.

Prognostic value of DNA ploidy response to chemotherapy in human osteosarcomas

We analyzed the DNA ploidy alterations after preoperative chemotherapy in 30 patients with non-metastatic osteosarcomas of the extremities. All of the patients received intensive chemotherapy with doxorubicin, cisplatin and methotrexate as well as wide tumor resection. DNA ploidy was determined by DNA cytofluorometry using isolated and smeared cells from biopsied and resected tumors after preoperative chemotherapy. The results showed that 12 diploid and nine non-diploid osteosarcomas did not change their ploidy pattern, but nine non-diploid tumors changed to a diploid pattern with the disappearance of the aneuploid cells. The nine patients with altered ploidy tumors had a better histologic response to chemotherapy and a better prognosis than the patients with non-altered tumors especially diploid tumors (P = 0.0138). Therefore, we conclude that a decrease in aneuploid cells after chemotherapy is closely correlated with a good prognosis in half of the cases of aneuploid osteosarcoma. These results also suggest that aneuploid cells are more chemosensitive than diploid cells in human osteosarcomas.

Response of DNA ploidy to chemotherapy in primary and metastatic lesions in human osteosarcomas.

Primary and pulmonary metastatic and pulmonary metastatic tumors (two synchronous and seven metachronous metastases) in nine patients with osteosarcomas were studied by DNA cytofluorometry. All patients were treated with both pre and postoperative chemotherapy. The results showed that all five diploid osteosarcomas and three of the four aneuploid tumors did not markedly change their ploidy pattern after preoperative chemotherapy, and had almost the same ploidy patterns as the pulmonary metastatic lesions. Those eight tumors showed poor histologic response and chemoresistance by the doxorubicin binding assay. Only one aneuploid osteosarcoma showing good histologic response and chemosensitivity changed its ploidy pattern to diploid, with the disappearance of aneuploid tumor cells and its synchronous pulmonary metastatic tumor also showed conversion to a diploid pattern with massive tumor necrosis. It is evident that those tumors showing no change in their ploidy pattern after chemotherapy were resistant to the chemotherapy. Therefore, we conclude that regardless of whether the pulmonary metastatic tumors were synchronous or metachronous, they showed the same change in their ploidy pattern as well as their chemosensitivity as the primary human osteosarcoma from which they were derived.