Serum amylase and isoamylases in malignant bone tumors.

In 26 hosts of malignant bone tumors the serum amylase activities have been studied. The mean value of total serum amylase was found to be slightly elevated in the sera of patients with malignant bone tumors compared to that found in sera of blood donors. The P:S ratio of isoenzymes was found significantly (p greater than 0.01) shifted towards the S type in sera of the hosts of malignant bone tumors. The levels of the S type of isoenzymes were found to be significantly higher also in comparison to the mean values of these isoenzymes found in the sera of blood donors. Assay of the homogenate of the extirpated tissue of an osteogenic sarcoma clearly showed the amylase activity to exceed that found in patients' sera. This elevation of the total activity was found to be mainly due to the increased production of the S type of isoenzyme in the malignant tissue. The usefulness of these findings for diagnosis and prognosis purposes in bone malignancy is discussed in this paper.