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Focuses on the developments in combating bone and tissue sarcomas. Role of SSG register on bone and soft tissue sarcoma in patients; Impact of neoadjuvant chemotherapy and radiation therapy in sick persons; Details the histologic changes in the pseudocapsule of sarcomas after chemotherapy induction.

In the mid-1980s it was discovered that serotonin (5-hydroxytryptamine; 5-HT) was at least partially responsible for producing chemotherapy-induced nausea and vomiting. It was therefore realised that serotonin receptor blockade with serotonin 5-HT receptor antagonists could inhibit chemotherapy-induced nausea and vomiting. 5-HT antagonists have different chemical structures and receptor binding affinity. Granisetron, dolasetron and its major metabolite are pure 5-HT antagonists, while ondansetron and tropisetron are weak antagonists at the 5-HT receptor. Ondansetron has also been demonstrated to bind at other serotonin receptors and to the opioid µ receptor. The half-lives of granisetron, tropisetron and the active metabolite of dolasetron are 2 to 3 times longer than that of ondansetron. These observations initially suggested that more frequent ondansetron administration would be required; however, it has now been shown that receptor blockade does not correlate with elimination half-life and all 5-HT antagonists can be effectively administered once daily. Clinical trials have been conducted that directly compare the 5-HT antagonists. To compare these studies, it is necessary to assess trial design, including known risk factors for the development of chemotherapy-induced nausea and vomiting, and response criteria. Stratification for risk factors, use of strict efficacy criteria and randomisation to a blinded trial using an appropriate comparative regimen are essential for a well designed antiemetic trial. Comparative clinical trials using various doses, routes and regimens of administration have been conducted with 5-HTantagonists. Despite some trial design shortcomings, most of the studies show equal efficacy between the agents, especially in moderately emetogenic chemotherapy and mild, infrequently occurring adverse effects. The addition of steroids also appears to improve outcome. However, since many doses and regimens of ondansetron were used, further study is needed to determine the optimal regimen. The efficacy of 5-HT antagonists in controlling delayed nausea and vomiting from chemotherapy is less well studied. Further, there is no good scientific rationale for the use of 5-HTantagonists in controlling delayed nausea and vomiting since serotonin has not been shown to be released during the delayed phase. In fact, most studies show no benefit or modest benefit of 5-HT antagonists over placebo. Because the 5-HT antagonists perform similarly in the clinical setting, pharmacological differences do not seem to translate into therapeutic differences. There is also no appreciable difference in the incidence or severity of adverse effects among the 5-HT antagonists. Determination of clinical use may then be driven by cost. [ABSTRACT FROM AUTHOR]