The morphology of the different rat SPGs was in general good, though minor tissue shrinkage was observed in some of the SPGs.
Minor cell shrinkage was observed.
Fifty-five per cent achieved objective tumour response, and a further 27% minor tumour shrinkage; none had progressive disease.
It has been tested in a phase II study in recurrent/metastatic HNSCC but showed disease stabilisation and only minor tumour shrinkage as a single agent.
In a pilot study of treatment with Chansu extracts, 40% of advanced cancers (6/15) had prolonged disease stability or minor tumor shrinkage [ 7].
Although at least minor tumor shrinkage was observed in the majority of patients, according to RECIST criteria most patients showed stable disease on imaging and poor response (defined as > 10% vital tumor) according to the pathological specimen.
However, Miller et al (2006) showed that in their study of adenocarcinoma with bronchioloalveolar cell feature treated with erlotinib, some of the tumours with KRAS mutations showed minor tumour shrinkage, although response rate of lung cancer with KRAS mutations was zero by RECIST.
In addition, in a phase trials sponsored by our department and M.D. Anderson Cancer Center, no dose-limiting toxicity (DLT) was observed with the use of HCS at doses up to 8 times higher than typically used in China and six patients had stable disease prolonged or minor tumor shrinkage [ 29].
Other means for assessing treatment effects, such as a minor response (tumor shrinkage <30%%), disease control rates (a combination of objective response and stable disease), or the proportion of patients that are progression-free at landmark time points, could be considered as alternative metrics for providing early indications of an agent deserving additional clinical development.
Partial response was defined as a decrease of 50% or more in the product of two diameters which is maintained for at least 1 month according to WHO criteria, a minor response was 25 49% shrinkage, and progressive disease was a 25% increase.
