Nab-paclitaxel as first line treatment of gastrointestinal neuroendocrine carcinomas shows efficacious results

Dr Lorraine Chantrill - University of Sydney, Sydney, Australia

This study is a study for people with a very rare cancer and that is gastrointestinal neuroendocrine carcinoma or, in the new nomenclature, neuroendocrine neoplasm grade 3.

What was the study design?

The study was designed to test a new type of chemotherapy for these patients as traditionally we always have treated these patients with carboplatin and etoposide which is the treatment taken from the treatment of small cell lung cancer. Given that these cancers arise in the gastrointestinal tract, we thought it very reasonable to trial treatment that had, at the time, become much more common for the treatment of, for example, pancreatic adenocarcinoma.

So this study was actually designed in the early 2000s as nab-paclitaxel became a standard treatment for pancreatic cancer. So the idea was to test a combination of carboplatin and nab-paclitaxel for these gastrointestinal neuroendocrine carcinomas and compare that to the standard treatment which is carboplatin and etoposide.

What were the results of this study?

The study was actually quite challenging to recruit. We had planned to recruit about 90 patients with 45 patients in each arm, however, partway into the study we realised how difficult it was to recruit these rare cancers. So what we did, in fact, is we recruited 60 patients in total; we recruited 12 to the control arm of carboplatin and etoposide and the remainder were recruited to the active arm of carboplatin and nab-paclitaxel after an interim analysis showed that we were unlikely to recruit the 90 patients required for a 1:1 randomised trial.

So in the end what happened was we recruited those 60 patients and we were able to report the primary endpoint which, for this study, was response rate. I’m pleased to tell you that the response rate was improved with the nab-paclitaxel when compared to carboplatin and etoposide.

How do you think these results can clinically impact the treatment of this type of cancer?

Although the primary endpoint, response rate, was met and the response rate was 53% in the interventional arm compared to 42% in the control arm, there was also a trend to improvement in progression free survival and overall survival but unfortunately the study was not powered to meet those endpoints. So we would like to run a larger study, perhaps testing this combination but knowing that patients with small cell lung cancer now receive immunotherapy as standard, we think that we might try and design another trial using nab-paclitaxel in combination with carboplatin and possibly immunotherapy.

Is there anything else you would like to add?

Thank you, I’d like to end by thanking all of the study sites, the investigators, the study coordinators but, most particularly, the patients and their families who participated in this study.