Sometimes, not always, when a primary NET (neuroendocrine tumor) is removed and metastastatic tumors are already present, their growth is accelerated. However, sometimes the opposite occurs and their growth is related. These effects are thought to result from growth stimulating factor shifting to the metastases after their primary target is removed. On the other hand self-stimulating factors produced by the primary tumor also stimulate growth of metastases and these areas reduced by removing the primary tumor. It is a complicated situation which might be best handled by treating the tumor with tumor inhibiting medicines before and after surgery such as Sandostatin, alpha-interferon, chemotherapy, etc.
