Tumor Shrinkage can be a Promising Diagnosis Toward Remission or can also be an Ominous Diagnosis Toward Fatality

The objective of this article is to rectify tumor shrinkage as a valid diagnosis of cancer therapy. Cancer incidence and cancer mortality keep on increasing, which are an indication that cancer has not been handled right. Perpetual proliferation of cancer cells (CCs) is the most outstanding feature of cancer. Elimination of CCs to shrink tumor became the commanding principle, which was wrong, because cancer evolved due to wound unhealing. Killing to create wound definitely is contra-indication of cancer therapy. The mistake was committed at a time when we did not have the full knowledge of cancer, which was excusable. Now we have better knowledge of cancer, but the mistake is carrying on to result in 10 million annual mortality worldwide in 2019 with an anticipated annual increment of 5%, which is not excusable. Cytotoxic therapies can only benefit a small minority of cancer patients in the early stage whose chem-surveillance have not yet fatally damaged, relying on the restoration of chemo-surveillance to subdue cancer stem cells (CSCs), which are resistant to cytotoxic agents. Under this circumstance, tumor shrinkage is a promising diagnosis toward remission. Cytotoxic therapies cause the death of a majority of cancer patients in the advanced stage whose chemo-surveillance have been fatally damaged. Under this circumstance, tumor shrinkage is an ominous diagnosis toward fatality. Tumor shrinkage should be used with discretion. Cancer is a disease created by multiple factors. The collapse of chemo-surveillance or immuno-surveillance, the evolution of cancer stem cells (CSCs) from progenitor stem cells (PSCs) due to wound unhealing, and the progression of CSCs to faster replicating CCs by the activation of oncogenes or the inactivation of suppressor genes all contribute significantly to the development of cancer. An effective cancer therapy must be able to rectify all these contributing factors. Focusing on a specific factor is insufficient. The obsession to eliminate CCs to achieve tumor shrinkage is a grave mistake of cancer establishments to result in ever-increasing cancer mortality. Actually, elimination of CSCs is more important than the elimination of CCs, because CSCs contribute most fatal effects of cancer such as metastasis, drug resistance, anti-apoptosis, angiogenesis and recurrence. Induction of terminal differentiation by cell differentiation agent (CDA) formulations is the only option to eliminate CSCs which are critically linked to wound unhealing at the primary site. Induction of terminal differentiation can also result in the elimination of CCs, which are not as tightly linked to wound unhealing as CSCs. Terminal differentiation of CSCs and CCs cannot make the tumor to disappear. Thus, CDAs violated the commanding principle of tumor shrinkage put up by the cancer establishments, and were blocked as acceptable cancer drugs. CDA formulations are obviously the only drugs that can save the lives of advanced cancer patients whose chemo-surveillance have been fatally damaged. Oncologists and advanced cancer patients must unite to push for the approval of CDA formulations to save advanced cancer patients.