Rapid Assessment of the Efficacy of Neoadjuvant Therapy for Soft Tissue Sarcomas

I have posted  previous notes about the use of laboratory tests and medical imaging to monitor the therapeutic effectiveness of therapy, particularly chemotherapy, for cancer (see: Moving Resources from the Therapeutic to the Diagnostic Silo, Biomarkers Used to Assess Treatment Efficacy, A Look at Deloitte's Healthcare Reform Pyramid: A Strategy for Reducing Costs. Modification of therapy shown to be ineffective avoids both unnecessary costs and the potential complications of that therapy. Below is an excerpt from an article that discusses how PET combined with CT can be used in this way (see: Using PET/CT imaging, UCLA researchers can tell after a single treatment if chemotherapy is working):

Oncologists often have to wait months before they can determine whether a treatment is working. Now, using a non-invasive method, researchers at UCLA's Jonsson Comprehensive Cancer Center have shown that they can determine after a single cycle of chemotherapy whether the toxic drugs are killing the cancer or not. Using a combination Positron Emission Tomography (PET) and computed tomography (CT) scanner, researchers monitored 50 patients undergoing treatment for high-grade soft tissue sarcomas. The patients were receiving neoadjuvant chemotherapy treatments to shrink their tumors prior to surgery. The study found that response could be determined about a week after the first dose of chemotherapy drugs. Typically, patients are scanned at about three months into chemotherapy to determine whether the treatment is working....PET scanning shows biochemical functions in real time, acting as a sort of molecular camera. For this study, [the research team] monitored the tumor's metabolic function, or how much sugar was being consumed by the cancer cells....In order to identify an effective response to treatment, researchers needed to see a 35 percent decrease in the tumor's metabolic activity. Of the 50 patients in the study, 28 did not respond and [the treating physicians] knew within a week of their initial treatment. This allows the treatment course to be discontinued or changed to another more effective treatment, getting the patient to surgery more quickly. Although this study was performed in patients scheduled for surgery, [the researchers opined that the] findings will have an even greater impact on patients with inoperable tumors or metastatic disease as you get a much quicker evaluation of treatment effectiveness and can make decisions that will hugely impact quality of life.

Neoadjuvant therapy is any initial treatment for cancer such as chemotherapy that shrinks a tumor prior to surgery. Soft tissue sarcomas are notoriously difficult to treat with chemotherapy and neoadjuvant therapy is uncommon for these patients. Hence, rapid assessment of the value of the neoadjuvant therapy, when used in such a setting, is desirable. As emphasized above, however, the use of PET plus CT will have an even greater effect on the treatment of patients with inoperable tumors and metastatic disease. Although this article does not address the topic of clinical trials for various chemotherapy regimens, rapid assessment of therapeutic effectiveness using PET and CT may alter the way such research is conducted. For example, it may be possible to terminate trials early if the new drug combinations being tested show no obvious advantage over standard therapy.

Comments

[bariatric surgery]

So this is a type of treatment for the initial stage for a person suffering from cancer.Even when chemotherapy is used before surgery or radiation, it is known as primary chemotherapy or neoadjuvant chemotherapy. Because the cancer cells have not yet been exposed to anti-cancer drugs, they are especially vulnerable.