Genentech's Trastuzumab Emtansine (T-DM1) Reduces The Risk Of Cancer Worsening

gdpawel · 06-06-2012, 09:51 AM

"Another synergy to be better explored is combining treatment modalities."

Very good point Rich!

I've always been an advocate of surgery then chemo or radiation, depending on the tumor type. For example: NSCLC is not intrinsically sensitive to chemo, where radiation if more of a factor. SCLC is intrinsically sensitive to chemo. BRCA cancers are hypersensitive to chemo.

MJ

Progression-free survival (PFS) is the length of time during and after treatment in which a patient is living with a disease that does not get worse.

Time to progression (TTP) is a measure of time after a disease is diagnosed (or treated) until the disease starts to get worse.

In the Annals of Oncology, it states that clinical investigators seem to be frequently using PFS and TTP interchangeably in cancer. Such use of terms may lead to confusion when results of different trials are compared.

The survival gain induced by chemotherapy is considered to be the time the tumor requires to return to a size similar to what existed before chemotherapy. In calculating survival gained by tumor shrinkage, it is approximately 2 months in 50% reduction, 3 and a half months in 75% reduction and 1 year in 99% reduction. The data indicate that in cases evaluated with reduction rates more than 90%, there may be a significant correlation between response rate and survival.

Clinical trials virtually always have time to disease progression as a primary endpoint. Without imaging studies, one can't get accurate time to progression data. So tests are performed for the benefit of drug companies seeking new drug approval, for clinical investigators seeking contracts and publications, and for clinicians seeking an easy way to make clinical decisions.

The final arbiter of clinical approval is overall survival. Progression-free survival does not address the patient's quality of life during what little additional months of some serious side effects that can be experienced. And drug response is not even a reliable predictor of overall survival. Overall survival is based on death from any cause like side effects of treatment and effects on survival after relapse.

Greg