MSI in Stage II Colon Cancer: Chemotherapy or Not?

Some of the most interesting data presented at ASCO was the data on MSI and 18qLOH in a European clinical trial.

Last year at ASCO, Dr. Daniel Sargent presented new data that patients with stage II disease with microsatellite instability do not only not benefit from 5-FU, but they may be harmed, and it was recommended to test for MSI in all stage II colon cancer patients and in the presence of MSI-high not to give 5-FU. For stage III colon cancer that was not the case.

This year, the PETACC-3 clinical trial was analyzed for MSI and did not show the same the same findings. It seems that chemotherapy does not harm these patients, and they may benefit. Continue reading…

Posted by Heinz-Josef Lenz, MD on June 8th, 2009
Posted in: From the Desk of Dr. Lenz | 6 Comments »
Tags: 18qLOH, ASCO 2009, MSI, personalized medicine, Understanding Genetics

News Update: Avastin Did Not Improve Efficacy of FOLFOX in the Adjuvant Setting

A news release from last Wednesday stated that the clinical trial of NSABP C-08 was negative.

This was the clinical trial testing whether the addition of Avastin to FOLFOX would increase efficacy in reducing recurrence for patients with stage II and III colon cancer.  FOLFOX was given over 6 months compared to FOLFOX in combination with Avastin for 6 months, followed by additional 6 months of Avastin. There was a great hope that this anti-VEGF therapy would further decrease tumor recurrence. Continue reading…

Posted by Heinz-Josef Lenz, MD on April 28th, 2009
Posted in: From the Desk of Dr. Lenz | 11 Comments »
Tags: Avastin, C-08, personalized medicine, Treating Colorectal Cancer

Our Genes Determine the Success of Chemotherapy

I am not only a GI oncologist who sees patients, but I am also running a laboratory. My research tries to understand why some colon cancers respond to chemotherapy and others don’t, and why some colon cancers recur after successful removal by the surgeon.

I am trying to change the way we treat patients with colon or rectal cancer. Over the last 10 years we have identified genetic signatures which help us choose the most effective and least toxic chemotherapy. In my practice every patient with newly diagnosed colon cancer is genetically tested for KRAS and two genes which show whether FOLFOX chemotherapy is more likely to be successful. Continue reading…

Posted by Heinz-Josef Lenz, MD on January 12th, 2009
Posted in: From the Desk of Dr. Lenz | 6 Comments »
Tags: personalized medicine, Understanding Genetics

No Benefit with Erbitux in KRAS Mutated Tumors

Patients whose colorectal cancer tumors had a mutation in the KRAS gene had no benefit from treatment with Erbitux® (cetuximab).  They lived no longer after Erbitux treatment began than patients who had no Erbitux. Continue reading…

Posted by Kate Murphy on October 23rd, 2008
Posted in: Research & Treatment News | No Comments »
Tags: Erbitux, KRAS, personalized medicine

Changes in Blood Magnesium Levels Predict Response to Erbitux

Hypomagnesemia, or reduced magnesium levels, is a side effect of Erbitux® (cetuximab) treatment.  Patients with colorectal cancer whose blood magnesium dropped the fastest also had the best response to Erbitux given with Camptosar® (irinotecan) .

Italian researchers measured magnesium levels for 68 patients before treatment began and then 6 hours, 1 7, 14, 21, 50, and 92 days later.  After the seventh day, readings decreased consistently.

Magnesium levels fell at least 20 percent for 25 patients by the third week.  More of these patients responded to treatment, they lived longer before their cancer got worse and had longer overall survival. Continue reading…

Posted by Kate Murphy on July 6th, 2008
Posted in: Research & Treatment News | No Comments »
Tags: colorectal cancer prognosis, Erbitux, personalized medicine