Cathy Eng, MD, FACP: Second EGFR-Directed Therapy and Mutational Status

Would you consider another EGFR-directed therapy in this patient, and does her mutational status affect your decision?

CASE: Metastatic Colorectal Cancer (Part 2)

Following her first-line recurrence, Diane is switched to FOLFIRI, and bevacizumab is continued.

• After 3 cycles, her CEA decreased to 19 ng/mL. The patient remained asymptomatic, and her hepatic lesions were stable

In July of 2014, she presents to her oncologist with fatigue, dyspnea, and worsening performance status, and her CEA had increased to 180 ng/mL.

• CT scan revealed progression of multiple hepatic lesions, with several new nodules noted in the lung right upper lobe
• Biopsy of the lung and liver lesions was consistent with metastatic disease, and both samples were sent for mutational analysis

Based on results of her mutational analysis, which showed KRAS WT; BRAF negative; RAS WT, the patient is considered eligible for treatment with an anti-EGFR agent, and she is initiated on cetuximab + irinotecan.

• Cetuximab infusion was delayed after the first cycle for 1 week due to rash
• After 4 cycles, she shows a response with her CEA decreasing to 32 ng/mL, and a reduction in hepatic lesions and stable lung lesions on CT.

In November of 2014, the patient presents with dyspnea, increasing CEA and worsening performance status.

• Her CT scan is consistent with progression of lung lesions