Table 2 UCCC criteria for stratification of NSCLC patients according to the EGFR FISH assay.

EGFR FISH Positive

• Specimens with EGFR gene amplification, defined as:

   (a) EGFR gene to CEP 7 ratio ≥ 2

   (b) Small gene cluster (4–10 copies) or innumerable tight gene cluster in >10% the tumor cells independent of the EGFR to CEP 7 ratio

   (c) Larger and brighter EGFR signals than CEP 7 signals in >10% the tumor cells while EGFR signals are smaller than the CEP 7 signals in the adjacent stromal and reactive cells independent of the EGFR to CEP 7 ratio

   (d) >15 copies of the EGFR signals in >10% of tumor cells independent of the EGFR to CEP 7 ratio

• Specimens with ≥ 40% of cells displaying ≥ 4 copies of the EGFR signal

EGFR FISH Negative

• Specimens without gene amplification as defined above and with <40% of cells displaying ≥ 4 copies of the EGFR signal