Table 2. Association of pre- and post-chemotherapy mutation patterns with clinicopathological features.

Feature	Wildtype (WT)→WT Cases	Other Cases a	P value b
Total	N = 24	N = 16
Treatment Arm
A	12 (50%)	6 (38%)	0.526
B	12 (50%)	10 (63%)
Age in Years
Mean±Standard Deviation	47.5±8.7	53.0±8.8	0.059 c
Race
Chinese	17 (71%)	13 (81%)	0.711
Non-Chinese	7 (29%)	3 (19%)
Metastases
Yes	5 (21%)	5 (31%)	0.482
No	19 (79%)	11(69%)
Estrogen Receptor Status
Positive	13 (54%)	9 (56%)	1.000
Negative	11 (46%)	7 (44%)
Cycle 1 Response ≥25%
Yes	14 (58%)	10 (63%)	0.528
No	10 (42%)	6 (38%)
Overall Response Rate d
Complete Response (CR)	2 (8%)	2 (13%)
Partial Response (PR)	16 (67%)	12 (75%)	0.678 e
Stable Disease (SD)	5 (21%)	2 (13%)

^a Mutant→Mutant, Mutant→Wildtype, Wildtype→Mutant cases

^b Fisher’s exact test, two-sided P value

^c Two-sample t-test, two-sided P value

^d One WT→WT was not evaluable for overall response

^e P value from analysis of CR/PR vs SD