Correlation of clinicopathological outcomes with changes in IHC4 status after NACT in locally advanced breast cancers: do pre-NACT ER/PR status act as better prognosticators?

Figures & data

Table 1 Pathological complete response (pCR) rates and its association to clinicopathological variables

Variable	Total number	Subgroup	CR		RD		P-value	Chi-square value
			Number	%	Number	%
Age group	162	<48 years (48.15%)	24	30.77	54	69.23	0.174	1.848
		≥48 years (51.85%)	17	20.24	67	79.76
Tumor stage	158	T1 and T2 (41.77%)	19	28.78	47	71.22	0.5064	0.442
		T3 and T4 (58.23%)	21	13.41	71	86.59
Nodal involvement	155	Yes (73.55%)	25	21.93	89	78.07	0.4643	0.535
		No (26.45%)	12	29.27	29	70.73
Grade	144	3 (50.69%)	20	27.4	53	72.6	0.044 (chi-square test for trend)	4.062 (chi-square value for trend)
		2 (40.97%)	12	20.34	47	79.66
		1 (8.33%)	0	0	12	100
Hormone receptor	159	Positive (75.47%)	28	23.33	92	76.67	0.6891	0.16
		Negative (24.53%)	11	28.2	28	71.8
ER	159	Positive (74.84%)	27	22.69	92	77.31	0.47	0.515
		Negative (25.16%)	12	30	28	70
PR	159	Positive (49.69%)	12	15.19	67	84.81	0.01	6.428
		Negative (50.31%)	27	33.75	53	66.25
ER/PR	159	ER and PR positive (48.43%)	11	14.28	66	85.72	0.0087 (chi-square test for trend P=0.03)	9.495 (chi-square value for trend 4.69)
		ER/PR positive (27.67%)	17	38.64	27	61.36
		ER and PR negative (23.9%)	11	28.95	27	71.05
Allred score ER	159	ER 0–2	12	30	28	70	0.003	11.89
		ER 3–5	10	52.63	9	47.37
		ER 6–8	15	16.48	76	83.51
Allred score PR	159	PR 0–2	28	35.44	51	64.56	0.005	10.46
		PR 3–5	2	11.11	16	88.89
		PR 6–8	7	13.2	46	86.8
HER2 neu	153	Positive (40.52%)	16	25.8	46	74.2	0.85	0.04
		Negative (59.48%)	21	23.07	70	76.93
Ki-67	120	Low (29.17%)	6	17.14	29	82.86	0.36	0.84
		High (70.83%)	23	27.06	62	76.94
Molecular subtype	140	Luminal A (15.7%)	3	13.64	19	86.36	0.51 (chi-square test for trend P=0.15)	2.34 (chi-square value for trend 2.03)
		Luminal B (55.7%)	19	24.36	59	75.64
		HER2 enriched (13.6%)	5	26.31	14	73.69
		Triple negative (15.7%)	7	33.33	14	66.67

Abbreviations: CR, complete response; ER, estrogen receptor; PR, progesterone receptor; RD, residual disease.

Table 2 Changes in pre- and post-NACT IHC4

IHC markers	ER positive	ER negative	PR positive	PR negative	HER2 neu positive	HER2 neu negative	Low Ki-67	High Ki-67
Pre-NACT	77.23%	22.77%	55.44%	44.56%	37.62%	62.38%	28.92%	71.08%
Post-NACT	66.34%	33.66%	57.42%	42.58%	31.68%	68.32%	50.6%	49.4%
P-value	0.0347		0.8238		0.2632		0.009
Chi-square value*					4.35	0.05	9.0312	1.25

Notes: n=101 for ER/PR/HER2 neu, n=83 for Ki-67.

* For changes in IHC4 post-NACT, McNemar’s test was performed using MedCalc version 12.

Abbreviations: ER, estrogen receptor; IHC, immunohistochemical; NACT, neoadjuvant chemotherapy; PR, progesterone receptor.

Figure 1 Kaplan–Meier estimates of relapse-free survival.

Note: (A) shows the predicted relapse-free survival (RFS) (in months, x-axis) for the three groups with differential estrogen receptor (ER) Allred scores (A=0–2, B=3–5, C=6–8); hazard ratio: Pre_chemo_ER_Allred_A 8.145, confidence interval 1.59–40.85, P<0.01; Pre_chemo_ER_Allred_B 10.243, confidence interval 1.97–57.97, P,0.01. C is the reference. (B) shows the RFS (in months, x-axis) for the three groups of progesterone (PR) Allred scores (A=0–2, B=3–5, C=6–8). There was statistically significant difference in RFS predicted for both the ER and PR groups (P=0.002 and P=0.013, respectively).

Figure 2 Kaplan–Meier estimates of relapse-free survival.

Note: Relapse-free survival (in months, x-axis) predicted for the four molecular subtypes.
Abbreviations: LA, luminal A; LB, luminal B; HE, HER2 enriched; TN, triple negative.

Figure 3 Kaplan–Meier estimates of relapse-free survival.

Note: Relapse-free survival (in months, x-axis) in groups with pathological complete response (pCR), lower Ki-67 and stable/high Ki-67 postchemotherapy.

Figure 4 Kaplan–Meier estimates of relapse-free survival.

Notes: Relapse-free survival (in months, x-axis) of tumors that changed hormone receptor from positive to negative versus from negative to positive. Log-rank P=0.06 (hazard ratio [HR] =0.2489, 95% confidence interval 0.18–1.09).