Higher Volume at Time of Breast Conserving Surgery Reduces Re-Excision in DCIS

Table 5

(a) The rate of re-excision for each surgeon compared to type of surgery (BCS/BCS-AM).

Surgeon*	BCS			BCS-AM
	# Re-exc	Total	Percent	# Re-exc	Total	Percent
A	24	35	68.57%	17	31	54.84%
B	18	37	48.65%	11	39	28.21%
C	41	78	52.56%	9	20	45.00%
D	20	22	90.91%	12	43	27.91%
Summary	chi squared		P value	chi squared		P Value
Total	5.455184		0.141355**	4.807951		0.186487**

*Only top four surgeons were chose to keep power of the test above 0.80.

(b) The rate of re-excision for each surgeon compared by average total volume of excision (cm³).

Surgeon*	A	B	C	D
Volume	80.94	97.06	102.88	57.40
St Dev	72.45	86.98	124.09	51.14
N	41	29	50	32
F statistic.		1.77	P value	0.156

*Only top four surgeons were chose to keep power of the test above 0.80.

(c) The rate of re-excision for each surgeon compared relative to margin size.

Margin size	Surgeon A		Surgeon B		Surgeon C		Surgeon D		Total
	Re-exc	n	Re-exc	n	Re-exc	n	Re-exc	n	Re-exc	n	P value
Pos	25	32	25	35	42	48	29	33	121	148	.836699
1-2 mm	9	10	3	7	2	5	2	5	16	27	.468393
3–5 mm	6	9	0	7	2	8	1	2	9	26	.141999
6–9 mm	0	5	1	4	0	1	0	0	1	10	.472367
Neg	1	10	0	23	4	34	0	24	5	91	.145699
Total	40	56	29	53	46	62	32	40	147	211