Clinicopathologic Comparison of High-Dose-Rate Endorectal Brachytherapy versus Conventional Chemoradiotherapy in the Neoadjuvant Setting for Resectable Stages II and III Low Rectal Cancer

Table 3

Radiologic outcomes broken down by EBT, 3DRT, and IMRT groups with statistical comparison. EBT: endorectal brachytherapy; 3DRT: 3D conformal radiotherapy; IMRT: intensity-modulated radiotherapy; RT: radiotherapy; CR: complete response; PR: partial response; SD: stable disease; PD: progressive disease; LN: lymph nodes.

Radiologic outcome	EBT (𝑛=7)	3DRT (𝑛=10)	IMRT (𝑛=7)	𝑃
Post-RT tumor volume (median (range) cm^3)	1.0 (0.0–3.6)	3.8 (0.7–26.3)	0.4 (0.0–5.5)	0.16^*
Time between RT end and post-RT MRI (mean ± SD days)	35±3	35±7	36±9	0.98
% decrease in tumor volume pre-RT → post-RT (median (range))	89 (38–100)	87 (16–96)	93 (66–100)	0.78
No. CR (%)	1 (14)	0 (0)	1 (14)	0.46
No. PR (%)	4 (57)	9 (90)	6 (86)	0.23
No. SD (%)	2 (29)	1 (10)	0 (0)	0.26
No. PD (%)	0 (0)	0 (0)	0 (0)	1.0
No. with clinically significant mesorectal LN before treatment (%) → no. after treatment (%)	1(14)→0(0)	6(43)→3(21)	1(14)→1(14)	—
No. with clinically significant pelvic LN before treatment (%) → no. after treatment (%)	0(0)→0(0)	4(29)→4(29)	1(14)→0(0)	—

^*Medians and ranges are given to better represent the data, but statistical comparison was performed among means.