Clinical outcome of interstitial pulsed dose rate brachytherapy in multimodality treatment of locally advanced primary or recurrent rectal and sigmoid cancer with high risk of incomplete microscopic resection

Figures & data

Table 1. Patient characteristics of 73 patients with locally advanced primary or recurrent rectal and sigmoid cancer with high risk of R1 resection treated with pulsed dose rate brachytherapy.

	All	Primary	Recurrent
No. of patients	73	30	43
Rectal cancer	67	29	38
Sigmoid cancer	6	1	5
Gender
Male	53	21	32
Female	20	9	11
Age (median, range)	62 (38–82)	63 (38–82)	62 (39–74)
Prior surgery
Hartmann	7	0	7
Rectum resection	21	0	21
Rectum extirpation^a	12	0	12
Sigmoid resection	3	0	3
Prior radiotherapy	20	3^b	17

^a Including proctocolectomy in one patient because of synchronic colon cancer.

^b Due to other cancer.

Table 2. Treatment characteristics for 73 patients with locally advanced primary or recurrent rectal and sigmoid cancer with high risk of R1 resection treated with external beam radiotherapy, extensive surgery and pulsed dose rate brachytherapy.

Disease status	All	Primary	Recurrent
Radiotherapy
Preoperative EBRT^a	53	26	27
Postoperative EBRT	16	3	13
No EBRT	4	1	3
Surgery
Total pelvic exenteration	35	11	24
Resection of os coccyges	18	5	13
Resection of os sacrum	18	6	12
Resection status
Complete resection (R0)	23	10	13
Microscopic incomplete (R1)	45	19	26
Macroscopic incomplete (R2)	5	1	4
Brachytherapy
3 catheters	26	13	13
4 catheters	22	7	15
5 catheters	13	8	5
6 catheters	6	3	3
7–8 catheters	6	2	4
D90 (mean; range)^b	36 (24–45)	35 (24–41)	36 (28–45)

^a External beam radiotherapy.

^b Data from 17 patients using Theraplan were not available.

Figure 1. Postoperative interstitial pulsed dose rate brachytherapy (PDR-BT) in a patient with locally recurrent rectal cancer with high risk of R1 resection. (a) Catheters for brachytherapy sutured to the tumour bed. The catheters were later covered by a pediculated myocutaneous flap (rectus abdominis) preventing direct contact between the intestines and the high dose volume. (b) Treatment plan delivering 30 Gy (cyan contour) given with 0.6 Gy per pulse, one pulse per hour to the BT target (red contour). Dose planning was conducted with manual dose optimisation avoiding overlap of double dose volumes i.e., 60 Gy (yellow contour).

Figure 2. Clinical outcome in 73 patients with locally advanced primary or recurrent rectal and sigmoid cancer with high risk of R1 resection treated with pulsed dose rate brachytherapy (PDR-BT). (a) Local control (LC) and overall survival (OS) of the entire group. (b) Local control related to the number of catheters used for brachytherapy. (c) Local control in relation to resection margin (R-stage). (d) Freedom from Grade 3, 4 and 5 overall and specific brachytherapy-related morbidity (Table 3).

Table 3. Early (within 90 days) and late complications (>90 days) retrospectively scored according to CTCv3.0 in 73 patients with locally advanced primary or recurrent rectal and sigmoid cancer with high risk of R1 resection treated with external beam radiotherapy, extensive surgery and pulsed dose rate brachytherapy.

Early complications	Grade 1	Grade 2	Grade 3	Grade 4	Grade 5
Sepsis			4
Urinary infection		4	3	2
Pneumonia	1	2	4		1
Soft tissue infection	1	1	1
Infection in pelvis		1	4
Infection in bone			1
Ileus	1		1
Anastomosis leakage	1	1	3
Fistula			4	2
Stoma problems		1	2
Bladder emptying problems	1	1	2
Thrombosis		1
Soft tissue necrosis^a		1	1
Neuropathy^a	2	2
Neural pain^a	1	3
Late complications	Grade 1	Grade 2	Grade 3	Grade 4
Urinary infection		4	1	1
Infection in pelvis			1
Infection in bone			1
Ileus		1	1
Anastomosis leakage	1			1
Fistula		1	6
Stoma problems	2	3
Bladder emptying problems	5	7	4	1
Kidney failure			1
Thrombosis		2
Soft tissue necrosis^a		1	1	1
Osteo necrosis^a				1
Insufficiency fracture^a	1
Neuropathy^a	2	2
Neural pain^a	2	9

^a Considered to be specific to brachytherapy.