Sequence of Contact X-ray Brachytherapy (CXB) and External Beam Radiation (EBRT) in organ-preserving treatment for small rectal cancer.

External Beam Radiotherapy (EBRT) followed by Contact X-ray Brachytherapy (CXB) and vice versa are viable alternatives to surgery for selected rectal cancer patients who have small tumours (≤3 cm). However, the optimal sequence of treatment needs to be established. We compared two approaches using Propensity Score (PS) matching and inverse probability treatment weighting (IPTW) analyses to investigate whether the sequence of treatment affected patient outcomes. This retrospective analysis (2008-2019) included patients with rectal adenocarcinoma (cT1-3,N0-1,M0, grade 1-2, size ≤ 3 cm) who received both EBRT and CXB, irrespective of treatment sequence. PS matching and IPTW were conducted to balance covariate standardised mean differences between groups. Oncological outcomes and rate of post-treatment rectal bleeding were assessed. Following PS matching and IPTW analyses from 251 eligible patients; 103 starting with EBRT (median follow-up: 37 [IQR:18-56] months) and 148 with CXB (median follow-up: 32 [IQR:16-54] months, a significant improvement in 3-year overall survival (77% vs 85%, p = 0.02, [HR:0.58 (95% CI:0.37-0.91)]) and a higher risk of post-treatment rectal bleeding (grade 1 (26%) and grade 2 (6%)) were found in patients who started with CXB (p = 0.08). No significant differences were observed in local regrowth (18% vs 12%, p = 0.47), distant relapse (10% vs 6%, p = 0.53), 3-year organ preservation rates (70% vs 75%, p = 0.20, [HR:0.66 (95% CI: 0.35-1.26)]), or disease-free survival (78% vs 82%, p = 0.17, [HR: 0.47 (95% CI: 0.16-1.38)]) CONCLUSION: In patients with rectal cancer (≤3 cm), commencing with CXB rather than EBRT, was associated with improved overall survival, but had a higher risk of G1/2 rectal bleeding. No statistically significant differences were observed in other oncological outcomes.

Than NW ，Pritchard DM ，Hughes DM ，Duckworth CA ，Wong H ，Haq MU ，Sripadam R ，Myint AS ... -  《-》

Dose Escalation Using Contact X-ray Brachytherapy After External Beam Radiotherapy as Nonsurgical Treatment Option for Rectal Cancer: Outcomes From a Single-Center Experience.

To review the outcomes of rectal cancer patients treated with a nonsurgical approach using contact x-ray brachytherapy (CXB) when suspicious residual disease (≤3 cm) was present after external beam chemoradiation therapy/radiation therapy (EBCRT/EBRT). Outcome data for rectal cancer patients referred to our institution from 2003 to 2012 were retrieved from an institutional database. These patients were referred after initial local multidisciplinary team discussion because they were not suitable for, or had refused, surgery. All selected patients received a CXB boost after EBCRT/EBRT. Most patients received a total of 90 Gy of CXB delivered in 3 fractions over 4 weeks. The median follow-up period was 2.5 years (range 1.2-8.3). Of 345 consecutive patients with rectal cancer referred to us, 83 with suspicious residual disease (≤3 cm) after EBCRT/EBRT were identified for a CXB boost. Their median age was 72 years (range 36-87), and 58 (69.9%) were men. The initial tumor stages were cT2 (n = 28) and cT3 (n = 55), and 54.2% were node positive. A clinical complete response (cCR) was achieved in 53 patients (63.8%) after the CXB boost that followed EBCRT/EBRT. Of these 53 patients, 7 (13.2%) developed a relapse after achieving a cCR, and the 6 patients (11.6%) with nonmetastatic regrowth underwent salvage surgery (100%). At the end of the study period, 69 of 83 patients (83.1%) were cancer free. Our data suggest that a CXB boost for selected patients with suspicious residual disease (≤3 cm) after EBCRT/EBRT can be offered as an alternative to radical surgery. In our series, patients with a sustained cCR had a low rate of local regrowth, and those with nonmetastatic regrowth could be salvaged successfully. This approach could provide an alternative treatment option for elderly or comorbid patients who are not suitable for surgery and those with rectal cancer who wish to avoid surgery.

Sun Myint A ，Smith FM ，Gollins S ，Wong H ，Rao C ，Whitmarsh K ，Sripadam R ，Rooney P ，Hershman M ，Pritchard DM ... -  《-》

Organ or sphincter preservation for rectal cancer. The role of contact X-ray brachytherapy in a monocentric series of 112 patients.

Contact X-ray brachytherapy (CXB) has been used at Centre Antoine Lacassagne since 2002 to increase the chance of conservative treatment (organ or sphincter preservation) in rectal cancer. A consecutive series of 112 patients (pts) is reported. Three protocols were used in selected rectal adenocarcinomas. Group 1: T1 N0 treated with local excision (LE) followed by adjuvant CXB. Group 2: T2 or 'early' T3 N0 treated with CXB combined with chemoradiotherapy (CRT) followed by surveillance or LE. Group 3: distal 'locally advanced' T3 N0-2 treated with CXB and CRT before total proctectomy. Group 1: 27 pt (pTis: 3; pT1: 21; pT2: 3). After LE with CXB alone (20 pt) or CXB + CRT (7 pt) one local recurrence occurred. Organ preservation was achieved in 26 pt (96%). Group 2: 45 pt (T1: 2; T2: 23; T3: 20) treated with CXB alone (4 pt) or CXB + CRT or external beam radiotherapy (EBRT) (41 pt). A clinical complete response (cCR) was observed in 43/45 (96%) and 3 pt developed a local recurrence (11% at 5 years). The specific survival was 76% at 5 years and the rate of organ preservation was 89% (40/45 pt) with good bowel function in 36 pt. Group 3: 40 pt, anterior resection (with sphincter preservation) was possible in 35 pt (86%) with a 3-year local recurrence of 6%. CXB usually combined as a boost with CRT or EBRT may safely increase the chance of a conservative treatment (organ or sphincter preservation) for selected rectal cancers.

Frin AC ，Evesque L ，Gal J ，Benezery K ，François E ，Gugenheim J ，Benizri E ，Château Y ，Marcié S ，Doyen J ，Gérard JP ... -  《-》

Dose escalation using contact X-ray brachytherapy (Papillon) for rectal cancer: does it improve the chance of organ preservation?

Sun Myint A ，Smith FM ，Gollins SW ，Wong H ，Rao C ，Whitmarsh K ，Sripadam R ，Rooney P ，Hershman MJ ，Fekete Z ，Perkins K ，Pritchard DM ... -  《-》

'Folfirinox' chemotherapy combined with contact x-ray brachytherapy 50kVp and 'CAP50' chemoradiotherapy aiming at organ preservation for selected intermediate distal-middle cT2-T3 rectal cancers: A feasibility study.

The standard treatment of T2-T3 rectal adenocarcinoma is radical proctectomy by total mesorectal excision often combined with some neoadjuvant treatment. To reduce morbidity of this surgery, organ preservation strategy using various combination of radiotherapy, chemotherapy and local excision is gaining interest. Some randomized trials have proven the feasibility of such approaches. The OPERA trial demonstrated, for T2 T3<5cm diameter low-middle rectum, that a contact X-ray brachytherapy boost of 90Gy in three fractions over 4 weeks was able to achieve a planned organ preservation in 81% of patients at 3years with 97% success for tumour smaller than 3cm treated with contact X-ray brachytherapy boost first. To try to expand organ preservation to larger tumours we set up a feasibility trial in T2-T3 tumours using total neoadjuvant treatment and a contact X-ray brachytherapy boost. The trial was approved by the institutional review board of Nice. Inclusion criteria were operable patients, 75years or less, adenocarcinoma of the low-middle rectum staged T2c-T3N0 larger than 3.5cm and less than 6cm in diameter or T2-T3N1 less than 6cm in diameter. Treatment started in all cases with neoadjuvant chemotherapy associating 5-fluoro-uracile, irinotecan and oxaliplatin ('folfirinox' regimen, four to six cycles). In case of good tumour response after four cycles, a contact X-ray brachytherapy boost (delivering 90Gy in three fractions) was given followed by chemoradiotherapy (external beam radiotherapy delivering 50Gy, with concurrent capecitabine). After six cycles if only a partial response (tumour still larger than 3cm) was seen, chemoradiotherapy was given and contact X-ray brachytherapy boost was delivered after that. At the end of this total neoadjuvant treatment a watch and wait strategy was decided in case of clinical complete response or radical proctectomy by total mesorectal excision for partial response. Between July 2019 and October 2022, 14 patients were included; median age was 66years (range: 51-77years), there were nine male and five female, two T2 N1 tumours, seven T3N0, and five T3N1, all were M0. Median tumour diameter was 40mm (range: 11-50mm); three tumours had a circumferential extension greater than 50%. Seven patients received four folfirinox cycles and seven had six cycles. Contact X-ray brachytherapy boost was given during folfirinox chemotherapy before chemoradiotherapy in 11 patients (and after in three). The tolerance was good, with no grade 4-5 toxicity. The main grade 3 early toxicity was in relation with the folfirinox regimen. A clinical complete response was seen in 12 patients at the end of the total neoadjuvant treatment (85%). All these patients are alive and have preserved their rectum with a mean follow-up time of 17.8months (range: 6-48months) and a good bowel function (low anterior rectal resection syndrome score below 30). The main contact X-ray brachytherapy boost toxicity was radiation ulceration in three patients that usually healed within 6 months, sometimes necessitating hyperbaric oxygen. The preliminary results of this feasibility study show that early tolerance of these intensive total neoadjuvant treatment is compatible with an acceptable toxicity. The high rate of organ preservation in this intermediate group of T2-T3 tumours is encouraging and is a good argument to start the next randomized TRESOR trial that will aim at achieving a 65% of 3-year survival with organ preservation in this intermediate tumour group.

Mitrea D ，Barbet N ，Pacé-Loscos T ，Scouarnec C ，Ben-Dhia S ，Baron D ，Mineur L ，Évesque L ，Durand-Labrunie J ，Gérard JP ，Baudin G ，Doyen J ... -  《-》