Organ preservation in rectal adenocarcinoma (T1) T2-T3 Nx M0. Historical overview of the Lyon Sud - nice experience using contact x-ray brachytherapy and external beam radiotherapy for 120 patients.

In most institutions, standard treatment of T2-T3 rectal adenocarcinoma is radical surgery using total mesorectal excision (TME) with or without neoadjuvant treatment [radiotherapy or chemoradiotherapy (CRT)]. Abdomino-perineal excision (APE) is considered by most patients as a severe mutilation but even with low anterior resection (LAR) morbidity is not negligible [1]. Further, postoperative mortality, especially in elderly patients is of great concern [2]. To improve quality of life and individualize treatment, an increasing number of experienced colorectal surgeons are advocating organ preservation using CRT followed either by local excision (LE) [3,4] or only close surveillance after clinical complete response (cCR) usually in T2 or ‘ early T3 ’ tumors [5,6]. In Sao Paulo, Habr-Gama has since many years been the pioneer of such an approach recommending careful evaluation of the clinical tumor response [7] using a long interval after the end of CRT. In case of cCR, her strategy is to adopt a ‘ watch and wait ’ (W-W) policy [8]. In Lyon, Papillon using contact x-ray brachytherapy (CXB) alone was able in the 1970s to achieve close to 90% cCR in more than 300 T1 N0 lesions and gave his name to this technique [9]. Since the mid-1980s, CXB was combined with external beam radiation therapy (EBRT) in order to treat, mainly in inoperable patients, T2-3 tumors at higher risk of perirectal nodal extension [10,11]. Similar approaches were used in various French, British and American institutions [12 – 15]. Since the mid-1990s, CXB was progressively abandoned for four reasons: the Philips RT 50 TM Contact machine was not manufactured anymore, technological innovations drove the interest of radiation oncologists towards three-dimensional (3D) image-guided radiotherapy, they progressively lost the clinical expertise of rigid rectoscopy and LE became the primary treatment of malignant polyps or T1N0 tumors. In 2009 a new Contact machine named Papillon 50 TM , producing a similar 50 kV x-ray beam was introduced in UK and France and initiated a renaissance of this technique [16]. We report here an overview of the use of CXB during a time period of 35 years by a homogeneous team of radiation oncologists working successively in CHU Lyon Sud and Centre Antoine Lacassagne in Nice. The report will focus exclusively on the combined treatment using CXB with EBRT to achieve organ preservation in T2 to early T3 rectal adenocarcinomas.