An 80-year-old man presenting hematochezia was referred to our institution due to
a 20 mm slightly elevated rectal lesion with a central depression (Paris 0–IIa+c)
on the right-posterior rectal wall below the inferior Houstonʼs valve ([Video 1]). The macroscopic appearance and virtual chromoendoscopy (JNET III surface and vascular
pattern) suggested a deeply invasive cancer ([Fig. 1]). Staging pelvic magnetic resonance imaging revealed rectal cancer with invasion
but partial preservation of the muscularis propria (T1b/early T2) without malignant
lymph nodes or extramural vascular invasion. A total body computer tomography (CT)
scan did not reveal distant metastases. After a multidisciplinary team discussion,
the patient refused total mesorectal excision, and an endoscopic local excision was
then offered.
Focal endoscopic intermuscular dissection achieving a radical resection of an early
T2 rectal cancer.Video 1
Fig. 1 White light appearance (left) of a Paris 0–IIa+c lesion, 20 mm in diameter, located
on the right-posterior wall of the distal rectum. Virtual chromoendoscopy (right)
was suggestive of deeply invasive cancer (amorphous surface and loose vessel areas,
Japan NBI Expert Team [JNET] classification III).
Creating a submucosal pocket towards the deeply invasive component (pocket-detection
method
[1]
[2]), the muscle-retracting sign indicating the deeply invasive area within the lesion
was
identified ([Fig. 2]) and circumferentially isolated [3]. Following multiband-and-wire pulley traction [4] application, incision of the circular layer of the muscularis propria was performed
around the suspected invasive component at a safety distance of 3 mm to achieve R0
while
minimising the intermuscular dissection area ([Fig. 3]). The focal endoscopic intermuscular dissection (EID) was completed without
complications, and the patient was discharged 24 hours after the resection. Histopathology
([Fig. 4]) revealed a radical resection of a well-differentiated adenocarcinoma invading the
muscularis propria without lymphovascular invasion or tumour budding (pT2). Given
the radical
resection and the patientʼs age and preference, the multidisciplinary team agreed
on a
follow-up. At the 3-month follow-up, there was no endoscopic recurrence or functional
impairment, and the total body CT scan revealed no distant metastases.
Fig. 2 Muscle-retracting sign. Submucosal invasion and fibrosis causing tethering of the
muscularis propria to the overlying lesion, narrowing of the submucosal space, and
non-staining submucosa. Appearance under saline immersion (left) and CO2 insufflation (right).
Fig. 3 Appearance of the resection defect following the circumferential incision of the circular
layer of the muscularis propria. The submucosal and intermuscular dissection planes
are exposed by the multiband-and-wire pulley traction.
Fig. 4 Tissue section (hematoxylin and eosin staining) of the rectal endoscopic resection
specimen showing a low-grade adenocarcinoma invading deep into the muscularis propria
with margins free of neoplasia. M = mucosa, SM = submucosa, MP = muscularis propria.
The dashed line marks the invasive front of the tumour.
The novel focal EID guided by the pocket-detection method enabled safe and R0 resection
of a T2 rectal cancer in an elderly patient refusing surgery. Focal EID may decrease
the area of circular muscular resection, potentially reducing procedural time and
complication rates.
Endoscopy_UCTN_Code_TTT_1AQ_2AD_3AZ
E-Videos is an open access online section of the journal Endoscopy, reporting on interesting cases and new techniques in gastroenterological endoscopy.
All papers include a high-quality video and are published with a Creative Commons
CC-BY license. Endoscopy E-Videos qualify for HINARI discounts and waivers and eligibility is automatically checked during the submission
process. We grant 100% waivers to articles whose corresponding authors are based in
Group A countries and 50% waivers to those who are based in Group B countries as classified
by Research4Life (see: https://www.research4life.org/access/eligibility/).
This section has its own submission website at https://mc.manuscriptcentral.com/e-videos.
