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16 Stage II Colon Cancer: Towards an Individualized Approach
Part III
Rectal Cancer
www.ebook3000.com
175© Springer International Publishing Switzerland 2017
N. Hyman, K. Umanskiy (eds.), Difficult Decisions in Colorectal Surgery,
Difficult Decisions in Surgery: An Evidence-Based Approach,
DOI 10.1007/978-3-319-40223-9_17
Chapter 17
Rectal Cancer: Management of T1 Rectal
Cancer
Woon Kyung Jeong and Jose G. Guillem
Introduction
The widespread implementation of screening colonoscopy has led to a parallel
increase in the detection of early staged rectal cancer including T1N0M0 lesions.
Rectal cancers at this stage have invaded into the submucosal layer of the rectal wall
without metastasis to lymph nodes and other organs and have been traditionally
managed with a transabdominal radical resection (RR). However, since a RR is
associated with significant postoperative morbidity, local excisional approaches
(LE) such as transanal excision (TAE), transanal endoscopic microsurgery (TEM),
and transanal minimally invasive surgery (TAMIS), have been adopted. Whether
the oncological results of a less morbid LE approach is comparable to a more mor-
bid RR approach for T1N0M0 rectal cancer is the essential question of this
chapter.
When confronted with a patient with a presumed T1N0M0 rectal cancer based
on preoperative physical exam and imaging studies, both LE and RR options have
to be considered and the pros and cons of each approach and their associated long-
term and short-term oncological outcomes and functional consequences and impli-
cations for the specific patient at hand carefully discussed.
W.K. Jeong • J.G. Guillem (*)
Colorectal Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center,
New York, NY, USA
e-mail: guillemj@MSKCC.ORG
176
Search Strategy
P (patients) I (intervention) C (comparator) O (outcomes)
Patients with T1 rectal
cancer
Local excision Radical resection Oncologic outcomes,
quality of life
A literature search in Pubmed, Embase, and Scopus databases was performed. The
terms used for the search included: “T1 rectal cancer”; “early staged rectal cancer”;
“local excision”; “radical resection”; “recurrence”; “sexual function”; “anorectal
function” and “quality of life”. Only articles written in English and published
between 2010 and 2015 and reporting original data or meta-analysis on T1 rectal
cancer were selected. Important and evidence-based studies published before 2010
were also included.
Results
We found two meta-analyses which met our search criteria and included most of the
significant data on the topic (Table 17.1) [1, 2]. Of these two studies, one was larger
(2896 patients from 13 studies [1] versus 860 patients from seven studies [2]) and
reported detailed preoperative diagnostic workup and oncologic data including lym-
phovascular invasion and surgical margin status as well as the use of neoadjuvant
and/or adjuvant therapy [1]. However, these two meta-analyses included studies that
were retrospective and non-randomized [3–15], and some of the retrospective stud-
ies included small numbers of patients. The one prospective randomized study on
this topic which was included in both meta-analyses only enrolled 50 patients [16].
Oncologic Outcomes
Local Recurrence
In our review of these two meta-analyses, rates of local recurrence were higher in
patients undergoing a LE when compared to patients undergoing a RR (4–33 %
versus 0–6 %, respectively) [1, 2].
Distant Metastasis
Of these two meta-analyses, only one compared distant metastasis rates between LE
and RR and showed no significant differences (0–8 % versus 0–4 %, respectively)
[2]. However, it is important to point out that this study included only patients
undergoing TEM and did not include TAE or TAMIS.
W.K. Jeong and J.G. Guillem
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177
Table 17.1 Comparison of meta-analysis studies on T1 rectal cancer
Study Year
Study
design
Patients
(LE/RR)
Local
recurrence
Distant
metastasis DFS OS Morbidity Mortality
Quality of
evidence
Kidane
et al. [1]
(TAE,
TEM,
TAMIS
vs. RR)
2015 Meta-
analysis
2896
(1315/1581)
LE > RR
(relative risk,
2.36; 95 %
CI,
1.64–3.39)
n/a 5-years DFS,
LE < RR
(relative risk,
1.54; 95 % CI,
1.15–2.05)
5-years OS,
LE < RR
(relative risk,
1.46; 95 % CI,
1.19–1.77)
LE < RR
(relative
risk, 0.20;
95 % CI,
0.10–0.41)
LE < RR
(relative
risk,
0.31;
95 % CI,
0.14–
0.71)
moderate
Lu et al.
[2] (TEM
vs. RR)
2015 Meta-
analysis
860
(303/557)
LE > RR(OR,
4.62; 95 %
CI,
2.03–10.53)
no difference
(OR, 0.74;
95 % CI,
0.32–1.72)
no
difference(OR,
1.12; 95 % CI,
0.31–4.12)
no
difference(OR,
0.87; 95 % CI,
0.55–1.38)
n/a n/a moderate
LE local excision, RR radical resection, DFS disease-free survival, OS, overall survival, TAE, transanal excision, TEM, transanal endoscopic microsurgery,
TAMIS, transanal minimally invasive surgery, CI, confidence interval, OR, overall risk, SEER, surveillance, epidemiology, and end results, HR hazard risk
17 Rectal Cancer: Management of T1 Rectal Cancer
178
Overall Outcome
In one meta-analysis, disease-free survival rate was higher in patients undergoing a
RR [1]. However, in the other meta-analysis, no significant difference was noted in
disease-free survival between the two surgical treatment options [2]. This may be
due to the fact that in the latter met-analysis, only 2 studies reporting disease-free
survival were included.
With regard to overall survival, one meta-analysis showed better results for RR
over LE [1]. The other meta-analysis did not, even though it did demonstrate a sig-
nificantly higher local recurrence rate in patients undergoing a LE (odds ratio, 4.62;
95 % confidence interval, 2.03–10.53) [2]. The authors do not provide an explana-
tion for this. However, it is possible that salvage radical surgery and adjuvant che-
motherapy and/or radiation therapy may have eradicated some of the locally
recurrent rectal cancer and impacted survival in a positive manner. However, other
studies suggest that failure following a local excision may not be salvageable in a
significant number of cases [17].
Quality of Life
Of the two meta-analyses, only one reported on morbidity and noted a higher mor-
bidity rate for RR over LE [1]. LE was associated with a much lower need for per-
manent stoma [1]. However, a number of the studies included were from over 20
years ago when sphincter sparing TME was not as established as it is today.
There is a paucity of literature comparing sexual or anorectal functions following
RR and LE and none are prospective randomized studies. Therefore, the two meta-
analyses [1, 2] did not discuss this topic. One study not included in the two meta-
analysis, however, did compare the quality of life after TEM and TME in sex- and
age-matched patients and reported no significant differences in quality of life between
TEM and TME; but more frequent defecation disorders were observed after TME
[18]. A trend toward better sexual function after TEM was also reported. However, a
greater portion of patients in the TME group were T3 and received preoperative radio-
therapy (18 % versus 0 %) which probably had a negative impact on sexual function.
Other Studies
There are several recently published papers comparing local excision to radical
resection that were not included in our analyses for specific reasons. One study
included T1 and T2 rectal cancers and did not provide a subset analysis on T1 cancers
[19] and the other included endoscopic polypectomy in the LE group [20]. One sin-
gle institution study comparing LE to RR was not included in either of the meta-
analyses [21]. It was a small sample (n = 124), retrospective study which demonstrated
W.K. Jeong and J.G. Guillem
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179
a local recurrence rate of 11 % in the LE group versus 1.6 % in the RR group, but no
difference in the disease-free and overall survival between the two groups. Our insti-
tutional experience at Memorial Sloan-Kettering Cancer Center (MSKCC) on a
larger cohort (n = 282) with a similar length of follow-up demonstrated an inferior
disease-specific survival for patients with a T1 rectal cancer undergoing a LE relative
to those undergoing a RR (87 % versus 96 %) [12].
In summary, the best available data suggest that a RR offers an oncologic advan-
tage over a LE approach for early staged (T1N0M0) rectal cancer. This is probably
related to the increased likelihood of a local recurrence noted after a LE approach,
which is not always salvageable.
Evidence Based Recommendations
A review of the published oncological results demonstrates that a RR provides the
best oncologic outcome for a T1 rectal cancer. LE is an option for patients with T1
rectal cancer without high risk features who either are not suitable for a RR or are
willing to accept the oncological risks in the interest of avoiding the functional
consequences of a RR. There should not be enlarged mesorectal lymph nodes suspi-
cious for metastasis on preoperative images nor evidence of poor differentiation
(PD), lymphovascular invasion (LVI), perineural invasion (PNI), or submucosal
(Sm) invasion >1 mm on pathological analysis. If one of these high risk features in
noted, a RR is recommended [22, 23]. If such a patient were to insist on having a LE
rather than the recommended RR, they have to understand that local recurrence
rates after LE of a T1 rectal cancer range between 12 and 29 % with long-term fol-
low-up, despite applying careful selection criteria for LE [5, 10, 15, 24, 25]. If a
local recurrence develops and a salvage surgery is pursued, it would likely be exten-
sive as one study reported the need for multivisceral pelvic resection in 33 % and
total pelvic exenteration in 5 % of patients undergoing a RR after a recurrence fol-
lowing a LE of T1 rectal cancer [17].
1. Patients with a T1N0M0 rectal cancer that are otherwise fit should be offered a
radical resection incorporating mesorectal excision.
2. Patients with a T1N0M0 rectal cancer not able to undergo a radical resection
may be offered a local excision understanding the increased risk for failure with
possible limited salvage options.
Grade of data: moderate quality
A Personal View/Approach
If a patient is found to have a biopsy proven rectal adenocarcinoma that clinically
looks and feels like it is not deeply invasive (mobile, non tethered, exophytic rather
17 Rectal Cancer: Management of T1 Rectal Cancer
180
than ulcerated) and possibly amenable to a LE, a careful review of the pathology as
well as local [endorectal ultrasonography (ERUS) or rectal magnetic resonance
imaging (MRI)] and distant [computed tomography (CT) of chest, abdomen and
pelvis] staging has to occur in order to further determine if indeed a LE approach is
appropriate. The presence of any adverse pathological features (PD, LVI, PNI, or
Sm invasion >1 mm) would be associated with an increased likelihood of mesorec-
tal lymph node involvement and in an otherwise healthy individual with good ano-
rectal sphincter function (good baseline tonicity, squeeze, no paradoxical motion of
puborectalis sling, etc.), a RR would be offered. In an elderly individual with signifi-
cant co-morbidities and/or poor anorectal function, a LE approach would be a safer
initial approach (lower morbidity, mortality, and probable better function) than a RR
but would be associated with a possible increased risk of local and distant failure. A
more challenging scenario is the otherwise healthy individual with a very distal
(1 cm above upper part of anorectal sphincter) invasive (T1N0M0 on imaging) rec-
tal adenocarcinoma with good pathological features who is interested in a restor-
ative curative resection. In this situation, the patient has to be informed that if LE is
pursued initially and pathology identifies a T2 lesion and he/she were to pursue a
subsequent salvage RR, this may or may not be feasible since the prior suture line
fibrosis of LE would compromise creation of coloanal anastomosis and function.
Numerous other clinical scenarios exist based upon the local and distant staging
of the rectal cancer, the presence or absence of poor pathological features, the distal-
most location of the lesion relative to the upper most portion of the anorectal sphinc-
ters, the function of the anorectal sphincters, the presence or absence of
co-morbidities, etc. Optimal matching of the treatment plan to the individual patient
requires that all the above variables be taken into consideration and that the patient
and family be informed and engaged in a discussion where short and long term
wishes, risks, gains and losses are clearly discussed and agreed upon.
References
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treatment of T1N0M0 rectal adenocarcinoma: a systematic review and meta-analysis. Dis
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17 Rectal Cancer: Management of T1 Rectal Cancer