Keywords
Cancer - rectal - reporting - structured - template
Introduction
The role of MRI is well established in the assessment and local staging of rectal
cancer, selection of the appropriate treatment strategy, and patient prognostication.[1] MRI features such as involvement of the circumferential resection margin (CRM),
T staging, and nodal status help decide whether the patient requires pre-operative
neo adjuvant chemo radiation or upfront surgery.[1], [2], [3] Presence or absence of sphincter complex involvement, intersphincteric space involvement
and extramural venous invasion (EMVI), amongst other findings, helps in deciding the
appropriate surgery and in prognosticating the patient.[1], [3]
Given the important role that the radiologist has to play in rectal cancer management,
it is essential for an MRI report to contain all the relevant details, which will
help in guiding appropriate patient management. The use of structured reporting in
radiology has been reported to ensure that clinically important findings are more
often integrated in the report.[2] Structured reporting is especially useful in certain examinations where detailed
and specific information is needed to be mentioned in the MRI report in order to make
treatment decisions.[4] Rectal cancer MRI is one such examination which is reported to benefit from such
reporting.[2]
Many societies, including the Society of Abdominal Radiology rectal cancer disease-focused
panel,[4] the European Society of Gastrointestinal and Abdominal Radiology[5] and the Korean Society of Abdominal Radiology[6] have provided recommendations and templates to be used for reporting baseline and
post-treatment rectal MRIs. These recommendations have been made in order to ensure
strict quality control in the MRI reports being generated. The proposed templates
consist of a list of essential imaging features to be mentioned in every report with
the objective of ensuring a practically easy to implement list which is simple and
straightforward for the clinicians and surgeons to understand.
We created and implemented a similar structured template for use in rectal cancer
reporting in our department in 2017. We studied the impact of using this template
at our hospital for the evaluation of rectal cancer in terms of number of essential
imaging parameters described in the reports as compared to the pre-template free-text
reports.
Methods
Being a tertiary care cancer center, all radiologists in our department work in conjunction
with various multidisciplinary tumor boards or disease management groups. A structured
rectal MRI reporting template was introduced in the department in August 2017 for
standardization of rectal MRI reporting. The template was created in consensus with
members of the colorectal tumor board, which consists of colorectal surgeons, dedicated
gastrointestinal (GI) radiation and medical oncologists, along with subspecialty radiologists
and pathologists.
A dedicated talk was conducted for the radiology residents and faculty, following
which the template was adopted across the board. The template included 14 essential
parameters like T2 signal intensity of the tumor, presence of restricted diffusion,
extramural vascular invasion etc., to be mentioned in rectal MRI reports [Table 1] and [Figures 1], [2], [3], [4], [5], [6]. All baseline as well as post-treatment rectal MRIs were reported using the template
by ‘general’ (non-GI) onco-radiologists as well as dedicated GI sub-specialty radiologists.
Table 1
MRI parameters covered in the reports before and after implementation of the structured
template
|
Essential reporting parameters
|
Reported in percentage of cases (%)
|
P
|
|
Free text reports
|
Template reports
|
|
Median, range and IQR of number of essential imaging parameters reported in free text
and template reports
|
|
Location of tumor
|
100
|
94
|
|
|
Length of tumor
|
86
|
100
|
0.4
|
|
Distance from anal verge
|
92
|
100
|
0.6
|
|
Tumoral T2 signal intensity
|
68
|
92
|
0.1
|
|
Restricted diffusion
|
22
|
100
|
<0.0001
|
|
Depth of extra-serosal extension/Distance from mesorectal fascia
|
48
|
98
|
0.002
|
|
Circumferential resection margin status
|
90
|
100
|
0.6
|
|
Anterior peritoneal reflection involvement
|
30
|
100
|
<0.0001
|
|
Organ involvement
|
86
|
100
|
0.4
|
|
Anal sphincter involvement
|
84
|
98
|
0.4
|
|
T stage
|
16
|
98
|
<0.0001
|
|
Extra mural vascular invasion
|
50
|
100
|
0.003
|
|
Mesorectal nodes
|
96
|
100
|
0.8
|
|
Extra mesorectal nodes
|
96
|
98
|
0.9
|
|
Median parameters reported
|
10 out of 14
|
14 out of 14
|
|
|
Range
|
6 to 13
|
12 to 14
|
|
|
IQR
|
8-11
|
14-14
|
|
Figure 1: Measurement of length of tumor involving the anal canal and lower rectum on sagittal
T2-weighted image
Figure 2: Measurement of distance of upper rectal tumor from anal verge on sagittal T2-weighted
image
Figure 3: Circumferential rectal wall thickening showing diffusion restriction on diffusion
weighted imaging
Figure 4: Depth of extra-serosal extension on axial T2-weighted image (measured by the orange
colored line shown in the image)
Figure 5: Involvement of mesorectal fascia from 8 to 9 o’ clock position on axial T2-weighted
image as shown by the yellow arrows (Circumferential resection margin status- positive)
Figure 6: Oblique coronal T2-weighted image showing extramural vascular invasion as shown by
the yellow arrowheads
We conducted a retrospective analysis of rectal MRI reports of 100 cases with histologically
proven rectal cancer, comprising of 50 consecutive free-text reports before the template
was introduced and 50 consecutive structured reports after its introduction. The MRI
reports were obtained from the electronic medical record system. Of these, 13 out
of 100 patients had both free text and template reports, serving as their own controls.
Each report was checked for the presence or absence of inclusion of the 14 essential
pre-defined imaging parameters. The actual imaging was not reviewed for the accuracy
of findings reported. One year after the introduction of the structured template,
an anonymous online feedback survey was conducted for the members of the colorectal
tumour board, including senior faculty and fellows on this issue as well. The data
was analyzed using the Fischer’s Exact Test to evaluate whether there was a significant
difference in the percentage of optimal quality reports before and after implementation
of the standardized reporting format, using GraphPad QuickCalcs online software. A
P value of <0.05 was considered to be significant.
Results
Our study included 100 MRI reports from 87 patients (79% males; mean age: 47 years;
range: 19-75). All reports were finalized by dedicated onco-radiology faculty. 50
MRIs were finalized by subspecialty GI onco-radiologists working specifically with
the colorectal disease group, while 50 MRIs were finalized by onco-radiologists not
working with the colorectal group. Overall, the total number of parameters reported
in the MRI reports of these patients increased from a median value of 10 (range 6-13)
to 14 (range 12-14) [Table 1] and [Figure 7]. Out of the 13 patients who had both free text as well as template reports, the
total parameters mentioned in their reports increased from a median value of 9 (range
5-12) to 13 (range 12-14). The common unreported parameters prior to template introduction
included T staging, presence or absence of restricted diffusion, anterior peritoneal
reflection (APR) involvement and the presence or absence of extramural vascular invasion
(EMVI). These were reported in 16%, 22%, 30% and 50%, respectively. These improved
to 98-100% reporting after template introduction.
Figure 7: Number of quality parameters mentioned in the report before and after the implementation
of the template
Maximum improvement was in T staging (16% to 98%) (P < 0.0001), restricted diffusion on DWI (from 22% to 100%) (P < 0.0001) and APR involvement (from 30% to 100%) (P < 0.0001). The most common unreported parameter after template introduction was the
“tumoral T2 signal intensity” (unreported in 4% cases).
The number of parameters mentioned increased from a median value of 9 to a median
value of 14 amongst general onco-radiologists, and from a median value of 10 to a
medial value of 14 amongst the GI onco-radiologists. Our anonymous survey on the rectal
MRI structured template generated 11 responses [Table 2] and [Figure 8].
Table 2
List of questions in our anonymous survey regarding feedback on the rectal MRI structured
template
|
Question
|
|
Have you been exposed to MRI rectum reports both before and after the introduction
of the new template?
Do you think the new template is an improvement in the quality of reporting as compared
to the previous reports?
Do you think the new template is easier to interpret than the free text report used
previously?
Do you feel you a decreased need to talk to the radiologist to clarify the report
after the new template has been introduced?
On a scale of 1-10 (10 being the best), how would you rate the quality of MRI reports
before the introduction of the template?
On a scale of 1-10 (10 being the best), how would you rate the quality of MRI reports
after the introduction of the template?
On a scale of 1-10 (10 being the best), how accurate do you think our current MRI
reports are in providing you with all the relevant findings?
Please give suggestions for further improving the MRI rectum template, or any other
specific feedback and suggestions for the department.
|
Figure 8: Responses to the anonymous online survey conducted for the members of the colorectal
tumor board after introduction of dedicated rectal MRI template
All the 11 participants said that there was a decreased need to talk to the radiologist
to clarify the report after the new template was introduced. 91% of them said that
there was an improvement in the quality of reporting as compared to the previous reports
(the average rating on a scale of 1 to 10 improved from a value of 5 to 6 to a value
of 8 to 9).
The detailed responses can be viewed online at the link below: https://docs.google.com/forms/d/12GlpC0-TeYAz0wkif73ducqd5SeanJkzZPPuHU6rR-A/edit?usp=sharing.
Discussion
Radiologists play a vital role in not just interpreting the imaging findings, but
also in communicating the findings to the referring clinicians. For this, it is important
for the radiology reports to be accurate and to precisely answer the clinical questions.[7] Adoption of structured reporting is the key element in providing optimal quality
reports to the referring physicians and hence ultimately contribute to patient care[8] The recent recommendations suggest a transformation from “prose” reports to reports
with structured templates.[8] Studies have evaluated the impact of structured templates in reporting abdominal
scans,[9] hepatocellular carcinoma reporting[10] as well as prostate imaging.[11] These studies showed a better interdisciplinary communication of imaging findings,
higher comprehensiveness as well as more consistency across the various reports.[9], [10], [11] In rectal cancer, accurate reporting of MRI is essential for determining local tumor
staging and appropriate management.
Our study shows that the introduction of a structured reporting template resulted
in a significant improvement in the reporting of 6/14 essential parameters needed
to be commented on for appropriate patient management. These included vital information
on T staging, EMVI and presence of restricted diffusion which was missing in many
of the initial free text reports, which would have potentially significant impact
on patient care. The improvement was seen in both subspecialty GI onco-radiologist
reports as also ‘general’ onco-radiologist reports. It also resulted in a higher satisfaction
rate amongst the referring oncologists.
Our results are in accordance with earlier studies on structured reporting for rectal
cancer MRI. In a study by Tersteeg et al.[1] which analyzed 492 MRI reports, 6 items were described significantly more frequently
after the implementation of standardized reporting. In another study by Sahni et al.[2] 7/14 quality measures were significantly more frequently documented after the implementation
of the structured template. P. J. Brown et al.[12] analyzed 360 primary rectal cancer staging MRI reports, which showed a statistically
significant increase in the inclusion of certain findings like relationship of tumor
with MRF (from 65.9% in free text reports to 96.3% in template reports), and the presence
of EMVI (from 51.6% in free text reports to 98.7% in template reports). The study
revealed significant improvement in the ‘completeness’ percentage score with use of
the template, a median of 96% inclusion of all variables (IQR: 92-97%), compared to
median 57% inclusion of all variables (IQR- 55–68%) respectively.[12]
There are several limitations to our study, including a relatively small sample size,
lack of assessment of the accuracy of the reports and lack of objective assessment
of the clinical impact of the improved quality reports (although subjective assessment
of satisfaction of the referring oncologists was performed with an anonymous survey).
There was also the possibility of a bias in the survey as majority of the respondents
would be people who were involved in the process of creating the template initially.
Finally, we cannot comment of the utility of structured templates elsewhere in radiology,
as our study was limited to evaluating the use of structured template in rectal cancer
MRI reporting.
In conclusion, the introduction of a structured template for rectal cancer significantly
improved the quality of our reports, across both general and subspecialty radiologists,
as also the satisfaction of referring providers.
