Background and Significance
Colorectal cancer is one of the most common cancers in Western countries.[1]
[2] In addition to lifestyle and eating habits, genetic predisposition contributes to
disease development. The prognosis of colorectal cancer—in terms of recurrence-free
survival, overall survival, and quality of life—is affected by the following three
groups of factors: tumor-specific, therapy-associated, and patient-dependent factors.[3]
[4] Guidelines summarize the clinical experience and scientific evidence, weigh conflicting
points of view against one another, and define the current recommended diagnostic
and therapeutic procedures for a specific disease. Guidelines also define standards
of care in medical practice to facilitate effective and appropriate health care.[5] Evidence-based guidelines have been proven to positively impact the quality of health
care treatment processes.[6] Nevertheless, their impact on patient care remains limited.[7] Guidelines are published in guideline databases or journals that are freely accessible
to medical societies. However, therapeutic adherence to these guidelines limits their
impact on routine patient care in real-world settings.[8] The relevance of a clinical guideline demands a fast and clear provision of knowledge
at the point of care for all treating physicians.[7]
[9]
[10] There are different levels of integration for the extent to which guidelines can
be linked with an electronic health record (EHR).[11] These levels can be measured by the extent to which a guideline is interlinked with
patient-related processes.[12] Another possibility for dissemination is the transfer of the guideline recommendations
into a surgical treatment standard. Clinical decision pathways and algorithms translate
the abstract guideline recommendations into concrete clinical operation procedures.[13] Hence, knowledge extracted from patient data are consistently presented at the human-machine
interface. Based on a patient's EHR, appropriate sections of a formalized guideline
can be assigned and displayed using common terminology. The next suitable treatment
recommendation can be provided based on the patient's current status on the clinical
path. To assign the correct patient position on the clinical decision path, evidence-based
knowledge from the guidelines must be linked to patient-related data, and visualized
at the point of care. The goal is the automatic recommendation of a guideline-based
therapy through properly positioning patients on the clinical path. Based on this
background, we used a generic approach, not limited to any disease, to establish an
automatic clinical decision support system for patients with colorectal cancer based
on their EHR.
Related Research
Several studies have already been performed to support decision-making in oncological
cancer diseases with the aim of optimizing treatment quality and providing therapy
recommendations. Different approaches pursue the idea of monitoring a patient on a
clinical pathway and determining the patient's individual position within a pathway
to provide knowledge at the point of care and to provide clinical guidelines as real-time
decisions.[11]
[14] To improve the management of chronic conditions, Lasorsa et al have addressed specific
psychological aspects to provide patients with a comprehensive and personalized solution.[15] The study examined 22 patients with chronic diseases with the primary aim of providing
a preliminary understanding of their needs in a real context. The study has demonstrated
that tailor-made solutions, which are personalized to the needs of the individual,
are necessary.
In the area of colorectal carcinoma, different approaches to decision support have
been implemented. Militello et al have evaluated a modular decision-support application
for colorectal cancer screening with the goal of evaluating, through a decision-centered
design framework, the ability of the screening and surveillance application to support
primary-care clinicians in tracking and managing colorectal cancer testing.[16] The results have indicated that the screening and surveillance application promises
to close decision support gaps in current EHRs. Suner et al have developed a web-based
decision support tool for rectal cancer treatment, which uses an analytic hierarchy
process and a decision tree.[17] The methodology has been applied to 388 patients and is expected to provide potential
users with decision support in rectal cancer treatment processes and facilitate them
in making projections about treatment options. There is no comparable work in the
field of colorectal cancer that uses Business Process Model and Notation (BPMN) with
Unified Medical Language System (UMLS) annotation as the modeling language for German-language
treatment pathways and algorithms (based on German guidelines).
Objectives
This approach is modeled as rule-based BPMN treatment paths, which are created based
on clinical guidelines and executed on a newly developed open-source workflow software
system[18] to map medical knowledge with patient-specific data. This results in the following
two primary challenges for the derivation of personalized guideline-based treatment
proposals: (1) guidelines exist in a heterogeneous, nonformalized, and nonmachine-readable
form of representation; and (2) there is no link between generic guideline knowledge
and patient-specific information from information systems based on common terminology.
The main goals of this approach are the modeling of machine-readable clinical algorithms
for colon carcinoma and rectal carcinoma annotated by UMLS based on clinical guidelines
and the development of an open-source workflow system for mapping the clinical algorithms
with the patient-specific information to identify and visualize the position of the
individual patient on the treatment algorithm for guideline-based therapy recommendations.
The aim of this approach is to create clinical paths or clinical algorithms based
on an established business process standard, BPMN, which can be annotated by UMLS
concepts. This approach is tested on colon and rectal cancer and could become a generic
approach for all oncological diseases. The annotation of clinical algorithms and patient-specific
data using a uniform terminology allows the establishment of a link between generic
knowledge and patient-specific information. This enables the workflow system to run
the algorithm individually for each patient and to identify and visualize the patient's
position on the path. Since the BPMN standard does not offer UMLS support, this standard
is extended by using UMLS concepts so that the workflow system can interpret these.
Methods
Study Setting
This study was conducted at the West German Cancer Center, University Hospital in
Essen, Germany, and was approved by the Ethics Committee of the University of Essen.
The analyzed cohort included 175 colorectal cancer patients. [Table 1] displays each evaluated patient's dataset according to the German colorectal cancer
guidelines based on the TNM (primary tumor, lymph node status, metastases) criteria.[19] The classification of the Union internationale contre le cancer (UICC) summarizes
these criteria in stages ([Table 2] and [Table 3]). The algorithm reaches the decisions based on the TNM classification and assigns
them to the UICC stages. In gastrointestinal tumors, T describes the depth of tumor
infiltration into the bowel wall, N reflects the number of locoregional lymph nodes
involved, and M describes the presence or absence of distant metastasis.
Table 1
Evaluation dataset
Tumor stages
|
IV
|
III
|
II
|
I
|
Total
|
Colon cancer (1,003 clinical notes)
|
58
|
17
|
11
|
0
|
86
|
Rectal cancer (1,127 clinical notes)
|
65
|
8
|
12
|
4
|
89
|
Total (2,130 clinical notes)
|
123
|
25
|
23
|
4
|
175
|
Table 2
UICC stages of rectal cancer
UICC stage
|
Primary tumor
|
Lymph node status
|
Metastases
|
0
|
Tis
|
N0
|
M0
|
I
|
T1, T2
|
N0
|
M0
|
IIA
|
T3
|
N0
|
M0
|
T3a
|
N1
|
M0
|
T3b
|
N2
|
M0
|
T3c
|
N3
|
M0
|
T3d
|
N4
|
M0
|
IIB
|
T4
|
N0
|
M0
|
IIIA
|
T1–2
|
N1
|
M0
|
IIIB
|
T3–4
|
N1
|
M0
|
IIIC
|
any T
|
N2
|
M0
|
IV
|
any T
|
any N
|
M1
|
Abbreviation: UICC, union internationale contre le cancer.
Table 3
UICC stages of colon cancer
UICC stage
|
Primary tumor
|
Lymph node status
|
Metastases
|
0
|
Tis
|
N0
|
M0
|
I
|
T1, T2
|
N0
|
M0
|
IIA
|
T3
|
N0
|
M0
|
IIB
|
T4a
|
N0
|
M0
|
IIC
|
T4b
|
N0
|
M0
|
IIIA
|
T1–2
|
N1
|
M0
|
T1
|
N2a
|
M0
|
IIIB
|
T3–4
|
N1
|
M0
|
T2–3
|
N2a
|
M0
|
T1–2
|
N2b
|
M0
|
IIIC
|
T4a
|
N2a
|
M0
|
T3–T4a
|
N2b
|
M0
|
T4b
|
N1–2
|
M0
|
IV
|
any T
|
any N
|
M1
|
Abbreviation: UICC, union internationale contre le cancer.
A total of 2,130 German clinical notes, including 698 medical reports, 680 radiology
reports, 380 tumor board protocols, 94 microbiology reports, 260 pathology reports,
and 18 virology reports were evaluated by a physician and a medical computer scientist.
For the validation of the algorithm, a retrospective manual analysis of 175 colorectal
cancer patients was performed. The sample was chosen to define the actual distribution
of tumor stages and was selected by International Statistical Classification of Diseases
and Related Health Problems (ICD) codes from the EHR. No other restrictions were imposed,
and the sample was random.
Standards
The UMLS, introduced by the U.S. National Library of Medicine, is a project that aims
to harmonize the terminology of biomedical resources, such as online databases and
medical dictionaries.[20] The harmonization is done by correlating the concepts and relations of various existing
databases by creating ontologies. The UMLS Concept Unique Identifier (CUI) is used
for a metathesaurus concept in which strings with the same meaning are linked.
The visualization of the clinical algorithm is based on the BPMN, which is a graphical
specification language in computer science and process management.[21] The BPMN was developed by the object management group, which provides a uniform
graphical notation for the specification of business processes. In the literature,
there are several approaches that use the BPMN from the medical area. Most studies
use the BPMN to model clinical pathways, Scheuerlein et al, Andrzejewski et al, and
Beck et al, have agreed that the BPMN is easy to use and quickly understood by all
involved.[22]
[23]
[24] There is also work describing the experience of the collaborative modeling of clinical
pathways by physicians with computer scientists. They report that BPMN training is
relatively quick and intuitive[22] and that health professionals' deeper understanding of clinical processes facilitates
changes and updates of the model.[25] In addition to the easy to understand process modeling and graphical representation,
the elements that can be used in the BPMN are similar to those of the standard elements
of the clinical algorithm specified in the guidelines ([Fig. 1]), thus simplifying the transition from an algorithm to the BPMN.[26]
Fig. 1 Standard elements of the clinical algorithm according to the Medical Center for Quality
in Medicine, Germany.
Study Design
[Fig. 2] illustrates the study design of the personalized guideline-based clinical decision
support system which is divided into three processing steps. Based on the guidelines,
(1) the first step is to model the clinical algorithms for the clinical pictures of
colon carcinoma and rectal carcinoma and annotate them with UMLS concepts; (2) the
patient-specific data from the EHRs are annotated using UMLS concepts, which are based
on the gold standard; (3) in the third and last step, the clinical algorithm can be
run by using the common terminology, and thus the position on this path can be determined
individually for each patient. In the evaluation, the gold standard (the manually
determined guideline-based treatment recommendations of the physicians) is compared
with the determined treatment recommendations of the workflow system. An open-source
workflow system was developed for the processing and visualization of the processes,
as well as the simple graphical representation, of the position of an individual patient
within the algorithm.
Fig. 2 Study design: (A) patient data from the EHRs are manually annotated using UMLS concepts. (B) Based on the guidelines, a clinical algorithm is modeled with the BPMN and annotated
with the same UMLS concepts as the patient data. (C) By using the same terminology, the patient data and the algorithm can be mapped
to determine the patient's position in the algorithm. BPMN, business process model
and notation; EHR, electronic health record; UMLS, unified medical language system.
Clinical Algorithm
Guidelines and clinical algorithms are instruments for quality assurance and process
optimization in the medical domain.[19] These guidelines describe a standardized procedure for the prevention, diagnosis,
therapy, and aftercare of a specific disease at different levels of action. The transfer
of evidence-based knowledge to a structured treatment process is not trivial due to
the different informational content and semantic constructs. In contrast to clinical
texts, no universal gold standard for the guidelines or clinical pathways exists,
as the derived pathway can vary widely depending on the interpretation of the guideline
content. Through this approach, two BPMN-based algorithms were developed, which represent
the guideline-based therapy decision ([Figs. 3] and [4]). To determine the patient's position on the path, the clinical algorithms were
annotated by the same UMLS CUIs as the patient-specific information. Since the BPMN
does not support UMLS-annotated pathways, the notation must be extended by various
elements[27]; [Table 4] lists the extensions that were implemented. The decisions in the clinical path can
be extended by using the UMLS concepts. A distinction was made as to whether a concept
was identified with the respective patient (CUI), whether it was identified and denied
(!CUI), whether the concept was not identified (?CUI), or whether both decision paths
were correct and should be preferred (prefer_this). In particular, tumor stages can
change during the diagnostic course, for example, through a pathological examination.
In such a case, it must be defined in the BPMN path that the path with the higher
stage is preferred. To visualize the content from the guidelines, the hint extension
can be used to display text from the guidelines.
Table 4
UMLS extensions in BPMN
Extension
|
Description
|
CUI
|
Concept identified
|
!CUI
|
Concept identified and negated
|
?CUI
|
Concept not identified
|
prefer_this
|
Prefers this path if the CUIs are identified in both decision paths
|
Hint
|
Information on the level of recommendation
|
Abbreviations: BPMN, business process model and notation; EHR, electronic health record;
UMLS, unified medical language system.
Fig. 3 BPMN-based algorithm: rectal cancer. BPMN, business process model and notation.
Fig. 4 BPMN-based algorithm: colon cancer. BPMN, business process model and notation.
The syntax is described using the example of the decision of the microsatellite status.
[Fig. 5] illustrates how the decision can be converted into the BPMN using the CUI with the
help of the BPMN extensions. As an example, therapy recommendation K10 is chosen if
a patient has been identified as having CUI C4321493 (microsatellite stability) or
if CUI C0920269 has been negated (no microsatellite instability). Therapy recommendation
K11 is selected if CUI C0920269 (microsatellite instability) has been identified in
a patient, or if CUI C4321493 has been negated (no microsatellite stability). If both
CUIs C4321493 and C0920269 are not identified as negated or jointly negated, no decision
can be made by the algorithm.
Fig. 5 Implementation example MSI/MSS. MSI, microsatellite instability; MSS, microsatellite
stability; CUI, concept unique identifier.
Annotation of Patient Data
The gold standard was defined by a clinical oncologist regarding the information needed
to derive a guideline-compliant recommendation. Based on the clinical algorithm, the
UMLS concepts were extrapolated to determine the position on the path. Accordingly,
an annotation dataset ([Appendix A]—annotation_dataset.pdf) was developed for a computer scientist and the oncologist
to manually annotate the patient data comprising 2,130 clinical notes. To evaluate
only the clinical algorithm and not the quality of the available patient data, these
data were preprocessed and structured. To use this solution in regular clinical operations,
unstructured data would have to be automatically preprocessed, such as by text mining.
Appendix A
Annotation dataset
Item
|
Term
|
CUI
|
T0
|
T0
|
C0475371
|
T1
|
T1
|
C0475372
|
T2
|
T2
|
C0475373
|
T3
|
T3
|
C0475374
|
T4a
|
T4a
|
C0475395
|
T4b
|
T4b
|
C0475396
|
pT0
|
pT0
|
C0332390
|
pT1
|
pT1
|
C0332391
|
pT2
|
pT2
|
C0332392
|
pT3
|
pT3
|
C0332393
|
pT4a
|
pT4a
|
C1711137
|
pT4b
|
pT4b
|
C1711138
|
N0
|
N0
|
C0441959
|
N1
|
N1
|
C0441962
|
N2a
|
N2a
|
C0445079
|
N2b
|
N2b
|
C0445080
|
pN0
|
pN0
|
C0332396
|
pN1
|
pN1
|
C0332397
|
pN2a
|
pN2a
|
C2733134
|
pN2b
|
pN2b
|
C2733178
|
M0
|
M0
|
C0445034
|
M1a
|
M1a
|
C0445036
|
M1b
|
M1b
|
C0445064
|
M1c
|
M1c
|
C0445037
|
pM0
|
pM0
|
C0332402
|
pM1a
|
pM1a
|
C1711115
|
pM1b
|
pM1b
|
C1711116
|
pM1c
|
pM1c
|
C1711117
|
MSI
|
Microsatellite instability
|
C0920269
|
MSS
|
Microsatellite stable
|
C4321493
|
RAS
|
retrovirus-associated DNA sequences (RAS)
|
C0034677
|
BRAF
|
BRAF gene
|
C0812241
|
RES
|
Resectable
|
C1514888
|
ANO
|
Rectum (<12 cm from ANO)
|
C0034896
|
IT
|
Intensive care
|
C0085559
|
TL
|
Tumor burden
|
C1449699
|
RP
|
Rapid progress
|
C9999999
|
TS
|
Tumor/symptoms
|
C3846098
|
OK
|
Organ compilation
|
C9999998
|
HR
|
High risk
|
C0475283
|
SRES
|
secondary resectable
|
C4725865
|
Gold Standard Evaluation
To evaluate the therapy recommendations, the endpoints of the algorithm were numbered
consecutively and determined manually by an oncologist for each patient ([Table 5]). The algorithms resulted in 14 possible therapy decisions for rectal cancer and
12 possible therapy decisions for colon cancer ([Figs. 3] and [4]). In the analysis of the data for colon cancer, there were four cases in which no
final therapy decision could be made based on the available data. In these cases,
the final pathological findings on the microsatellite instability (MSI) status were
not yet available. In the analyzed patient collective, cases in which the MSI was
absent occurred exclusively in patients with colon carcinoma. Therefore, the algorithm
had to stop the decision process in these cases. Depending on the MSI status, the
result was an endpoint of either C10 (microsatellite stable) or C11 (microsatellite
instable). In addition, these endpoints were assigned to different TNM stages.
Table 5
Gold standard evaluation dataset for colon and rectal cancer
Rectal cancer endpoint
|
Tumor stage
|
No.
|
Colon cancer endpoint
|
Tumor stage
|
No.
|
R1
|
IV
|
19
|
C1
|
IV
|
2
|
R2
|
IV
|
9
|
C2
|
IV
|
26
|
R3
|
IV
|
2
|
C3
|
IV
|
10
|
R4
|
IV
|
4
|
C4
|
IV
|
27
|
R5
|
IV
|
17
|
C5
|
III
|
4
|
R6
|
IV
|
7
|
C6
|
III
|
2
|
R7
|
III
|
8
|
C7
|
III
|
2
|
R8
|
III
|
5
|
C8
|
II
|
1
|
R9
|
III
|
0
|
C9
|
II
|
1
|
R10
|
III
|
4
|
C10
|
II
|
3
|
R11
|
III
|
0
|
C11
|
II
|
3
|
R12
|
II
|
5
|
C12
|
I
|
4
|
R13
|
II
|
6
|
MSI
|
II
|
4
|
R14
|
I
|
0
|
|
|
|
Total
|
|
86
|
Total
|
|
89
|
Abbreviations: C1–12, endpoint for colon cancer (treatment recommendation); MSI, microsatellite
instability decision point; R1–14, endpoint for rectal cancer (treatment recommendation).
Statistical Analysis
For this approach, the treatment recommendations were compared with the gold standard
of the respective endpoints and the associated TNM stages. The following values were
determined: the precision or positive predictive value (P), recall or true positive rate (R), and F1 measure (F1), for which recall and precision were equally weighted. The F1 score is the harmonic
mean of the precision and recall, where an F1 score reaches its best value at 1 and
worst at 0.
A Chi-squared test was applied to evaluate the statistical independence of the differences
in the distribution between colon and rectal cancer. The statistical significance
was determined to be p < 0.05, and a 95% confidence interval was calculated.
Results
The colorectal cancer cohort dataset included 175 patients. There were 89 colon cancer
cases and 86 rectal cancer cases. The dataset contained 2,130 clinical notes. The
mean age of the patients in the dataset was 62.9 years, and 45% of the patients were
female. [Tables 6] and [7] detail the treatment recommendation performance of the clinical algorithm compared
with the gold standard. Using this approach for therapy recommendation, the algorithm
achieved a precision value of 87.64% for colon cancer and 84.70% for rectal cancer
with recall values of 87.64 and 83.72%. For the clinical algorithm of colon carcinoma,
a total of 89 patients with confirmed diagnoses were retrospectively analyzed. [Table 7] displays the correct (true positive) and incorrect (false positive and false negative)
treatment recommendations for the respective TNM stages and treatment decisions of
colon cancer (K1–K12 and MSI). The patients with stages I and II were completely and
correctly identified (100% recall and 100% precision). Patients with stages III and
IV were more weakly identified compared with the other stages in terms of treatment
recommendations. This can be attributed to the significantly higher complexity (more
decision points) of the stage III and IV algorithms. For the clinical algorithm of
rectal cancer, a total of 87 patients with confirmed diagnoses were retrospectively
analyzed. [Table 6] displays the respective TNM stages and treatment decisions (R1–R14). In contrast
to colon carcinoma, the rectal carcinoma algorithm identified the weakest results
in cases with stage IV (79% recall) and stage III (73% precision) and the best results
for stage II. The incorrectly determined treatment recommendations in stage III are
conspicuous. This can be traced back to the path design of rectal carcinoma because,
in contrast to colon carcinoma in stages II and III, pathohistological staging is
performed, which cannot be clearly assigned without a chronological component, which
has not been taken into account in this work.
Table 6
Evaluation of rectal cancer treatment recommendations
Endpoints
|
GS
|
TP
|
FP
|
FN
|
R
|
P
|
F1
|
Stage IV
|
58
|
46
|
6
|
12
|
0.79
|
0.88
|
0.84
|
R1
|
19
|
16
|
2
|
3
|
0.84
|
0.89
|
0.86
|
R2
|
9
|
7
|
1
|
2
|
0.78
|
0.88
|
0.82
|
R3
|
2
|
2
|
2
|
0
|
1.00
|
0.50
|
0.67
|
R4
|
4
|
3
|
0
|
1
|
0.75
|
1.00
|
0.86
|
R5
|
17
|
13
|
1
|
4
|
0.76
|
0.93
|
0.84
|
R6
|
7
|
5
|
0
|
2
|
0.71
|
1.00
|
0.83
|
Stage III
|
17
|
16
|
6
|
1
|
0.94
|
0.73
|
0.82
|
R7
|
8
|
7
|
1
|
1
|
0.88
|
0.88
|
0.88
|
R8
|
5
|
5
|
2
|
0
|
1.00
|
0.71
|
0.83
|
R9
|
0
|
0
|
0
|
0
|
–
|
–
|
–
|
R10
|
4
|
4
|
3
|
0
|
1.00
|
0.57
|
0.73
|
R11
|
0
|
0
|
0
|
0
|
–
|
–
|
–
|
Stage II
|
11
|
10
|
2
|
1
|
0.91
|
0.83
|
0.87
|
R12
|
5
|
4
|
0
|
1
|
0.80
|
1.00
|
0.89
|
R13
|
6
|
6
|
2
|
0
|
1.00
|
0.75
|
0.86
|
Stage I
|
0
|
0
|
0
|
0
|
–
|
–
|
–
|
R14
|
0
|
0
|
0
|
0
|
–
|
–
|
–
|
Total
|
86
|
72
|
14
|
14
|
0.84
|
0.85
|
0.84
|
Abbreviations: F1, F measure; FN, false negatives; FP, false positives; GS, gold standard;
P, precision or positive predictive value; R, recall or true positive rate; TP , true
positives.
Table 7
Evaluation of colon cancer treatment recommendations
Endpoints
|
GS
|
TP
|
FP
|
FN
|
R
|
P
|
F1
|
Stage IV
|
65
|
55
|
10
|
10
|
0.85
|
0.85
|
0.85
|
C1
|
2
|
1
|
1
|
1
|
0.50
|
0.50
|
0.50
|
C2
|
26
|
19
|
0
|
7
|
0.73
|
1.00
|
0.84
|
C3
|
10
|
9
|
2
|
1
|
0.90
|
0.82
|
0.86
|
C4
|
27
|
26
|
7
|
1
|
0.96
|
0.79
|
0.87
|
Stage III
|
8
|
7
|
1
|
1
|
0.88
|
0.88
|
0.88
|
C5
|
4
|
3
|
0
|
1
|
0.75
|
1.00
|
0.86
|
C6
|
2
|
2
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C7
|
2
|
2
|
1
|
0
|
1.00
|
0.67
|
0.80
|
Stage II
|
12
|
12
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C8
|
1
|
1
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C9
|
1
|
1
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C10
|
3
|
3
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C11
|
3
|
3
|
0
|
0
|
1.00
|
1.00
|
1.00
|
MSI
|
4
|
4
|
0
|
0
|
1.00
|
1.00
|
1.00
|
Stage I
|
4
|
4
|
0
|
0
|
1.00
|
1.00
|
1.00
|
C12
|
4
|
4
|
0
|
0
|
1.00
|
1.00
|
1.00
|
Total
|
89
|
78
|
11
|
11
|
0.88
|
0.88
|
0.88
|
Abbreviations: F1, F measure Equations; FN, false negatives; FP, false positives;
GS, gold standard; P, precision or positive predictive value; R, recall or true positive
rate; TP, true positives.
The Chi-squared test under the null hypothesis that there is no association between
colon and rectal cancer (p < 0.05) indicates a strong correlation between the results for colon and rectal cancer
even though the results differ in certain tumor stadiums. The null hypothesis that
there is no association can be rejected, meaning that the results of the two clinical
pictures indicate a strong similarity.
Discussion
This study qualitatively assessed the therapy decision of clinical algorithms as part
of a clinical pathway. The results indicate that automatically positioning a patient
on the decision path is possible. It can be deduced that nonextensive tumor stages
with fewer decision points achieve higher accuracy compared with complex stages. Since
the dataset analyzed was provided by a university hospital, most of the cases feature
highly complex patients who are frequently treated within clinical trials. Based on
this, the failure of the developed algorithms to deliver the correct results can be
attributed to various reasons, for example, patients treated within clinical trials
often deviate from the guideline-based path due to new treatment methods. In addition,
patients sometimes decline different therapies that are recommended by the developed
clinical algorithm. Furthermore, some clinical decisions are made by the interpretation
of radiological examinations, such as the resectability of metastasis. For this purpose,
image data that have not been considered in the context of this work must be analyzed,
such as by image mining. The aforementioned misinterpretations by the clinical algorithms
cannot be recognized by the approach presented here, since a therapy recommendation
can only be issued after the definition of a guideline.
The analysis of the results demonstrates that the current possibilities of path design
are not yet sufficient. For cases that initially have a low TNM stage and are reclassified
to a higher TNM stage during the diagnostic procedures, an extension of the path design
becomes necessary, and a chronological interpretation of the results must be presented
during the hospital stay. If pathohistological staging was performed in the later
course of treatment, this information had no chronological component. Since this information
was available to the algorithm at the beginning of the derivation of the therapy recommendation,
the algorithm identified the higher stage because the pathohistological staging had
a higher stage than the clinical staging. In some cases, for example, in rectal cancer,
a different path was chosen for patients other than the gold standard but with the
same therapy recommendation at the end (adjuvant chemotherapy). The incorrectly identified
cases in the colon carcinoma algorithm can also be traced back to the missing chronological
component of the information. Here, it was decided whether an intensive therapy was
possible in the cases that had not been correctly determined, which had changed over
the course of the treatment. For cases that initially have a low-TNM stage and are
classified into a higher TNM stage during diagnosis or treatment, the algorithms must
be extended and a chronological interpretation of the results determined during the
hospital stay. Cases in which stage IV was not identified correctly are particularly
critical. Since the therapeutic approach and the 5-year survival rate for stage-IV
colorectal cancer differ considerably from those in the lower stages, any incorrect
therapy recommendation would have significant consequences. In four cases, a stage-III
tumor was determined, and in one case, a stage-I tumor was identified, even though
these cases were stage IV. If the algorithm detected stage-IV disease, it was correct
in all cases, even if the correct therapy decision was not always determined. In addition,
complex cases with secondary tumors could not be allocated to guideline-based treatment.
Further decisions and a more complex path design are needed to map these cases to
achieve better outcomes.
Conclusion
Clinical practice, as well as research and quality assurance, benefits from clear
clinical information using common terminology such as UMLS. This common terminology
is necessary for the consistent reuse of data and the support of semantic interoperability.
To derive treatment recommendations from guidelines based on patient-specific data,
knowledge from the guidelines is combined with patient-specific information. A further
approach would be to display treatment-relevant information in archetype-based templates
in addition to decision support from the guidelines. Using the examples of colon and
rectal cancer, we demonstrated that the model developed in this study can structure
the given information from a guideline and could easily be included for use as a clinical
decision-support tool in treatment pathways. To make the path available at the point
of care, it is necessary to link it to the patient data and to integrate it into a
hospital information system.[28]
[29]
Clinical Relevance Statement
Evidence-based guidelines can have a positive impact on the quality of medical care,
but their influence on patient care in Germany is still very small. With the help
of workflow software, the physician could be shown guideline-based treatment recommendations
tailored to the patient so that interested physicians do not have to actively search
and study the contents of the guidelines. This approach enables a fast, simple, and
clear provision of evidence-based knowledge at the point of care.