Cohort Definition Name: Primary adenocarcinoma of colon or rectum, MSI-H or dMMR
Contributor name: Andreas Weinberger Rosen
Contributor OrcId: 0000-0001-9990-8155
Logic Description: First event Primary adenocarcinoma of the colon or rectum, with MSI-H or dMMR molecular subtype
Recommended study application: exposure.
Assertion statement: This cohort definition was executed on at least one real person-level observational health data source and resulted in a cohort with at least 1 person.
Submitted cohort definition:
Primary adenocarcinoma of colon or rectum, MSI-H or dMMR.txt (51.9 KB)
Target Clinical Description
Colorectal cancer, primarily an adenocarcinoma, stands as the most prevalent malignant tumor affecting the intestinal tract. Originating in the epithelial cells that line the colon or rectum, the disease can escalate into a full-fledged malignant tumor through various molecular mechanisms. The disease manifests differently based on its anatomical location, its size, and its stage of development.
Presentation of Colorectal Cancer
Common Symptoms:
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Hematochezia or blood in the stool -
Diarrheal episodes or constipation -
Sensation of incomplete bowel evacuation -
Abdominal discomfort or pain -
Unintentional weight loss -
Nocturnal sweating -
Anemia
Some patients may not display symptoms and are often diagnosed either via screening programs or incidental findings during other medical evaluations.
In some instances, colorectal cancer can escalate into an emergency scenario, leading to complications like bowel obstruction, acute lower gastrointestinal bleeding, or even bowel perforation.
Assessment for Colorectal Cancer
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Colonoscopy for macroscopic evaluation and biopsy collection -
Histopathology of the biopsy tissue serves as a cornerstone for diagnosis -
Various imaging modalities such as CT, PET, and MRI for clinical staging -
Histological evaluation of surgical or metastatic samples for pathological staging
Differential Diagnosis of Colorectal Cancer
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Other intestinal neoplasms like neuroendocrine tumors or advanced polyps -
Diverticular disease -
Hemorrhoidal issues -
Anal fissures -
Irritable Bowel Syndrome (IBS) -
Inflammatory Bowel Disease (IBD)
Treatment Plan for Colorectal Cancer
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For localized or regionally-confined cancers, surgical resection along with the affected intestinal segment remains the standard care, often supplemented by neoadjuvant or adjuvant therapies like chemotherapy or radiation. -
In cases of solitary metastasis, radical surgery may be augmented by radiofrequency ablation, stereotactic radiation, or additional surgeries for metastatic lesions, aiming for curative outcomes. -
For those without curative options, palliative measures, including oncological treatments and surgical interventions, are employed to improve symptoms and extend life expectancy. -
Patients with specific molecular profiles, such as 'deficient mismatch repair' or high microsatellite instability, may benefit from treatments involving immune checkpoint inhibitors.
Prognosis for Colorectal Cancer
The prognosis hinges on multiple factors, most notably the stage at diagnosis the MSI-H / dMMR phenotype appears to have better prognosis compared to MSI-L / pMMR
Assignment for Peer Review:
Peer review of the phenotype would be more than welcome