Dukes' classification
Dukes' classification is a system developed by Dr. Cuthbert E. Dukes in 1932 for categorizing operable colon and rectal cancer based on the extent of the disease and its prognosis. This classification includes stages A, B, and C, and has been modified over time to incorporate additional sub-stages such as B1, B2, C1, and C2, and a fourth stage, D. Each stage corresponds to the severity of cancer, with Stage A indicating minimal disease and a higher survival rate, while Stage D represents advanced cancer that has metastasized, denoting a poorer prognosis. The classification is crucial for guiding treatment decisions, with more aggressive therapies likely for early-stage patients and palliative care for those in Stage D. Although Dukes' classification has been historically significant, it has largely been supplanted by the TNM staging system, which offers a more detailed assessment of tumor size, lymph node involvement, and metastasis. Recent advancements also include molecular classifications and concepts like epithelial-mesenchymal transition (EMT) for further refining cancer staging.
Subject Terms
Dukes' classification
DEFINITION: Dr. Cuthbert E. Dukes (1890-1977) was a pathologist who developed the classification for operable colon or rectal cancer. He began his studies at St. Mark’s Hospital in 1922 and published the Dukes’ classification in 1932. Through many years of examining the various clinical stages and prognoses of patients diagnosed with rectal cancer, he was able to develop a pathological classification system that reflected the prognosis based on three categories: A, B, and C. Dukes’ classification has been modified to include B1 and B2 as well as C1 and C2. Dr. Vernon Astler and Dr. Fredrick Coller later modified Dukes’ classification to include a fourth stage, D.
Cancers diagnosed: cancers
Why performed: Patients diagnosed with cancer of the colon or rectum will have treatment and therapy guided by the Dukes’ classification system. Patients who have been classified as Stage A may receive more aggressive treatment; those patients classified as Stage D may receive only palliative treatment.
Patient preparation: Dukes’ classification is used for a patient who has had a of the tumor. The biopsy may be obtained surgically or through a colonoscopy or a CT-guided biopsy. The patient will have nothing to eat or drink for at least eight hours before any of these procedures. If the cancer is in the lower gastrointestinal (GI) tract, then the patient will have to complete a bowel prep, which includes drinking a liquid to cause the stool in the GI tract to be evacuated. If the biopsy will be taken surgically, then the patient may have the skin shaved at the site.
Steps of the procedure: The patient will be positioned for comfort. If in the operating room, then the patient will be given general anesthesia. If a sample is to be taken by CT-guided biopsy or colonoscopy, then the patient may be given medications to cause sleepiness and block any pain. Once the patient is positioned and medication is given, the entrance site for the biopsy is cleansed with an appropriate solution. The physician will obtain the biopsy and then place the sample either in a vial with a preservative or on a slide for viewing. The samples will then be sent to the pathologist so that diagnosis and classification can be done.
After the procedure: The patient will be monitored after the procedure for signs of bleeding or pain for a couple of hours. A patient who has completely awakened from the medication-induced sleep and is able to tolerate fluids is able to be driven home by a friend or family member.
Risks: Infections, pain, and bleeding are all risks of obtaining a biopsy for Dukes’ classification.
Results: Dukes’ classification is based on the pathology of the cancer. A patient will have a biopsy of the disease site, and the pathologist will be able to stage the disease based on the defined classification stage. A better prognosis, or five-year survival rate, is directly related to the stage of the disease of the patient. Stage A indicates minimal disease and a high five-year survival rate. Stages B and C indicate that the disease has progressed into the surrounding tissue, and the survival rate is decreased. Stage D indicates that the disease has spread, or metastasized, to another site. Stage D is directly related to a poor prognosis or a poor chance of a five-year survival rate.
Although the Dukes’ classification system is still used in the twenty-first century, it has largely been replaced by the TNM staging system. In this system, the T refers to the size and extent of the tumor, the N refers to how many lymph nodes are affected, and the M determines if the cancer has metastasized and spread to other parts of the body. Like Dukes’ classification, different letter-number combinations are assigned to reflect the state and severity of the cancer. In the 2020s, molecular classifications and the epithelial-mesenchymal transition (EMT) concept emerged as new classification methods.
Banias, Laura, et al. "From Dukes-MAC Staging System to Molecular Classification: Evolving Concepts in Colorectal Cancer." International Journal of Molecular Sciences, vol. 23, no. 16, 2022, doi.org/10.3390/ijms23169455. Accessed 12 June 2024.
“Cancer Staging.” National Cancer Institute, 14 Oct. 2022, www.cancer.gov/about-cancer/diagnosis-staging/staging. Accessed 12 June 2024.
“Definition of Dukes Classification - NCI Dictionary of Cancer Terms.” National Cancer Institute, www.cancer.gov/publications/dictionaries/cancer-terms/def/dukes-classification. Accessed 12 June 2024.