Esophageal Cancer Stages
The staging system is of major importance for any type of cancer including esophageal cancer. In order to precisely determine the stage of the disease medical experts take into consideration several factors such as histological type and grade of the tumor, spread of the cancer to regional/distant lymph nodes or nearby organs, the extent of infiltration of the esophageal wall etc. Staging is what determines the future therapy and also predicts the outcome of the disease.
The tumor per se is diagnosed with the assistance of several tests and exams. Initially, one usually undergoes upper gastrointestinal endoscopy. This approach is capable of visualizing the inner surface of the organ and easily detects the tumor. During the procedure doctors take samples of the suspicious tissue and send them for pathohistological examination. Upper gastrointestinal endoscopy is also a powerful tool for the diagnosis of Barret's esophagus, which is a precancerous condition, eventually progressing into invasive esophageal cancer.
Apart from endoscopy, once the tumor is histological confirmed patients undergo CT scan, MRI or even PET scans. These imaging techniques provide with the information about the size of the tumor and also detect the extent of its infiltration. The techniques additionally identify enlarged lymph nodes and metastases.
By visualizing the organ, the tumor and evaluating the extent of the disease doctors make decision regarding the treatment.
In the beginning the tumor is small and restricted to the wall of the esophagus. Later, it penetrates all its layers, infiltrates the nearby organs and regional lymph nodes while dissemination of cancer cells leads to metastatic lesions in the lungs, bones and other organs.
TNM classification is definitely the basis for staging esophageal cancers. This abbreviation stands for tumor (T), lymph node involvement (N) and the presence or absence of metastases (M).
As for T part of TNM classification, there are several options. T0 stands for no evidence of the primary tumor while T1-4 confirm the presence of the tumor and its spread through the esophageal layers. There is also Tis (carcinoma in situ) which is actually a non-invasive esophageal cancer limited to the surface of the organ (the mucosa).
When it comes to node involvement, classification recognizes two states, N1 when the cancer has spread to regional lymph nodes and N0 when nodal involvement is ruled out.
And finally, the presence of metastases is classified as M1 , while M0 stands for absence of cancer cell dissemination.
There are 5 stages of esophageal cancer. In stage 0 the cancer is restricted to the epithelium layer and the rest of the esophageal wall is cancer-free. So, the tumor remains inside the organ sparing regional lymph nodes and distant organs.
In the first stage of the disease the esophageal cancer grows further infiltrating the lamina propria but still remaining inside the organ, not affecting the lymph nodes.
Further progression of the disease (stage II esophageal cancer) is characterized by infiltration of the muscle layer and spread beyond the organ. Nearby lymph nodes are affected in most cases but there is no further dissemination of cancer cells.
In stage III of esophageal cancer the cancer infiltrates the nearby organs and tissues along with regional lymph nodes. Fortunately, there are no cancer cells in the lungs, bones or other distant organs but the tumor is practically inoperable and the prognosis is not very good.
Final Stage of Esophageal Cancer
Final stage of esophageal cancer or stage IV of the disease occurs when the tumor is located not only inside the esophagus and nearby organs but is also confirmed in other organs of the body where clumps of cancer cells form metastases of various size. The five-year rate of survival in these patients is no greater than 2.8 % since dissemination does not respond well to any of the available treatments. What is more, patients in the terminal stage are anorexic, lose their appetite and subsequently lose their strength against the disease and develop a whole variety of different complications.
Even though it sounds horrible, terminal stage is actually introduction into inevitable lethal outcome. Depending on the affected organs patients may deal with severe pain (bone metastases), swallowing difficulties or complete inability to swallow solids or liquids (obstruction of the esophagus by the tumor) or they experience respiratory problems (lung metastases). Sometimes the cancer infiltrates the nearby large blood vessels and is blamed for rapid death due to exsanguination. Hoarse voice, frequent hiccups and throat pain are several more problems these patients have to deal with.
All in all, the terminal stage of esophageal cancer is hard to withstand and requires plenty of supportive care. Such patients are treated palliatively, where the goal of the treatment is to alleviate the symptoms of the disease which are in the majority of cases practically unbearable.