Types of Cancer: The different stages and grades

There are many different types of cancer, each of which is named after the type of cell in which it starts. Some of the most common types of cancer include:

• Breast cancer
• Colorectal cancer
• Lung cancer
• Prostate cancer
• Melanoma
• Leukemia
• Lymphoma
• Non-Hodgkin lymphoma
• Hodgkin lymphoma
• Myeloma
• Bladder cancer
• Kidney cancer
• Ovarian cancer
• Endometrial cancer
• Thyroid cancer
• Pancreatic cancer
• Esophageal cancer
• Stomach cancer
• Liver cancer
• Brain cancer
• Bone cancer
• Soft tissue cancer

Types of Cancer Stages

Most types of cancer are staged using a number-stage system, such as the TNM system, which divides cancers into four stages: stage I to stage IV. 

Some cancers may also have stage 0, which describes cancer in situ, meaning it is still located in the place it started and has not spread to nearby tissues. 

The specific stage of a cancer is determined by various factors, including the tumor’s size, location, and whether it has spread to lymph nodes or other parts of the body.

The Four Stages of Cancer

Stage 0: Cancer is in situ, meaning it has not spread to nearby tissues. This stage is often curable, and surgery can usually remove the entire tumor.

Stage I: The cancer is small and localized to one area, and it has not spread to lymph nodes or other tissues. This stage is also called early-stage cancer.

Stage II and Stage III: These stages indicate that the cancer has grown larger and may have spread to nearby tissues and lymph nodes, but it has not spread to other parts of the body.

Stage IV: The cancer has spread to other organs or areas of the body. This stage is also called advanced or metastatic cancer.

The stage of a cancer is determined at the time of diagnosis and initial treatments and does not change over time. It helps doctors understand a person’s medical progress, develop a prognosis, and plan the most appropriate treatment.

The Four Grades of cancer

Types of cancer grade are a measure of how abnormal cancer cells and tissues appear under a microscope compared to healthy cells. It provides information about the aggressiveness and growth rate of the cancer.

1. Grade 1 (Well-differentiated): Cancer cells closely resemble normal cells and grow slowly.

2. Grade 2 (Moderately differentiated): Cancer cells are less like normal cells and grow at a moderate rate.

3. Grade 3 (Poorly differentiated): Cancer cells look abnormal and may grow or spread more aggressively.

4. Grade 4 (Undifferentiated): Cancer cells are highly abnormal, grow rapidly, and may have a higher likelihood of spreading.

The specific grading system may vary depending on the types of cancer, but most tumors are graded using a scale of 1 to 4, with higher numbers indicating more abnormal and aggressive cells.

Cancer grade, along with other factors such as stage and a patient’s overall health, helps doctors determine the best treatment plan and predict the cancer’s behavior and prognosis.

Also read: The Best Treatment Modalities For Breast Cancer

FAQs

What is the difference between cancer stages and grades?

Cancer stages and grades are two different aspects of understanding and classifying cancer. While both provide important information about cancer, they measure different characteristics of the disease.

Cancer Stages:

• Staging describes the size of the tumor and how far it has spread from its original location.
• Staging helps doctors determine the best treatment plan and predict a patient’s prognosis.
• Staging is often based on the TNM system, which considers the tumor’s size (T), lymph node involvement (N), and metastasis (M).
• Stages range from 0 to IV, with higher numbers indicating more advanced cancer.

Cancer Grades:

• Grading describes the appearance and behavior of the cancerous cells.
• Grading is determined by examining the cells under a microscope and comparing them to normal cells.
• Lower-grade cancers have cells that resemble normal cells and grow more slowly, while higher-grade cancers have more abnormal cells and grow faster.
• The most common grading system uses grades 1 to 3, with 1 being low-grade and 3 being high-grade.

In summary, cancer stages provide information about the extent of the disease, while cancer grades describe the characteristics of the cancer cells themselves. Both staging and grading are important for developing a treatment plan and predicting a patient’s prognosis.

How does cancer grade affect prognosis?

Cancer grade, which describes how abnormal cancer cells look under a microscope, can significantly affect a patient’s prognosis. The grade provides clues about how quickly the cancer is likely to grow and spread. Here’s how cancer grade can impact prognosis:

Low-grade cancer (Grade 1): These types of cancer have cells that closely resemble normal cells and tend to grow slowly. Patients with low-grade cancers often have a better prognosis, as these tumors are less aggressive and less likely to spread.

Intermediate-grade cancer (Grade 2): Cancer cells in Grade 2 tumors are less like normal cells and grow at a moderate rate. The prognosis for patients with Grade 2 cancers can vary depending on other factors, such as the cancer’s stage and the patient’s overall health.

High-grade cancer (Grade 3 and 4): Grade 3 and 4 types of cancer have cells that look more abnormal and may grow or spread more aggressively. Patients with high-grade cancers often have a poorer prognosis, as these tumors are more likely to grow rapidly and spread to other parts of the body.

It’s important to note that cancer grade is just one of the factors that doctors consider when determining a patient’s prognosis. Other factors, such as the cancer’s stage, genetic features, the patient’s age, and overall health, also play a role in predicting the disease’s outcome.

Can cancer grade change over time and affect prognosis?

Cancer grade can change over time, and this can have an impact on prognosis. The grade of a cancer is determined by looking at the cancer cells under a microscope, using tissue from a biopsy, or after cancer surgery. Here’s how changes in cancer grade can affect prognosis:

Grade change after biopsy and surgery: Sometimes, the grade given to cancer after a biopsy can change after surgery. This is because after surgery, there’s more tissue for the pathologist to examine, which can provide more detailed information about the cancer. A change in grade may lead to a reassessment of the treatment plan and prognosis.

Different grades within a tumor: Different areas within a tumor can have cancer cells with different grades. However, the tumor is usually graded based on the highest grade seen anywhere within the tumor. This means that if a higher-grade area is present, it may have a greater impact on prognosis and treatment decisions.

Impact on treatment options: The grade of a cancer is used to help plan treatment, and a higher-grade cancer may require faster or more intensive treatment. For example, if a cancer is initially diagnosed as a lower grade but later changes to a higher grade, the treatment plan may be adjusted to address the more aggressive nature of the cancer.

Also read: What Is A Brain Tumor Symptoms, Causes And Treatments?

Prognostic implications: A higher-grade cancer is generally more aggressive, grows and spreads more quickly, and may have a poorer prognosis. Therefore, if a cancer’s grade changes to a higher grade over time, the prognosis may be affected, and the patient’s chances of survival may be lower.

How often should cancer grade be re-evaluated?

The frequency of re-evaluating the cancer grade can vary depending on the type and stage of cancer, as well as the specific treatment plan and individual patient factors.

In general, cancer grade is not re-evaluated as frequently as cancer stage, as it is determined based on the initial biopsy or surgical specimen. 

However, in some cases, a re-evaluation of the grade may be necessary if there are significant changes in the tumor’s appearance or behaviour.

Protocol-specific guidelines: The frequency of tumor re-evaluation during treatment should be protocol-specific and adapted to the type and schedule of treatment. This means that different treatment protocols may have different recommendations for how often the cancer grade should be re-evaluated.

Follow-up response assessment: For some types of cancer, such as those being treated with immunotherapeutics, a follow-up response assessment every 6–12 weeks is recommended. The frequency of re-evaluating the cancer grade may be similar to the frequency of these follow-up assessments.

Phase II studies: In the context of phase II studies where the beneficial effect of therapy is not known, a follow-up of every other cycle (i.e., 6–8 weeks) may be a reasonable norm for tumor re-evaluation. Smaller or greater time intervals than these could be justified in specific regimens or circumstances.

End of treatment: After the end of treatment, the need for repetitive tumor evaluations depends on whether the phase II trial has the goal of assessing long-term outcomes. In some cases, the cancer grade may be re-evaluated as part of the post-treatment follow-up to assess the long-term effectiveness of the treatment.

Can the cancer stage change over time?

The stage of cancer does not change over time, even if the cancer progresses or goes into remission. The original stage assigned at the time of diagnosis remains the same, and any new information about the cancer’s progression is added to the original stage.

Restaging may be done if the cancer recurs (comes back) or progresses (grows or spreads without ever having gone away completely). This information can help guide decisions about further treatment. However, the original stage of the cancer does not change.

Understanding the stage of cancer is important for doctors to plan the best treatment, predict the course of the disease, and communicate with other healthcare professionals about a person’s cancer. Referring to the original stage also allows researchers to track and compare survival rates for patients who were diagnosed at the same stage.

What are the reasons for restaging cancer?

Restaging cancer may be necessary for several reasons:

Monitoring treatment response: Re-staging can help determine how well a patient is responding to treatment, such as chemotherapy, radiation therapy, or immunotherapy. This information can guide decisions about further treatment options, such as surgery or additional therapies.

Detecting recurrence or progression: Re-staging is often performed if cancer comes back (recurs) or progresses (grows or spreads without ever having gone away completely). It helps identify the extent of the recurrence or progression, which is crucial for planning appropriate treatment strategies.

Evaluating eligibility for alternative therapies: In some cases, restaging may reveal that a patient’s cancer has been down-staged, making them eligible for different treatment options, such as surgery or secondary/tertiary chemotherapies.

Assessing the risk of relapse or metastasis: Restaging can provide valuable information about a patient’s prognosis, including the likelihood of the cancer coming back or spreading after the initial treatment. This knowledge helps doctors and patients make informed decisions about follow-up care and surveillance.

Updating staging systems: As doctors learn more about cancer and its behavior, staging systems may be updated to incorporate new findings and improve accuracy. Restaging can help validate and refine these staging systems, making them more valuable for both doctors and patients.

How does re staging affect cancer treatment options?

Restaging cancer can have a significant impact on treatment options, as it provides updated information about the extent of the disease and its response to previous treatments.

Treatment modification: Restaging may lead to changes in the treatment plan, such as switching to a more aggressive therapy if the cancer has progressed or considering less intensive treatments if the cancer has regressed.

Eligibility for alternative therapies: Restaging can help determine if a patient is eligible for additional treatment options, such as surgery, radiation therapy, targeted drug therapy, immunotherapy, or participation in clinical trials.

Prognostic information: Updated staging information can provide valuable insights into a patient’s prognosis, helping doctors and patients make informed decisions about follow-up care and surveillance.

Monitoring treatment response: Restaging is essential for evaluating the effectiveness of the current treatment and guiding decisions about further treatment options.

Clinical trial participation: Restaging may identify patients who are suitable for specific clinical trials, which can offer access to innovative treatments and contribute to the advancement of cancer research.

Communication and collaboration: Restaging helps ensure that the entire healthcare team is on the same page regarding the patient’s diagnosis, treatment, and prognosis, facilitating effective communication and collaboration.

If you have more pressing questions or concerns about cancer, please talk to your doctor.

Continue reading: Cancer: How to navigate the deadly disease