Goblet Cell Carcinoma (GCC)

Goblet cell carcinomas (GCC) are rare neuroendocrine tumours that develop in the appendix. More specifically, they develop in goblet cells, which are responsible for mucus secretion and production. The mucus acts as a protective layer in the intestines.

Neuroendocrine cancers are a complex group of tumours that develop in the neuroendocrine system, which is responsible for regulating important bodily functions such as heart rate, blood pressure and metabolism. They most commonly develop in the gastro-intestinal tract, pancreas, and the lungs; however, they can develop anywhere in the body. These tumours develop from neuroendocrine cells, which are responsible for receiving signals from the nervous system and producing hormones and peptides (small proteins) in response.

GCCs demonstrate a unique combination of both neuroendocrine cells and adenocarcinoma cells, which are cancerous cells that develop from mucus-producing cells. They tend to be more aggressive than classic neuroendocrine tumours, but are classified and staged as carcinomas of the appendix.

This type of cancer is diagnosed equally in males and females, and is generally diagnosed in people between the ages of 50-60. However, anyone can develop this disease.

Treatment

If a GCC is detected, it will be staged and graded based on size, metastasis, and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you.

Cancers can be staged using the TNM staging system:

  • T (tumour) indicates the size and depth of the tumour.
  • N (node) indicates whether the cancer has spread to nearby lymph nodes.
  • M (metastasis) indicates whether the cancer has spread to other parts of the body.

This system can also be used in combination with a numerical value, from stage 0-IV:

  • Stage 0: this stage describes cancer cells in the place of origin (or ‘in situ’) that have not spread to nearby tissue.
  • Stage I: cancer cells have begun to spread to nearby tissue. It is not deeply embedded into nearby tissue and had not spread to lymph nodes. This stage is also known as early-stage cancer.
  • Stage II: cancer cells have grown deeper into nearby tissue. Lymph nodes may or may not be affected. This is also known as localised cancer.
  • Stage III: the cancer has become larger and has grown deeper into nearby tissue. Lymph nodes are generally affected at this stage. This is also known as localised cancer.
  • Stage IV: the cancer has spread to other tissues and organs in the body. This is also known as advanced or metastatic cancer.

Cancers can also be graded based on the rate of growth and how likely they are to spread:

  • Grade I: cancer cells present as slightly abnormal and are usually slow growing. This is also known as a low-grade tumour.
  • Grade II: cancer cells present as abnormal and grow faster than grade-I tumours. This is also known as an intermediate-grade tumour.
  • Grade III: cancer cells present as very abnormal and grow quickly. This is also known as a high-grade tumour.

Once your tumour has been staged and graded, your doctor may recommend genetic testing, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.

Treatment is dependent on several factors, including location, stage of disease and overall health.

Treatment options for GCCs may include:

  • Surgery, potentially including:
    • Appendectomy.
    • Right hemicolectomy.
  • Radiation therapy.
  • Chemotherapy.
  • Targeted therapy.
  • Clinical trials.
  • Palliative care.

Risk factors

Because of how rare GCCs are, there has been limited research done into the risk factors for this disease. However, some studies have indicated that schistosomiasis (tropical parasite) may have a link to GCC.

Symptoms

People who have GCC may experience some of the following symptoms:

  • Appendicitis.
  • Abdominal pain/distention (swelling).
  • Bowel obstruction.
  • Abdominal lump.
  • Gastrointestinal bleeding.
  • Intussusception.

Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.

Diagnosis

In many cases, GCCs are diagnosed during an appendectomy to treat an appendicitis. If your doctor suspects you have a GCC, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

  • Physical examination.
  • Imaging tests, potentially including:
    • MRI (magnetic resonance imaging).
    • CT (computed tomography) scan.
  • Blood tests.
  • Biopsy.

References

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