Cervical Neuroendocrine Tumours

Cervical neuroendocrine tumours (NETs), also known as cervical carcinoid tumours, are a very rare form of neuroendocrine tumour that develops from the cervix, a part of the female reproductive system that connects the uterus to the vagina. It has many important functions, including fluid production for vaginal health, mucus production to assist sperm in the fertilisation process, and it acts as a barrier to hold the baby in the uterus until birth.

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.

Cervical NETs are most commonly diagnosed around the age of 40, however it can affect anyone with a cervix – including pre-menopausal women, teenagers, transgender men, non-binary individuals, and intersex people – at any age.

Types of Cervical Neuroendocrine Tumours

Because of how rare cervical NETs are, there has been limited research done into the types of this disease. However, some variants of this disease have been identiftied.

Neuroendocrine Carcinomas of the Cervix

Neuroendocrine carcinomas of the cervixare a rare type of cancer that are characterised by abnormal looking cancer cells under the microscope. There are two primary subtypes of this disease.

Small Cell Carcinoma of the Cervix

Small cell neuroendocrine carcinoma of the cervix (SCNECC), also known as oat cell neuroendocrine carcinoma of the cervix, is the most common variant of cervical NETs; however, they represent a very small proportion of cervical cancers. This type of tumour is often classified as a type of extrapulmonary small cell lung cancer, as the cells present are identical under a microscope. Unfortunately, SCNECC is often aggressive and may not have as good of a prognosis as other types of cervical cancers.

Large Cell Carcinoma of the Cervix

Large cell carcinomas of the cervix are a very rare form of cancer that is often associated with large cell undifferentiated carcinoma of the lungs. Unfortunately, large cell carcinomas of the cervix are often aggressive, and may not have as good of a prognosis as other types of cervical cancers.

Typical Carcinoid Tumour of the Cervix

Typical carcinoid tumours of the cervix are a less common type of cervical NET that are generally classified as grade one (slow growing) neuroendocrine tumours. These tumours are less common than atypical carcinoid tumours of the cervix, and can have a good prognosis when caught early.

Atypical Carcinoid Tumour of the Cervix

Atypical carcinoid tumours of the cervix are a more common type of cervical NET that are generally more aggressive than typical carcinoid tumours of the cervix. This subtype is more likely to metastasise, and may not have as good of a prognosis as other types of cervical cancers.

Treatment

If a cervical NET 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.

FIGO Staging System

Gynaecological cancers, such as cervical NETs, can be staged using the Federation of Gynaecology and Obstetrics (FIGO) system from stage I to IV:

  • Stage I: cancer cells are confined to cervix tissue only. This stage is also known as early-stage cancer.
  • Stage II: cancer cells have spread to the upper two-thirds of the vagina and/or other nearby tissue. This is also known as localised cancer.
  • Stage III: the cancer has become larger and has spread to lower third of the vagina and/or the side of the pelvic wall. Lymph nodes and kidneys may be affected. This is also known as advanced or metastatic cancer.
  • Stage IV: the cancer has spread to the bladder or rectum, or to more distant organs, such as the lungs or the liver. This is also known as advanced or metastatic cancer.

TNM Staging System

The TNM system can also be used to classify a cervical NET. The TNM system is comprised of:

  • 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 Options

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

Treatment options for cervical NETs may include:

  • Surgery, potentially including:
    • Cone biopsy.
    • Trachelectomy.
    • Hysterectomy.
    • Unilateral salpingo-oophorectomy.
    • Bilateral salpingo-oophorectomy.
    • Anterior pelvic exenteration.
    • Posterior pelvic exenteration.
    • Total pelvic exenteration.
    • Lymphadenectomy.
  • Somatostatin analogues (SSAs).
  • Chemotherapy.
  • Targeted therapy.
  • Radiation therapy, potentially including brachytherapy.
  • Clinical trials.
  • Palliative care.

Cervical Neuroendocrine Tumour Treatment and Fertility

Treatment for cervical NETs may make it difficult to become pregnant. If fertility is important to you, discuss your options with your doctor prior to the commencement of treatment.

Risk factors

Because of how rare cervical NETs are, there has been little research done into the risk factors of this disease. However, there may be a potential link to the development of this disease and infection with the human papillomavirus (HPV), which is a sexually transmitted disease (STD).

Symptoms

Some patients with cervical NETs will appear asymptomatic in the early stages of disease. As the tumour progresses, some of the following symptoms may appear:

  • Changes in menstrual periods, such as irregular periods, unusual vaginal bleeding, or vaginal bleeding post menopause.
  • Abnormal vaginal discharge.
  • Pelvic pain and/or pressure.
  • Pain during intercourse.
  • Bleeding after intercourse.
  • Urinary changes, such as changes in frequency, urgency and/or incontinence.
  • Unexplained weight loss.
  • Fatigue.
  • Abdominal pain/discomfort/pressure.
  • Carcinoid syndrome (rare), which carries its own set of symptoms:
    • Facial flushing (usually red or purple in the face, neck, and/or upper chest).
    • Diarrhoea.
    • Wheezing.
    • Abdominal pain.
    • Carcinoid heart disease (plaques on the heart muscle caused by excess hormone production).
    • Faecal urgency.
    • Fatigue.
    • Skin changes, such as red or purple spots on the face, neck, and/or upper chest.
  • Paraneoplastic syndromes (rare).
  • Hypercalcaemia (rare).

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

Diagnosis

If your doctor suspects you have a cervical NET, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

  • Physical examination.
  • Pelvic examination.
  • Cervical screening test.
  • Imaging tests, potentially including:
    • Pelvic ultrasound.
    • Transvaginal ultrasound.
    • MRI (magnetic resonance imaging).
    • CT (computed tomography) scan.
    • PET (positron emission tomography) scan.
  • Blood tests.
  • Exploratory surgery.
  • Biopsy.

References

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