Obstetrics and Gynecology/Cervical Neoplasia

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Epidemiology[edit | edit source]

  • Approximately 1/10000 women will develop cervical cancer.
  • Cervical cancer accounts for 1.1% of all cancer deaths in women.
  • Cervical cancer is diagnosed around ages 37 and 62, with a mean age of 52.

Etiology, Pathophysiology, and Risk Factors[edit | edit source]

Squamocolumnar metaplasia is the basis for malignant transformation. However, this transformation is a normal process that begins at puberty and accelerates during pregnancy. Metaplastic cells are particularly vulnerable to HPV infection.

HPV infection breeds dysplasia, a process that occurs in only 1-3% of women infected with HPV, and finally progresses to invasive carcinoma.

    • Note that >80% of sexually active women have been infected with HPV. However, the majority of these infections resolve spontaneously.

Clinical Presentation and Diagnostic Approach[edit | edit source]

Cervical cancers typically present as

  • An abnormal pap smear
  • Abnormal bleeding
  • Vaginal discharge, usually purulent
  • Pain (a late symptom of advanced cervical cancer)
  • Renal failure (a late symptom of advanced cervical cancer from bilateral ureteric obstruction

Screening Guidelines for Cervical Cancer[edit | edit source]

The following guidelines are a summary of the screening guidelines for cervical cancer in Alberta, Canada.

  • Screening should start at age 21 or 3 years after sexual debut, whichever occurs later.
  • Perform yearly pap smears until 3 consecutive negative results, then move to every 3 years, unless woman is immunocompromised or past history of cancer/precancer.
  • If at age 69 there have been no abnormalities, pap smears may cease.

Referral guidelines for cervical cancer screening results

  • Continue routine screening if normal
  • Repeat pap earlier: ASCUS/LSIL
  • Refer for colposcopy: ASC-H/HSIL/Atypical Glandular Cells (AGC)/Adenocarcinoma in situ
  • Refer to gynecological oncologist: invasive cancer

Pathology, Histology, and Staging[edit | edit source]

Histologically, cervical cancer is split into three categories:

  • Squamous cell: (80% of cervical cancers)
    • These arise from the squamous epithelium in the transition zone of the cervix.
  • Adenocarcinoma: (~20% of cervical cancers)
    • These arise from the columnar cells in the cervical canal.
  • Other: small cell neuroendocrine, Glassy cell carcinoma, Clear cell carcinoma, adenoma malignum

Cervical cancer spreads either

  • Directly: typically along the parametrium, via the cardinal ligaments.
  • Lymphatically: obtruator->internal iliac->common iliac->para-aortic

Staging[edit | edit source]

The staging of cervical cancer and the respective treatment options are presented in the table below.

Stage Classification Treatment 5 yr Survival
IA1 Lesion less than 3mm deep, confined to cervix Cone excision or radical hysterectomy 100%
IA2 Lesion between 3 and 5 mm deep, confined to cervix Cone excision or radical hysterectomy, plus nodal dissection 100%
IB1 Lesion greater than 5mm but less than 4cm, confined to cervix Radical hysterectomy, nodes, radiotherapy +/- chemotherapy 85-90%
IB2 Lesion greater than 4cm but confined to cervix Radiotherapy +/- chemotherapy 85-90%
IIA Upper vagina with no parametrial involvement Radiotherapy +/- chemotherapy, some will get surgery 50-75%
IIB Parametrial involvement Radiotherapy +/- chemotherapy 50-75%
IIIA Lower third of the vagina with no sidewall involvement Radiotherapy +/- chemotherapy 30-50%
IIIB Invasion of the pelvic wall and/or causes hydronephrosis Radiotherapy +/- chemotherapy 30-50%
IVA Invasion of the bowel or bladder, but no extension past the true pelvis Palliative radiotherapy +/- chemotherapy 10%
IVB Distant metastases Palliative radiotherapy +/- chemotherapy 10%

Treatment decisions will be influenced by fitness and desire to have children.

Management[edit | edit source]

See Staging table for management strategies.

If, at colposcopy, transitional zone lesions are found, the entire transition zone must be excised via loop electrosurgical excision procedure (LEEP). If colposcopy was unsatisfactory (i.e. unable to visualize entire lesion or adenocarcinoma in situ diagnosed), cone biopsy must be performed.

  • Cone biopsy may result in cervical stenosis or incompetence.

If vaginal precancer is diagnosed at colposcopy, laser therapy can be administered.

Side effects for radiation are: Early: cystitis, diarrhea, pubic hair loss Late: radiation cystitis/proctitis, small bowel obstruction, vaginal stenosis, ovarian failure, and rarely fistula formation

For recurrent disease, surgery is the only option, with pelvic exenteration providing cure rates of 50-60%.