Radiation Oncology/Vagina/Overview

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Vaginal Cancer Overview


Epidemiology[edit]

  • Majority of vaginal neoplasms are metastatic; typically by direct extension (vulva/cervix), lymphatics, or hematogenous spread.
  • According to FIGO staging, if the tumor involves vulva or the cervical os, it is classified as arising from that structure, even if it is centered in vagina
  • Only 10-20% are primary vaginal tumors, and account for ~2% of gynecologic malignancies
  • Age:
    • 75% in patients >50
    • 60% in patients >70
  • Location PMID 5162136 (1971):
    • 58% tumors occur on posterior wall
    • 51% tumors occur in upper 1/3 of vagina
  • Approximately 60% have had prior hysterectomy for variety of reasons


Anatomy[edit]

Vaginal Anatomy

  • Introitus - vaginal opening
  • Hymen - thin tissue membrane concealing vaginal canal. Formed by connection of the urogenital sinus epithelium invaginating inward, with the mullerian ducts descending from above
  • Fornices - invaginations between walls of vagina and cervix
  • Pouch of Douglas - retrouterine pouch separating vagina from rectum
  • Average length 7.5 cm
  • Vaginal wall
    • Stratified squamous epithelium
    • Muscularis layer
    • Adventitia

Lymphatic drainage of vagina

  • Complex
  • Upper 2/3 of vagina - pelvic nodes (obturator, internal/external iliac)
  • Lower 1/3 of vagina - inguinal and pelvic nodes
  • 5-20% present with clinically positive nodes


  • Torino, Italy; 2002 PMID 12210022 -- "Rationale and definition of the lateral extension of the inguinal lymphadenectomy for vulvar cancer derived from an embryological and anatomical study." (Micheletti L, J Surg Oncol. 2002 Sep;81(1):19-24.)
    • Embryological and anatomic study to determine lateral extension of groin lymphadenectomy in vulvar cancer. 3 human fetuses, 1 patient dissected
    • Outcome: Most lateral superficial inguinal lymph node does not rise above medial margin of the sartorius muscle, nor far lateral to where superficial circumflex iliac vessels cross the inguinal ligament
    • Conclusion: Lateral surgical landmark established

Risk Factors[edit]

  • Approximately 2/3 are HPV-related
  • HSV, trichomonas, number of sexual partners >5
  • Long term pessary use, smoking, immunosuppression, pelvic radiation
  • Maternal use of diethylstilbestrol (DES) during first 4 months in utero

Associated with prior cervical carcinoma[edit]

  • U. Michigan, 1982 - PMID 7095583 (No abstract) PDF -- "Neoplasms of the vagina following cervical carcinoma." (Choo YC, Gynecol Oncol. 1982 Aug;14(1):125-32.)


Prevention & Screening[edit]

  • Insufficient evidence for women s/p TAH
  • Pap smear for high-risk populations; continue into older years


Presentation[edit]

  • Abnormal vaginal bleeding in 50-75%, discharge, pruritus
  • Dysuria, pelvic pain in more advanced disease


Work-Up[edit]

  • Speculum examination, rotate to observe posterior wall
  • Vaginal palpation, bimanual pelvic, rectovaginal for staging
  • Evaluate vulva and cervical os for disease - biopsy suspicious lesions
  • Evaluate for mets with CXR, CBC, LFTs and alk phos
  • Biopsy suspicious inginal nodes
  • Stage II or greater consider cystoscopy and/or sigmoidoscopy
  • Consider MRI - superior to CT for evaluation of soft tissue extension (though neither may be used in clinical staging)
    • Consider dynamic contrast MRI


  • Manchester; 2007 (UK)(1996-2005) PMID 17467392 -- "Magnetic resonance imaging of primary vaginal carcinoma." (Taylor MB, Clin Radiol. 2007 Jun;62(6):549-55.)
    • Retrospective. 25 patients with MRI examination. Isointense to muscle on T1, hyperintense on T2
    • Outcome: 88% extension beyond vagina, 56% Stage III/IV
    • Conclusion: MRI identified >95% tumors, radiological staging correlated with outcome, and provided treatment planning information


Histology[edit]

  • Squamous cell carcinoma (80-90%), primarily in older patients, invade locally with mets to lung and liver
  • Melanoma (3-5%), second most common cancer in vagina
  • Clear cell carcinoma, particularly in young women with DES exposure in utero (FDA advised against DES use in 1971 - thus incidence has dropped dramatically)
  • Rhabdomyosarcoma (botryoid type) most common in children
  • Verrucous carcinoma (rare) - tend to recur locally and rarely metastasize thus surgical approaches may be appropriate PMID 635607


Prognostic Factors[edit]

  • Clinical stage most important
  • Adenocarcinoma and non-epithelial tumors (melanoma, sarcoma) worse than squamous cell