VAIN
is a rare disease with an incidence of 0.2 to 0.3 per 100,000 women (1). Risk
factors include smoking, low social economic status, history of abnormal Papanicolaou smear, genital warts and early hysterectomy
(2, 3). A history of cervical dysplasia and cancer is seen in 48% and 9%
respectively (3). VAIN may regress or progress to higher grade VAIN and
invasive cancer. Among those with no treatment, 87% normalized, 9% persisted
and 4% recurred (3). Progression of high grade VAIN to invasive cancer is 8%
(4).
The
majority (94%) of VAIN patients are asymptomatic (1). Around 76% of cases
present with abnormal cytology while 22% present with vaginal warts (5).
Diagnosis is by colposcopy directed vaginal biopsy. Acetowhite
epithelium, absence of iodine uptake, punctuation and mosaicism
is seen in 84%, 81%, 14% and 2% respectively (1, 5). The upper third of vagina
is involved in 92.4% and is the most commonly affected site (6).
Treatment
options of VAIN include conservative, medical (imiquimod
cream, 5-fluorouracil cream, tricholoroacetic acid)
(7, 8), surgical treatment (laser ablation, excision, vaginectomy)
(8) and brachytherapy (9, 10). The choice of treatment is influenced by age,
comorbidities, number and location of lesions, length of vagina, sexual
activity, previous treatment, previous radiotherapy, physician experience and
patient preference (1).
Conservative
treatment and imiquimod cream are mostly for low
grade VAIN and
is not the treatment of choice for our patient (4, 7). Intravaginal 50% tricholoroacetic
acid is successful in 53% of VAIN II/III (11). 5-fluorouracil cream is curative
in 46% of VAIN II/III (4). However, it has side effects with 77.8% having vaginal
discharge, 44.4% having post-coital bleeding, 8.2% having epithelial ulcers and
5.6% experiencing pain (12).
The
success rate of surgical methods in treating VAIN II/III is higher. Laser
ablation cures 68% of cases (13). It has the advantage of having minimal blood
loss, suitable for multifocal lesions and sexual function can be retained.
However, it is not desirable for VAIN at the vaginal vault because VAIN can be
buried by suture lines and may not be adequately assessed by cytology or
colposcopy (8). No histology can be obtained and invasive cancer may be missed.
VAIN III in vaginal vault treated with laser ablation is associated with higher
risk of recurrence (14). Vaginectomy can provide
surgical specimen to assess possibility of invasive cancer and resection
margins (1). The cure rate of upper vaginectomy for
VAIN II/III is 80% (13). It is associated with risk of bladder or rectal
injury, loss of coital function, vesicovaginal
fistula and rectovaginal fistula. Upper vaginectomy is more successful than laser treatment in hysterectomized group (46% versus 20% success rate) (13).
Brachytherapy
can be considered in highly selected patients such as poor surgical candidate
with extensive VAIN. A local control rate of 93% has been reported (10).
Single
treatment results in regression in 70%, 24% recur and 5% progress to invasion
(15). Recurrence following partial vaginectomy, laser
ablation and 5-fluorouracil was 0%, 38% and 59% respectively (1). Another study
found a recurrence rate of 17% after vaginectomy for
VAIN III (16). Recurrence rate of multifocal disease is higher than unifocal disease (57% versus 43%) (13). Grade of VAIN does
not affect recurrence (1, 3, 15).
Our patient had two
recurrences. Two recurrences are only seen in 8% of cases (1).
The first episode of VAIN was diagnosed with cervical cancer and can be treated
concomitantly with surgery. The extent of VAIN can be marked pre-operatively
and vagina can be resected beyond the VAIN lesion. The recurrences were at the
vaginal vault therefore laser ablation is not a desirable treatment. Medical
therapy has lower success rate compared to vaginectomy.
VAIN occurring after radiation therapy has been shown to be more refractory
than those without history of radiation therapy and may be more likely to
progress to invasive cancer (17). Vaginectomy can
allow histological examination with higher success rate and is the appropriate
treatment. Brachytherapy is an option but is associated with radiation
exposure, secondary malignancy, affects sexual function and future surgery.
VAIN
patients should be followed up with colposcopy and cytology (3). There is no
evidence to support optimal interval and duration of follow up. Some suggested
annual follow up (3). Late progression to invasive cancer has been reported (4,
9) and therefore VAIN cases should be followed up indefinitely (3).
