RANDOMISED INTERVENTION TRIAL TO EVALUATE SINGLE- AND DOUBLE- FREEZE CRYOTHERAPY IN THE PREVENTION OF CERVICAL NEOPLASIA
Healthy women aged 25 to 64 yrs with histology confirmed ectocervical CIN lesions confined
to ectocervix without extension to endocervix or vagina will be randomized to single- or
double-freeze cryotherapy, as per the inclusion criteria will be invited to participate in
They will be explained about the study. Informed consent will be obtained from each
recruited woman. The cases selected with lesions that can be adequately covered with largest
cryo probe (2.5 cm diameter) will be randomized between the following arms.
Arm 1 Single-freeze technique; 3 minutes of freeze and 5 minutes of thaw. Arm 2
Double-freeze technique: 3 minutes of freeze and 5 minutes of thaw and cycle repeated once
The patients will be advised about excessive discharge per vagina for 4 weeks and mild
They will be advised to abstain from sexual intercourse for 6 weeks. They would be followed
up after one month for clinical evaluation and at 12th month to determine the cure rates by
Pap test, HPV Test and colposcopy with or without biopsy.
The reference investigations to determine cure rates at the end of 12 months would be Pap
smear, HPV Testing by HC II and colposcopy with or with out biopsy which will be offered to
all the participants and biopsy will be done on women with colposcopic abnormalities.
Randomized trial: Stratified by lesion. Randomisation and analysis will be stratified on the
grades of CIN.
Each woman eligible for cryotherapy who presents for treatment, will be allocated a
This randomisation number is a 4 digit number: The first digit represent the CIN stage (1, 2
or 3), the 3 next digits are the sequential number of the patient (from 001 to 999). Each
sequential number is randomly attributed to a treatment arm. The table containing this
information will be kept by the principal investigator and is only known by the people
involved in the treatment.
The arm the patient has been randomised to will not be known by the people performing the
follow-up visit in order to avoid any reporting bias. As soon as the patient has been
randomised to double- or single-freeze, the box corresponding to the sequential number line
and the CIN column will be marked with 'X'. The randomisation protocol will be rigorously
Women with biopsy proven ASCUS-H and CIN lesion, after obtaining an informed consent will be
randomized between single and double freeze treatment cases. The first follow-up is after
one month and the next at 12th month, where patient would be subjected to Pap test, HPV Test
by Hybrid Capture II and colposcopy with or without biopsy.
Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention
The primary end point is the cure rate at the end of one year
Gauravi A MIshra, MD
Tata Memorial Hospital
India:Tata Memorial Hospital