A preliminary investigation of genomic screening in cervical carcinoma by comparative genomic hybridization

Available clinical, radiological and histopathologic risk factors are not adequate for accurate prognosis in uterine cervix carcinoma. Hence there is a need to identify indicators to select high risk cases. Most cancers occur and progress through step-wise somatic genetic mutations. Thus screening of whole genome for specific genomic alterations and its outcome following treatment may predict prognosis. The present study was carried out to investigate genomic alterations associated with cervical carcinoma and any association of genomic alterations with clinico-pathologic parameters.

Cervical carcinoma cases (n = 4) were subjected to protocol based clinical evaluation, treatment and follow up as a double blind procedure. Tumour samples were collected before radiotherapy and 3 months after completion of radiotherapy. All the samples were stored at -80 degrees C. Comparative genomic hybridization (CGH) was carried out to screen genomic alterations in all tumour samples obtained before treatment. Conventional fluorescent in situ hybridization (FISH) was carried out to confirm the CGH findings and to follow up post-treatment samples. Patients were followed up for a minimum of one year or until death.

The CGH analysis identified genomic losses and gains. The gains were observed mainly in chromosomes 1q 25.1, 3q 26.1, 6q 13-16, 9p 22 and X, and losses in chromosome 10 and 11q21-24. CGH and FISH results were complementary to each other. Of the four patients, two were alive and two were dead at the end of follow up.

Initial results indicated that persistence of genomic alterations and appearance of giant nucleus was associated with poor prognosis and the same may be used to follow up patient. Similar studies on large sample with longer period of follow up are warranted to validate our result.