The Application of Classification and Regression Trees for the Triage of Women for Referral to Colposcopy and the Estimation of Risk for Cervical Intraepithelial Neoplasia: A Study Based on 1625 Cases with Incomplete Data from Molecular Tests.
OBJECTIVE
Nowadays numerous ancillary techniques detecting HPV DNA and mRNA compete with cytology; however no perfect test exists; in this study we evaluated classification and regression trees (CARTs) for the production of triage rules and estimate the risk for cervical intraepithelial neoplasia (CIN) in cases with ASCUS+ in cytology.


METHODS
We used 1625 cases. In contrast to other approaches we used missing data to increase the data volume, obtain more accurate results, and simulate real conditions in the everyday practice of gynecologic clinics and laboratories. The proposed CART was based on the cytological result, HPV DNA typing, HPV mRNA detection based on NASBA and flow cytometry, p16 immunocytochemical expression, and finally age and parous status.


RESULTS
Algorithms useful for the triage of women were produced; gynecologists could apply these in conjunction with available examination results and conclude to an estimation of the risk for a woman to harbor CIN expressed as a probability.


CONCLUSIONS
The most important test was the cytological examination; however the CART handled cases with inadequate cytological outcome and increased the diagnostic accuracy by exploiting the results of ancillary techniques even if there were inadequate missing data. The CART performance was better than any other single test involved in this study.
Department of Cytopathology, University of Athens Medical School, Attikon University Hospital, Rimini 1, Haidari, 12462 Athens, Greece.
Abraham
A
Pouliakis
Biomedical Engineering Laboratory, National Technical University of Athens, Iroon Politechniou 9, Zografou, 15780 Athens, Greece.
Efrossyni
E
Karakitsou
3rd Department of Obstetrics and Gynecology, University of Athens Medical School, Attikon University Hospital, Rimini 1, Haidari, 12462 Athens, Greece.
Charalampos
C
Chrelias
3rd Department of Obstetrics and Gynecology, University of Athens Medical School, Attikon University Hospital, Rimini 1, Haidari, 12462 Athens, Greece.
Asimakis
A
Pappas
2nd Department of Pathology, University of Athens Medical School, Attikon University Hospital, Rimini 1, Haidari, 12462 Athens, Greece.
Ioannis
I
Panayiotides
Department of Obstetrics & Gynecology, University Hospital of Ioannina, Stavros Niarchos Avenue, 45500 Ioannina, Greece ; Department of Obstetrics & Gynaecology, Worthing Hospital, Western Sussex Hospitals NHS Foundation Trust, Worthing BN11 2DH, UK.
George
G
Valasoulis
Department of Surgery and Cancer, Institute of Reproductive & Developmental Biology, Faculty of Medicine, Imperial College, London W12 0NN, UK ; West London Gynaecological Cancer Center, Queen Charlotte's and Chelsea-Hammersmith Hospital, Imperial Healthcare NHS Trust, London W12 0HS, UK.
Maria
M
Kyrgiou
Department of Obstetrics & Gynecology, University Hospital of Ioannina, Stavros Niarchos Avenue, 45500 Ioannina, Greece.
Evangelos
E
Paraskevaidis
Department of Cytopathology, University of Athens Medical School, Attikon University Hospital, Rimini 1, Haidari, 12462 Athens, Greece.
Petros
P
Karakitsos
D000328:Adult; D000368:Aged; D003127:Colposcopy; D003581:Cytodiagnosis; D004279:DNA, Viral / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D006801:Humans; D008875:Middle Aged; D027383:Papillomaviridae / Q000145:classification / Q000302:isolation & purification* / Q000472:pathogenicity; D011247:Pregnancy; D012307:Risk Factors; D014218:Triage; D002578:Uterine Cervical Dysplasia / Q000235:genetics / Q000473:pathology* / Q000821:virology / Q000145:classification; D014626:Vaginal Smears
D004279:DNA, Viral