La radiologia medica

, Volume 115, Issue 8, pp 1267–1278

CT colonography before colonoscopy in subjects with positive faecal occult blood test. Preliminary experience

  • L. Sali
  • M. Falchini
  • P. Della Monica
  • D. Regge
  • A. G. Bonanomi
  • G. Castiglione
  • G. Grazzini
  • M. Zappa
  • F. Mungai
  • C. Volpe
  • M. Mascalchi
Abdominal Radiology / Radiologia Addominale

Abstract

Purpose

We report a preliminary evaluation of the performance of computed tomography colonography (CTC) systematically obtained before optical colonoscopy (OC) in subjects with positive faecal occult blood test (FOBT) within a population-based screening programme for colorectal cancer (CRC).

Materials and methods

Seventy-nine subjects with positive FOBT from a regional screening programme were invited to perform same day CTC and OC. CTC was performed with standard bowel preparation. OC with segmental unblinding was the reference standard. A perpatient per-adenoma analysis was performed.

Results

Forty-nine of 79 subjects (62%) with positive FOBT adhered to the study and completed both examinations. Twenty-two (44.9%) of the 49 had a cancer or an adenoma ≥6 mm. Per-patient sensitivity, specificity, negative predictive value and positive predictive value for cancer or adenoma ≥6 mm were 95.5% (95%CI:77.2%–99.9%), 51.9% (95%CI:32.0%–71.3%), 93.3% (95%CI:68.1%–99.8%) and 61.8% (95%CI:43.6%–77.8%).

Conclusions

In the setting of a FOBT-based screening programme for CRC, CTC showed a high sensitivity, but relatively low specificity and positive predictive value, for cancer and adenoma ≥6 mm. Probably performing CTC without faecal tagging as second line test after a positive FOBT is not a cost-effective strategy.

Keywords

Computed tomography colonography Faecal occult blood test Colorectal cancer screening 

Valutazione della colongrafia TC come test di secondo livello in soggetti con sangue occulto fecale positivo. Esperienza preliminare

Riassunto

Obiettivo

Valutare la performance della colongrafia TC (CTC) eseguita sistematicamente prima della colonscopia ottica (CO) in soggetti con test del sangue occulto fecale (FOBT) positivo nell’ambito di un programma di screening di popolazione per il cancro colorettale.

Materiali e metodi

Settantanove soggetti FOBT positivi del programma di screening della regione Toscana sono stati invitati ad eseguire nello stesso giorno la CTC e la CO dopo preparazione intestinale standard (polietilenglicole). Come standard di riferimento è stata utilizzata la CO effettuata con la tecnica del “segmental unblinding”. Sono stati calcolati i valori di sensibilità, specificità, valore predittivo negativo (VPN) e positivo (VPP) per-paziente per-adenoma.

Risultati

Su 79 soggetti invitati 49 (62%) hanno accettato di partecipare allo studio. Ventidue soggetti (44,9%) su 49 hanno presentato un cancro o un adenoma ≥6 mm. I valori di sensibilità, specificità, VPN e VPP per-paziente nella detezione di cancri o adenomi ≥6 mm sono risultati rispettivamente del 95,5% (95%CI:77,2%‐99,9%), 51,9% (95%CI:32,0%–71,3%), 93,3% (95%CI:68,1%–99,8%) e del 61,8% (95%CI:43,6%–77,8%).

Conclusioni

Nel contesto di un programma di screening basato sul FOBT, la CTC ha mostrato elevata sensibilità ma bassi valori di specificità e valore predittivo positivo. Probabilmente utilizzare la CTC come test di secondo livello nei soggetti FOBT positivi non è una strategia costo-efficace.

Parole chiave

Colongrafia TC Test del sangue occulto fecale Screening del cancro colorettale 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References/Bibliografia

  1. 1.
    Hardcastle JD, Chamberlain JO, Robinson MH et al (1996) Randomised controlled trial of faecal-occult-blood screening for colorectal cancer. Lancet 348:1472–1477CrossRefPubMedGoogle Scholar
  2. 2.
    Arbyn M, Van Oyen H, Lynge E et al (2003) European Commission’s proposal for a council recommendation on cancer screening. BMJ 327:289–290CrossRefPubMedGoogle Scholar
  3. 3.
    Zorzi M, Falcini F, Fedato C et al (2008) Screening for colorectal cancer in Italy: 2006 survey. Epidemiol Prev 32(2 Suppl 1):55–68PubMedGoogle Scholar
  4. 4.
    van Rossum LG, van Rijn AF, Laheij RJ et al (2008) Random comparison of guaiac and immunochemical fecal occult blood tests for colorectal cancer in a screening population. Gastroenterology 135:82–90CrossRefPubMedGoogle Scholar
  5. 5.
    Grazzini G, Castiglione G, Ciabattoni C et al (2004) Colorectal cancer screening programme by faecal occult blood test in Tuscany: first round results. Eur J Cancer Prev 13:19–26CrossRefPubMedGoogle Scholar
  6. 6.
    Chaparro M, Gisbert JP, Del Campo L et al (2009) Accuracy of computed tomographic colonography for the detection of polyps and colorectal tumors: a systematic review and metaanalysis. Digestion 80:1–17CrossRefPubMedGoogle Scholar
  7. 7.
    Johnson CD, Chen MH, Toledano AY et al (2008) Accuracy of CT colonography for detection of large adenomas and cancers. N Engl J Med 359:1207–1217CrossRefPubMedGoogle Scholar
  8. 8.
    Halligan S, Altman DG, Taylor SA et al (2005) CT colonography in the detection of colorectal polyps and cancer: systematic review, metaanalysis, and proposed minimum data set for study level reporting. Radiology 237:893–904CrossRefPubMedGoogle Scholar
  9. 9.
    Mulhall BP, Veerappan GR, Jackson JL (2005)Meta-analysis: computed tomographic colonography. Ann Intern Med 142:635–650PubMedGoogle Scholar
  10. 10.
    Rosman AS, Korsten MA (2007) Metaanalysis comparing CT colonography, air contrast barium enema, and colonoscopy. Am J Med 120:203–210CrossRefPubMedGoogle Scholar
  11. 11.
    Regge D, Laudi C, Galatola G et al (2009) Diagnostic accuracy of computed tomographic colonography for the detection of advanced neoplasia in individuals at increased risk of colorectal cancer. JAMA 301:2453–2461CrossRefPubMedGoogle Scholar
  12. 12.
    Gluecker TM, Johnson CD, Harmsen WS et al (2003) Colorectal cancer screening with CT colonography, colonoscopy, and double-contrast barium enema examination: prospective assessment of patient perceptions and preferences. Radiology 227:378–384CrossRefPubMedGoogle Scholar
  13. 13.
    Gryspeerdt S, Lefere P, Herman M et al (2005) CT colonography with fecal tagging after incomplete colonoscopy. Eur Radiol 15:1192–1202CrossRefPubMedGoogle Scholar
  14. 14.
    Neri E, Vagli P, Turini F et al (2009) Diagnostic accuracy of CT colonography in patients with positive faecal occult blood test: results of the Italian project Legatumori 2003–2006. Radiol Med 114:586–594CrossRefPubMedGoogle Scholar
  15. 15.
    Sali L, Falchini M, Bonanomi AG et al (2008) CT colonography after incomplete colonoscopy in subjects with positive faecal occult blood test. World J Gastroenterol 14:4499–4504CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Italia 2010

Authors and Affiliations

  • L. Sali
    • 1
  • M. Falchini
    • 1
  • P. Della Monica
    • 2
  • D. Regge
    • 2
  • A. G. Bonanomi
    • 3
  • G. Castiglione
    • 3
  • G. Grazzini
    • 3
  • M. Zappa
    • 3
  • F. Mungai
    • 1
  • C. Volpe
    • 1
  • M. Mascalchi
    • 1
  1. 1.Radiodiagnostic Section — Department of Clinical PhysiopathologyUniversity of FlorenceFlorenceItaly
  2. 2.Radiology UnitInstitute for Cancer Research and TreatmentCandiolo, TurinItaly
  3. 3.Cancer Prevention and Research Institute (ISPO)FlorenceItaly

Personalised recommendations