Comparison of CT and PET-CT based planning of radiation therapy in locally advanced pancreatic carcinoma

J Exp Clin Cancer Res. 2008 Sep 23;27(1):41. doi: 10.1186/1756-9966-27-41.


Background: To compare computed tomography (CT) with co-registered positron emission tomography-computed tomography (PET-CT) as the basis for delineating gross tumor volume (GTV) in unresectable, locally advanced pancreatic carcinoma (LAPC).

Methods: Fourteen patients with unresectable LAPC had both CT and PET images acquired. For each patient, two three-dimensional conformal plans were made using the CT and PET-CT fusion data sets. We analyzed differences in treatment plans and doses of radiation to primary tumors and critical organs.

Results: Changes in GTV delineation were necessary in 5 patients based on PET-CT information. In these patients, the average increase in GTV was 29.7%, due to the incorporation of additional lymph node metastases and extension of the primary tumor beyond that defined by CT. For all patients, the GTVCT versus GTVPET-CT was 92.5 +/- 32.3 cm3 versus 104.5 +/- 32.6 cm3 (p = 0.009). Toxicity analysis revealed no clinically significant differences between two plans with regard to doses to critical organs.

Conclusion: Co-registration of PET and CT information in unresectable LAPC may improve the delineation of GTV and theoretically reduce the likelihood of geographic misses.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Carcinoma / diagnostic imaging
  • Carcinoma / radiotherapy*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Pancreatic Neoplasms / diagnostic imaging
  • Pancreatic Neoplasms / radiotherapy*
  • Positron-Emission Tomography / methods*
  • Radiotherapy, Conformal
  • Tomography, X-Ray Computed / methods*