ColorectalCancer (CRC) Pre and Pos Chemotherapy
Male, 46 year old, presented with rectal bleeding and constipation. Colonoscopy, depicted a stenosing tumor at 10 to 15 cm from the anal margin. Biopsy poorly differentiated tubular adenocarcinoma with signet ring cells. CT and MRI of the abdomen and pelvis: wall thickening of recto-sigmoid, associated with a higher density in the adjacent fat planes, without retroperitoneal lymphadenopathy, or lung or liver metastases, but with peritoneal implants. PET-CT, 2 pictures at left show a supra and retro vesical mass and peritoneal nodules. Underwent chemo (oxaliplatino, xeloda and folfox) and radiation therapy. At right followup PET-CT after 2 months treatment, shows a significant tumor decrease (SUV pre, 18 and pos 6) and no peritoneal nodes. Surgery was indicated.
According to Culverwell et al. in review, "(18)Fluorine 2-fluoro-2-deoxy-D: -glucose positron emission tomography-computed tomography (PET-CT) has a firmly established role in staging, restaging, and recurrence detection of a range of tumors" (3). On the other hand Ozkan et al after assessing 69 patients, concludes that "FDG PET/CT is a safe imaging method that can be used in the determination of CRC recurrence in patients with elevated CEA levels, regardless of the CEA level" (4).
References:
1 Simo M. Utilidad de la Tomografia PET en cancer de mama, p: 535-541 and Setoain X. PET en los linfomas, p: 543-547. En Medicina Nuclear Aplicaciones Clínicas. Eds: I. Carrio - P. González. Editorial Masson, Barcelona España, 2003.
2 Rohren EM, Turkington TG, Coleman RE. Clinical applications of PET in oncology. Radiology. 2004 May; 231(2): 305-32.
3
Culverwell AD, Chowdhury FU, Scarsbrook AF. Optimizing the role of FDG PET-CT
for potentially operable metastatic colorectal
cancer.Abdom Imaging. 2012 Feb 28.
4 Ozkan
E, Soydal C, Araz M, Kir KM, Ibis E. The role of 18F-FDG PET/CT in detecting
colorectal cancer recurrence in patients
with elevated CEA levels. Nucl Med Commun. 2012 Apr;33(4):395-402.