The expanding role of PET technology in the management of patients with colorectal cancer

Abstract

The therapeutic options and subsequent survival of colorectal cancer (CRC) patients has increased substantially over recent years. While surgical excision of the primary cancer results in cure of approximately 50% of patients, recurrence and metastatic disease still remains a significant cause of death. Although resection of liver or lung metastases can result in cure, relapse rates remain high, indicating that patient selection needs improvement. Positron emission tomography (PET) technology has a great deal to offer with respect to CRC management, particularly in the setting of patient selection for metastasectomy and in the evaluation of possible recurrent disease, however it has not yet become a routine part of the management of all CRC patients. This review article aims to discuss the current and future implications of PET technology in the optimal management of CRC patients throughout their care pathway.

Diagnostics of intrapulmonary metastases from colorectal cancer (literature survey)

“…PET/CT -Positron-emission tomography (PET) is a radionuclide method, which is used for non-invasive finding and quantitative determination of cellular and biochemical processes (46). This is a method for functional imaging, which could be combined with CT or MRI and by this way to improve the diagnostics of malignant diseases based on the pathologic changes in the tissues (47).…”

“…This is a method for functional imaging, which could be combined with CT or MRI and by this way to improve the diagnostics of malignant diseases based on the pathologic changes in the tissues (47). PET/CT is with a high sensitivity and specificity in diagnosis and treatment of the colorectal cancer in comparison with other diagnostic methods and it is expected in near future it would play main role in this area (1,31,46,47).…”

“…The semi-quantitative analysis of FDG-PET images is performed by calculation of the value of the standard uptake value (SUV). Falsely positive results could be obtained in existing chronic inflammation and after operation or radiotherapy, due to secondary increased uptake of FDG in neutrophils, granulation tissue and macrophages (46). Commonly accepted is the role of FDG-PET in the assessment of the therapeutic effect after radiotherapy, chemotherapy and after usage of ablative technics (46,51).…”

“…Falsely positive results could be obtained in existing chronic inflammation and after operation or radiotherapy, due to secondary increased uptake of FDG in neutrophils, granulation tissue and macrophages (46). Commonly accepted is the role of FDG-PET in the assessment of the therapeutic effect after radiotherapy, chemotherapy and after usage of ablative technics (46,51). The examination could be performed 4 weeks after termination of chemotherapy, one month after operation and 3 months after radiation, because of the possibility for incorrect positive results in inflammatory or regenerative processes.…”

Review article liver metastases

“…However, 18 F-FDG also accumulates in normal liver tissue, resulting in high background, which limits the detection of hypermetabolic liver metastases. FDG-PET is a valuable tool in the detection of hepatic metastases (25,26). Especially in patients with equivocal CT and MR findings and for detection of tumor recurrence FDG-PET has been helpful (27).…”