somddd.pdf

Staging of Malignant Disease ▪ Staging of cancer depends on the size of the primary neoplasm, its extent to regional lymph nodes, and the presence or absence of metastasis. ▪ Accurate staging of malignant lesions at the time of initial presentation is of utmost importance to provide appropriate mana...

Staging of Malignant Disease ▪ Staging of cancer depends on the size of the primary neoplasm, its extent to regional lymph nodes, and the presence or absence of metastasis. ▪ Accurate staging of malignant lesions at the time of initial presentation is of utmost importance to provide appropriate management for a particular patient. 12 Staging of Malignant Disease ▪ Overstaging can inappropriately deprive a patient from receiving curative treatment such as surgery. ▪ On the other hand understaging can subject a patient to undergo futile but drastic treatments that can even increase the morbidity and mortality (e.g. pneumonectomy in lung cancer) without any increase in the chance of cure. ▪ Imaging plays a significant role in staging. Bone imaging using 99mTc MDP and 18F has established value in detecting metastatic bone disease. ▪ Similarly, several radiopharmaceuticals are used in staging and follow-up of neuroendocrine tumors. 13 Staging of Malignant Disease ▪ Although the ideal staging is a microscopic process, many times it is not possible to biopsy each and every lesion to find out whether they are malignant or not. ▪ Nuclear medicine procedures, especially 18F FDG-PET, have a higher degree of accuracy compared with CT or MRI alone in staging tumors particularly lymph node involvement. ▪ The accuracy of CT in staging mediastinal disease in lung cancer as an example is approximately 70 %; MRI is slightly higher at around 80 %, while 18F FDG accuracy is better than 90 %. 14