The article presents recommendations on the use of ¹⁸F-FDG PET in oncology. The panel of experts concluded that ¹⁸F-FDG PET should be used as an imaging tool in addition to conventional radiologic methods such as CT or MRI. It should be used for the diagnosis of head and neck, lung, or pancreatic cancer and for unknown primary tumor. PET is also indicated for staging of breast, colon, esophageal, head and neck, and lung cancer and of lymphoma and melanoma. It should also be used to detect recurrence of breast, colorectal, head and neck, or thyroid cancer and of lymphoma. The panel found that ¹⁸F-FDG PET has limitations, including the potential for false-positive and false-negative results. False-positive results are commonly associated with uptake in infectious or inflammatory tissue. Normal variants such as the ureters, bowel, lymphatic tissue, thymus, brown fat, and muscle can also show uptake. Additionally, ¹⁸F-FDG PET has limited spatial resolution and may not be useful in assessing cerebral metastases from known primary neoplasms. The panel also discussed the rationale for the recommendations, noting that despite limitations, ¹⁸F-FDG PET is rapidly becoming an integral part of oncology practice in the United States, Europe, and other countries. The panel was composed of experts in clinical oncology, radiology, nuclear medicine, and outcomes research. They used a systematic review of the literature and evaluated the quality of evidence to develop their recommendations. The panel found that ¹⁸F-FDG PET is beneficial in detecting metastatic or recurrent breast cancer, but not for screening or diagnosing primary breast cancer. It is also beneficial in managing colorectal liver metastasis, but not for diagnosing primary colorectal carcinoma. The panel concluded that ¹⁸F-FDG PET is useful in detecting extrahepatic recurrence or local relapse, but the evidence is limited. The panel emphasized the importance of histopathologic examination to confirm any positive findings from ¹⁸F-FDG PET. They also noted that the quality of evidence for PET in oncology is moderate, and further research is needed to clarify its role in various clinical situations. The panel did not consider the cost-effectiveness of ¹⁸F-FDG PET.The article presents recommendations on the use of ¹⁸F-FDG PET in oncology. The panel of experts concluded that ¹⁸F-FDG PET should be used as an imaging tool in addition to conventional radiologic methods such as CT or MRI. It should be used for the diagnosis of head and neck, lung, or pancreatic cancer and for unknown primary tumor. PET is also indicated for staging of breast, colon, esophageal, head and neck, and lung cancer and of lymphoma and melanoma. It should also be used to detect recurrence of breast, colorectal, head and neck, or thyroid cancer and of lymphoma. The panel found that ¹⁸F-FDG PET has limitations, including the potential for false-positive and false-negative results. False-positive results are commonly associated with uptake in infectious or inflammatory tissue. Normal variants such as the ureters, bowel, lymphatic tissue, thymus, brown fat, and muscle can also show uptake. Additionally, ¹⁸F-FDG PET has limited spatial resolution and may not be useful in assessing cerebral metastases from known primary neoplasms. The panel also discussed the rationale for the recommendations, noting that despite limitations, ¹⁸F-FDG PET is rapidly becoming an integral part of oncology practice in the United States, Europe, and other countries. The panel was composed of experts in clinical oncology, radiology, nuclear medicine, and outcomes research. They used a systematic review of the literature and evaluated the quality of evidence to develop their recommendations. The panel found that ¹⁸F-FDG PET is beneficial in detecting metastatic or recurrent breast cancer, but not for screening or diagnosing primary breast cancer. It is also beneficial in managing colorectal liver metastasis, but not for diagnosing primary colorectal carcinoma. The panel concluded that ¹⁸F-FDG PET is useful in detecting extrahepatic recurrence or local relapse, but the evidence is limited. The panel emphasized the importance of histopathologic examination to confirm any positive findings from ¹⁸F-FDG PET. They also noted that the quality of evidence for PET in oncology is moderate, and further research is needed to clarify its role in various clinical situations. The panel did not consider the cost-effectiveness of ¹⁸F-FDG PET.