. 2024 Mar 21;14:1301979. doi: 10.3389/fonc.2024.1301979

Table 3.

Advantages and Disadvantages of PET-CT.

Advantages	Disadvantages
• Non-invasive procedure (2, 40). • Ability to assess metabolic activity of lesions with the lymph nodes and in extra-nodal sites (12, 40). • Capacity to assess the entire marrow including patchy disease outside the iliac crest along with extra-medullary disease (2, 4, 8, 40). • It provides the benefit of continuous non-invasive monitoring in situations of uncertainty.	• Radiation exposure (40). • Patient needs to be fasting with controlled glucose levels prior to PET-CT (40). • Areas with physiologically high FDG uptake such as the brain, heart, digestive and urinary collecting systems can mask underlying pathological uptake (40). • Receiving steroids, chemotherapy or radiation exposure prior to PET-CT can interfere with the imaging accuracy* (4, 40). • Age can influence the pattern of bone marrow FDG activity (3, 47, 48). • Lacks histological confirmation of disease involvement (3). • Not all FDG avid lesions are related to lymphomatous involvement, i.e., false positive results* (3). • PET-CT can miss bone marrow involvement in low-volume diseases or in cases of discordant bone marrow involvement with indolent lymphomas (4, 7, 12, 20, 49, 50). • Experience needed for accurate evaluation of uptake and interpretation regarding bone marrow involvement (12). • Using different types of scanners could result in different results **** (40).

Advantages

Disadvantages

• Non-invasive procedure (2, 40).
• Ability to assess metabolic activity of lesions with the lymph nodes and in extra-nodal sites (12, 40).
• Capacity to assess the entire marrow including patchy disease outside the iliac crest along with extra-medullary disease (2, 4, 8, 40).
• It provides the benefit of continuous non-invasive monitoring in situations of uncertainty.

• Radiation exposure (40).
• Patient needs to be fasting with controlled glucose levels prior to PET-CT (40).
• Areas with physiologically high FDG uptake such as the brain, heart, digestive and urinary collecting systems can mask underlying pathological uptake (40).
• Receiving steroids, chemotherapy or radiation exposure prior to PET-CT can interfere with the imaging accuracy* (4, 40).
• Age can influence the pattern of bone marrow FDG activity** (3, 47, 48).
• Lacks histological confirmation of disease involvement (3).
• Not all FDG avid lesions are related to lymphomatous involvement, i.e., false positive results*** (3).
• PET-CT can miss bone marrow involvement in low-volume diseases or in cases of discordant bone marrow involvement with indolent lymphomas (4, 7, 12, 20, 49, 50).
• Experience needed for accurate evaluation of uptake and interpretation regarding bone marrow involvement (12).
• Using different types of scanners could result in different results **** (40).

*The optimal timing of PET-CT following the exposure to chemotherapy and radiation therapy to minimize false positive or inaccurate results is three weeks after chemotherapy and 8-12 weeks following radiation exposure (40).

**Age’s effect on the bone marrow activity on PET-CT is controversial; there is not enough evidence to conclude on this point (3).

***False positive PET-CT can be seen with processes involving increased glucose metabolism and glycolysis, such as inflammation, infections, and granulomatosis diseases. Other causes of false positive PET-CT include bone marrow hyperplasia, such as in patients who use growth factors (e.g., Granulocyte stimulating factors (GCSF), TPO agonists and EPO agonists) or post-chemotherapy or in patients with cytopenia leading to bone marrow hyperactivity to compensate for the low cell counts (40). Some experienced radiologists are able to differentiate based on the FDG uptake pattern and imaging if the bone marrow’s uptake is reactive (3, 4, 7, 17).

****Using different scanners can lead to inaccurate results, especially when the scanner’s resolution is not optimal, leading to missing lesions below the scanner’s resolution (40).