The Clinical Utility of FDG PET-CT in Evaluation of Bone Marrow Involvement by Lymphoma

FDG PET/CT versus Bone Marrow Biopsy for Diagnosis of Bone Marrow Involvement in Non-Hodgkin Lymphoma: A Systematic Review

The management of non-Hodgkin lymphoma (NHL) patients requires the identification of bone marrow involvement (BMI) using a bone marrow biopsy (BMB), as recommended by international guidelines. Multiple studies have shown that [18F]FDG positron emission tomography, combined with computed tomography (PET/CT), may provide important information and may detect BMI, but there is still an ongoing debate as to whether it is sensitive enough for NHL patients in order to replace or be used as a complimentary method to BMB. The objective of this article is to systematically review published studies on the performance of [18F]FDG PET/CT in detecting BMI compared to the BMB for NHL patients. A population, intervention, comparison, and outcome (PICO) search in PubMed and Scopus databases (until 1 November 2021) was performed. A total of 41 studies, comprising 6147 NHL patients, were found to be eligible and were included in the analysis conducted in this systematic review. The sensitivity and specificity for identifying BMI in NHL patients were 73% and 90% for [18F]FDG PET/CT and 56% and 100% for BMB. For aggressive NHL, the sensitivity and specificity to assess the BMI for the [18F]FDG PET/CT was 77% and 94%, while for the BMB it was 58% and 100%. However, sensitivity and specificity to assess the BMI for indolent NHL for the [18F]FDG PET/CT was 59% and 85%, while for the BMB it was superior, and equal to 94% and 100%. With regard to NHL, a [18F]FDG PET/CT scan can only replace BMB if it is found to be positive and if patients can be categorized as having advanced staged NHL with high certainty. [18F]FDG PET/CT might recover tumors missed by BMB, and is recommended for use as a complimentary method, even in indolent histologic subtypes of NHL.

Performance of Positron Emission Tomography-Computed Tomography and Bone Marrow Biopsy in Detecting Bone Marrow Infiltration in Lymphoma Cases

Objective:

Bone marrow infiltration (BMI) affects the stage diagnosis, and treatment of lymphoma. We aimed to evaluate the performance of bone marrow biopsy (BMB) and positron emission tomography-computed tomography (PET/CT) in detecting BMI in lymphoma patients.

Materials and Methods:

A total of 269 non-Hodgkin’s lymphoma (NHL) and 110 Hodgkin’s lymphoma (HL) patients were evaluated retrospectively. Sensitivity, negative predictive value (NPV), and accuracy were calculated for PET/CT and BMB in detecting BMI.

Results:

Sensitivity, NPV, and accuracy for PET/CT in detecting BMI in NHL cases were 65%, 78%, and 84.4%, respectively, while they were 55%, 73.4%, and 79.9% for BMB. PET/CT performance for diffuse large B-cell lymphoma and follicular lymphoma was better than that of BMB, whereas the performance of BMB was better for mantle-cell lymphoma, Burkitt’s lymphoma, and primary mediastinal B-cell lymphoma. Sensitivity, NPV, and accuracy for PET/CT in HL cases were 91.3%, 97.75%, and 98.18%, respectively, while they were 56.52%, 89.69%, and 90.91% for BMB. Due to BMB, 43 (15.9%) patients in the NHL group and 2 (1.8%) patients in the HL group were protected from downstaging.

Conclusion:

Although their results vary according to NHL subtypes, PET/CT and BMB are complementary methods in determining BMI. In HL, PET/CT is an important diagnostic tool for detecting BMI, and BMB is not necessary in a significant proportion of cases.

Comparison of the RECIST and PERCIST criteria in solid tumors: a pooled analysis and review

The PET Response Criteria in Solid Tumors (PERCIST) is a new method for the quantitative assessment of metabolic changes in solid tumors. The assessments of tumor response between the RECIST and PERCIST have shown considerable difference in several studies. This pooled study was conducted to compare tumor response according to the two criteria in patients with solid tumors. We surveyed MEDLINE, EMBASE and PUBMED for articles with terms of the RECIST or PERCIST from 2009 and January 2016. There were six articles comparing the RECIST and PERCIST. A total of 268 patients were recruited; 81 with colorectal cancer, 60 with lung cancer, 48 with esophageal cancer, 28 with breast cancer, 14 with basal cell carcinoma, 12 with stomach cancer, 10 with head and neck cancer, and 16 with other rare cancers. The agreement of tumor response between the RECIST and PERCIST was moderate (k = 0.590). Of 268 patients, 101 (37.7%) showed discordance in the tumor responses between two criteria. When adopting the PERCIST, tumor response was upgraded in 85 patients and downgraded in 16. The estimated overall response rates were significantly different between two criteria (35.1% by RECIST vs. 54.1% by PERCIST, P < 0.0001). In conclusion, this pooled analysis demonstrates that the concordance of tumor responses between the RECIST and PERCIST criteria is not excellent. The PERCIST might be more suitable for assessing tumor response than the RECIST criteria.

Comparison of the RECIST and EORTC PET criteria in the tumor response assessment: a pooled analysis and review

PURPOSE

The EORTC PET criteria (EORTC criteria) are used to assess metabolic tumor response in patients with solid tumors. We conducted this pooled study to compare tumor responses according to the RECIST and EORTC criteria.

METHODS

Electronic databases were searched for eligible articles with the terms of "RECIST" or "EORTC criteria". We found seven articles with the data on the comparison of tumor responses by the RECIST and EORTC criteria.

RESULTS

A total of 181 patients were recruited from the seven studies. Ninety-two patients (50.8%) received cytotoxic chemotherapy and 89 were treated with targeted agents. The agreement of tumor responses between the RECIST and EORTC criteria was moderate (k = 0.493). Of 181 patients, 66 (36.5%) showed disagreement in the tumor responses: tumor response was upgraded in 54 patients and downgraded in 12 when adopting the EORTC criteria. The estimated overall response rates were significantly different between the two criteria (52.5% by the EORTC vs. 29.8% by the RECIST, P < 0.0001). When comparing the two criteria according to the anti-cancer treatments (chemotherapy or targeted therapy), the levels of agreement in tumor responses were not excellent (k = 0.461 for chemotherapy and k = 0.524 for targeted therapy, respectively) regardless of therapeutic types.

CONCLUSION

This pooled study indicates that the concordance of tumor responses between the RECIST and EORTC criteria is not excellent. When adopting the EORTC criteria instead of the RECIST, the overall response rate was significantly increased.