Positron-emission tomography-based staging is cost-effective in early-stage follicular lymphoma

Integration of PET/CT parameters and a clinical variable to predict the risk of progression of disease within 24 months (POD24) in follicular lymphoma

Background

Patients with follicular lymphoma (FL) who experience progression of disease within 24 months (POD24) of receiving first-line therapy had a significantly poorer prognosis than that without early progression. Due to the established prognostic relevance of positron emission tomography/computed tomography (PET/CT) parameters in FL and their clinical accessibility, we aimed to investigate the predictive role of PET/CT metabolism and dissemination parameters in POD24 for FL.

Methods

The POD24 status of 155 patients who underwent PET/CT examinations at initial diagnosis was evaluated. Various baseline characteristics were collected, along with PET/CT-derived parameters, including the maximum tumor dissemination (Dmax), maximum standardized uptake (SUVmax) value, total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG). A Cox proportional regression analysis was used to identify potential risk predictors of POD24. Receiver operating characteristic (ROC) curves were used to define the optimal cut-off values.

Results

In our cohort, POD24 was observed in 21 (13.5%) FL patients. The univariate and multivariate Cox regression analyses revealed that elevated lactate dehydrogenase (LDH) was a significant predictor of POD24. Additionally, survival analyses based on the cut-off values showed that the risk of POD24 was significantly increased in patients with a Dmax >64.24 cm, SUVmax >11.23, TMTV >144.16 cm2, and TLG >586.79 g. Further, a Dmax >64.24 cm, a TMTV >144.16 cm2, and elevated LDH were selected for inclusion in a risk model [concordance index (C-index) =0.82], and the patients were divided into three risk groups, in which the rates of POD24 were 1.69%, 10.42%, and 35.29%, respectively (P<0.001). Our model exhibited excellent performance in terms of both the C-index and ROC curve analysis, surpassing the performance of models commonly used in the field.

Conclusions

PET/CT parameters have prognostic value for POD24 in FL. The risk model, which combined PET/CT parameters with clinical indicators, could improve risk stratification and help guide therapeutic decisions.

Duodenal-type follicular lymphoma in 18F-FDG PET/CT imaging: a case report

Follicular lymphoma (FL) is a subtype of non-Hodgkin lymphoma (NHL) that is typically characterized by a slow-growing course. Duodenal-type follicular lymphoma (D-FL) was recently reclassified as a distinct variant. This subtype exhibits unique clinical and biological characteristics, which set it apart from other forms of FL. We report a case of a 36-year-old male patient with multiple, small, gray polypoid lesions in the descending duodenum which were detected by esophagogastroduodenoscopy. The pathological diagnosis was low-grade D-FL. 18F-FDG PET/CT was performed for staging and revealed the pancreas and peripheral lymph nodes were involved by FL, with a clinical IV stage. The patient underwent a bone marrow smear cytology, which revealed no bone marrow abnormalities, and excluded bone marrow involvement. He was treated with six cycles of chemotherapy using the R-CHOP regimen and reached complete remission.

Prognostic value of interim 18F-FDG PET/CT in adult follicular lymphoma treated with R-CHOP

PURPOSE

The prognostic value of interim ¹⁸F-FDG PET/CT (I-PET) for follicular lymphoma (FL) is controversial, and may be related to the lack of strict standards in terms of age, chemotherapy regimen, and evaluation criteria in previous studies. This study aimed to investigate the prognostic value of I-PET in adult FL patients treated with R-CHOP.

METHODS

I-PET was performed in 30 adult FL patients after treatment with 3-5 cycles of R-CHOP. PET/CT images were assessed using the Deauville 5-point scale (D-5PS) criteria. Baseline PET/CT (B-PET) was performed in 24 of the patients with FL before treatment. The PET/CT image parameters, such as the SUVmax, TLG, and tMTV, were recorded. The prognostic values of sex, age, grade, Ann Arbor stage, LDH level, and I-PET were evaluated.

RESULTS

Kaplan-Meier analysis and Cox regression showed that sex, age, grade, Ann Arbor stage, LDH, and I-PET using the D-5PS criteria could not predict the PFS of adult patients with FL treated with R-CHOP (P>0.05). ROC curve analysis evaluated the predictive values of SUVmax, TLG, and tMTV in B-PET and I-PET and showed that none of them was predictive of PFS in adult FL patients (P>0.05). However, the variation in SUVmax (∆SUVmax) was predictive of PFS in adult FL patients (AUC=0.83, P=0.040), and the cutoff threshold was 4.85.

CONCLUSIONS

I-PET using the D-5PS criteria cannot predict the PFS of adult FL patients treated with R-CHOP. However, the ∆SUVmax between B-PET and I-PET is applicable for the prognosis of adult patients with FL.