Semi-Quantitative Characterization of Post-Transplant Lymphoproliferative Disorder Morphological Subtypes with...

Area of Science:

• Nuclear Medicine
• Oncology
• Transplant Surgery

Background:

• Post-transplant lymphoproliferative disorder (PTLD) is a serious complication following organ transplantation.
• PTLD is classified into nondestructive, polymorphic, monomorphic, and classic Hodgkin Lymphoma subtypes by the WHO.
• Differentiating PTLD subtypes is crucial for appropriate patient management.

Purpose of the Study:

• To evaluate the utility of semi-quantitative 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) PET/CT parameters in distinguishing PTLD morphological subtypes.
• To assess if SUVmax, SUVpeak, and SUVmean can differentiate between nondestructive, polymorphic, and monomorphic PTLD.

Main Methods:

• Retrospective analysis of 96 patients with histopathologically confirmed PTLD.
• Inclusion of baseline [¹⁸F]FDG PET/CT scans performed between 2009 and 2019.
• Extraction and analysis of semi-quantitative SUVmax, SUVpeak, and SUVmean values.

Main Results:

• Median SUV values were highest for monomorphic PTLD, followed by polymorphic and nondestructive subtypes.
• Significantly higher median SUVpeak at the biopsy site was observed in monomorphic PTLD compared to polymorphic and nondestructive subtypes (p ≤ 0.04).
• An SUVpeak ≥ 24.8 was consistently associated with monomorphic PTLD in this cohort, though considerable SUV overlap existed across subtypes.

Conclusions:

• Median SUVpeak at the biopsy site can help indicate monomorphic PTLD over other subtypes.
• Significant overlap in SUV values across PTLD morphologies suggests these parameters are indicative, not definitive.
• SUV-based parameters from [¹⁸F]FDG PET/CT cannot replace histopathological classification for PTLD diagnosis.