Correlation between 18 F-FDG PET/CT semiquantitative parameters and Ki-67 expression in pulmonary mucosa-associated lymphoid tissue lymphoma.

INTRODUCTION

This study aims to investigate the correlation between 18 F-Fluoro-d-glucose positron emission tomography/computed tomography (18 F-FDG PET/CT) semiquantitative parameters and Ki-67 expression in pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma.

METHODS

Twenty-eight patients with histologically confirmed pulmonary MALT lymphoma in 29 lesions who underwent 18 F-FDG PET/CT were retrospectively analysed. PET/CT images were analysed visually and semiquantitatively by measuring maximum standardized uptake value (SUVmax ), mean standardized uptake value (SUVmean ), metabolic tumour volume (MTV) and total lesion glycolysis (TLG). The correlation between morphological pattern, tumour size, Ki-67 expression and PET/CT semiquantitative parameters were also analysed.

RESULTS

There were 16 male patients (57.1%) and 12 female patients (42.9%), and the mean age was 57.6 ± 9.7 years (range 43-73 years). Twenty-nine pulmonary lesions were identified in 28 patients: 12 (41.4%) presenting as consolidation, 9 (31.0%) as nodules, 5 (17.2%) as masses and 3 (10.3%) as ground glass opacities (GGOs). All of the 29 lesions were 18 F-FDG avid. SUVmax of the lesions was 4.4 ± 3.0 (range 1.1-15.3), SUVmean was 2.8 ± 1.9 (range 0.8-10.3), MTV was 15.9 ± 17.6 (range 0.9-82.1) and TLG was 48.7 ± 56.6 (range 0.9-205.6). The PET/CT semiquantitative parameters were not correlated with morphological pattern of pulmonary MALT lymphoma, which were correlated significantly with tumour size and Ki-67 expression.

CONCLUSION

Pulmonary MALT lymphomas are 18 F-FDG avid, and 18 F-FDG PET/CT semiquantitative parameters (SUVmax , SUVmean , MTV and TLG) are significantly correlated with tumour size and Ki-67 expression. 18 F-FDG PET/CT plays a potential role in identifying lung MALT lymphomas with higher proliferation and more aggressive behaviour in clinical practice.