Sunita Sonavane, Archi Agarwal1, Sneha Shah1, Nilendu Purandare1, Mehjaben1, Venkatesh Rangarajan1
Department of Nuclear Medicine and PET/CT, Radiation medicine centre, Bhabha Atomic research Centre, 1Department of Nuclear Medicine and PET/CT, Tata Memorial Hospital, Parel, Mumbai, Maharashtra, India
Objective: We report a case of extensive cutaneous neurofibromatosis with newly diagnosed leftt breast carcinoma, referred for 99mTc methylene diphosphonate (MDP) bone scan for staging.
Materials and Methods: Wholebody bone scintigraphy was performed 2-3 h post intravenous injection 20 mCi of 99mTc- MDP. 99mTc- DMSA (V) scan was performed 2 h post intravenous injection of 8 mCi of 99mTc- DMSA (V). High-resolution 256 × 256 delayed whole-body image were acquired in both the scans.
Results: 99mTc- MDP bone scan revealed no definite osteoblastic skeletal metastases. Mildly increased extraosseous activity accumulation in the multiple cutaneous neurofibromas of varing sizes was also noted. In view of gaint neurofibromas a 99mTc- DMSA (V) scan was performed to rule out malignant transformation, revealed mild to moderate diffusely increased radiotracer uptake in the multiple neurofibromas, however, none of the subcutaneous neurofibromas showed abnormal intense radiotracer concentration. Thus, 99mTc- DMSA (V) whole-body scintigraphy didnot suggest malignant transformation in any of the peripheral neurofibromas.
Conclusion: Comparing 99mTc MDP bone and 99mTc DMSA (V) scans, more number of neurofibromas noted in 99mTc DMSA (V) scan. This case highlights high negative predictive value of 99mTc DMSA (V) scan in evaluating malignant transformation in gaint neurofibromas in a case of extensive cutaneous neurofibromatosis.
