Neuroscience conference 2022

Marco Poloni

IRCCS Mario Negri, Italy

Title: The differential diagnosis of neurofibromatoses


Neurofibromatoses are neurocutaneous diseases with similar pathogenesis. The first description of NF1 is due to von Recklinghausen in 1882, while a NF2 case was described since 1822 but remained joined to NF eponym since 100 years later, as its central variant; only in 1993 these diseases were recognized as totally different, being carried by different chromosomes (17 for NF1, 22 for NF2), respectively encoding Neurofibromin and Merlin or Schwannomin, both proteins with tumor suppression activity; both diseases display autosomal dominant transmission and exhibit high rate of penetrance with mosaicism in several (20-30 %) cases; mutations of SMARCB1 and LZTR1 genes have been described typical of Schwannomatosis. NF1 is much more frequent than NF2, featuring cutaneous, sub-cutaneous and plexiform neurofibromas, Lish nodules, café-au-lait macules (CALMS), freckling, learning disabilities and skeletal malformations together with Central Nervous System and Spinal tumors (glioma, astrocytoma and meningioma); 10% possibility of malignant transformation exists. Neurologic, cognitive and Psychiatric abnormalities are significant and will reviewed much more deeply. The cardinal manifestation of NF2 is bilateral cochlear-vestibular schwannoma with additional tumors (cranial nerves and radicular schwannoma, meningioma, brain or spinal ependymoma); cutaneous signs are less frequent than in NF1, but the prognosis, due to brain tumors, is worst. In Schwannomatosis several schwannomas tipically arise on peripheral nerves with pain spontaneous or at pressure; VIII°nerve tumors are lacking. Imaging diagnostic is extremely useful to localize di focal areas of T2 hyperintensity and their extension corresponding to NF1 amartomas or tumors; on the contrary a strict follow-up of lesions in NF2 by cranial and spinal MRI is always mandatory while imaging by Total Body MRI or PET is required for the diagnosis in schwannomatosis. Differential diagnosis includes the Legius syndrome, carried by chromosome 15, displaying cutaneous alterations like NF1, learning disabilities, but no tumor predisposition; other diseases featuring CALMS exists together with peculiar tissue abnormalities, like Noonan, Watson and Leopard syndromes; on the other hand Proteus syndrome, known also as “Elephant-man”, is characterized by asymmetrical tissue overgrowth with deformities. 


Poloni Marco in Bergamo with his studio has become an important point of reference for those who need advice and practical assistance in the case of disorders related to the nervous system. With an experience of over 40 years in the sector, as well as an excellent training, this study brings with it important principles and values ??such as the health and well-being of the patient first of all. For this reason, the services provided aim to analyze each individual case in detail. Careful diagnosis and related and adequate treatment follows. The diagnoses of this neurologist in Bergamo are dictated by the experience made in prestigious universities such as those of Milan and Pavia, as well as specific research studies carried out in the laboratory. Poloni Marco carried out a period of research in the Neurological Clinic of the Karolinska Hospital in Stockholm where he was able to study an experimental model of amyotrophic lateral sclerosis from lead poisoning. Later, the research activity of this neurologist Bergamofocused on the study of amyotrophic lateral sclerosis and the role that phosphoric esters and thiamine play in this and other degenerative diseases of the nervous system. Recently, Poloni began to deal with neurofibromatosis, both clinically and scientifically. Marco Poloni is the editor and co-editor of 4 printed volumes and has in his name numerous publications concerning works in international and national journals, reports and communications at conferences and various chapters on teaching or research books.