Bizarre parosteal osteochondromatous proliferation

Bizarre parosteal osteochondromatous proliferation
Other namesNora lesion or Nora disease[1][2]
SpecialtyOrthopedics
SymptomsPainless lump in finger or toe[1]
Risk factorsPossibly trauma in a minority[1]
Diagnostic methodMedical imaging[1]
Differential diagnosisMainly subungal exostosis[1]
TreatmentSurgical excision.[1]
PrognosisUp to 50% recur after surgery[1]
FrequencyRare,[2] <5% of cartilage tumors,[3] M=F[1]

Bizarre parosteal osteochondromatous proliferation (BPOP), also known as Nora's lesion,[4] is a type of non-cancerous bone tumor belonging to the group of cartilage tumors.[1][2][5] It is generally seen in the tubular bones of the hands and feet,[6] where it presents with a rapidly enlarging painless lump in a finger or toe.[1]

It is composed of bone, cartilage and spindle cells.[1] Some people report previous trauma.[1]

Diagnosis is by medical imaging.[1] Treatment is by surgical excision.[1] Up to 50% recur after surgery.[1]

It is rare,[2] and occurs more often in the 20s and 30s.[1] Combined with subungal exostosis, it accounts for less than 5% of cartilage tumors.[3] Males and females are affected equally.[1] The condition was first described by Frederick E. Nora in 1983.[6][7]

  1. ^ a b c d e f g h i j k l m n o p q WHO Classification of Tumours Editorial Board, ed. (2020). "Bizarre parosteal osteochondromatous proliferation". Soft Tissue and Bone Tumours: WHO Classification of Tumours. Vol. 3 (5th ed.). Lyon (France): International Agency for Research on Cancer. pp. 348–350. ISBN 978-92-832-4503-2.
  2. ^ a b c d Bocklage, Therese J.; Quinn, Robert; Verschraegen, Claire; Schmit, Berndt (2014). "16. Cartilaginous tumours of bones and joints". Bone and Soft Tissue Tumors: A Multidisciplinary Review with Case Presentations. London: JP Medical Ltd. p. 379. ISBN 978-1-907816-22-2.
  3. ^ a b Engel, Hannes; Herget, Georg W.; Füllgraf, Hannah; Sutter, Reto; Benndorf, Matthias; Bamberg, Fabian; Jungmann, Pia M. (March 2021). "Chondrogenic Bone Tumors: The Importance of Imaging Characteristics". RöFo: Fortschritte auf dem Gebiete der Röntgenstrahlen und der Nuklearmedizin. 193 (3): 262–275. doi:10.1055/a-1288-1209. ISSN 1438-9010. PMID 33152784.
  4. ^ Davies, A. Mark; Sundaram, Murali; James, Steven J. (2009). Imaging of Bone Tumors and Tumor-Like Lesions: Techniques and Applications. Springer Science & Business Media. p. 684. ISBN 978-3-540-77982-7.
  5. ^ "ICD-11 - ICD-11 for Mortality and Morbidity Statistics". icd.who.int. Retrieved 6 July 2021.
  6. ^ a b Mahajan, Sumit; Chandra, Rajesh; Mohan Lal, Yash (December 2012). ""Nora lesion" – Bizarre parosteal osteochondromatous proliferation". Journal of Clinical Orthopaedics and Trauma. 3 (2): 119–121. doi:10.1016/j.jcot.2012.07.001. ISSN 0976-5662. PMC 3872810. PMID 26403451.
  7. ^ Cite error: The named reference Nora1983 was invoked but never defined (see the help page).