Ischiorectal fossa: benign and malignant neoplasms of this “ignored” radiological anatomical space

  • S. C. FariaEmail author
  • S. B. Elsherif
  • T. Sagebiel
  • V. Cox
  • B. Rao
  • C. Lall
  • P. R. Bhosale
Part of the following topical collections:
  1. CME articles



To review the pertinent anatomy and the imaging features of common and uncommon benign and malignant neoplasms and masses of the ischiorectal fossa.


The ischiorectal or ischioanal fossa is the largest space in the anorectal region. The benign neoplasms that develop in the ischiorectal originate from the different components that forms the fossa including vascular tumors such as aggressive angiomyxoma or hemangioma; neural tumors as plexiform neurofibroma or schwannoma; fat tumors as lipoma; skin/skin appendages tumors as hidradenoma papilliferum; smooth or skeletal muscle tumors as solitary fibrous tumor. The malignant neoplasms that develop in the ischiorectal fossa also originate from different components that forms the fossa including vascular tumors such as angiosarcoma, neural tumors as malignant granular cell tumor and malignant peripheral nerve sheath tumor; fat tumors as liposarcoma; smooth or skeletal muscle tumors as leiomyosarcoma, rhabdomyosarcoma, malignant PEComa, or undifferentiated pleomorphic sarcoma. Additionally, the ischiorectal fossa can also harbor secondary hematogenous metastases and be affected by direct invasion from neoplasms of adjacent pelvic organs and structures. Furthermore, other miscellaneous masses can occur in the ischiorectal fossa including congenital and developmental lesions, and inflammatory and infectious processes.


Knowledge of the anatomy, and the spectrum of imaging findings of common and uncommon benign and malignant neoplasms of the ischiorectal fossa is crucial for the radiologists during interpretation of images allowing them to make contributions to the diagnosis and better patient management.


Ischiorectal fossa Anorectal space Aggressive angiomyxoma Plexiform neurofibroma Liposarcomas Malignant granular cell tumors 



We thank Kelly Kage, medical illustrator at MD Anderson Cancer Center for the illustration provided in this article.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no disclosure or conflict of interests.

Ethical approval

No IRB approval was required.


  1. 1.
    Moore KL, Dalley AF, Agur AMR (2014) Clinically oriented anatomy. 7th edn. Williams & Wilkins, BaltimoreGoogle Scholar
  2. 2.
    Llauger J, Palmer J, Perez C, Monill JM, Ribe J, Moreno A (1998) The normal and pathologic ischiorectal fossa at CT and MR imaging. Radiographics 18 (1):61–82. Google Scholar
  3. 3.
    Hoeffel C, Crema MD, Azizi L, Lewin M, Monnier-Cholley L, Arrive L, Tubiana JM (2007) Magnetic resonance imaging of the ischiorectal fossa: spectrum of disease. J Comput Assist Tomogr 31 (2):251–257. Google Scholar
  4. 4.
    Hammer RP, Shrewsbury MM (1977) A reconsideration of the ischiorectal fossa. Diseases of the Colon & Rectum 20 (8):681–689. Google Scholar
  5. 5.
    Abu JI, Bamford WM, Malin G, Brown L, Davies Q, Ireland D (2005) Aggressive angiomyxoma of the perineum. International Journal of Gynecological Cancer 15 (6):1097–1100. Google Scholar
  6. 6.
    Satheshkumar T, Saklani AP, Banerjee D, Jones DRB (2003) Angiomyofibrosarcoma: A rare ischiorectal fossa swelling. Hospital Medicine 64 (4):244-245Google Scholar
  7. 7.
    Jeyadevan NN, Sohaib SAA, Thomas JM, Jeyarajah A, Shepherd JH, Fisher C (2003) Imaging Features of Aggressive Angiomyxoma. Clinical Radiology 58 (2):157–162. Google Scholar
  8. 8.
    Kransdorf MJ, Jelinek JS, Moser RP, Jr., Utz JA, Brower AC, Hudson TM, Berrey BH (1989) Soft-tissue masses: diagnosis using MR imaging. AJR American journal of roentgenology 153 (3):541–547. Google Scholar
  9. 9.
    Surabhi VR, Garg N, Frumovitz M, Bhosale P, Prasad SR, Meis JM (2014) Aggressive angiomyxomas: a comprehensive imaging review with clinical and histopathologic correlation. AJR American journal of roentgenology 202 (6):1171–1178. Google Scholar
  10. 10.
    Hosseinzadeh K, Heller MT, Houshmand G (2012) Imaging of the female perineum in adults. Radiographics 32 (4):E129–E168. Google Scholar
  11. 11.
    Arneja JS, Gosain AK (2008) Vascular malformations. Plastic and Reconstructive Surgery 121 (4):195E–206E. Google Scholar
  12. 12.
    Arbelo-Cruz N, Lisanti C, Walker K, Schwope R, Bui-Mansfield LT, Reiter M (2016) Anatomy and Pathology of the Ischiorectal Fossa. Contemporary Diagnostic Radiology 39 (17):1–7. Google Scholar
  13. 13.
    Ros PR, Eshaghi N (1991) Plexiform neurofibroma of the pelvis: CT and MRI findings. Magnetic Resonance Imaging 9 (3):463–465. Google Scholar
  14. 14.
    Jett K, Friedman JM (2010) Clinical and genetic aspects of neurofibromatosis 1. Genetics in Medicine 12 (1):1–11. Google Scholar
  15. 15.
    Halefoglu AM (2012) Neurofibromatosis type 1 presenting with plexiform neurofibromas in two patients: MRI features. Case Reports in Medicine 2012:1–3. Google Scholar
  16. 16.
    Mazzola CR, Power N, Bilsky MH, Robert R, Guillonneau B (2014) Pudendal schwannoma: A case report and literature review. Can Urol Assoc J 8 (3-4):E199–203. Google Scholar
  17. 17.
    Majbar A, Hrora A, Jahid A, Ahallat M, Raiss M (2016) Perineal schwannoma. BMC research notes 9 (1):304. Google Scholar
  18. 18.
    Pantè S, Terranova M-L, Leonello G, Fedele F, Ascenti G, Famulari C (2009) Perineal schwannoma. Canadian Journal of Surgery 52 (1):E8–E9Google Scholar
  19. 19.
    Chen S, Gaynor B, Levi AD (2016) Transischiorectal fossa approach for resection of pudendal nerve schwannoma: case report. J Neurosurg Spine 25 (5):636–639. Google Scholar
  20. 20.
    Munk PL, Lee MJ, Janzen DL, Connell DG, Logan PM, Poon PY, Bainbridge TC (1997) Lipoma and liposarcoma: Evaluation using CT and MR imaging. American Journal of Roentgenology 169 (2):589–594Google Scholar
  21. 21.
    SScurry J, Van Der Putte SCJ, Pyman J, Chetty N, Szabo R (2009) Mammary-like gland adenoma of the vulva: Review of 46 cases. Pathology 41 (4):372–378. Google Scholar
  22. 22.
    Filho EFA, de Carvalho AL, de Oliveira Costa PF, de Carvalho AC (2016) Resection of ischiorectal fossa tumors – surgical technique. Journal of Coloproctology 36 (3):179–183. Google Scholar
  23. 23.
    Chen X, Wu JT (2017) Imaging findings of big hidradenoma papilliferum in ischiorectal fossa: a case report. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL MEDICINE 10 (8):12693–12697Google Scholar
  24. 24.
    Handa Y, Yamanaka N, Inagaki H, Tomita Y (2003) Large Ulcerated Perianal Hidradenoma Papilliferum in a Young Female. Dermatologic Surgery 29 (7):790–792. Google Scholar
  25. 25.
    Yap T, Hamzah L, Oshowo A, Taylor I (2003) Myxoid solitary fibrous tumour of the ischiorectal fossa. European Journal of Surgical Oncology 29 (1):98–100. Google Scholar
  26. 26.
    Levy AD, Manning MA, Miettinen MM (2017) Soft-Tissue Sarcomas of the Abdomen and Pelvis: Radiologic-Pathologic Features, Part 2-Uncommon Sarcomas. Radiographics 37 (3):797–812. Google Scholar
  27. 27.
    Chun HJ, Byun JY, Jung SE, Kim KH, Shinn KS (1998) Benign solitary fibrous tumour of the pre-sacral space: MRI findings. British Journal of Radiology 71 (846):677–679. Google Scholar
  28. 28.
    Vossough A, Torigian DA, Zhang PJ, Siegelman ES, Banner MP (2005) Extrathoracic solitary fibrous tumor of the pelvic peritoneum with central malignant degeneration on CT and MRI. Journal of Magnetic Resonance Imaging 22 (5):684–686. Google Scholar
  29. 29.
    Zhang W-d, Chen J-y, Cao Y, Liu Q-y, Luo R-g (2011) Computed tomography and magnetic resonance imaging findings of solitary fibrous tumors in the pelvis: Correlation with histopathological findings. European Journal of Radiology 78 (1):65–70. Google Scholar
  30. 30.
    Shin SS, Jeong YY, Kang HK (2008) Myxoid solitary fibrous tumor of the retroperitoneum: MRI findings with the pathologic correlation. Korean J Radiol 9 (3):279–282. Google Scholar
  31. 31.
    Menassa-Moussa L, Kanso H, Checrallah A, Abboud J, Ghossain M (2005) CT and MR findings of a retrorectal cystic hamartoma confused with an adnexal mass on ultrasound. European Radiology 15 (2):263–266. Google Scholar
  32. 32.
    Yang DM, Park CH, Jin W, Chang SK, Kim JE, Choi SJ, Jung DH (2005) Tailgut Cyst: MRI Evaluation. AJR American journal of roentgenology 184 (5):1519-1523Google Scholar
  33. 33.
    Sritharan K, Ghani Y, Thompson H (2014) An unusual encounter of an epidermoid cyst. BMJ case reports 2014 (may13 1):bcr2014204186.
  34. 34.
    Kesici U, Sakman G, Mataraci E (2013) Retrorectal/Presacral epidermoid cyst: report of a case. The Eurasian journal of medicine 45 (3):207–210. Google Scholar
  35. 35.
    Fujimoto H, Murakami K, Kashimada A, Terauchi M, Ozawa K, Nosaka K, Arimizu N (1993) Large epidermal cyst involving the ischiorectal fossa: MR demonstration. Clinical Imaging 17 (2):146-148. Google Scholar
  36. 36.
    Kransdorf MJ, Jelinek JS, Moser RP, Jr., Utz JA, Brower AC, Hudson TM, Berrey BH (1989) Soft-tissue masses: diagnosis using MR imaging. AJR Am J Roentgenol 153 (3):541–547. Google Scholar
  37. 37.
    Kim HK, Kim SM, Lee SH, Racadio JM, Shin MJ (2011) Subcutaneous epidermal inclusion cysts: Ultrasound (US) and MR imaging findings. Skeletal Radiology 40 (11):1415–1419. Google Scholar
  38. 38.
    Deshmukh SP, Gonsalves CF, Guglielmo FF, Mitchell DG (2012) Role of MR imaging of uterine leiomyomas before and after embolization. Radiographics 32 (6):E251–E281Google Scholar
  39. 39.
    Casillas J, Joseph RC, Guerra Jr JJ (1990) CT appearance of uterine leiomyomas. Radiographics 10 (6):999–1007Google Scholar
  40. 40.
    Kim HG, Song YJ, Na YJ, Choi OH (2013) A case of torsion of a subserosal leiomyoma. J Menopausal Med 19 (3):147–150. Google Scholar
  41. 41.
    Odobasic A, Pasic A, Iljazovic-Latifagic E, Arnautalic L, Odobasic A, Idrizovic E, Dervisefendic M, Dedić L (2010) Perineal endometriosis: a case report and review of the literature. Techniques in Coloproctology 14 (S1):25–27. Google Scholar
  42. 42.
    Chene G, Darcha C, Dechelotte P, Mage G, Canis M (2007) Malignant degeneration of perineal endometriosis in episiotomy scar, case report and review of the literature. International Journal of Gynecological Cancer 17 (3):709–714. Google Scholar
  43. 43.
    Wiley DJ, Douglas J, Beutner K, Cox T, Fife K, Moscicki A-B, Fukumoto L (2002) External Genital Warts: Diagnosis, Treatment, and Prevention. Clinical Infectious Diseases 35 (2):S210–S224. Google Scholar
  44. 44.
    Billingham RP, Isler JT, Kimmins MH, Nelson JM, Schweitzer J, Murphy MM (2004) The diagnosis and management of common anorectal disorders. Current Problems in Surgery 41 (7):586–645. Google Scholar
  45. 45.
    Trombetta LJ, Place RJ (2001) Giant condyloma acuminatum of the anorectum: Trends in epidemiology and management: Report of a case and review of the literature. Diseases of the Colon & Rectum 44 (12):1878–1886. Google Scholar
  46. 46.
    Nelson Montaña C, Labra A, Schiappacasse G (2014) Giant condyloma acuminatum (Buschke-Lowenstein tumor). Series of seven cases and review of the literature. Revista Chilena de Radiología 20 (2):57-63Google Scholar
  47. 47.
    Singh VA, Gunasagaran J, Pailoor J (2015) Granular cell tumour: malignant or benign? SINGAPORE MEDICAL JOURNAL 56 (9):513–517. Google Scholar
  48. 48.
    Nasser H, Ahmed Y, Szpunar SM, Kowalski PJ (2011) Malignant granular cell tumor: a look into the diagnostic criteria. Pathol Res Pract 207 (3):164–168. Google Scholar
  49. 49.
    Fanburg-Smith JC, Meis-Kindblom JM, Fante R, Kindblom LG (1999) Malignant granular cell tumor of soft tissue - Diagnostic criteria and clinicopathologic correlation, (vol 22, pg 779, 1998). AMERICAN JOURNAL OF SURGICAL PATHOLOGY 23 (1):136Google Scholar
  50. 50.
    Osanai T, Ishikawa A, Ogino T, Yamakawa M (2004) Contrast-enhanced magnetic resonance imaging of malignant granular cell tumor with pathological correlation: a case report. Journal of Orthopaedic Science 9 (5):529–532. Google Scholar
  51. 51.
    Bhosale P, Wang J, Varma D, Jensen C, Patnana M, Wei W, Chauhan A, Feig B, Patel S, Somaiah N, Sagebiel T (2016) Can abdominal computed tomography imaging help accurately identify a dedifferentiated component in a well-differentiated liposarcoma? Journal of Computer Assisted Tomography 40 (6):872–879. Google Scholar
  52. 52.
    Gupta P, Potti TA, Wuertzer SD, Lenchik L, Pacholke DA (2016) Spectrum of fat-containing soft-tissue masses at MR imaging: The common, the uncommon, the characteristic, and the sometimes confusing. Radiographics 36 (3):753–766. Google Scholar
  53. 53.
    Wang TK, Chung MT (1998) Anorectal leiomyosarcomas. Journal of gastroenterology 33 (3):402–407Google Scholar
  54. 54.
    Mehta N, Konarski A, Rooney P, Chandrasekar C (2015) Leiomyosarcoma of the ischiorectal fossa: report of a novel sphincter and sciatic nerve sparing simultaneous trans-abdominal and trans-gluteal resection and review of the literature. J Surg Case Rep 2015 (3):rjv016–rjv016.
  55. 55.
    Reisner D, Amadi C, Beckman I, Patel S, Surampudi R (2014) Pelvic alveolar rhabdomyosarcoma in a young adult. Radiol Case Rep 9 (4):798. Google Scholar
  56. 56.
    Agrons GA, Wagner BJ, Lonergan GJ, Dickey GE, Kaufman MS (1997) From the archives of the AFIP. Genitourinary rhabdomyosarcoma in children: radiologic-pathologic correlation. Radiographics 17 (4):919–937.
  57. 57.
    Stever MR, Hernandez E, Sakas EL (1988) Malignant fibrous histiocytoma of the pelvis. Gynecologic Oncology 30 (2):285–290. Google Scholar
  58. 58.
    Mohan RP, Verma S, Siddhu VK, Agarwal N (2013) Malignant fibrous histiocytoma. BMJ Case Rep 2013.
  59. 59.
    Fletcher CD, Bridge JA, Hogendoorn PC, Mertens F (2013) WHO classification of tumours of soft tissue and bone. IARC Press, LyonGoogle Scholar
  60. 60.
    Hornick JL, Fletcher CDM (2006) PEComa: what do we know so far? Histopathology 48 (1):75–82. Google Scholar
  61. 61.
    Folpe AL, Mentzel T, Lehr HA, Fisher C, Balzer BL, Weiss SW (2005) Perivascular epithelioid cell neoplasms of soft tissue and gynecologic origin: a clinicopathologic study of 26 cases and review of the literature. Am J Surg Pathol 29 (12):1558–1575Google Scholar
  62. 62.
    Tirumani SH, Shinagare AB, Hargreaves J, Jagannathan JP, Hornick JL, Wagner AJ, Ramaiya NH (2014) Imaging Features of Primary and Metastatic Malignant Perivascular Epithelioid Cell Tumors. AMERICAN JOURNAL OF ROENTGENOLOGY 202 (2):252–258. Google Scholar
  63. 63.
    Durot C, Dohan A, Boudiaf M, Servois V, Soyer P, Hoeffel C (2017) Cancer of the Anal Canal: Diagnosis, Staging and Follow-Up with MRI. Korean J Radiol 18 (6):946–956. Google Scholar
  64. 64.
    Granata V, Fusco R, Reginelli A, Roberto L, Granata F, Rega D, Rotondo A, Grassi R, Izzo F, Petrillo A (2016) Radiological assessment of anal cancer: an overview and update. INFECTIOUS AGENTS AND CANCER 11 (1):1–9. Google Scholar
  65. 65.
    Roy AC, Wattchow D, Astill D, Singh S, Pendlebury S, Gormly K, Segelov E (2017) Uncommon Anal Neoplasms. SURGICAL ONCOLOGY CLINICS OF NORTH AMERICA 26 (1):143. Google Scholar
  66. 66.
    Scherrer A, Reboul F, Martin D, Dupuy JC, Menu Y (1990) CT of malignant anal canal tumors. Radiographics 10 (3):433–453. Google Scholar
  67. 67.
    Mahmud A, Poon R, Jonker D (2017) PET imaging in anal canal cancer: a systematic review and meta-analysis. BRITISH JOURNAL OF RADIOLOGY 90 (1080).
  68. 68.
    Casali PG, Stacchiotti S, Sangalli C, Olmi P, Gronchi A (2007) Chordoma. Current Opinion in Oncology 19 (4):367–370. Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • S. C. Faria
    • 1
    • 3
    Email author
  • S. B. Elsherif
    • 1
  • T. Sagebiel
    • 1
  • V. Cox
    • 1
  • B. Rao
    • 1
  • C. Lall
    • 2
  • P. R. Bhosale
    • 1
  1. 1.Department of Diagnostic RadiologyThe University of Texas M. D. Anderson Cancer CenterHoustonUSA
  2. 2.University of FloridaJacksonvilleUSA
  3. 3.HoustonUSA

Personalised recommendations