Should Coccygectomy be done for a Tailgut Cyst (Retrorectal Hamartoma)?

Many patients come to see me for coccydynia (coccyx pain, tailbone pain).

Occasionally we discover that their pain seems to be coming from a mass, tumor, abscess, or similar problem. (We see these types of things in ~ less than 5% of our patients with coccyx pain.)

One such mass is called a Tailgut Cyst (Retrorectal Hamartoma).

Tailgut Cysts are Located Near the Coccyx 
  • This mass is typically located just in front of the coccyx or just below the coccyx, or sometimes in front of the lower sacrum.
Note: a ‘Tailgut’ Cyst is very different from a ‘Tarlov’ Cyst.
MRI is better than X-rays to see a Tailgut Cyst
  • Note that Tailgut Cysts fail to show up on plain x-rays, which is why advanced imaging studies such as MRI are often helpful and necessary in cases where coccyx pain is persisting or failing to improve with standard non-surgical treatments. (But the MRI needs to be done correctly! See: Link)
Excellent recent article on Tailgut Cysts
  • There was a recent (2019) research study and review article on this topic which was excellent. I recommend that you use the link below to read the full article, for free, at the Journal’s website. The journal is called: the Annals of Coloproctology.
  • Below are my summary points from the article (highlighting important points or quotes from the article, as part of Fair Use commentary):
Surgery is recommended for Tailgut Cysts, for a few reasons:
  • 1) to confirm the diagnosis,
  • 2) to make sure the mass is not a cancer,
  • 3) to avoid complications that can occur if left in place, such as infection or the mass turning into a cancer.
  • Important quote from the article:

“Surgical treatment is always required because of complications including malignant transformation, infection, and perianal fistula formation.”

Should Coccygectomy be done for a Tailgut Cyst (Retrorectal Hamartoma)?

On the topic of whether the surgery for a tailgut cyst should also include coccygectomy (surgical removal/amputation of the coccyx), this seems to be up for debate:

Debate persists about whether the coccyx should be removed with the cyst. Several studies advocate coccygectomy since it improves surgical exposure and decreases risk of recurrence assuming that the coccyx may harbor a nidus of totipotential cellular remnants that may cause recurrence [4, 26]. However, the concern that the coccyx will increase risk of recurrence has not been demonstrated in other studies, especially for cysts not adherent to the coccyx and that can be removed entirely without coccygectomy; hence, coccyx removal is not required [27]. Removal of coccyx was based on the cyst itself and not the coccyx harboring aberrant remnants of the postanal gut leading to cyst formation. Recent trials report preserving the coccyx unless en bloc resection is required for malignancy or cysts densely adhere to the coccyx. Based on our findings, we removed the coccyx for 4 patients: 3 due to the cyst adhering to the coccyx and 1 for a large cyst requiring a combined coccygectomy and lower sacrectomy; the latter cyst was malignant.”


  • Ann Coloproctol. 2019 Oct;35(5):268-274. doi: 10.3393/ac.2018.12.18. Epub 2019 Oct 31.
  • Single-center Experience of 24 Cases of Tailgut Cyst.
  • Sakr A1,2, Kim HS1, Han YD1, Cho MS1, Hur H1, Min BS1, Lee KY1, Kim NK1.
  • Author information: 1:  Division of Colorectal Surgery, Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
  • Author information: 2:  Colorectal Surgery Unit, Department of General Surgery, Mansoura Faculty of Medicine, Mansoura University Hospitals, Mansoura, Egypt.
  • Journal article on 24 Cases of Tailgut Cysts, 2019, Annals of Coloproctology
      Journal article on 24 Cases of Tailgut Cysts, 2019, Annals of Coloproctology

Also, below is a different link to a review article by different researchers who looked at 196 cases of Tailgut Cysts, and reported that as high as 26% of them became malignant (cancer). or

Reference: Nicoll K, Bartrop C, Walsh S, Foster R, Duncan G, Payne C, Carden C. Malignant transformation of tailgut cysts is significantly higher than previously reported: systematic review of cases in the literature. Colorectal Dis. 2019 Aug;21(8):869-878. doi: 10.1111/codi.14628. Epub 2019 Apr 30. PMID: 30932326.

COME FOR RELIEF: For more information on coccyx pain, or to be evaluated in-person at Dr. Foye’s Tailbone Pain Center in the United States, go to:

– Patrick Foye, M.D., Director of the Coccyx Pain Center, New Jersey, United States.

Patrick Foye, M.D.
Follow Me

Comments are closed.

Book Now Available! Click on the book to get it now:

Get the Book at