Figure 1
Fig 1
Axial T1-w SE (A) MR image show the lobulated cystic mass (arrowheads) located in the anterior and left presacral areas. Posteriorly there is a solid component (arrow)
Cystic lesion at retrorectal region
SectionAbdominal imaging
Case TypeAnatomy and Functional Imaging
Authors
Bintoudi A2, Chryssou E1, Karantanas A1
1. Departments of Medical Imaging, University Hospital, Heraklion-Greece and
2. Radiology, Papageorgiou Teaching Hospital, Thessaloniki-Greece
Connected authors
21 years, female
Clinical History
A 21-year-old woman was referred to our department due to worsening of clinical symptoms, namely pelvic pain, dyspareunia and constipation. The patient had been examined at another hospital 1 year before, because of moderate low abdominal pain. Ultrasound disclosed a pelvic cystic lesion, but she denied any intervention. A pelvic MR imaging examination was requested.
Imaging Findings
MR examination was performed at 1.5 Tesla scanner (Vision Hybrid, Siemens Erlangen, Germany) using a phased-array abdominal coil. The examination protocol included sagittal and axial TSE T2-w (TR/TE: 5300/110ms; slice thickness 4.0 mm), coronal STIR (TI/TR/TE:160/ 5360/130ms, slice thickness 4.0mm) and axial T1-w (TR/TE 598/12ms, slice thickness 4.0 mm) images. No intravenous media contrast was administered.
MR imaging revealed a multicystic lesion, sized 6.5x7x7cm, at the left ischiorectal region extending slightly to the right presacral area. The lesion was well defined with lobulated margins and showed with high signal intensity on all sequences without any fat suppression within it. There were also some solid components in the internal part of the wall of the lesion (Fig. 1). The findings were compatible with a tailgut cyst.
Surgical treatment was suggested based on MR imaging findings. The patient underwent complete surgical removal of the cyst with preservation of internal genitalia.
MR imaging revealed a multicystic lesion, sized 6.5x7x7cm, at the left ischiorectal region extending slightly to the right presacral area. The lesion was well defined with lobulated margins and showed with high signal intensity on all sequences without any fat suppression within it. There were also some solid components in the internal part of the wall of the lesion (Fig. 1). The findings were compatible with a tailgut cyst.
Surgical treatment was suggested based on MR imaging findings. The patient underwent complete surgical removal of the cyst with preservation of internal genitalia.
Discussion
A. Background
A tailgut cyst (TGC) is a rare developmental cystic anomaly which occurs mostly at the retrorectal and presacral regions. TGC has also been found in other anatomic areas, such as at the periphery of kidney or at the subcutaneous tissue [1]. The lesion is a congenital malformation that develops during 8th week of gestation. The pathogenesis of the lesion is associated with persistent of vestiges of the most caudal part of embryonic hindgut. If a tailgut remnant persists, then a true tailgut cyst will develop [1, 2]. TGC occurs more frequently in middle-age women (M/F:1/3), although cases in neonates have been reported [3].
B. Clinical Perspective
Patients present with anal pain, dyspareunia,constipation, abdominal pain. Because is mostly appear in women could be misdiagnosed as cystic lesion from internal genitalia. MR imaging can exclude pathology from ovaries, sacral spine or rectum.
C. Imaging Perspective
The TGC is typically a unilocular cyst with multiple small peripheral cysts with a thin, non-enhancing wall. A thicker wall may be formed due to the presence of a complication, such as infection or rarely because of malignant transformation. Malignant transformation into adenocarcinoma, sarcoma or neuroendocrine carcinoma of TGC has been rarely reported [4].
Macroscopically, TGC are well-defined cystic masses containing protein-rice, mucoidal material. TGC microscopically is a more complicated issue. Pathognomonic for the diagnosis of the TGC is the presence of multiple layers of different types of epithelium such as columnar, squamous, or transitional but mostly epithelium which produces mucin. Histologic verification is very important for the final diagnosis of the TGC due to the fact that other lesions, which commonly appear at this region, have similar radiologic appearance.TGC is not in contact with sacrum or ovaries so we can exclude anterior meningocele, epidermoid or dermoid cyst .The existence of myenteric plexus and serosa excludes the diagnosis of TGC.
D. Outcome
In our case, surgical treatment was suggested following the report of MR imaging. The patient underwent complete surgical removal of the cyst. At histology, a fibrotic wall with thin mucin-secreting epithelium was surrounded by a layer of smooth muscle and scarce elements of adipose tissue. No inflammation or malignancy was found.
E. Take Home Message, Teaching Points
Although the final diagnosis is based on histological findings, imaging with MRI at the region of interest is of great importance to characterise the lesion, establish the size and extensions of the lesion to nearby anatomical structures and evaluate possible infection or malignant transformation.
A tailgut cyst (TGC) is a rare developmental cystic anomaly which occurs mostly at the retrorectal and presacral regions. TGC has also been found in other anatomic areas, such as at the periphery of kidney or at the subcutaneous tissue [1]. The lesion is a congenital malformation that develops during 8th week of gestation. The pathogenesis of the lesion is associated with persistent of vestiges of the most caudal part of embryonic hindgut. If a tailgut remnant persists, then a true tailgut cyst will develop [1, 2]. TGC occurs more frequently in middle-age women (M/F:1/3), although cases in neonates have been reported [3].
B. Clinical Perspective
Patients present with anal pain, dyspareunia,constipation, abdominal pain. Because is mostly appear in women could be misdiagnosed as cystic lesion from internal genitalia. MR imaging can exclude pathology from ovaries, sacral spine or rectum.
C. Imaging Perspective
The TGC is typically a unilocular cyst with multiple small peripheral cysts with a thin, non-enhancing wall. A thicker wall may be formed due to the presence of a complication, such as infection or rarely because of malignant transformation. Malignant transformation into adenocarcinoma, sarcoma or neuroendocrine carcinoma of TGC has been rarely reported [4].
Macroscopically, TGC are well-defined cystic masses containing protein-rice, mucoidal material. TGC microscopically is a more complicated issue. Pathognomonic for the diagnosis of the TGC is the presence of multiple layers of different types of epithelium such as columnar, squamous, or transitional but mostly epithelium which produces mucin. Histologic verification is very important for the final diagnosis of the TGC due to the fact that other lesions, which commonly appear at this region, have similar radiologic appearance.TGC is not in contact with sacrum or ovaries so we can exclude anterior meningocele, epidermoid or dermoid cyst .The existence of myenteric plexus and serosa excludes the diagnosis of TGC.
D. Outcome
In our case, surgical treatment was suggested following the report of MR imaging. The patient underwent complete surgical removal of the cyst. At histology, a fibrotic wall with thin mucin-secreting epithelium was surrounded by a layer of smooth muscle and scarce elements of adipose tissue. No inflammation or malignancy was found.
E. Take Home Message, Teaching Points
Although the final diagnosis is based on histological findings, imaging with MRI at the region of interest is of great importance to characterise the lesion, establish the size and extensions of the lesion to nearby anatomical structures and evaluate possible infection or malignant transformation.
Differential Diagnosis List
Tailgut cyst with no evidence of malignant transformation
Epidermoid cyst
Dermoid cyst
Anterior meningocele
Rectal duplication cyst
Cystic lymphangioma
Final Diagnosis
Tailgut cyst with no evidence of malignant transformation
References
[1] Aflalo-Hazan V, Rousset P, Mourra N, Lewin M, Azizi L, Hoeffel C (2008) Tailgut cysts: MRI findings. Eur Radiol 18:2586–2593 (PMID: 18566821)
[2] Yang D, Park Hi Ch, Jin W et al ((200) Tailgut Cyst: MRI Evaluation. AJR Am J Roengenol 184:1519-1523 (PMID: 15855109)
[3] Hjermstad BM, Helwig EB (1998) Tailgut cyst. Report of 53 cases. Am J Clin Pathol 89:139-147 (PMID: 3277378)
[4] Graadt van Roggen JF, Welvaart K, De Ross A, Offerhaus GJ, Hogendoorn PC (1999) Adenocarcinoma arising within a tailgut cyst: clinicopathologic description, and follow up od an unusual case. J Clin Pathol 52:310-322 (PMID: 10474528)
[5] Karcaaltincaba M, Karcaaltincaba D, Ayhan A (2005) Diagnosis of Tailgut Cysts. AJR Am J Roengenol 185:1369-1370 (PMID: 16247171)
Case information
| URL: | https://www.eurorad.org/case/9964 |
| DOI: | 10.1594/EURORAD/CASE.9964 |
| ISSN: | 1563-4086 |
Figure 2
Fig 3
Sagittal T2-w TSE (C) and the coronal STIR (D) MR images, show the multi-locular apperance of the lesion (arrowheads) and its relations to the surrounding structures.
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Figure 3
Fig 2
Axial T2-w TSE MR (B) image. The lesion displaces the rectum to the right ( small open arrow) and the vagina anteriorly (large open arrow).
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Fig 1
Axial T1-w SE (A) MR image show the lobulated cystic mass (arrowheads) located in the anterior and left presacral areas. Posteriorly there is a solid component (arrow)
Departments of Medical Imaging, University Hospital, Heraklion-Greece
Departments of Medical Imaging, University Hospital, Heraklion-Greece
Fig 3
Sagittal T2-w TSE (C) and the coronal STIR (D) MR images, show the multi-locular apperance of the lesion (arrowheads) and its relations to the surrounding structures.
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Departments of Medical Imaging, University Hospital Heraklion-Greece
Departments of Medical Imaging, University Hospital Heraklion-Greece
Fig 2
Axial T2-w TSE MR (B) image. The lesion displaces the rectum to the right ( small open arrow) and the vagina anteriorly (large open arrow).
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Departments of Medical Imaging,University Hospital Heraklion Greece
Departments of Medical Imaging,University Hospital Heraklion Greece