Tailgut cysts: CT and MR findings

Malignant transformation of perianal tailgut cyst: A case report

BACKGROUND

Tailgut cyst is a congenital enterogenous cyst that rarely undergoes malignant transformation. Its clinical manifestations mainly correlate to the mass effect caused by the development of cysts and the infections that originate from these. Furthermore, the complete resection of this cyst is curative. We report our diagnostic and treatment experience with one case of malignant transformation of a perianal tailgut cyst, which was initially misdiagnosed as perianal abscess.

CASE SUMMARY

A 72-year-old woman visited our institution with complaints of a refractory nonhealing lesion on the right hip, which repeatedly broke and suppurated for more than 70 years, and aggravated in 4 mo. The patient was given a diagnosis of refractory perianal abscess with repeated incision and drainage procedures. Computed tomography of the pelvic cavity revealed a giant perianal cyst. Subsequent biopsy revealed a tumor with moderate-to-severe glandular epithelial dysplasia, and suggested that this was derived from the developmental cysts in the posterior rectal space. After further clarifying the nature and extent of the tumor by magnetic resonance imaging, total cystic resection was performed. Postoperative histopathological examination confirmed the malignancy, dictating the investigators to add postoperative chemotherapy to the treatment regimen.

CONCLUSION

The malignant transformation of perianal tailgut cysts is very uncommon, and this should be differentiated from perianal abscess. Complete surgical removal is curative, and postoperative pathology may determine the necessity of additional postoperative chemotherapy or radiotherapy, which may be beneficial for preventing local recurrence and metastasis.

Retrorectal mucinous adenocarcinoma arising from a tailgut cyst: A case report and review of literature

BACKGROUND

Tailgut cysts are defined as congenital cysts that develop in the rectosacral space from the residue of the primitive tail. As a congenital disease, caudal cysts are very rare, and their canceration is even rarer, which makes the disease prone to misdiagnosis and delayed treatment. We describe a case of caudal cyst with adenocarcinogenesis and summarize in detail the characteristics of cases with analytical value reported since 1990.

CASE SUMMARY

A 35-year-old woman found a mass in her lower abdomen 2 mo ago. She was asymptomatic at that time and was not treated because of the coronavirus disease 2019 pandemic. Two weeks ago, the patient developed abdominal distension and right waist discomfort and came to our hospital. Except for the high level of serum carcinoembryonic antigen, the medical history and laboratory tests were not remarkable. Magnetic resonance imaging showed a well-defined, slightly lobulated cystic-solid mass with a straight diameter of approximately 10 cm × 9 cm in the presacral space, slightly high signal intensity on T2-weighted imaging, and moderate signal intensity on T1-weighted imaging. The mass was completely removed by laparoscopic surgery. Histopathological examination showed that the lesion was an intestinal mucinous adenocarcinoma, and the multidisciplinary team decided to implement postoperative chemotherapy. The patient recovered well, the tumor marker levels returned to normal, and tumor-free survival has been achieved thus far.

CONCLUSION

The case and literature summary can help clinicians and researchers develop appropriate examination and therapeutic methods for diagnosis and treatment of this rare disease.

Isolated lumbar intradural tailgut cyst: A case report and review of the literature

Tailgut cysts are rare developmental cysts arising from remnants of the embryological postnatal gut. Despite being frequently located in the presacral space, isolated cases of aberrant locations have been reported, including, perirenal, perianal, and subcutaneous sites, with only two cases of subdural tailgut cysts reported to date. The clinical course is often marked by linear growth, causing compression of the adjacent structures, however malignant transformation with carcinomatous features has been previously described. Hereby the authors describe a case of an intradural extramedullary tailgut cyst in a 33-year-old man presenting with progressive low back pain and signs of autonomic dysfunction, including urinary retention and bowel incontinence. Whole-spine MRI revealed an intrathecal cystic lesion located at L2-L3 level exhibiting hyperintensity on T2-weighted images not enhancing when contrast was administered. Laminectomy followed by tumor excision was performed and pathological analysis confirmed the diagnosis of tailgut cyst.

Retrorectal cystic hamartoma: A case report

Introduction

and importance: Retrorectal cystic hamartoma (RCH) is a rare congenital lesion of the presacral space, which is part of the vestigial cystic tumors often benign and predominantly in women. Generally asymptomatic, the appearance of symptoms such as pain or neurological disorders should raise suspicion of degeneration.

Case presentation

We report an unusual observation of a 62-year-old patient admitted for perineal pain evolving for 2 months associated with tenesma and chronic constipation. The digital rectal examination found a posterior bulge at 4 cm from the anal margin, without intraluminal lesion. Rectosigmoidoscopy had noted posterior extrinsic compression but no rectal tumor. Pelvic CT and MRI had shown a solidocystic formation of the retro-rectal and presacral spaces, related to an enteric cyst. The operation was performed by abdominal approach and the surgical exploration had found a bilobed cystic formation. The cystic mass was removed and the anatomopathological examination concluded that it was a cystic hamartoma with no sign of malignancy.

Clinical discussion

Retrorectal tumors develop in the space bounded anteriorly by the propria fascia of the rectum and posteriorly by the presacral fascia overlying the sacrum. Common in children and then often malignant, inversely, in adults, they are rare and most often benign tumors. They are generally asymptomatic with a predominance of females, unlike our observation where the patient was male with a symptomatology dominated by perineal pain and constipation. The discovery is incidental in the majority of cases, however, in some cases, these cysts may be revealed by complications. The lesion can be explored by transrectal or suprapubic ultrasound, MRI and CT scan. Rectoscopy and fistulography may complete the exploration in case of diagnostic doubt. The resection must be thorough and in monobloc because of the risk of recurrence and the approach depends on the location and the size of the lesion.

Conclusion

RCH is a rare benign lesion whose morphological characteristics seem quite stereotyped. A detailed postoperative anatomopathological examination allows the diagnosis to be made and, above all, to look for a site of malignant transformation. This is why a complete surgical removal is necessary to prevent recurrence.

Tailgut cyst adenocarcinoma

Tailgut cysts (TGCs) are rare congenital entities arising from remnants of the embryological postanal primitive gut. Malignancy in TGCs is rare, with the majority being adenocarcinomas and carcinoid tumors. A search of the published literature yielded only 27 cases of adenocarcinoma developing in TGCs. We described the case of a 54-year-old female who presented with complaints of pelvic and perineal pain of several weeks. After the initial work-up, a mass in the right presacral location was diagnosed. She underwent radical resection of the tumor, using a posterior approach. The lesion was removed en bloc with the middle rectum, coccyx, and sacrum (S4-S5). The histopathologic examination revealed an adenocarcinoma arising in a TGC, and the patient received adjuvant chemoradiotherapy. Our case underlines that diagnosing a TGC is difficult as it is a rare congenital lesion. Clinical examination may be challenging as TGCs present with various symptoms, which can mimic other commonly proctologic disorders. Patients should be referred to a tertiary center with experience in pelvic surgery and must be managed by a multidisciplinary approach to maximize successful treatment. The recommended treatment is surgical excision given the malignant potential of TGCs and their risk of causing local complications.

Malignant transformation of tailgut cysts is significantly higher than previously reported: systematic review of cases in the literature

AIM

The best treatment for tailgut cysts has not been firmly established. We report a systematic review of the cases in the available literature in order to provide an evidence base for treatment.

METHOD

A systematic search of articles wholly or partly in English was made of PubMed, Embase and Google Scholar; additional studies were discovered by searching reference lists and contacting authors directly. Search terms 'tailgut cyst', 'tail gut cyst', 'retrorectal hamartoma' and 'retrorectal tumour' were used for case reports or case series; no publication date restrictions were imposed. Only studies with histological confirmation of diagnosis and reporting the age and gender of patients were included. Papers were excluded by consensus between the first two authors.

RESULTS

A total of 196 individual cases were analysed in detail including 51 cases of neoplasia. The overall rate of neoplastic transformation was 26.6%. Although the male:female cyst incidence ratio was 1:4, men over 18 had a significantly greater relative risk of neoplasm at 1.94 (P = 0.0055). Radiological evidence of nodular thickening of the cyst wall significantly increased the relative risk of the presence of cancer (P = 0.0023).

CONCLUSIONS

Current orthodoxy that these are not dangerous embryological remnants is unfounded and may be false. The available data suggest the risk of malignant transformation is high and will apply to any residual tissue after excision. The same rationale behind total mesorectal excision in rectal cancer applies to tailgut cysts. Consequently they should be resected with similar oncological margins.

Tailgut Cyst and Perineal Hydatid Cyst: A Case Report with Multimodality Imaging Findings

A tailgut cyst is a rare developmental lesion and usually is located in the retrorectal or presacral space. Extrahepatic hydatid disease has been reported in several locations including the pelvis and it often poses a diagnostic challenge. There are very few reported cases of primary perineal hydatid cysts. We present the multimodality imaging findings of a tailgut cyst and concurrent perineal hydatid disease in a 32-year-old male patient.

The Malignant Transformation of Retrorectal Cystic Hamartomas With Blood Irregular Antibodies Positive: A Case Report

Retrorectal cystic hamartomas are rare congenital presacral lesions and malignancy is extremely rare. Although surgical excision is the essential for treatment, a unique feature of our case compared with previously reported tailgut cysts is that this patient's blood irregular antibodies are positive with higher operational risks.A 44-year-old woman presented to our department complaining of pelvic and perineal pain for 6 months. Computed tomography (CT) scan of the abdomen and pelvis demonstrated a well-demarcated hypodense, multilocular cystic lesion, 10 cm in size, in the presacral region of the right of the midline. We found her blood irregular antibodies were positive in the preoperative examination. So she quitted surgery. Exploratory laparotomy and incision and drainage of pelvic tumor were operated. Postoperative routine pathology showed: (retroperitoneal tumors) moderately differentiated adenocarcinoma. Combined with clinical symptom and imaging, malignant transformation of retrorectal cystic hamartomas (tailgut cysts) was diagnosed. Taking into account that cyst is not sensitive to radiotherapy, so tumor necrosis factor (TNF) and raltitrexed were infused into the cysts and 3 cycles oxaliplatin (130 mg/m) were completed. Now although the lesion is shrink, but yellow, viscous mucus still secrete constantly, 100 ml/w.Given surgical excision is the essential for treatment, complete surgical excision should be implemented as far as possible. But if surgery cannot be carried out like the presented case, systemic chemotherapy and local radiotherapy are also available, which can alleviate the symptoms of oppression and improve the quality of life partly.

Management of tailgut cysts in a tertiary referral centre: a 10-year experience

AIM

Tailgut cysts are rare congenital lesions typically presenting as presacral masses. A variable clinical presentation often leads to misdiagnosis and unsuccessful operations.

METHOD

A retrospective analysis was performed of tailgut cysts presenting to one surgeon at St Mark's hospital between 2003 and 2013. The patient demographic data and clinicopathological and radiological features, together with perioperative details and recurrence, were reviewed.

RESULTS

A total of 17 patients (15 women) with a median age of 35 (21-64) years were included in the study. The mean duration of symptoms before referral was 40 months, with sepsis predominating in 12 cases. Fifteen of the patients had previously undergone surgery (mean 2.9 procedures). A posterior surgical approach was adopted in all patients with a coccygectomy performed in 13. A loop colostomy was formed in three patients. Two of them went on to have a secondary pull-through operation after an initial failed local repair of rectal injury. One case was reported to show malignant degeneration on histological examination. There was one recurrence during a median follow-up period of 13 (3-36) months.

CONCLUSION

Tailgut cysts are an uncommon yet important cause of chronic perianal sepsis. Suspicion should be raised in a patient, usually female, presenting with a history of unsuccessful procedures. Diagnosis can be made by clinical assessment and MRI. Complete excision usually resolves the problem.

[Retrorectal vestigial cyst: a report of a case]

Les tumeurs rétro rectales kystiques et solides sont très variées et rare chez l'adulte. Elles sont dominées par les chordomes qui sont des tumeurs à malignité locale essentiellement observées chez les sujets de sexe masculin, alors les tumeurs kystiques vestigiales, sont souvent bénignes et prédominante chez la femme. Ces kystes congénitaux sont souvent asymptomatiques. L'apparition de symptôme à type des douleurs ou des troubles neurologiques devrait faire suspecter une dégénérescence. Une éventuelle surinfection tumorale peut poser le problème de diagnostic différentiel avec un abcès fistuleux, de traitement différent. Nous rapportons une observation insolite d'une patiente âgée de 52 ans explorée pour une lésion kystique retro rectale kystique en rapport avec un kyste vestigial traité chirurgicalement par voie trans sacrée. On se propose à travers cette observation insolite d’étudier les aspects diagnostique, évolutif et thérapeutique de ces lésions rares.

MRI evaluation of not complicated Tailgut cyst: Case report

INTRODUCTION

The Tailgut cyst (cystic hamartoma) is an uncommon congenital disease of presacral retrorectal space and is embryologically part of some forms of enteric cysts. It is a benign malformation, although cases have been described in neoplastic degeneration.

PRESENTATION OF CASE

A caucasian 24 year old female presented shortly after childbirth with hypogastric abdominal discomfort associated with rectal tenderness, bleeding and moderate urinary symptoms for about three weeks. No previous similar episodes were reported. The patient was not suffering from haemorrhoids or inflammatory disease of the gastrointestinal tract.

Clinical examination revealed no significant abnormalities or in the perianal area and gluteal surface.

Digital rectal examination was suspicious of the presence of a presacral retrorectal mass. However, it could not exclude a trans-sphinteric perianal fistula. There was no fistulous communication with the exterior and the pain seemed to be more pronounced in the rectum.

MRI, which has a diagnostic accuracy of 76–100% for the detection of any perianal fistulae, was performed and demonstrated the presence of a retrorectal cystic hamartoma (Tailgut cyst).

DISCUSSION

The most common retrorectal space cystic lesions includes epidermoid cysts, dermoid cysts and enteric cysts. It presents with pelvic pain, and sometimes with local abscess, secondary to a sinus cyst. There can also be a communication between Tailgut cyst and fistula; in the absence of primary infection may develop postinflammatory fibrosis. Radiological investigation is carried out by TRUS, CT and MRI. During MRI, on T1-weighted images, the signal intensity may change from hypointense to hyperintense as protein concentration increases, as well as in the case of bleeding. On T2-weighted images, signal intensity of mucinous fluids can decrease from highly hyperintense to hypointense with increasing protein concentration and viscosity.

CONCLUSION

MRI is a non-invasive useful imaging investigation with high diagnostic accuracy when a retrorectal cyst is suspected. Despite its rarity, Tailgut cyst should be considered, both for acute complications, like infection or bleeding, and for the risk, however infrequent, of neoplastic degeneration.

Uncommon primary pelvic retroperitoneal masses in adults: a pattern-based imaging approach

There is a broad spectrum of primary pelvic retroperitoneal masses in adults that demonstrate characteristic epidemiologic and histopathologic features and natural histories. These masses may be classified into five distinct subgroups using a pattern-based approach that takes anatomic distribution and certain imaging characteristics into account, allowing greater accuracy in their detection and characterization and helping to optimize patient management. The five groups are cystic (serous and mucinous epithelial neoplasms, pelvic lymphangioma, tailgut cyst, ancient schwannoma), vascular or hypervascular (solitary fibrous tumor, paraganglioma, pelvic arteriovenous malformation, Klippel-Trénaunay-Weber syndrome, extraintestinal GIST [gastrointestinal stromal tumor]), fat-containing (lipoma, liposarcoma, myelolipoma, presacral teratoma), calcified (calcified lymphocele, calcified rejected transplant kidney, rare sarcomas), and myxoid (schwannoma, plexiform neurofibroma, myxoma).Cross-sectional imaging modalities help differentiate the more common gynecologic neoplasms from more unusual masses. In particular, the tissue-specific multiplanar capability of high-resolution magnetic resonance imaging permits better tumor localization and internal characterization, thereby serving as a road map for surgery.

Malignant risk and surgical outcomes of presacral tailgut cysts

BACKGROUND

Presacral tailgut cysts are uncommon and few data exist on the outcomes following surgery.

METHODS

Patients undergoing tailgut cyst resection at the Mayo Clinic between 1985 and 2008 were analysed retrospectively. Demographic data, clinicopathological features, operative details, postoperative complications and recurrence were reviewed.

RESULTS

Thirty-one patients were identified (28 women), with a median age of 52 years. Seventeen patients were symptomatic and 28 had a palpable mass on digital rectal examination. Median cyst diameter was 4.4 cm. Four patients had a fistula to the rectum. Complete cyst excision was achieved in all patients; eight underwent distal sacral resection or coccygectomy. Postoperative complications occurred in eight patients but without 30-day mortality. Malignant transformation was present in four patients: adenocarcinoma in three and carcinoid in one. The cyst recurred in one patient after surgery for a benign lesion.

CONCLUSION

Presacral tailgut cysts should be removed due to the risk of malignant transformation.

Retrorectal Tumors: The Choice of Surgical Approach Based on a New Classification

Because retrorectal-presacral tumors differ in histologic origin, symptoms, and prognosis, and often involve various neighboring structures, successful treatment of this heterogeneous group of tumors depends on the surgical approach chosen and the specialist surgeons involved. We investigated whether a new classification of retrorectal tumors based on findings from CT and MRI would simplify presurgical planning. The clinical records of a series of 34 patients who underwent surgery for retrorectal tumors from 1989 to 2003 were reviewed. Two radiologists, who were blind to the patients’ records, separately reviewed the preoperative CT and MRI findings and classified tumors according to whether they arose from the presacral area (Group 1), sacrum or spinal cord growing anteriorly (Group 2), or rectum growing posteriorly (Group 3). The preoperative CT and MRI findings for the retrorectal tumors yielded the information required to allow surgery to be properly planned (surgical approach and need to involve various specialist surgeons) in nearly all cases: 17 of the 18 patients (94.5%) with tumors arising from the retrorectal space, all 12 of those with tumors arising from the sacrum or spinal cord, and all four of those with rectal tumors. With the findings yielded by currently available CT and MRI techniques, retrorectal tumors can be anatomically and topographically classified preoperatively so as to allow surgery to be adequately planned in advance and thus optimize the surgical resection.

Tailgut cysts: report of two cases

AIM

An illustration of the diagnosis and management of tailgut cysts.

MATERIALS AND METHODS

Two cases of tailgut cyst and a review of the literature.

RESULTS

A female patient presented with acute urinary retention with a retrorectal mass felt during rectal examination and confirmed on ultrasound and magnetic resonance imaging underwent surgical resection and histology confirmed a chronically inflamed mucoid fluid-filled cyst partly lined by non-keratinised squamous epithelium. A male patient with ureteric obstruction and a prerectal cyst found on ultrasound scan underwent computed tomography with biopsies, but without reaching a conclusive diagnosis. Surgical resection was carried out and histology showed a chronically inflamed mucoid fluid-filled cyst partly lined with columnar epithelium.

DISCUSSION

Tailgut cysts are a rare developmental abnormality arising from remnants of the embryological postanal gut. Usually presenting incidentally or with pressure symptoms in middle-aged females, tailgut cysts are often initially mistaken for other clinical entities. Magnetic resonance imaging helps to differentiate tailgut cysts from other retrorectal lesions and developmental cysts. Histologically, the cyst wall demonstrates a wide variety of epithelial types and has a malignant potential. Malignancy is difficult to rule out with imaging or biopsy.

CONCLUSIONS

Magnetic resonance imaging is the favoured imaging modality and surgical resection is recommended to relieve pressure symptoms, provide a definitive diagnosis and rule out malignancy.

Laparoscopic approach to retrorectal cyst

Retrorectal cysts are rare benign lesions in the presacral space which are frequently diagnosed in middle-aged females. We report here our experience with two symptomatic female patients who were diagnosed as having a retrorectal cyst and managed using a laparoscopic approach. The two patients were misdiagnosed as having an ovarian cystic lesion after abdominal ultrasonography. Computer tomography (CT) scan was mandatory to establish the diagnosis. The trocar port site was the same in both patients. An additional left oophorectomy was done for a coexisting ovarian cystic lesion in one patient in the same setting. There was no postoperative morbidity or mortality and the two patients were discharged on the 5th and 6th post operative days, respectively. Our cases show that laparoscopic management of retrorectal cysts is a safe approach. It reduces surgical trauma and offers an excellent tool for perfect visualization of the deep structures in the presacral space.

Tailgut cysts: MRI findings

Magnetic resonance imaging (MRI) features of 11 surgically resected pelvic tailgut cysts were analyzed with reference to histopathologic and clinical data. Homogeneity, size, location, signal intensity, appearance and presence of septa and/or nodules and/or peripheral rim and involvement of surrounding structures were studied. Histological examination demonstrated 11 tailgut cysts (TGC), including one infected TGC and one TGC with a component of adenocarcinoma. Lesions (3-8 cm in diameter) were exclusively or partly retrorectal in all cases but one, with an extension down the anal canal in five cases. Lesions were multicystic in all patients but one. On T1-weighted MR images, all cystic lesions contained at least one hyperintense cyst. The peripheral rim of the cystic lesion was regular and non or moderately enhancing in all cases but the two complicated TGC. Nodular peripheral rim and irregular septa were seen in the degenerated TGC. Marked enhancement of the peripheral structures was noted in the two complicated TGC. Pelvic MRI is a valuable tool in the preoperative evaluation of TGC.

Pediatric presacral masses

Various types of masses may affect the presacral area in children. A presacral mass may be congenital or developmental or may arise from inflammation. The mass may have neural, vascular, lymphatic, or mesenchymal origins and may be primary (as in focal disease) or systemic (as in multifocal disease). Because the clinical manifestations of presacral masses are often nonspecific, imaging plays an important role in the detection and differentiation of these masses. Information obtained from imaging is also critical for management, especially for surgical planning. For these reasons, it is important that radiologists be familiar with the anatomy of the presacral region and with the imaging features of the various lesions that may occur in this region in children. For the accurate interpretation of findings, radiologists also must know the specific advantages and limitations of each of the imaging modalities used to evaluate this category of abnormalities.

Tailgut Cyst (Retrorectal Cystic Hamartoma): Report of a Case and Review of the Literature

Tailgut cysts are rare congenital lesions arising from remnants of normally regressing postanal primitive gut. They often present in middle-aged women with perirectal symptoms and a retrorectal multicystic mass. These cysts have occasionally shown malignant transformation. We report a case of a tailgut cyst occurring in a 25-year-old African-American female. The differential diagnosis of a retrorectal mass is briefly explored, and the etiology, diagnostic strategy, and surgical approach for tailgut cysts is examined. We also report an extensive literature review to examine clinical characteristics and surgical data for 43 cases of tailgut cysts spanning 16 years.

Tailgut cyst: MRI evaluation

OBJECTIVE

The purpose of our study was to evaluate the MRI features of tailgut cysts in five patients.

CONCLUSION

Our results suggest that MRI may be useful in the diagnosis of tailgut cyst. A multilocular cystic mass in the presacral space is a characteristic MRI finding of tailgut cyst, which may also be revealed as a cystic mass consisting of a large cyst accompanied by a small peripheral cyst. However, further studies are necessary to establish the usefulness of MRI for evaluating tailgut cysts.

Tailgut cyst in a child

Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital lesion found in the presacral space. The lesion has been infrequently reported in the literature. We report the MRI findings of a tailgut cyst in a 2-year-old girl who presented with a sacral dimple and skin discoloration.

Carcinoid tumor arising in a tailgut cyst of the anorectal junction with distant metastasis: a case report and review of the literature

Tailgut cyst is a rare congenital presacral lesion and is believed to arise from the persistent remnants of the postanal gut. Malignancy occurring in a tailgut cyst is extremely rare, and to our knowledge only 5 cases of carcinoid tumor arising in a tailgut cyst have been reported in the literature to date. We report a sixth case of carcinoid tumor arising in a tailgut cyst. The patient was a 41-year-old woman who presented with perianal pain. Sigmoidoscopy showed a 2-cm submucosal mass located 4 cm above the anal verge. The mass was a multilocular cyst with gray-tan solid portions. The cyst was lined by ciliated columnar, squamous, and transitional epithelia with small foci of carcinoid tumor in the cystic wall. The carcinoid tumor showed a trabecular growth pattern with uniform oval or round cells containing fine chromatin and positive immunoreactivity for chromogranin, synaptophysin, and cytokeratin. This case was unique because the tumor occurred at the anorectal junction, not in the retrorectal space, and unlike previously reported cases showed aggressive behavior and distant metastases.

CT and MR findings of a retrorectal cystic hamartoma confused with an adnexal mass on ultrasound

We describe the imaging features of a tailgut cyst mistaken for an adnexal mass. A pelvic ultrasound in a 28-year-old woman showed a 10-cm hypoechoic left pelvic mass. Having not seen the left ovary, the radiologist concluded that the mass was an endometrioma. CT disclosed a retrorectal cystic lesion with wall calcifications and internal septa. MR confirmed the extra-ovarian location of the tumor, which was hyperintense on T2-weighted images and had an intermediate signal on T1-weighted images. Surgery revealed a retrorectal cystic hamartoma. Radiological diagnosis of a tailgut cyst requires first correct localization of the tumor and then differentiation from other retrorectal masses.

Presacral dermoid cyst with scanty fat component: usefulness of chemical shift and diffusion-weighted MR imaging

We present a case of a dermoid cyst located at the presacral space. Although CT and conventional MR (T1- and T2-weighted images) demonstrated a non-specific cystic mass with little evidence of calcification or fat, chemical shift and diffusion-weighted MR imaging suggested the presence of small amount of fat and abundant keratinoid substance within the tumor, respectively. Pre-operative diagnosis of dermoid cyst was made. The tumor was surgically resected and the diagnosis was confirmed. Chemical shift and diffusion-weighted MR imaging are useful in the diagnosis of dermoid cyst with little evidence of calcification and fat.

Unusual perirenal location of a tailgut cyst

The authors describe a case in which a tailgut cyst occurred at an unusual location in a 22-year-old woman referred for abdominal discomfort and urinary frequency. The left abdomen contained a palpable mass, found at imaging studies to be a homogeneous, unilocular and cystic, and anterior to the left kidney. After surgical excision, it was shown to be a tailgut cyst.

Retrorectal developmental cysts in adults: clinical and radiologic-histopathologic review, differential diagnosis, and treatment

Developmental cysts are the most common retrorectal cystic lesions in adults, occurring mostly in middle-aged women. They are classified as epidermoid cysts, dermoid cysts, enteric cysts (tailgut cysts and cystic rectal duplication), and neurenteric cysts according to their origin and histopathologic features. Although developmental cysts are often asymptomatic, patients may present with symptoms resulting from local mass effect (eg, constipation, rectal fullness, lower abdominal pain, dysuria), with a palpable retrorectal mass at digital rectal examination, or with a complication. Infection with fistulization, bleeding, and malignant degeneration are the major complications of developmental cysts. A well-defined, unilocular or multilocular, thin-walled cystic lesion is the main imaging feature. Uncommonly, a sacral bone defect and calcifications are associated with developmental cysts. The differential diagnosis includes cystic sacrococcygeal teratoma, anterior sacral meningocele, anal duct or gland cyst, necrotic rectal leiomyosarcoma, extraperitoneal adenomucinosis, cystic lymphangioma, pyogenic abscess, neurogenic cyst, and necrotic sacral chordoma. Complete surgical excision is indicated to establish the diagnosis and avoid complications.

Tailgut cyst in a neonate

Tailgut cyst is a rare lesion of developmental origin located in the retrorectal space, which usually presents as a multilocular cystic mass. It is usually found in adults, and neonatal cases are extremely rare. The authors report a tailgut cyst in a neonate that was found by prenatal ultrasonogram, which was like a teratoma in gross appearance.

[Vestigial retrorectal cyst in adults]

STUDY AIM

The aim of this retrospective study was to report three cases of retrorectal vestigial cyst in adults.

PATIENTS AND METHOD

From 1977 to 1999 retrorectal vestigial cyst (RVC) was diagnosed in our department in three women who were 28, 57 and 53 years of age, respectively. RVC was revealed by either pain (n = 2) that occurred in one case in a pregnant woman, or acute intestinal obstruction (n = 1). The patients were operated on using a perineal approach in two cases and an abdominal approach in one case.

RESULTS

One epidermoid cyst and two mixed cysts without any sign of malignancy were observed. Postoperative follow-up was simple in two patients, while complications occurred in the third one via an uretero-vaginal fistula which required uretero-vesical reimplantation. The first two patients, reviewed after a 1-year follow-up, had no functional trouble and no sign of recurrence.

CONCLUSION

Retrorectal vestigial cysts are very rare tumors with a risk for degeneration. Computerized tomography on nuclear magnetic resonance and endorectal ultrasonography allow detection of their structure and topography and help guide their surgical approach. In the absence of malignancy, wide excision, if possible without opening of the cystic wall, leads to good results.

Retrorectal cystic hamartoma: report of 5 cases with malignancy arising in 2

BACKGROUND

Retrorectal cystic hamartomas, or tailgut cysts, are rare congenital lesions that typically present as presacral masses. These lesions are frequently clinically unrecognized and misdiagnosed. Malignant change is extremely rare. Only 10 additional cases with associated malignancy were recovered from the literature. We describe the clinicopathologic features of 5 cases, including 2 cases with malignant transformation.

RESULTS

All patients were women (age range, 36-69 years). The most common symptoms were pain with defecation and rectal bleeding. One patient was asymptomatic. All lesions presented as multicystic presacral masses and all were surgically resected. The lesions varied in size from approximately 2 to 12 cm (average, 9.5 cm) and overall had similar histology composed of a variety of epithelial linings (stratified squamous, transitional, and simple or ciliated pseudostratified columnar). Skin adnexa, neural elements, and heterologous mesenchymal tissue, discriminators between retrorectal cystic hamartoma and teratoma, were not identified. Arising in association with the cysts was a focus of adenocarcinoma in one case and a neuroendocrine carcinoma in another.

CONCLUSIONS

The clinical diagnoses in our cases were often delayed, which in part may be due to unfamiliarity with this entity. The main diagnostic difficulty is distinction from presacral mature cystic teratomas and rectal duplication cysts. Tailgut cysts require complete surgical excisions to prevent future recurrences and to preclude possible malignant transformation. Meticulous gross examination and adequate sampling are important to document the exact nature of these cysts and to rule out possible coexisting malignancies, which may be focal.

MR imaging of complex tail-gut cysts

Retrorectal-cyst hamartomas (RCH) are rare developmental tail-gut cystic tumours of the retrorectal space, which occasionally undergo malignant transformation. We describe the magnetic resonance imaging (MRI) findings in two patients with RCH and in a third patient with unclassified sarcoma arising from a RCH. The RCH were hypointense or hyperintense on T1-weighted images and hyperintense on T2-weighted images; they did not enhance and they contained multiple septations. A solid component in the periphery of one cyst was markedly hypointense on T2-weighted images in keeping with fibrous material. The sarcoma arising from the wall of the RCH enhanced and was of intermediate signal intensity on all sequences. MR may help establish the diagnosis of RCH if an unenhanced cystic tumour is discovered in the retrorectal space and it can help detect those rare cases of malignant transformation of these developmental tumours.

Adenocarcinoma arising in a tailgut cyst: report of a case

We report herein the unusual case of a 66-year-old woman found to have adenocarcinoma arising in a tailgut cyst. The patient had been observed for 6 months following the discovery of a presacral cystic mass measuring 10 x 9 cm for which she had refused surgery. The serum tumor marker, carcinoembryonic antigen, became slightly elevated, and diagnostic imaging distinctly revealed a tumorous lesion with papillary projection into the cyst lumen. The cystic mass was then excised through the transsacral approach. The pathological findings were compatible with moderately differentiated adenocarcinoma arising in a tailgut cyst. This entity is extremely rare, and only six cases, including our own, have been reported in the English literature. Early complete excision is advised because it is almost impossible to determine for certain whether presacral cystic masses are benign or malignant prior to surgery.