Introduction: Tailgut cysts, or retrorectal cystic hamartomas, are uncommon developmental lesions found in the theoretical space between the rectum and the sacrum. Frequently asymptomatic and incidentally detected, they occur predominantly in women. Compression of nearby structures may cause perineal and back pain and even obstructed labor. Case Report: We report a case of a 50-year-old man with prior coccygeal fracture who presented with dull perineal pain, worsened by prolonged sitting. MRI revealed a cystic mass, and surgical excision was performed via a posterior perineal approach. Postoperative recovery was uneventful apart from surgery-related increased perineal pain. Pathology demonstrated a retrorectal cystic hamartoma. Discussion: Tailgut cysts are thought to originate from the embryonic tail, which normally regresses by the eighth week of gestation. MRI is the preferred imaging modality, with cysts appearing hypointense on T1 and hyperintense on T2 images. Solid components or irregular cyst walls on imaging may suggest malignancy. Preoperative biopsy carries risks of hemorrhage, infection, and tract seeding. In purely cystic lesions, complete surgical resection without biopsy is preferred. A perineal approach is recommended for small lesions below S3, while abdominal and abdominoperineal approaches are needed for larger lesions and those superior to S3. Routine coccygectomy was previously thought necessary to prevent recurrence but is now understood to be avoidable unless needed for exposure or the cyst is adherent. Malignant transformation occurs in up to 27% of cases, with recurrence up to 16%. Complete excision is essential to prevent recurrence and obtain a definitive diagnosis. Conclusion: Tailgut cysts, the most common retrorectal tumors, are often asymptomatic. MRI is the preferred imaging modality. Complete surgical resection is crucial to prevent malignancy and recurrence. The role of preoperative biopsy is controversial, and routine coccygectomy is no longer recommended.

<p><strong>Background:</strong> Retrorectal cystic hamartoma, also known as a tailgut cyst, is a rare type of space-occupying lesion. It is a cystic hamartoma that predominantly forms in the retrorectal region and may serve as a potential etiology for anal neoplasia.<br /><strong>Case Presentation</strong>: A 58-year-old female patient was initially treated for a high-grade squamous intraepithelial lesion of the anal canal, which was surgically removed on May 20, 2023, followed by radiotherapy. She also had a known tailgut cyst with a fistula connecting it to the perianal skin at the 6 o’clock position in the lithotomy view. The cyst had been asymptomatic until then. As a prophylactic measure to prevent potential malignant transformation, the decision was made to excise the tailgut cyst. The operation was performed laparoscopically and included perianal mobilization of the fistula. During follow-up, the patient developed perianal pain. A computed tomography scan revealed a fluid collection at the site of the excised tailgut cyst. The collection was surgically drained and identified as a seroma without any signs of infection. The patient was discharged after 7 days and experienced no further long-term complications.<br /><strong>Conclusion</strong>: Retrorectal cystic hamartomas are rare and often asymptomatic. When symptomatic, they may present with lower abdominal pain, back pain, obstipation, urinary retention, or complications such as anal abscesses and fistulas. Research to date remains inconclusive regarding the incidence of malignant transformation.</p>

Retrorectal cystic hamartomas or tailgut cysts are rare congenital lesions which result from the non-regression of embryo remnants of the hindgut. In this case report we present a 4-year old female who was referred to our facility with a history of change in stool habit for 2 years characterized by pain during defecation and passage of flat shaped stool. Abdomino-pelvic CT scan suggested retrorectal cystic hamartoma which was successfully surgically excised through posterior sagittal approach. The final pathological diagnosis was retrorectal cystic hamartoma (tailgut cyst) with no evidence of malignancy.

Adenocarcinoma on retrorectal cystic hamartoma: An illustrative image for a very rare diagnosis

Background. Retrorectal tumors are a rare group of tumors that can be benign or malignant in origin; in most cases, they are asymptomatic. They mainly arise in the presacral space, which is limited by Waldeyer’s fascia posteriorly, the rectal fascia proper anteriorly, the ureters and lateral ligaments of the rectum laterally, the levator ani muscles and coccyx inferiorly, and the transition of the pelvic peritoneum between the second and third sacral segments superiorly. Magnetic resonance imaging (MRI) is crucial for diagnosis and surgical planning. Most retrorectal tumors require surgical treatment without preoperative biopsy. Here, we present a case of a retrorectal cystic hamartoma that was treated with surgery.Clinical case. Patient N., 45 years old, presented with suspected pelvic malformation. The patient reported experiencing pain in the sacrum area since May 2023, with no history of trauma. She sought medical help at a local polyclinic, where an ultrasound of the pelvic organs revealed a pelvic mass. The patient was then referred to an oncologist at the Multidisciplinary Clinical Medical Center “Medical City”. Physical examination showed no specific features, except upon rectal examination, where a non-displaced tumor measuring up to 2 cm was palpated along the posterior rectal wall. MRI of the pelvic organs confirmed the presence of a mass behind the lower ampullary rectum. Surgical treatment was subsequently performed, and the diagnosis of teratoma was confirmed through morphological and immunohistochemical studies.Conclusion. Early comprehensive diagnostics and an experienced surgical team are key factors for successful treatment of patients with retrorectal tumors.

Abstract Tailgut cyst, or retrorectal cystic hamartoma, is a rare congenital malformation originating from retrorectal or presacral space. It stands as an embryonic vestige of the hindgut’s postnatal component. Owing to its rarity, undiagnosed asymptomatic cases and diverse array of clinical presentations that potentially mimic other diseases, correct diagnosis is often delayed. It can present at any age but is most prevalent in middle-aged females, often remaining asymptomatic and eluding detection during digital rectal examinations. Postoperative histopathological examination is the definitive diagnostic method. This case report highlights an unusual presentation of a tailgut cyst as an underlying etiology for lower back pain in a 17-year-old female patient, emphasizing the importance of considering it as a potential differential diagnosis for intractable lower back pain, especially in young females. Timely recognition of this condition is pivotal for precise management and better patient outcomes.

Background: Tailgut cysts are rare congenital malformation lesions, also known as retrorectal cystic hamartoma is defined as a remnant part of postnatal hindgut. Because of their rare incidence and nonspecific presentation, tailgut cysts are misdiagnosed. The symptoms depend on the size and the location of the tumor. Surgical intervention is always required because of the complications of these tumors. Case Presentation: We report a 40-year-old female patient with an uneventful past surgical and medical history. Presented to the outpatient clinic with vague abdominal pain and constipation for 1 and a half years. The rectal digital examination, computed tomography abdomen, and pelvis with contrast and magnetic resonance imaging pelvis indicated the presence of the tailgut cyst, intraoperative we found two retrorectal cysts, and complete surgical resection using a posterior approach was performed. The histopathology examination showed a 5 * 5 cm cyst filled with putty-like material, defined as an epidermal inclusion cyst. The patient recovered well and was discharged 6 days after surgery. Out patient clinic follow up was uneventful and the patient was discharged from the surgical side. Conclusion: Tailgut cysts originate from the postanal gut of the embryo. These cysts are typically asymptomatic, surgical removal via a posterior or anterior approach is recommended once these lesions are detected due to the possibility of malignant development, infection, retrorectal abscesses formation, and rarely anal fistulas. A variety of surgical techniques can be employed, and the course of treatment can be customized to fit the anatomy and suspected lesion diagnosis of each patient.

Retrorectal cystic hamartomas (HCR) (“tailgut cyst” in English-language literature) are congenital cystic tumors derived from vestiges of the hindgut. Its incidence is low, being more frequent in adult women. They are variable in size, uni or multiloculated. They can be lined with several types of epithelia (squamous, transitional, mucinous,...) in a same cyst and can contain mucus. Lesions usually present during adulthood due to pain, discomfort, rectal bleeding, infection, or malignant transformation. The incidence of malignancy is low, being adenocarcinoma and neuroendocrine the most frequent tumors associated to HCR. We present a case of HCR associated with squamous cell carcinoma and discuss aspects of the treatment.

Retrorectal cystic hamartoma or "tailgut cyst" is a rare entity, resulting from embryonic remnants of the primary posterior intestine or Tailgut. Imaging essentially in slices allowed the diagnosis of the site and the anatomopathological approach of the lesion confirmed by the histological analysis of the operative parts. The main differential diagnoses are retrorectal teratoma, retrorectal epidermal cyst and rectal duplication. The main complications are recurrence, chronic inflammation leading to anal margin fistulas and carcinomatous degeneration. We report the case of a 40 year old female patient, with no particular pathological history, who consulted for pelvic heaviness

Summary: Retro-rectal cystic hamartoma or tailgut cyst is a benign tumor of congenital origin, which has a recurring potential and an enclosed malignancy. - Case of a 59-year-old patient with a potentially recurrent tumor of 14cm that exceeded the limits of the retro rectal region and progressed downwards to the right anal region and retro coccygeal, its excision, « supposed » complete and confirmed by CT scan post operatively, was performed via 3 ways. Relapse had occurred as “adenocarcinoma” 7 years later, probably from some tumor cells, and this recurrence confirmed the insufficiency of excising the tumor alone. In our study the databases of Pub Med, Google Scholar, Scopus, were consulted, the research was: Tailgut Cyst, Retrorectal tumors, and malignancy; we found 399 cases of which some were solitary and others published through series. The tumor would therefore not be as rare as we previously assumed. - We present an analysis trying to unveil recurrences and their malignant transformations in adults. We also propose preventive measures and possible treatments during and after surgery.

Retrorectal cystic hamartoma with extrapelvic extension

Sonological Appearance of a Tailgut Duplication Cyst (Retrorectal Cystic Hamartoma) in a Neonate.

Retrorectal cystic hamartomas are rare congenital lesions that can undergo malignant transformation, and adenocarcinoma is the most frequently described histological type. The authors describe a case of a 53-year-old female patient with a localized well-differentiated adenocarcinoma that developed in a retrorectal cystic hamartoma. The patient was submitted to surgery (a Kraske procedure), with an R1 resection, followed by adjuvant radio-chemotherapy. After 23 months of follow up, the patient remains free from disease recurrence. Given the rarity of this entity, this case allows us to reflect on the differential diagnosis, therapeutic approach and patients’ follow-up.

Abstract Objectives Tailgut cyst (TGC) is a rare congenital benign cystic lesion arising from a remnant of the embryonic postnatal hindgut. TGCs are typically multinodular, uncapsulated, but usually well circumscribed. TGCs are generally rare in adults and the majority of the lesions are benign. Malignant transformation is rare and malignancies reported include adenocarcinomas and neuroendocrine tumors. Methods A retrospective database search was conducted and coded as “tailgut cyst or retrorectal cystic hamartoma” to identify cases of possible TGC between January 2005 and January 2019. The search utilized the pathology files of Yale-New Haven Hospital using CoPath laboratory information system. Clinical and surgical data were gathered from the surgical pathology report and surgical operative note when available. Results A total of 13 cases (10 women) were identified with a median age of 51 years. All the specimens were obtained by surgical excision. Most of the cases were excised from the presacreal area (11 cases), and two cases were excised from the retrorectal area. The two cases resected from the retrorectal area had a malignant component. The first case was a 33-year-old female who had a 1.5-cm tailgut cyst that showed a multifocal neuroendocrine tumor (carcinoid); the resection margin was also positive. The second case was a 59-year-old female who had a tailgut cyst that showed mucinous adenocarcinoma; the resection margin was also positive. Conclusion Diagnosis of tailgut is sometimes challenging. Possible differential diagnoses in this location include teratoma, dermoid cyst, anterior sacral meningocele, and presacral abscess. Imaging is an important component of the initial workup. Surgical resection is the treatment of choice when the cyst grows in size and if a solid component is present. Exclusion of other benign entities and malignant transformation/component on histological examination is crucial.

Tailgut cysts, also called retrorectal cystic hamartomas, are rare findings that usually occur in the retrorectal space. The incidence is estimated to be about 1 in 40,000. The aim of our review is to evaluate the potential pitfalls in the diagnosis of this rare pathologic condition, according to diagnostic procedures for this rare but misleading and subtle entity. We conducted a Medline literature review of the English literature discussing tailgut cysts in female patients. We concentrated on imaging technology used for diagnosis in gynecologic patients. For our search, we used the key words “tailgut cyst”, “retrorectal cystic hamartoma”, “gynecology”, focusing on clinical presentation, imaging technology used for diagnosis, presence of malignancy, and misdiagnosis with more common gynecologic pathology. Our search revealed 143 articles during the years 1975–2016 and, of these, 30 articles describing 91 female patients were considered. We concluded that tailgut cyst should be included in the differential diagnosis of pelvic lesions in gynecologic patients.

Introduction: Retrorectal hamartomas are congenital lesions that typically present themselves as pre-sacred tumor masses. Clinical manifestations are light and highly variable at presentation time, often leading to diagnostic difficulties and surgical failure. Case Report: A case of 46-year-old female who is referred to neurosurgery by her medical assistant with a few months history of paresthesia and decreased left lower limb muscle strength and more recently symptoms of gastrointestinal disorders (constipation, tenesmus and feeling of false wills). Imaging studies revealed a pre-sacral tumor with suspicion of nerve dependence on S4 and cystic nature. She underwent partial resection of the capsule of the lesion and aspiration of its contents by multidisciplinary team abdominal approach (general surgery/neurosurgery). The anatomopathological examination revealed a retrorectal cystic hamartoma. During follow-up the patient again developed tenesmus, false desires and the paresthesias of the left leg reappeared. The imaging tests confirmed a recurrence of the retrorectal hamartoma. The patient was again operated for block excision, this time by posterior approach. Conclusion: This case highlights the importance of retrorectal hamartomas as a differential diagnosis of presacral masses and it shows the difficulty in obtaining its diagnosis and treatment.

Unusual Case of Voiding Symptoms and Constipation: Retrorectal Cystic Hamartoma

Tailgut cyst (retrorectal cystic hamartoma) is a rare known entity that has been described in the surgical and pathological literature. There may be delay in diagnosis and treatment owing to rarity and absence of definite features. We experienced an unusual case of retrorectal cystic hamartoma presenting as subcutaneous swelling and infected sinus along with true tail in sacrococcygeal region.

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 a 16 days female neonate presented with urine retention. the retrorectal or presacral space (4) and rarely in the perirenal area (2,3,5), the subcutaneous tissue in the anorectal region (6) and more rarely in the prerectal location. Microscopically, the tailgut cyst is characterized by the presence of a cysts lined with varying types of epithelium; columnar, mucin secreting epithelium predominates, while other areas of squamous and transitional epithelium often coexist (7). The differential diagnosis of cystic masses in this space includes sacrococcygeal teratoma, dermoid cysts and other complex ovarian masses, rectal duplication cysts, anterior meningoceles, cystic lymphangiomas and abscesses (8,9). There is an approximately 3:1 female preponderance of cases reported (4). Uncomplicated lesions are typically asymptomatic, and patients usually come to medical attention when the cyst becomes infected or when the lesion is incidentally discovered either radiologically or during physical examination. Perineal pain, pain with defecation, painless rectal bleeding, urinary frequency, and change in stool caliber have been reported. A few rare cases of malignant change associated with a tailgut cyst have been reported, but none in children to our knowledge (4,10,11). Few cases have been reported in children. The largest series by Hjermstad and Helwig (4) at the Armed Forces Institute of Pathology describes 53 cases of the entity collected during a 35-year period. Five cases demonstrating the CT and sonographic findings of tailgut cysts were described by Johnson et al. (12) at the Armed Forces Institute of Pathology. There are only a handful of reports of the MR findings of this entity in adults and only a few cases in the pediatric population (13).

CASE SUMMARY A 30-year-old asymptomatic female presented for IUD placement 5 months after an uncomplicated C-section. Ultrasound confirmed correct IUD placement but revealed a “complex pelvic mass” in the posterior cul-de-sac. Rectovaginal exam revealed a nontender soft tissue mass, 6-7cm in size, just to the right of the rectum and vaginal apex. Pelvic MRI showed a 7 cm mass deep in the right hemipelvis, felt to possibly represent an endometrioma, which remained unchanged on a 3-month follow-up study. Colonoscopy revealed extrinsic bowel compression but no mucosal changes. Due to recent pelvic surgery, the imaging characteristics of the mass, and the normal appearance of both ovaries, a gossypiboma was considered. Exploratory laparotomy revealed a right perirectal retroperitoneal mass containing copious amounts of keratin. The mass was excised and the patient had an uneventful recovery. IMAGING FINDINGS The initial and follow-up pelvic MR images demonstrated a well-defined, non-enhancing, ovoid lesion within the cul-de-sac which exerted mass effect on the uterus (Figure 1) and was distinct from both ovaries. The lesion exhibited high T2 and low T1 signal as well as several areas of linear low T2 signal internally with a somewhat “whorled” appearance (Figure 2). In addition, there was no signal loss on fat saturated images (Figure 3). Given these findings and the patient’s clinical history, the differential diagnosis included gossypiboma, retrorectal cystic hamartoma, epidermal inclusion cyst and endometrioma.