A neuroendocrine tumor arising in a tailgut cyst: Case report and literature review.

INTRODUCTION AND IMPORTANCE: Cystic lesions in the retrorectal space include developmental abnormality, inflammatory process, and tumor-relevant cysts. Among them, the tailgut cyst is the most common lesion which is featured by the complex epithelium lining the wall. It is generally accepted that tailgut cysts are embryonic residues and are mostly benign, but there are also reports about malignant transformation and even metastasis. CASE PRESENTATION: A 44-year-old female complained a sacrococcygeal discomfort more than one year. The imaging diagnosis was an infectious cyst. After surgery, a solid region was defined in a cyst. Morphologically, the region was composed of bland epithelia forming glandular or ribbon-like structure, with round nuclei and fine chromatin. Immunohistochemically, the cells were positive for CK7, CD56 and synaptophysin. The Ki-67-positive cells were about 1 %. The final diagnosis is a low-grade neuroendocrine tumor arising in a tailgut cyst. The patient was living without recurrence by the follow-up of 20 months after surgery. CLINICAL DISCUSSION: By reviewing the previously reported NET arising from tailgut cysts, we summarized 29 cases of neuroendocrine neoplasms that reported detailed information, and the majority are women. We found that the higher-grade tumor presented a higher tendency of distant metastasis or recurrence after surgery. Complete resection and full evaluation by pathologists are necessary to get a correct diagnosis and avoid disease progression. CONCLUSION: We reported the rare case of NET G1 arising from a tailgut cyst and reviewed relevant reports, in order to broaden differential diagnoses when an isolated mass is identified in the retrorectal space.

Minimally invasive approach for retrorectal tumors above and below S3: a multicentric tertiary center retrospective study (MiaRT study).

BACKGROUND: Retrorectal tumors are uncommon lesions developed in the retrorectal space. Data on their minimally invasive resection are scarce and the optimal surgical approach for tumors below S3 remains debated. METHODS: We performed a retrospective review of consecutive patients who underwent minimally invasive resection of retrorectal tumors between 2005 and 2022 at two tertiary university hospital centers, by comparing the results obtained for lesions located above or below S3. RESULTS: Of over 41 patients identified with retrorectal tumors, surgical approach was minimally invasive for 23 patients, with laparoscopy alone in 19, with transanal excision in 2, and with combined approach in 2. Retrorectal tumor was above S3 in 11 patients (> S3 group) and below S3 in 12 patients (< S3 group). Patient characteristics and median tumor size were not significantly different between the two groups (60 vs 67 mm; p = 0.975). Overall median operative time was 131.5 min and conversion rate was 13% without significant difference between the two groups (126 vs 197 min and 18% vs 8%, respectively; p > 0.05). Final pathology was tailgut cyst (48%), schwannoma (22%), neural origin tumor (17%), gastrointestinal stromal tumor (4%), and other (19%). The 90-day complication rates were 27% and 58% in the > S3 and < S3 groups, respectively, without severe morbidity or mortality. After a median follow-up of 3.3 years, no recurrence was observed in both groups. Three patients presented chronic pain, three anal dysfunction, and three urinary dysfunction. All were successfully managed without reintervention. CONCLUSIONS: Minimally invasive surgery for retrorectal tumors can be performed safely and effectively with low morbidity and no mortality. Laparoscopic and transanal techniques alone or in combination may be recommended as the treatment of choice of benign retrorectal tumors, even for lesions below S3, in centers experienced with minimally invasive surgery.

Analysis of the clinicopathological features of tailgut cyst with emphasis on the development of neoplastic lesions.

Tailgut cyst is a rare congenital cyst occurring in the retrorectal space and development of neoplastic lesions in tailgut cyst has been reported. Due to the rarity of the tumor, the histogenesis of neoplastic lesions in tailgut cyst has remained elusive. In the present study, the clinicopathological features of tailgut cyst were analyzed with a particular focus on the development of neoplastic lesions. The clinicopathological features of four patients with tailgut cyst (one female and three males) were retrospectively reviewed. No symptoms were present in two patients. Perineal discomfort, and constipation and urinary retention, were described in the other two patients, respectively. Magnetic resonance imaging showed that the cystic lesions were hypointense on T1- and hyperintense on T2-weigted images in all patients. Histopathological analysis revealed that all lesions were multilocular, and cystic walls were covered by squamous and ciliated epithelia without nuclear atypia. The development of neoplastic lesions was noted in two patients. Dysplastic change composed of piling-up proliferation of glandular cells with mild to moderate nuclear atypia was present in one patient, and invasive adenocarcinoma with a dysplasia component was observed in another patient. Dysplasia of the glandular cells, as seen in two patients in the present series, may be a precursor lesion of invasive adenocarcinoma; therefore, adenocarcinoma arsing in tailgut cyst may show a dysplasia-carcinoma sequence. While the reported incidence of neoplastic lesions in tailgut cysts is ~9% or less, their frequency remains to be accurately determined. Therefore, complete surgical resection is important for the management of patients with tailgut cyst. Additional clinicopathological and molecular studies with large cohorts may be required to clarify the histogenesis of neoplastic lesion in tailgut cyst.

Laparoscopic Resection Combined with a Transsacral Approach for a Recurrent Tailgut Cyst with a Refractory Fistula.

Tailgut cyst is a rare cystic disease of the anterior sacral surface and the remains of an embryonic tail gut. Tailgut cysts have a potential for malignancy, and complete resection with an adequate surgical margin is necessary. Even if incomplete resection does not result in recurrence of malignant disease, there is a risk of local infection leading to refractory fistulas. The optimal treatment for such refractory recurrent lesions has not been reported. We describe a case in which the combination of laparoscopic and transsacral approaches was effective for resecting a recurrent refractory fistula after incomplete resection of a tail gut cyst.

Liver metastases of a neuroendocrine tumor arising from a tailgut cyst treated with interventional locoregional therapies: a case report and review of the literature on recurrent cases.

A tailgut cyst is a rare, developmental cyst occurring in the presacral space. Although primarily benign, malignant transformation is a possible complication. Herein, we report a case of liver metastases after resection of a neuroendocrine tumor (NET) arising from a tailgut cyst. A 53-year-old woman underwent surgery for a presacral cystic lesion with nodules in the cyst wall. The tumor was diagnosed as a Grade 2 NET arising from a tailgut cyst. Thirty-eight months after surgery, multiple liver metastases were identified. The liver metastases were controlled with transcatheter arterial embolization and ablation therapy. The patient has survived for 51 months after the recurrence. Several NETs derived from tailgut cysts have been previously reported. According to our literature review, the proportion of Grade 2 tumors in NETs derived from tailgut cysts was 38.5%, and four of the 5 cases of Grade 2 NETs (80%) relapsed, while all eight cases of Grade 1 NETs did not relapse. Grade 2 NET may be a high-risk group for recurrence in NETs arising from tailgut cysts. The percentage of Grade 2 NETs in tailgut cysts was higher than that of rectal NETs, but lower than that of midgut NETs. To the best of our knowledge, this is the first case of liver metastases of a neuroendocrine tumor arising from a tailgut cyst that was treated with interventional locoregional therapies, and the first report to describe about the degree of malignancy of neuroendocrine tumors originating from tailgut cysts in terms of the percentage of Grade 2 NETs.

Malignant transformation of tailgut cyst to squamous cell carcinoma, a rare case with poor outcome.

Tailgut cyst, a type of retro-rectal cyst, is a rare condition requiring evaluation for malignant transformation. We report a case of squamous cell carcinoma arising in the retro-rectal cyst, in a 51-year-old female who underwent incomplete resection of the cyst and chemo-radiotherapy, subsequently became locally recurred and metastatic.

Cystic lesions of the retrorectal space.

Cysts of the retrorectal space comprise a heterogeneous group of rare lesions. Most develop from embryological remnants and include tailgut cysts, dermoid cysts, rectal duplication cysts, anal canal duplication cysts, sacrococcygeal teratomas and anterior meningocoele. Tailgut cyst is the most common cyst of developmental origin, usually presenting as a multilocular cystic mass with mucoid content and lined by multiple epithelial types. Compared with tailgut cysts, rectal duplication cysts display all layers of the large bowel wall including a well-defined muscularis propria. Retrorectal cysts of non-developmental origin are far less common and represent lesions that either infrequently involve the retrorectal space or undergo extensive cystic change. This review provides an overview of the various histological types of cystic lesions of the retrorectal space, divided into cysts of developmental origin and those of non-developmental origin. A practical pathological and multidisciplinary approach to diagnosing these lesions is presented.

Mucinous adenocarcinoma arising from a tailgut cyst: A case report.

BACKGROUND: Retrorectal hamartomas or tailgut cysts (TCs) are rare. In most cases, they are asymptomatic and benign; however, rarely, they undergo malignant transformation, mainly in the form of adenocarcinoma. CASE SUMMARY: A 55-year-old woman presented to our hospital with lower back pain. On magnetic resonance imaging, a large pelvic mass was found, which was located on the right of the ischiorectal fossa, extending to the minor pelvis. The patient underwent extensive surgical resection of the lesion through the right buttock. Histological examination confirmed the diagnosis of a retrorectal mucinous adenocarcinoma originating from a TC. Surgical resection of the tumour was complete, and the patient recovered without complications. The pilonidal sinus was then excised. One year later, semi-annual positron emission tomography-computed tomography and magnetic resonance imaging scans did not reveal any evidence of local recurrence or metastatic disease. CONCLUSION: Preoperative recognition, histological diagnosis, and treatment of TCs pose significant challenges. In addition, the possibility of developing invasive mucinous adenocarcinoma, although rare, should be considered.

Neuroendocrine Tumor of Tailgut Cyst with Unexpected Metastases.

Neuroendocrine tumors (NETs) originate from the neuroendocrine cells, which are found in various organs. NETs occur frequently in the gastrointestinal tract. NETs arising from tailgut cysts are uncommon. We herein report an interesting case of metastatic tailgut cyst NET, which was firstly diagnosed as plasmacytoma.

Perianal Tailgut Cyst: An Unusual Presentation.

A tailgut cyst (TGC) is a rare congenital lesion that occurs due to failure of involution of the distal hindgut, leading to the development of a mucus-secreting cyst. The clinical presentation is nonspecific, and often the diagnosis can be missed. We present the case of a 20-year-old female with a TGC in the perianal region. Surgical excision of the cyst was performed, followed by an uneventful recovery. The young age of our patient and the anatomical location of the TGC make our case a rare entity, highlighting the need for practicing surgeons to keep TGC as a differential in mind while examining masses in the perianal region.

[Neuroendocrine tumor associated with an intestinal cyst: a case report]. / Tumor neuroendocrino asociado con quiste intestinal: presentación de un caso.

Intestinal (tailgut) cysts or retrorectal cystic hamartomas are rare benign lesions that are included in the category of developmental cystic lesions. Their origin is still uncertain, although several hypotheses have been proposed to explain their development. They are located mainly in the presacral (retrorectal) space and predominately affect middle-aged women (40-60 years). Taking into account location and histological characteristics, the main differential diagnoses include epidermoid cysts, duplication cysts and teratomas. Malignant transformation of these lesions is rare and preferentially into adenocarcinoma and neuroendocrine tumors. We present a case of an intestinal cyst associated with a well-differentiated neuroendocrine tumor (G1) in a 63-year-old woman.

Mucinous adenocarcinoma of a tailgut cyst.

A tailgut cyst is a rare congenital lesion that develops from a residual posterior remnant of the intestine and presents as a mass in the presacral space. They are generally asymptomatic or have atypical symptoms, are usually benign but may rarely become malignant. We report a case of a 37-year-old female who initially presented to the Surgical Department of Korle Bu Teaching Hospital, Accra, Ghana with a malignant tailgut cyst after having repeated surgical procedures for recurrent perianal infective pathologies but still had persistence of symptoms. The lesion was initially excised and found to be a dermoid cyst histologically. The mass recurred after a year and had a re-excision; the lesion was diagnosed histologically as mucinous adenocarcinoma. This report emphasizes the different forms of presentation of a patient with a tailgut cyst and the possibility of malignant transformation, as well as the presentation of this tailgut cyst which can be diagnosed using radiological investigations and histological findings. Funding: None.

An Unusual Perianal Presentation of a Tailgut Cyst.

Tailgut cysts or retrorectal cystic hamartomas are rare, congenital, development lesions arising from the remnants of the hindgut during embryogenesis. It is most often misdiagnosed due to its rarity, variable clinical presentation, and malignant potential. The following report describes an unusual case of a tailgut cyst in a 60-year-old male with a history of a perianal mass for 12 years. Surgical resection was done, and histopathological examination revealed a multiloculated cyst filled with brownish fluid, grossly, and a cyst lined by various epithelia such as stratified squamous epithelium, pseudostratified columnar epithelium, and flattened to cuboidal and mucin-secreting columnar epithelium along with cyst wall made up of bundles of smooth muscles, microscopically. Several lesions mimic a tailgut cyst and need to be excluded from the differentials. Although no malignancy was documented in this case, these cysts have been known to undergo malignant transformation into adenocarcinoma and neuroendocrine carcinoma, to name a few. This warrants a thorough and accurate histopathological assessment and mandatory follow-up.

Recurrent retrorectal tailgut cyst mimicking deep pelvic abscess: A diagnostic dilemma.

Tailgut cysts are congenital anomalies that are rare and arise from incompletely regressed primitive hindgut. These are more commonly found in women and are usually asymptomatic. When symptoms develop, these can present with pain, infection, hemorrhage, difficulty in defecation, and rarely malignant change. We report a middle-aged married woman who presented with deep-seated perineal pain for a couple of months, which increased during defecation and sexual intercourse. Although abdominal examination was unremarkable barring deep tenderness in the hypogastrium, rectal and vaginal examinations suggested a tender pelvic swelling. An abdominal ultrasonographic examination diagnosed a cystic swelling in the pelvis extending until the Levator ani muscles. Considering her symptoms, a pelvic abscess was diagnosed and transvaginal drainage was done. Due to persistence of symptoms and recurrence after a month, she was further investigated and was diagnosed to have a presacral benign cystic tumor based on CT and MRI scans of the pelvis. The lesion was completely excised through a combined abdomino-perineal approach and histopathological report suggested a benign tailgut cyst. That a cystic presacral swelling with features of inflammation can be confused with a deep pelvic abscess is hereby highlighted in this report. An MRI scan is diagnostic of these lesions. Failure to differentiate it from a pelvic abscess may result in drainage, which may be of concern if the lesion is malignant.

Promoting Laparoscopic Anterior Approach for a Very Low Presacral Primary Neuroendocrine Tumor Arising in a Tailgut Cyst.

BACKGROUND: Tailgut cysts are rare congenital lesions that develop in the presacral space. As they can potentially conceal primary neuroendocrine tumors, surgical excision is suggested as the treatment of choice. However, specific management guidelines have yet to be developed. A posterior approach is usually preferred for cysts extending to the third sacral vertebral body. Conversely, a transabdominal approach is preferred for lesions extending upward to achieve an optimal view of the surgical field and avoid injuries. CASE REPORT: Here, we report a case of a 48-year-old man suffering from perianal pain and constipation. Digital rectal examination and magnetic resonance imaging revealed a presacral mass below the third sacral vertebral body. A laparoscopic transabdominal presacral tumor excision was performed. The final histological diagnosis was a rare primary neuroendocrine tumor arising from a tailgut cyst. The postoperative course was uneventful, and no signs of recurrence were observed at the six-month follow-up. CONCLUSIONS: This study may help establish more well-grounded recommendations for the surgical management of rectal tumors, demonstrating that the laparoscopic transabdominal technique is safe and feasible, even for lesions below the third sacral vertebral body. This approach provided an adequate view of the presacral space, facilitating the preservation of cyst integrity, which is essential in cases of malignant pathologies.

Retrorectal Tailgut Cyst: A Case Report.

Tailgut cysts, or retrorectal cystic hamartomas, are rare congenital abnormalities that develop when the embryologic tailgut fails to involute. They are found in the presacral space, which is an area with quite a complex anatomy. Tailgut cysts can be symptomatic due to their mass effect and can even result in complications, including malignancy. Because of their rarity and varied presentations, tailgut cysts are frequently misdiagnosed. CT scans and MRI are useful in the diagnosis of these retrorectal masses, and surgical resection is the definitive treatment. Multiple surgical approaches can be used, with the treatment tailored to suit each individual patient's anatomy and suspected lesion diagnosis.

Risk of malignancy and outcomes of surgically resected presacral tailgut cysts: A current review of the Mayo Clinic experience.

AIM: The aim of this study was to describe the surgical management, outcomes and risk of malignancy of presacral tailgut cysts. METHOD: A retrospective analysis of all patients who underwent resection of tailgut cyst at Mayo Clinic in Arizona, Florida and Minnesota between 2008 and 2020 was performed. Demographics, presentation, evaluation, surgical approach, postoperative complications, pathology and recurrence rates were reviewed. RESULTS: Seventy-three patients were identified (81% female) with a mean age of 45 years. Thirty-nine patients (53%) were symptomatic, most commonly with pelvic pain (26 patients). Digital rectal examination identified a palpable mass in 68%. Mean tumour size was 6 cm. Resection was primarily performed through a posterior approach (77%, n = 56), followed by a transabdominal approach (18%, n = 13) and a combined approach (5%, n = 4). Six patients underwent a minimally invasive resection (laparoscopic/robotic). Coccygectomy or distal sacrectomy was performed in 41 patients (56%). Complete resection was achieved in 94% of patients. Thirty-day morbidity occurred in 18% and was most commonly wound related; there was no mortality. Malignancy was identified in six patients (8%). For the 30 patients with follow-up greater than 1 year, the median follow-up was 39 months (range 1.0-11.1 years). Local recurrence was identified in three patients and distant metastatic disease in one patient. CONCLUSION: The rate of malignancy in presacral tailgut cysts based on this current review was 8%. Overall recurrence was 5% at a median of 24 months.

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.

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.