Imaging of presacral masses--a multidisciplinary approach

Benign ectopic prostate-a rare differential for a presacral mass

A man in his mid-40s presented to the colorectal surgery clinic with complaints of chronic perianal pain for over 20 years. He had episodes of urinary incontinence associated with pain. There were no other symptoms to suspect bowel pathology. On examination, he was found to have a tender mass in the retro-rectal plane without any evidence of rectal mucosal irregularity. He underwent an MRI of the pelvis, which showed a well-defined T2 hyperintense partly cystic lesion in the presacral region abutting the mesorectal fascia and a normal prostate gland. With a suspicion of a tailgut cyst or a duplication cyst, he underwent an excision of the presacral mass. Intraoperatively, there was a 2 × 2 cm well-defined firm, cystic lesion anterior to the fifth sacral vertebra and coccyx. The lesion was adherent to the mesorectum and was excised. On histopathology, there were features of muscular stroma and bilayered glandular epithelium with clear cytoplasm conclusive of a benign ectopic prostate.

Retroperitoneal anatomy with the aid of pathologic fluid: An imaging pictorial review

The retroperitoneum, a complex anatomical space within the abdominopelvic region, encompasses various vital abdominal organs. It is compartmentalized by fascial planes and contains potential spaces critical in multiple disease processes, including inflammatory effusions, hematomas, and neoplastic conditions. A comprehensive understanding of the retroperitoneum and its potential spaces is essential for radiologists in identifying and accurately describing the extent of abdominopelvic disease. This pictorial review aims to describe the anatomy of the retroperitoneum while discussing commonly encountered pathologies within this region. Through a collection of illustrative images, this review will provide radiologists with valuable insights into the retroperitoneum, facilitating their diagnostic proficiency to aid in appropriate patient clinical management.

Pediatric presacral tumors with intraspinal extension: a rare entity with diagnostic challenges

The presacral space is a potential space located between the rectum and the lumbosacral spine. It contains various primitive germ cell types that serve as the origin for a range of tumors. Imaging is crucial in characterizing, assessing the extent of and evaluating the treatment response to these tumors. We report a series of six cases of pediatric presacral tumors with intraspinal extension, including an immature sacrococcygeal teratoma (Altman type II), a malignant sacrococcygeal teratoma (Altman type IV), a neuroblastoma, a rhabdomyosarcoma, a clear cell sarcoma and an Ewing's sarcoma of the ilium. These tumors can be broadly categorized as tumors of germ cell, neuroblastic, mesenchymal and osteogenic origin. Despite overlapping imaging features, a review of the existing literature and careful retrospective observation revealed several distinctive features that aid in the optimal characterization of tumors. These include the tumor's epicenter, the pattern and degree of bone involvement, the status of sacral foramina and neural elements, and internal tumor characteristics such as the presence of fat, calcification, hemorrhage and necrosis.

A Case Report of Neuroendocrine Tumor in Presacral Region: How Can It Be Managed? Laparoscopy versus Laparotomy

Presacral or retrorectal tumors are rare, usually asymptomatic, and diagnosed accidentally during physical examination or imaging. Symptomatic tumors may present with perianal pain, bowel dysfunction, and urinary symptoms due to the mass compression or invasion of the surrounding tissues and organs. Surgical resection is the first choice for treating presacral tumors. Clinicians should choose surgical procedures based on the location and size of the tumors. We presented a 43-year-old woman who suffered from pelvic pain and primary infertility from two years ago. A large mass between the posterior vaginal wall and the rectum was found on recto-vaginal examination. Magnetic resonance imaging (MRI) revealed a large 120×115 mm benign multiloculated cystic mass. Eventually, the mass was removed through laparoscopic surgery. The pathology report indicated a carcinoid tumor (grade I) with no lymphovascular invasion. Thus, presacral tumors are resectable through laparoscopy with lower complications than open surgery.

Congenital Sacrococcygeal Neuroblastoma: A Report of Two Cases with Summary of Prior Published Cases

BackgroundNeuroblastoma can arise from extra-adrenal sites in the paraspinal sympathetic chain, including the presacral region, where they must be differentiated from an immature or malignant neural lesion arising from a teratoma.Case ReportWe describe two congenital presacral neuroblastomas. The main clinical differential diagnoses were sacrococcygeal teratoma and meningomyelocele. Pathologically, they lacked teratomatous tissues, lacked germ cell serum markers, were localized without metastases, and were MYCN non-amplified. Both patients have done well without chemotherapy at 18 and 15 months of follow-up.ConclusionCongenital presacral neuroblastoma should be differentiated from teratomatous lesions, and in general have a good prognosis.

Fat-containing pelvic lesions in females

Pelvic tumors are common in females and have a broad differential diagnosis. The clinical management of pelvic tumors varies widely-from observation to surgical resection-and imaging plays a pivotal role in diagnosis and clinical decision-making in these cases. In particular, imaging can help determine the organ of origin and tissue content of these tumors, which are the most important steps to narrowing the differential diagnosis. Fat has a characteristic appearance and is often easily identified on ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI). The amount and distribution of intralesional fat varies in different types of tumors. Macroscopic intralesional fat is often easily recognized by its hyperechoic appearance on US and low attenuation on CT similar to subcutaneous fat. On MRI, macroscopic fat is hyperintense on T1-weighted (T1W) images, with characteristic signal loss on fat-saturated sequences and India-ink artifact on opposed-phase T1W images. Macroscopic fat is the hallmark of teratomas, which are the most common ovarian neoplasms. Uterine lipoleiomyomas, peritoneal loose bodies, intraperitoneal and extraperitoneal primary lipomatous tumors such as lipoma and liposarcomas, and extra-adrenal myelolipomas are other pelvic masses distinguished by the presence of macroscopic fat. However, the imaging diagnosis of pelvic masses containing minimal or microscopic fat, such as immature ovarian teratomas, steroid cell ovarian neoplasms, and extramedullary hematopoiesis, can present a diagnostic challenge owing to their nonspecific appearance on US or CT. Obtaining MRI with in-phase and opposed-phase dual-echo T1W sequences and depicting chemical shift artifacts can be helpful in distinguishing these lesions.

Clinical manifestations, classification, and surgical management of sacral tumors and the need for personalized approach to sacrectomy

Background:

Although comprising 7% of all spinal tumors, sacral tumors present with a litany of issues due to their slow growth and difficulty in detection. As a result, sacral tumors can grow unperturbed for years until a patient presents for an incidental workup of an unassociated minor trauma or an offending primary tumor source that has metastasized to the sacrum; in most cases, this includes primary tumors of the breast, prostate, and lung. The goal of this review is to outline the pathophysiology underlying sacral tumors including the various tissues and structures that can be targeted for treatment, along with a discussion of the surgical approach to sacrectomy.

Methods:

An extensive review of the published literature was conducted through PubMed database with articles simultaneously containing both search terms “sacral tumors” and “sacrectomy.” No date restrictions were used.

Results:

The search yielded 245 related articles. Cross-checking of articles was conducted to exclude of duplicate articles. The articles were screened for their full text and English language availability. We finalized those articles pertaining to the topic.

Conclusion:

Once a sacral tumor has reached the point of diagnostic detection, invasive sacrectomy is typically utilized (through an anterior, posterior, or combination approach) to locally isolate and resect the tumor and minimize risk of future tumor growth and additional bone loss. While institutions have varying criteria for surgical approaches, a combination of anterior and posterior approach has traditionally been used in total and high sacrectomies due to the control it provides surgeons toward the rectum and vasculature anterior to the sacrum. A posterior-only approach can be performed for tumors that failed to invade pelvic organs or extend past the lumbosacral junction. Early detection with screenings can help avoid invasive sacrectomy by identifying the onset of tumor formation in the sacrum, particularly for highly metastatic cancers.

Laparoscopic resection of a neuroendocrine tumor that almost fully replaced tailgut cysts: a case report

Background

Neuroendocrine tumors (NETs) originate from neuroendocrine cells, which are found throughout the body. NETs occur principally in the gastrointestinal tract (approximately 65%) and bronchopulmonary tract (approximately 25%) but rarely occur in the presacral space. Aside from primary and metastatic lesions, there have been reports of NETs occurring in the presacral space arising from tailgut cysts, teratomas, and imperforate anus. We herein report a rare case of laparoscopic resection of a NET in the presacral space, which almost fully replaced tailgut cysts.

Case presentation

A 68-year-old woman was referred to our hospital for surgery of a right inguinal hernia, but preoperative computed tomography revealed an asymptomatic 43-mm mass in the presacral space. Magnetic resonance imaging showed a multilocular solid mass with clear boundaries and a slightly high signal intensity on T1- and T2-weighted images. Positron emission tomography showed 18F-fluorodeoxyglucose uptake. Thus, we suspected a malignant tumor and performed laparoscopic resection to obtain a definitive diagnosis. Macroscopically, the tumor was 43 mm in size with clear boundaries, and the cut surface was a gray-white solid component. Histopathological findings revealed that the tumor was composed of relatively uniform cells with fine chromatin, with round to oval nuclei arranged in solid, trabecular, or rosette-like growth patterns. Small cysts lined with stratified squamous epithelium and columnar epithelium were observed along with solid components of the tumor, which is a feature of tailgut cysts. Therefore, the final diagnosis was NET Grade 1 arising from tailgut cysts. No recurrence was observed within 1 year after surgery.

Conclusions

We performed en bloc laparoscopic resection of a NET arising from tailgut cysts in the presacral space without injury. In cases of a solid lesion in the presacral space, not only the primary disease but also the pathological condition with tissue transformation and replacement should be considered, as in this case.

Sacrococcygeal Teratoma: A Case Report

Sacrococcygeal teratoma is rare and happens in 1:35,000 to 40,000 live births. It is more common in girls than boys with the reported ratio of 3:1 to 4:1. We herein report an unusual case of a huge sacrococcygeal teratoma, which was more than half of the size and weight of the baby which was terminated at 24 weeks of gestation.

Avascular Spaces of the Female Pelvis-Clinical Applications in Obstetrics and Gynecology

The term "spaces" refers to the areas delimited by at least two independent fasciae and filled with areolar connective tissue. However, there is discrepancy regarding the spaces and their limits between clinical anatomy and gynecologic surgery, as not every avascular space described in literature is delimited by at least two fasciae. Moreover, new spaces and surgical planes have been developed after the adoption of laparoscopy and nerve-sparing gynecological procedures. Avascular spaces are useful anatomical landmarks in retroperitoneal anatomic and pelvic surgery for both malignant and benign conditions. A noteworthy fact is that for various gynecological diseases, there are different approaches to the avascular spaces of the female pelvis. This is a significant difference, which is best demonstrated by dissection of these spaces for gynecological, urogynecological, and oncogynecological operations. Thorough knowledge regarding pelvic anatomy of these spaces is vital to minimize morbidity and mortality. In this article, we defined nine avascular female pelvic spaces-their boundaries, different approaches, attention during dissection, and applications in obstetrics and gynecology. We described the fourth space and separate the paravesical and pararectal space, as nerve-sparing gynecological procedures request a precise understanding of retroperitoneal spaces.

A rare case of pelvic bronchogenic cyst treated by laparoscopic surgery

A 31-year-old man with pain in his thigh was diagnosed with a benign presacral cystic mass. We performed laparoscopic subtotal resection of the cyst utilizing mobilization of a total mesorectal excision procedure used in low anterior resection for rectal cancer. Histopathological findings showed that the cystic lumen of the specimen was lined with pseudostratified columnar ciliated epithelium and had glandular structures and smooth muscle in its wall, leading to a diagnosis of bronchogenic cyst. The postoperative course was uneventful, and as of 6 months after surgery, the patient was doing well with no evidence of recurrence.

Adult sacrococcygeal teratoma: a retrospective study over eight years at a single institution

OBJECTIVE

To determine the clinical, imaging, and histological features, and surgical resection modalities and outcomes of adult sacrococcygeal teratoma (SCT).

METHODS

Adult patients with histopathologically diagnosed SCT were enrolled in our hospital between August 2010 and August 2018. Each patient's characteristics and clinical information were reviewed.

RESULTS

There were 8 patients in the study (2 males, 6 females) with a median age of 34 years (range, 18-67 years). The time to clinical symptoms was 14 d to 35 years, with a median time of 4 years. Six patients presented with symptoms of sacrococcygeal pain, and four with signs of sacrococcygeal mass and ulceration in the sacrococcygeal region. Six patients were evaluated using a combination of computed tomography (CT) and magnetic resonance imaging (MRI). All patients showed a presacral tumor with heterogeneous intensity on CT images. All patients underwent surgical treatment, including 6 parasacral, 1 transabdominal, and 1 combined anterior-posterior surgery cases. Seven patients were histopathologically diagnosed with benign mature SCT, and have shown no recurrence. One patient had malignant SCT, with recurrence at 84 months after surgery. After a second surgery, the patient had no recurrence within 6 months follow-up after re-resection.

CONCLUSIONS

Our retrospective study demonstrated: (1) adult SCT is difficult to diagnose because of a lack of typical clinical symptoms and signs; (2) a combination of CT and MRI examination is beneficial for preoperative diagnosis; (3) the choice of surgical approach and surgical resection modality depends on the size, location, and components of the tumor, which can be defined from preoperative CT and MRI evaluation; (4) most adult SCTs are benign; the surgical outcome for the malignant SCT patient was good after complete resection. Even for the patient with recurrent malignant SCT, the surgical outcome was good after re-resection.

Nongynecologic Findings Seen at Pelvic US

Ultrasonography (US) is frequently the first imaging modality used to examine women with symptoms involving the pelvis. It is widely available and involves no exposure to ionizing radiation. Images can be acquired with a transabdominal, endovaginal, or translabial approach, and the use of video clips and three-dimensional reconstructions can be helpful. US is excellent for assessment of the uterus, ovaries, and adnexa. Occasionally, nongynecologic pelvic diseases arising from the gastrointestinal, genitourinary, and musculoskeletal systems and the pelvic peritoneal and extraperitoneal spaces may be detected and can be a source of diagnostic dilemma. US can be helpful not only in the detection but also occasionally in the characterization of such entities. Computed tomography and magnetic resonance imaging are useful in complicated cases. In this article, the normal US appearance of the bowel and US signs of bowel disease and specific entities, including appendicitis, diverticular disease, bowel obstruction, appendiceal mucocele, and intestinal tumors, are reviewed. The lower urinary tract is included in the field of view in every pelvic US examination; commonly encountered entities related to the urinary bladder, distal ureter, and urethra are illustrated. In addition to arising in the gastrointestinal and genitourinary tracts, pathologic conditions in the pelvis can arise in the peritoneal or extraperitoneal space. Although conditions of the pelvic peritoneal and extraperitoneal spaces are rare, it is important to recognize these entities and distinguish them from the more common gynecologic diseases. Owing to the implications for diagnosis and management, radiologists and other physicians who perform pelvic US should be aware of the spectrum of nongynecologic pathologic entities that can be detected. ©RSNA, 2017.

Adnexal masses or perineural (tarlov) cysts? Differentiation by imaging techniques: A case report

BACKGROUND

Perineural cysts formed within the nerve-root sheath at the dorsal root ganglion. They are most commonly located in the arachnoid covering the junction of the dorsal ganglion and nerve root. They are usually asymptomatic, incidental findings, usually located in the lumbar and sacral region of the spinal canal. It is important to consolidate the imaging findings of this rare disease so clinicians can become more clinically relevant in the evaluation of these cysts.

CASE

Herein we report a case of perineural cyst misdiagnosed with hydrosalpinx by pelvic ultrasonography and finally diagnosed with magnetic resonance image.

CONCLUSION

Perineural cyst should be considered, in the presence of bilateral adnexal masses separated from the ovaries in pelvic sonography.

Primary Cystic Lesions of the Retrorectal Space: MRI Evaluation and Clinical Assessment

OBJECTIVE

The purpose of this study was to assess the a priori chance that primary cystic lesions of the retrorectal space are malignant and to investigate MRI characteristics that indicate malignancy.

MATERIALS AND METHODS

Patients referred to a center for colorectal surgery were recruited from 2000 to 2014. Lesions were proven by clinical assessment and histopathology. MRI was performed at 1.5 T with examinations evaluated by two radiologists. Interobserver agreement was assessed (Cohen kappa) and differences between malignant and benign lesions calculated (Fisher exact test).

RESULTS

Twenty-eight patients (22 women, six men; age range, 18-70 years) with 31 lesions were included. Lesions were categorized as tailgut cysts (n = 16, 52%), teratomas (n = 9, 29%), lesions of colorectal origin (n = 4, 13%), or neurogenic lesions (n = 2, 6%). Five patients (18%) had malignant lesions. Colorectal lesions had the highest percentage of malignancy (3/4, 75%). A solid tissue component was found in all five (100%) malignant lesions and two (8%) of the benign lesions, which were both teratomas (p < 0.05). Sensitivity and specificity for malignancy according to the presence of a solid tissue component was 100% (5/5) and 92% (24/26). For unilocularity, multilocularity, debris, septa, and wall thickening, differences were not significant. Interobserver agreement was excellent (κ = 1) for all characteristics except debris (κ = 0.795).

CONCLUSION

The majority of retrorectal cystic lesions are benign. The presence of a solid tissue component should raise suspicion for malignancy.