Retroperitoneal teratomas in children

Malignant transformation of a mature retroperitoneal teratoma into adenocarcinoma

Retroperitoneal mature teratoma is a rare congenital tumor, far behind ovarian and testicular localizations. Malignant transformation of teratomas is extremely uncommon. We report a case of a 23-year-old female, who presented with chronic pelvic heaviness, abdominopelvic ultrasound revealed a cystic mass in the right iliac fossa, initially considered as a functional ovarian cyst. Given the persistence of the patient's symptoms a pelvic MRI was requested. It showed a right retro-colic cystic unilocular with parietal nodule. The two ovaries showed normal appearance. A retroperitoneal teratoma was suggested given the retroperitoneal topography of the mass, and the presence of a tissular parietal nodule. She underwent surgery and the diagnosis was confirmed after histological study

Ultrasound and alternative multimodality imaging of intra-abdominal and pelvic cystic masses in the newborn

Introduction: Ultrasound is used commonly to detect and diagnose intra-abdominal and pelvic cystic masses in the newborn as it is easily available, relatively low cost, and non-invasive. Discussion: The diagnosis can be made or narrowed down by determining the location, size, sonographic features, organ involvement, and internal vascularity. The differential diagnoses include hydronephrosis, multicystic dysplastic kidney, adrenal haemorrhage, cystic teratomas, ovarian cysts, enteric cysts, meconium cysts, and liver haemangiomas. With the appropriate radiological knowledge, the ultrasound practitioner can help obtain an accurate diagnosis. Conclusion: This pictorial essay will familiarise the reader with the different common causes of intra-abdominal and pelvic masses detected on ultrasound through a wide range of conditions. The role of ultrasound in the evaluation of these conditions will be discussed and alternative imaging correlates will be offered.

Retroperitoneal teratomas in children: a single institution experience

PURPOSE

Retroperitoneal teratomas (RPTs) are rare in infants. We report our experience of treating pediatric patients with RPTs over many years at a single institution, with the aim of developing a safe and secure operative strategy for RPTs in infants.

METHODS

We reviewed the medical records of patients who underwent treatment for RPTs in our institution between April, 1984 and December, 2017, to analyze their background and clinical data. The diagnosis of RPT was confirmed histologically in all patients.

RESULTS

The subjects of this retrospective analysis were 14 pediatric patients (female, n = 11; male, n = 4), ranging in age from 6 days to 12 years, 11 (73.3%) of whom were under 1 year of age. Complete surgical resection was performed in all patients. The tumor ruptured during surgery in four (26.7%) patients and perioperative vessel injuries occurred in six (40.0%) patients, resulting in nephrectomy in one (6.7%). Three (20.0%) patients suffered unilateral renal dysfunction as a surgical complication. Only one patient received postoperative chemotherapy. All patients were free of disease at the time of writing.

CONCLUSION

Perioperative complications are not uncommon during surgery for RPTs, despite their benign nature. Preoperative imaging evaluation is important and operative management may be challenging. Because of the favorable prognosis and the frequency of adverse events in surgery, partial resection or split excision is sometimes unavoidable. Meticulous follow-up for recurrence is required for such patients.

Factors Associated With Perioperative Complications in the Treatment of Pediatric Retroperitoneal Teratoma

BACKGROUND

Perioperative complications are common during the surgical treatment of pediatric retroperitoneal teratoma (RPT). Some clinical and radiographic features could be associated with perioperative complications. This study was designed to identify the factors associated with such complications.

MATERIALS AND METHODS

We retrospectively analyzed the clinical data of RPT patients who underwent surgical treatment at the Department of Pediatric Surgery of The Affiliated Hospital of Qingdao University between January 2008 and January 2020, including demographics, imaging data, intraoperative findings, perioperative complications, pathological data, and outcomes.

RESULTS

A total of 91 patients were included in this study, including 30 boys and 61 girls. Of these, 71 patients (78%) were 1 y old or younger. Thirty-eight patients (41%) had perioperative complications (44 intraoperative and 7 postoperative). Preoperative imaging studies showed that the tumor distorted adjacent arteries, veins, and organs in all patients. More veins and organs were displaced and distorted by the tumor in patients who had perioperative complications. Multivariate analysis showed that the number of organs compressed and distorted by the tumor was significantly related to perioperative complications (odds ratio 1.69, 95% confidence interval 1.19-2.41).

CONCLUSIONS

Surgical treatment of RPT is complex and challenging. As majority are benign, a complete excision is usually curative. The number of organs compressed and distorted by the tumor is positively related to perioperative complications.

Mature Cystic Teratoma of Renal Pelvis: An Unusual Presentation at an Uncommon Site

Teratoma of the kidney is uncommon. We report a case of a young boy with a large, right-sided retroperitoneal cyst suspected as lymphangioma causing hydronephrosis. His renal pelvis was dilated, containing purulent fluid, and a nephrectomy was performed. Histopathology revealed a mature cystic teratoma of the renal pelvis.

Surgical risk factors of retroperitoneal teratoma resection in children

BACKGROUND

Retroperitoneal teratoma is uncommon and carries considerable surgical risks. Some preoperative clinical and radiographic features could be predictive of surgical complication risk. We aimed to identify surgical risk factors that predicted perioperative complications.

METHODS

Childhood retroperitoneal teratoma cases operated on at Guangzhou Women and Children's Medical Center were retrospectively reviewed. Demographic features; clinical, laboratory, radiographic, and intraoperative findings; perioperative complications; and pathology results were assessed.

RESULTS

Between May 2000 and December 2017, 152 childhood retroperitoneal teratomas were resected from 102 female patients (median age 5.75 months). Sixty-three patients (41%) experienced perioperative complications (79 intraoperative and 5 postoperative), including kidney excision (4 patients) and adrenal gland excision (1 patient). Among 113 patients with preoperative computed tomography/magnetic resonance images, 112 (99%), 111 (98%), and 113 (100%) demonstrated artery, vein, and organ distortion, respectively, and 28 (25%) had vessels encased by tumors. Patients with perioperative complications had more veins and organs distorted by tumors. In multivariate analysis, the numbers of vessels encased and organs distorted by tumors were significantly associated with perioperative complications (odds ratio = 1.45 and 1.69, 95% confidence interval: 1.00-2.10 and 1.19-2.41, respectively).

CONCLUSIONS

Retroperitoneal teratoma resection has a high perioperative complication rate. Teratomas encompassing the vasculature and distorting organs were associated with increased surgical risk. Additional studies aiming to better define the surgical approach to retroperitoneal teratoma are warranted.

LEVELS OF EVIDENCE

III.

Retroperitoneal Mature Cystic Teratoma in a 3-month-old Infant: A Case Report and Literature Review

Retroperitoneal teratoma (RPT) is an exceedingly rare neoplasm in infancy. We came across a 3-month-old infant with large RPT in the left suprarenal area. The tumor was completely excised, and the patient was successfully discharged. Histopathological examination suggested the diagnosis of mature cystic teratoma.

Excision of retroperitoneal germ cell tumor in children: A distinct surgical challenge

PURPOSE

The excision of retroperitoneal germ cell tumor (GCT) is a surgical challenge compounded by the absence of definite surgical guidelines. The aim of this study is to present the surgical difficulties and morbidity associated with resection of these tumors.

METHODS

Fifteen patients (7 males and 8 females) undergoing excision of retroperitoneal GCT between February 2008 and February 2016 were evaluated.

RESULTS

Except for an adolescent, the majority of patients were infants (median age: 4months). The surgical excision entailed extensive vascular dissection in all patients with associated significant blood loss in two, adjacent organ removal in five, and vessel repair in one patient. The resection was complete in all except two patients. Both the patients with incomplete resections had immature teratoma and received postoperative chemotherapy. At a median follow-up of 53months, 13 patients are alive and disease free, one patient is alive with stable disease, and one patient had died owing to respiratory complications. There were no local recurrences in the patients with complete excision.

CONCLUSION

Although the outcomes are excellent after surgery, resection of retroperitoneal GCT is a distinct surgical challenge. The surgical difficulties emanate from the need for extensive vascular dissection and risk to adjacent structures.

LEVEL IV EVIDENCE

Therapeutic study.

Primary renal teratoma: a rare entity

Teratomas are neoplasms that arise from pluripotent cells and can differentiate along one or more embryonic germ lines. Renal teratoma is an exceedingly rare condition. Teratomas commonly arise in the gonads, sacrococcygeal region, pineal gland, and retroperitoneum. They present mainly as an abdominal mass with few other symptoms. Majority of the tumors are benign, situated on the left side and para renal, occasional lesions are bilateral. If diagnosed early, they are amenable to curative excision.Renal teratomas are rare and most have been dismissed as cases of teratoid nephroblastomas or retroperitoneal teratomas secondarily invading the kidney. The differentiation between these two neoplasms in the kidney is often problematic.We present a case of intrarenal immature teratoma in a six-month-old baby girl.

VIRTUAL SLIDES

The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1746249869599954.

Teratomas: a multimodality review

Germ cell tumors (GCTs) may occur in both children and adults and include a broad array of histologic subtypes, such as teratoma, seminoma (known as dysgerminoma in the ovary and germinoma in the pineal gland), choriocarcinoma, yolk sac tumor, embryonal cell carcinoma, and mixed GCT. In adults, GCTs occur most commonly in the gonads. In children, sacrococcygeal tumors predominate. Teratomas are a common form of GCT. They are defined histologically as containing tissues derived from all 3 germ cell layers: ectoderm, mesoderm (most teratomas contain fat, an imaging hallmark, which is a mesodermal derivative), and endoderm. Teratomas are also classified as mature or immature, depending on the degree of differentiation of its components, and in adults, immature tumors are more likely to exhibit malignant behavior.

Elective suprarenal and infrarenal cavectomy for excision of giant retroperitoneal teratoma in infancy

Retroperitoneal teratomas are rare, often massive tumors usually presenting in infancy; being mostly mature lesions, their treatment is surgical but may represent a formidable challenge. Major vessel displacement may not be well demonstrated on imaging: vascular injuries are well-recognized surgical complications with urgent repair, ligation, or even segmental excision of major vessels being required. However, the literature provides few suggestions to avoid these problems. In our approach, we assessed the important effaced abdominal veins on imaging and at laparotomy to allow us to electively excise the suprarenal and infrarenal vena cava (with both renal vein ostia) and thereby resect a giant retroperitoneal teratoma without inadvertent vessel injury, major bleeding, renal disturbance, or tumor recurrence. Described for renal tumors, elective cavectomy has not been reported as a technique to manage primary retroperitoneal teratomas. In selected cases, with careful preservation of renal venous collaterals, we show this can be a well-tolerated, preemptive option to reduce the high risks of surgical complications.

Retroperitoneal neoplasms within the perirenal space in infants and children: differentiation of renal and non-renal origin in enhanced CT images

PURPOSE

To retrospectively demonstrate the specific CT findings of retroperitoneal neoplasms to diagnosis and differential diagnosis renal and non-renal tumors within the perirenal space in infants and children.

MATERIALS AND METHODS

We retrospectively reviewed the clinical data and CT images of 42 consecutive patients with surgically and pathologically proven retroperitoneal neoplasms within the perirenal space. The patients were divided into renal tumors group (n=16) and non-renal tumors group (n=26). The former included nephroblastoma (n=15) and renal lymphoma (n=1), while the latter included neuroblastoma (n=12), retroperitoneal teratoma (n=6), adrenal ganglioneuroma (n=4), retroperitoneal lymphoma (n=2), ectopic pheochromocytoma (n=1) and adrenal cortical carcinoma (n=1). The clinical information of these patients and the major CT imaging findings which were related to lesion localization in the two groups were compared and statistically analyzed using Pearson Chi-Square Test and Risk Estimate.

RESULTS

The mean diameter of tumors was 9.82±6.13 cm (n=42 range: 2.3-3 2cm). The demographic data and chief clinical symptoms between the renal tumor group and the non-renal tumor group showed no statistically significant differences (P>0.05). 30.8% (8/26) of non-renal tumor patients presented elevated urinary vanillylmandelic acid (VMA) level, while no patient showed elevated VMA in renal tumor group (P<0.05). Some CT imaging signs of the renal tumors including "crescent sign" (odds ratio, OR=52), "beak sign" (OR=84), "embedded organ sign" (OR=84), and "prominent feeding artery sign" (OR=36) showed significantly higher incidence when compared to the non-renal tumors (P<0.001). The sign of "renal displacement and renal axis rotation" (OR=0.059) was seen in 23 of 26 (88.5%) non-renal tumors, but in only 5 of 16 (31.3%) renal tumors (P<0.001). The sign of "extra-renal central plane of tumor" (OR=0.038) was displayed in 24 of 26 (92.3%) non-renal tumors, but in only 5 of 16 (31.3%) renal tumors (P<0.001). The CT findings such as "pseudocapsule" (OR=38.5), "necrosis and cystic change" (OR=11.2), "vascularity" (OR=16.867), "distant metastasis" (OR=5.96), and "inferior vena cava tumor thrombus" which were thought to be characteristic of renal tumors were observed with significant higher incidence in renal tumors group than in the non-renal tumors group (P<0.05); while CT signs of "irregular mass" (OR=0.045) and "intratumoral calcifications" (OR=0.065) were observed with lower incidence in renal tumors group than in the non-renal tumors group (P<0.05).

CONCLUSION

The "crescent sign", "beak sign", "embedded kidney sign" and "renal arteries feeding" are the most specific CT signs suggestive of renal tumors and distinguish them from non-renal origin tumors within the perirenal space. Other CT signs, such as "pseudocapsule", "hypervascular tumors" and "Inferior vena cava tumor thrombus", when present, tumors of renal origin are strongly suggested. On the other hand, CT signs of "irregular mass", "intratumoral calcifications", and associated elevated urinary vanillylmandelic acid strongly suggest the non-renal tumors.

Upper abdominal teratomas in infants: radiological findings and importance of the vascular anatomy

BACKGROUND

Primary upper abdominal teratomas are extremely rare tumours, most commonly arising in infants. The radiological literature relating to them is sparse. Surgical resection is difficult due to distortion of the vascular anatomy.

OBJECTIVE

To reassess the value of preoperative imaging with specific reference to the presence/absence of typical features of teratoma, anatomical location and adjacent vascular anatomy.

MATERIALS AND METHODS

The histopathology database was used to identify infants with upper abdominal teratoma. Pathological, surgical and radiological data were reviewed.

RESULTS

The search of the database identified 12 infants (10 girls, 2 boys) with an abdominal/retroperitoneal teratoma during the period 1993 to 2006. All teratomas were benign. In the majority of infants, typical radiological features of teratoma were demonstrated (fat, calcium). Identification of the major abdominal vessels on CT scan (most commonly the inferior vena cava) was not possible in all infants. Distortion (and commonly encasement) of the adjacent major abdominal vessels was usually evident.

CONCLUSION

Upper abdominal teratomas in infants have typical radiological features. Preoperative delineation of the major vascular anatomy is often imprecise. Significant distortion of vascular anatomy was present in all infants and awareness of this feature impacts on surgical planning.

Retroperitoneal teratomas--potential for surgical misadventure

BACKGROUND

Retroperitoneal teratoma (RPT) is a relatively uncommon tumor in children. This study concerns 6 children with RPT that involved surrounding structures and required rather extensive operative procedures to successfully excise the lesions.

METHODS

A review of RPT in children encountered at a single institution over an 8-year period by a single surgeon was carried out. Age at presentation, sex, operative findings, surgical management, and outcomes were evaluated.

RESULTS

Four of the 6 patients were girls, and 5 were younger than 6 months at diagnosis. All of the tumors enveloped and displaced the aorta and vena cava, 1 involved the stomach wall, 2 others displaced the renal vessels, and 1 the portal vein. Extensive resection including major vessel ligation was necessary for complete excision. All the tumors were benign, but 1 recurred. There were no deaths; however, 2 children have persistent hypertension.

CONCLUSIONS

The operative management of RPTs may be complex and challenging. Despite their benign nature, the lesions can attenuate and surround major vessels, making resection difficult. Ligation of major vessels when necessary is tolerated well and may be required for complete tumor excision.

Retroperitoneal teratoma presenting as an abscess in childhood

Retroperitoneal teratomas are rare, representing only 1% to 11% of primary retroperitoneal neoplasms. They typically present as an asymptomatic abdominal mass but can grow to enormous size. This case describes a patient who initially presented in childhood with an acute abdomen because of an abdominal abscess that was treated with surgical drainage and antibiotics. Fifteen years later, the patient had a recurrence of symptoms and the abscess was ultimately recognized to be an infected retroperitoneal teratoma. There have been reports of intraabdominal and pelvic teratomas presenting as abscesses in adults. However, to our knowledge, there has been no prior description of this phenomenon in children. In an otherwise healthy child who presents with an unexplained abscess in the sacrococcygeal area, gonads, mediastinum, or retroperitoneum, one should entertain the diagnosis of teratoma.