Magnetic resonance imaging of pediatric pelvic masses

Challenges in the diagnosis and treatment of pure non-gestational uterine choriocarcinoma in a child: a case report

BACKGROUND

Diagnosing non-gestational uterine choriocarcinoma in children is challenging because of its rarity and nonspecific imaging findings. Herein, we report a case of non-gestational uterine choriocarcinoma in a child, which was unexpectedly found during exploratory laparotomy and confirmed by histopathological findings. However, the tumor did not respond to chemotherapy.

CASE PRESENTATION

A 4-year-old Indonesian female patient was brought into the emergency unit with chief complaint of vaginal bleeding. She had suffered from vaginal spotting 4 months before being admitted to the hospital. Physical examination revealed a distended abdomen in the left lumbar region and a palpable fixed mass with a smooth surface. Abdominal computed tomography scans revealed a large mass (10 × 6 × 12 cm) with fluid density and calcification. Thus, we suspected left ovarian teratoma. The patient's luteinizing hormone, follicle-stimulating hormone, and lactate dehydrogenase levels were 25.2 mIU/ml, 0.1 mIU/ml, and 406 U/l, respectively. According to the clinical and radiological findings, we decided to perform an exploratory laparotomy and found a tumor originating from the uterus, not the ovarium. We did not observe liver nodules and any enlargement of abdominal lymph nodes. Subsequently, we performed hysterectomy. The histopathological findings supported the diagnosis of choriocarcinoma. The patient was discharged uneventfully on postoperative day 5. Thereafter, the patient underwent nine cycles of chemotherapy, including carboplatin (600 mg/m2 IV), etoposide (120 mg/m2 IV), and bleomycin (15 mg/m2 IV). However, on the basis of the clinical findings of a palpable mass and partial intestinal obstruction, the tumor relapsed soon after the ninth cycle of chemotherapy. Currently, the patient is undergoing chemotherapy again.

CONCLUSIONS

Although pure non-gestational uterine choriocarcinoma is rare, it should be considered as one of the differential diagnoses for intraabdominal tumors in a child, so as to better guide and counsel families regarding the surgical plan and prognosis, respectively. In the present case, the patient's response to chemotherapy was poor, implying that the treatment of non-gestational choriocarcinoma is still challenging, particularly in the pediatric population.

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.

1.5 vs 3 Tesla Magnetic Resonance Imaging: A Review of Favorite Clinical Applications for Both Field Strengths-Part 2

ABSTRACT

The second part of this review deals with experiences in neuroradiological and pediatric examinations using modern magnetic resonance imaging systems with 1.5 T and 3 T, with special attention paid to experiences in pediatric cardiac imaging. In addition, whole-body examinations, which are widely used for diagnostic purposes in systemic diseases, are compared with respect to the image quality obtained in different body parts at both field strengths. A systematic overview of the technical differences at 1.5 T and 3 T has been presented in part 1 of this review, as well as several organ-based magnetic resonance imaging applications including musculoskeletal imaging, abdominal imaging, and prostate diagnostics.

Imaging of Soft Tissue Tumors

Differentiation of malignant from benign soft tissue tumors is challenging with imaging alone, including that by magnetic resonance imaging and computed tomography. However, the accuracy of this differentiation has increased owing to the development of novel imaging technology. Detailed patient history and physical examination remain essential for differentiation between benign and malignant soft tissue tumors. Moreover, measurement only of tumor size based on Response Evaluation Criteria In Solid Tumors criteria is insufficient for the evaluation of response to chemotherapy or radiotherapy. Change in metabolic activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography or dynamic contrast enhanced-derived quantitative endpoints can more accurately evaluate treatment response compared to change in tumor size. Magnetic resonance imaging can accurately evaluate essential factors in surgical planning such as vascular or bone invasion and "tail sign". Thus, imaging plays a critical role in the diagnosis and treatment of soft tissue tumors.

MR imaging in discriminating between benign and malignant paediatric ovarian masses: a systematic review

OBJECTIVES

The use of magnetic resonance (MR) imaging in differentiation between benign and malignant adnexal masses in children and adolescents might be of great value in the diagnostic workup of sonographically indeterminate masses, since preserving fertility is of particular importance in this population. This systematic review evaluates the diagnostic value of MR imaging in children with an ovarian mass.

METHODS

The review was made according to the PRISMA Statement. PubMed and EMBASE were systematically searched for studies on the use of MR imaging in differential diagnosis of ovarian masses in both adult women and children from 2008 to 2018.

RESULTS

Sixteen paediatric and 18 adult studies were included. In the included studies, MR imaging has shown good diagnostic performance in differentiating between benign and malignant ovarian masses. MR imaging techniques including diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging seem to further improve the diagnostic performance.

CONCLUSION

The addition of DWI with apparent diffusion coefficient (ADC) values measured in enhancing components of solid lesions and DCE imaging may further increase the good diagnostic performance of MR imaging in the pre-operative differentiation between benign and malignant ovarian masses by increasing specificity. Prospective age-specific studies are needed to confirm the high diagnostic performance of MR imaging in children and adolescents with a sonographically indeterminate ovarian mass.

KEY POINTS

• MR imaging, based on several morphological features, is of good diagnostic performance in differentiating between benign and malignant ovarian masses. Sensitivity and specificity varied between 84.8 to 100% and 20.0 to 98.4%, respectively. • MR imaging techniques like diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging seem to improve the diagnostic performance. • Specific studies in children and adolescents with ovarian masses are required to confirm the suggested increased diagnostic performance of DWI and DCE in this population.

Ultrasonographic and multimodal imaging of pediatric genital female diseases

Ultrasonography is the first-line imaging modality in the evaluation of the female pelvis in childhood and adolescence, because it is easy to perform, non-invasive and it does not require sedation. The transabdominal approach is preferred in children and adolescents, after filling the bladder to move away the bowel loops from the pelvis. The probe frequency must be adapted to age, thickness of tissues and depth of the structures under examination. High-frequency (4-12 MHz) linear or convex probes are used in newborns; high-frequency linear probes (4-12 MHz) in toddler, convex 5-7.5 MHz probes in girls and convex 3.5-5 MHz probes in teenagers. In this article, the main pathological conditions of the genital female tract in pediatric age are examined, such as congenital anomalies, disorders of sex development, ovarian cysts, ovarian tumors, adnexal torsion, primary amenorrhea, precocious puberty and pelvic inflammatory disease.

What MRI can tell us about neurogenic tumors and rhabdomyosarcoma

This review focuses on the MRI features of neurogenic tumors and rhabdomyosarcoma in children. Neurogenic tumors include those arising from a nerve sheath and neuroblastic tumors that arise from the sympathetic nervous system. Nerve sheath tumors can be benign or malignant and occur sporadically or in association with neurofibromatosis type 1. Neuroblastic tumors comprise a spectrum of tumors ranging from highly malignant neuroblastoma to the benign ganglioneuroma. These neurogenic tumors arise in typical locations within the chest, abdomen and pelvis and have distinctive and characteristic imaging features that should suggest their diagnosis. Rhabdomyosarcoma encompasses a variety of histological subtypes that exhibit varying degrees of aggressiveness and biological behavior. While some abdominal and pelvic locations are well known to give rise to rhabdomyosarcoma, this tumor can arise in any tissue in the body except bone. The paper reviews the MRI and clinical features of neurogenic tumors and rhabdomyosarcoma and the imaging findings that can aid in clinical management.

Renal Remnant Presenting as a Large Retroperitoneal Mass in a Teenage Girl

BACKGROUND

Adolescents commonly present with a symptomatic pelvic mass. The vast majority of these masses are benign and gynecological in nature. Nonetheless, it is important to consider less common etiologies including retroperitoneal and enteric cysts.

CASE

A 17-year-old female patient with chronic pelvic pain due to a large 9-cm cystic pelvic mass underwent laparoscopy. Operative findings indicated a retroperitoneal mass, which was excised in a minimally invasive fashion. Final pathology was suggestive of a remnant of a developmental renal anomaly.

SUMMARY AND CONCLUSION

This case highlights the importance of a broad differential when considering etiologies of a cystic pelvic mass. Clinical diagnosis and management are often challenging. Therefore, it is important to increase awareness of this diagnosis within the gynecological community.