An unusual case of congenital primitive neuroectodermal tumor with ocular metastasis

Congenital soft tissue Ewing's sarcoma: A case report of pre- and postnatal magnetic resonance imaging findings

RATIONALE

Most congenital soft tissue masses are benign. Ewing's sarcoma (ES) is a highly malignant tumor that commonly occurs in children and adolescents and rarely occurs during the fetal period. Cases of congenital soft tissue ES with magnetic resonance imaging (MRI) findings are scarce. To the best of our knowledge, no previous reports have described the pre- and postnatal MRI findings of ES.

PATIENT CONCERNS

We present a case of congenital soft tissue ES arising in the body wall, which was examined using MRI during the prenatal and neonatal periods.

DIAGNOSES

Malignancy was suspected by diffusion-weighted imaging, which demonstrated restricted diffusion within the mass even during the fetal period. ES was confirmed via histopathological examination after birth.

INTERVENTIONS

The patient initially underwent conservative treatment for suspected hemangioma. Tumorrectomy was undergone after three weeks based on previously dissatisfied therapeutic effects.

OUTCOMES

The patient died of multiple distant metastases despite undergoing postoperative chemotherapy and metastasectomies.

LESSONS

Fetal or neonatal soft tissue ES may be clinically misdiagnosed as a hemangioma. It is important to suspect this through an imaging approach such as diffusion-weighted imaging.

Benefit of Sunitinib in the treatment of pulmonary primitive neuroectodermal tumors: a case report and literature review

Primitive neuroectodermal tumor (PNET) is a highly aggressive small round celltumor but is extremely rare in the lung. Next-generation sequencing (NGS) has led to breakthroughs for genetic analyses and personalizedmedicine approaches for cancer treatment.We report the case of a 30-year-old woman with an advanced pulmonary PNET treated with multiple chemotherapeutic regimens, and achieved a partial response (PR) as a best response. However, there was a disease progression after these treatment regimens.The NGS revealed the presence of a copy number loss (CNL) of Von Hippel-Lindau (VHL), CDKN2A/B and TP53 genes. The specific VHL CNL has not previously been associated with PNET, but has been reported in other tumors and has been associated with response to Sunitinib. Sunitinibwas then instituted for this patient and resulted in PR after the failure of multiple chemotherapeutic regimens. To our knowledge, this is the first report of pulmonary PNET with CNL of VHL gene that benefits from Sunitinib treatment. This case illustrates the potential of clinicalNGS to open unexpected avenues for treatment and thereby improve patient outcomes.

Recurrent BCOR Internal Tandem Duplication and YWHAE-NUTM2B Fusions in Soft Tissue Undifferentiated Round Cell Sarcoma of Infancy: Overlapping Genetic Features With Clear Cell Sarcoma of Kidney

Soft tissue undifferentiated round cell sarcoma (URCS) occurring in infants is a heterogenous group of tumors, often lacking known genetic abnormalities. On the basis of a t(10;17;14) karyotype in a pelvic URCS of a 4-month-old boy showing similar breakpoints with clear cell sarcoma of kidney (CCSK), we have investigated the possibility of shared genetic abnormalities in CCSK and soft tissue URCS. Most CCSKs are characterized by BCOR exon 16 internal tandem duplications (ITDs), whereas a smaller subset shows YWHAE-NUTM2B/E fusions. Because of overlapping clinicopathologic features, we have also investigated these genetic alterations in the so-called primitive myxoid mesenchymal tumor of infancy (PMMTI). Among the 22 infantile URCSs and 7 PMMTIs selected, RNA sequencing was performed in 5 and 2 cases, with frozen tissue, respectively. The remaining cases with archival material were tested for YWHAE-NUTM2B/E by fluorescence in situ hybridization (FISH) or reverse transcription-polymerase chain reaction (RT-PCR), and BCOR ITD by PCR. A control group of 4 CCSKs and 14 URCSs in older children or adults without known gene fusion and 20 other sarcomas with similar histomorphology or age at presentation were also tested. A YWHAE-NUTM2B fusion was confirmed in the index case by FISH and RT-PCR, whereas BCOR ITD was lacking. An identical YWHAE-NUTM2B fusion was found in another URCS case of a 5-month-old girl with a back lesion. The remaining cases and control group lacked YWHAE gene rearrangements; instead, consistent BCOR ITDs, similar to CCSK, were found in 15/29 (52%) infantile sarcoma cases (9/22 infantile URCS and 6/7 PMMTI). In the control cohort, BCOR ITD was found only in 3 CCSK cases but not in the other sarcomas. Histologically, URCS with both genotypes and PMMTI shared significant histologic overlap, with uniform small blue round cells with fine chromatin and indistinct nucleoli. A prominent capillary network similar to CCSK, rosette structures, and varying degree of myxoid change were occasionally seen. BCOR ITD-positive tumors occurred preferentially in the somatic soft tissue of the trunk, abdomen, and head and neck, sparing the extremities. RNAseq showed high BCOR mRNA levels in BCOR ITD-positive cases, compared with other URCSs. In summary, we report recurrent BCOR exon 16 ITD and YWHAE-NUTM2B fusions in half of infantile soft tissue URCS and most PMMTI cases, but not in other pediatric sarcomas. These findings suggest a significant overlap between infantile URCS and CCSK, such as age at presentation, histologic features, and genetic signature, thus raising the possibility of a soft tissue counterpart to CCSK.

Primitive neuroectodermal tumor of the kidney: case report and review of literature

BACKGROUND

Renal primitive neuroectodermal tumor (rPNET) as a member of Ewing's sarcoma family is extremely rare and usually occurs in children and young adults. Most literature about rPNET was isolated case reports.

CASE PRESENTATION

We reported a case of 45-year-old man with the complaint of right flank pain. Computerized tomography (CT) scan demonstrated a large substantive tumor involving the lower pole of the right kidney. Then the patient underwent radical nephrectomy. Pathologic characteristics and immunohistochemical analysis confirmed the diagnosis of rPNET. Additionally, the patient received three cycles of chemotherapy, and was still alive without metastasis at 15-months follow-up.

CONCLUSION

rPNET is rare and presents aggressive clinical behavior and worse prognosis. We expect that further awareness and study of this rare tumor can be had by presenting our case.

A case of malignant small round cell tumor of temporal bone with facial paralysis

Malignant small round cell tumor is very rare, especially in the head and neck area. It is also difficult to make a differential diagnosis due to their undifferentiated or primitive character. Immunohistochemical staining and chromosomal study is useful to categorize these tumors. Since these are rare tumors, treatment protocols are is not well established. While combined treatments (surgery, chemotherapy, radiotherapy) is currently being applied, the tumor still has a poor prognosis. We present a rare case of a rapidly growing temporal bone malignant small round cell tumor which initially showed facial paralysis.