Neuroblastoma metastatic to the testis: ultrasonographic screening as an aid to clinical staging

Testis Involvement in Neuroblastoma: Report of 3 Cases in the Turkish Pediatric Oncology Group-Neuroblastoma Study and Review of the Literature

BACKGROUND

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. Primary and secondary testicular involvement is extremely uncommon in neuroblastoma.

PROCEDURE

All children with neuroblastoma treated with the Turkish Pediatric Oncology Group (TPOG)-Neuroblastoma (NB) Study and who had testis involvement either at diagnosis or at relapse were retrospectively evaluated. A review of all cases with neuroblastoma and testis involvement in the literature was done.

RESULTS

There were 3 children with NB documented to have involvement of the testis, 2 at diagnosis, 1 at recurrence, within the 559 cases (0.5%) treated with the Turkish Pediatric Oncology Group (TPOG)-Neuroblastoma Protocol. All had advanced stage. Two were infants. A total of 57 cases of testicular or paratesticular neuroblastoma have been reported in children, and most cases represent metastases as in the 3 cases in our series.

CONCLUSIONS

Neuroblastoma should be considered in the differential diagnosis of testicular mass and work-up for neuroblastoma should be done before orchiectomy. Scrotal ultrasonography should be used as the first diagnostic tool and abdominal ultrasonography shall be done additionally. Testis examination should be performed at diagnosis and regularly during follow-up for boys diagnosed with neuroblastoma. Testes may be sanctuary sites when neuroblastoma is metastatic, as is the case in leukemia.

RT-qPCR for PHOX2B mRNA is a highly specific and sensitive method to assess neuroblastoma minimal residual disease in testicular tissue

Neuroblastoma (NB) is the most common type of extracranial solid tumor in children with a high prevalence in toddlers. For childhood cancer survivors, preservation of reproductive potential is an important factor for quality of life. The optimization of NB minimal residual disease (MRD) detection in testicular tissue is crucial to evaluate the risk of malignant cell reintroduction. The first step in the present study was to assess the accuracy of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to detect tyrosine hydroxylase (TH), paired-like homeobox 2b (PHOX2B) and doublecortin (DCX) mRNA expression in frozen/thawed testicular tissues of patients with non-obstructive azoospermia (NOA) contaminated (in vitro model) with an increasing number of IMR-32 and SK-N-SH NB cells. Testicular tissues were frozen by slow or snap freezing. The second step was to determine the expression levels of these markers in testicular samples from 4 pre-pubertal males (2 with stage IV NB and 2 with non-NB malignancy). The yield of extracted RNA was similar in testicular samples frozen by slow or snap freezing. In the in vitro model, TH and DCX transcripts were detected in uncontaminated testicular tissues, whereas PHOX2B mRNA was not detected. There was a strong positive association between the number of NB cells used for contamination and PHOX2B transcript levels. For IMR-32 and SK-N-SH NB cell lines, specificity and sensitivity rates of detection were 100% for PHOX2B following in vitro contamination with 10 tumor cells. In testicular samples from pre-pubertal males with and without NB, PHOX2B mRNA expression was not observed, but high expression levels of TH and DCX mRNA were detected, which were similar to expression detected in the in vitro model. Among the markers used in blood and bone marrow for NB MRD studies, the detection of PHOX2B transcripts by RT-qPCR may provide an accurate assessment of NB cells in testicular tissues from males who require fertility preservation.

Outcome of paratesticular involvement in infants with neuroblastoma

The authors report on 3 infants suffering from disseminated neuroblastoma (NB) involving the testes or paratesticular structures. INSS stage 4 in 2 cases, and "biological" INSS stage 4S were considered, respectively. One patient with a stage 4 NB died of tumor progression; one patient is under therapy. The patient with NB 4S was cured with preservation of both testes after antineoplastic chemotherapy and reduction of the retroperitoneal primary. J Pediatr Surg 36:E23.

Testicular and paratesticular involvement by metastatic neuroblastoma

BACKGROUND

Testicular and paratesticular involvement is a less familiar feature in neuroblastoma and its prognostic impact is unclear.

METHODS

The records of 1076 male patients in the German cooperative neuroblastoma treatment trials were searched for patients with testicular or paratesticular involvement.

RESULTS

The authors found 11 children with paratesticular or testicular involvement at the time of manifestation of the disease, 3 children with testicular involvement at the time of relapse, and 1 infant with testicular involvement at the time of progression of neuroblastoma from International Neuroblastoma Staging System (INSS) Stage 4S to Stage 4. In de novo disease, the age of manifestation did not exceed 12 months. Two children had paratesticular involvement per continuitatem by growth of a primary tumor through the inguinal channel. All others had distant primary tumor. Prognosis appeared more favorable for infants (3 of 9 died) than for older children (5 of 6 died), for children with involvement of testes and < 10% involvement of bone marrow (2 of 8 died) than for children with other distant metastasis (6 of 7 died), and for children with intrascrotal involvement at first diagnosis (4 of 11 died) than for children with intrascrotal involvement during relapse of the disease (all 4 children died).

CONCLUSIONS

Paratesticular or testicular metastasis does not per se indicate unfavorable outcome and is compatible with INSS Stage 4S in infants. The age at diagnosis and the time of manifestation during disease contributed to the prognosis in those patients.

Neuroblastoma with spermatic cord metastasis in a child: sonographic findings

We report a case of neuroblastoma in a patient who had no involvement of the spermatic cord at diagnosis but who developed spermatic cord metastasis 2 months later. The metastasis appeared on sonography as a hypoechoic, highly vascular, fusiform, hard, 14x10x7 mm mass located in the right inguinal canal and extending into the scrotum. The diagnosis of spermatic cord metastasis was confirmed by resection and histopathologic examination. We recommend that the scrotum and spermatic cord be evaluated by high-resolution sonography in children with neuroblastoma, both at the time of diagnosis and during follow-up.

Primary neuroblastoma presenting as a paratesticular tumor

A 3-month-old boy was operated on for an inguinal tumor. Histological diagnosis was neuroblastoma. This is the second known case of primary paratesticular neuroblastoma reported in the literature. The treatment of choice for Evan's stage I is surgery.

Sonographic findings of testicular teratoma with pathologic correlation

Testicular teratoma is a rare tumor in children. We recently encountered two boys, aged 18 months and 2 years respectively, with this tumor. Sonography revealed an intratesticular mass in both. The first revealed a predominantly cystic lesion with echogenic components along its wall. The second showed a complex mass occupying most of the right testicle, and containing several areas of calcifications and cysts. Excellent pathologic correlation was obtained in both. Preoperative diagnosis of testicular teratoma is possible if the characteristic features are recognized. The prognosis is good following orchiectomy in the pediatric patients.

Testicular metastasis from malignant schwannoma of chest wall

Metastatic malignancy to the testes is unusual. Reports of testicular metastasis of neurogenic tumor are extremely rare. Only 28 cases with testicular metastasis of neurogenic tumor have been reported in the world literature. Cases of primary malignant schwannoma with testicular metastasis have not been reported previously. We present an unusual case of a thirty-seven-year-old man who had a malignant schwannoma of the chest wall with testicular metastasis.

Prospective study of routine scrotal ultrasonography in urological practice

The value of routine scrotal ultrasonography has been evaluated in a prospective study of 109 men with scrotal symptoms or signs. Ultrasonography had a sensitivity of 100% and specificity of 99% for testicular tumour. Clinically useful information was provided in 53% of patients and 8% might have avoided surgery if the ultrasound report had been heeded. Ultrasonography did not provide any additional information in patients with scrotal pain and an entirely normal scrotum clinically, and in those with epididymal cysts in whom the testis was palpably normal. If these 2 groups had been excluded from routine scrotal ultrasonography there would have been a 25% reduction in the number of examinations without any reduction in diagnostic yield.

Testicular metastasis as the first manifestation of colon carcinoma

Metastatic carcinoma to the testes is uncommon, and it is most often found incidentally at autopsy or after orchiectomy for prostatic carcinoma. One of the rarest causes of testicular tumor is metastasis from another primary site. It is even more unusual when the metastasis to the testicle is the first manifestation of the tumor. We report a case of asymptomatic colon carcinoma presenting as metastases to the testis and epididymis, which was diagnosed after biopsy of testicular nodules. Although nonlymphomatous cancer presenting as an intrascrotal mass is extremely rare, seldom detected clinically and almost never the first sign of disease, it should be considered a possibility, even in the young adult who presents with a mass involving the testicle or epididymis.

Renal metastases from neuroblastoma. Report of two cases

Neuroblastoma is one of the pediatric cancers that has the most unpredictable evolution. It can metastasize to almost any organ, but intrarenal metastases have never been reported. We report 2 such cases: the first patient had a left adrenal neuroblastoma completely resected 10 months before routine follow up ultrasound and CT scan demonstrated 3 right intrarenal metastases. The second patient was being investigated for a left abdominal mass when one left intrarenal metastasis was found during the same CT scan. An intrarenal mass found during investigation for staging or follow up of neuroblastoma should then be considered as a metastase until proven otherwise.

Imaging of neuroblastoma: an overview

This review article briefly describes the pathology, clinical features, prognosis, and treatment of neuroblastoma. The emphasis is on applications of newer diagnostic modalities (sonography, nuclear scintigraphy, computed tomography) for imaging and staging. The potential role of magnetic resonance imaging and spectroscopy is discussed.

Metastatic neuroblastoma and testicular involvement

Neuroblastoma metastatic to the testes is thought to be an extremely rare event and is therefore not routinely considered in the evaluation of neuroblastoma patients. A review of metastatic sites in a series of neuroblastoma patients, however, revealed 11 cases with testicular involvement. Analysis of these cases suggests that the phenomenon may not be uncommon in a subset of neuroblastoma patients, namely, male patients with infra-diaphragmatic primaries and advanced-stage disease. Because the testes constitute a sanctuary site for tumor cells, occult testicular involvement may play a role in the relapse of patients judged to be in complete remission. Accordingly, it is proposed that in the above group of patients special diagnostic attention should be directed at the scrotal contents and, if testicular involvement is detected, orchiectomy or local irradiation should be considered.