Teratoma with a malignant somatic component in pediatric patients: the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) experience

Children's Oncology Group's 2023 blueprint for research: Germ cell tumors

Extracranial germ cell tumors (GCT) are a biologically diverse group of tumors occurring in children, adolescents, and young adults. The majority of patients have excellent outcomes, but treatment-related toxicities impact their quality of survivorship. A subset of patients succumbs to the disease. Current unmet needs include clarifying which patients can be safely observed after initial surgical resection, refinement of risk stratification to reduce chemotherapy burden in patients with standard-risk disease, and intensify therapy for patients with poor-risk disease. Furthermore, enhancing strategies for detection of minimal residual disease and early detection of relapse, particularly in serum tumor marker-negative histologies, is critical. Improving the understanding of the developmental and molecular origins of GCTs may facilitate discovery of novel targets. Future efforts should be directed toward assessing novel therapies in a biology-driven, biomarker-defined, histology-specific, risk-stratified patient population. Fragmentation of care between subspecialists restricts the unified study of these rare tumors. It is imperative that trials be conducted in collaboration with national and international cooperative groups, with harmonized data and biospecimen collection. Key priorities for the Children's Oncology Group (COG) GCT Committee include (a) better understanding the biology of GCTs, with a focus on molecular targets and mechanisms of treatment resistance; (b) strategic development of pediatric and young adult clinical trials; (c) understanding late effects of therapy and identifying individuals most at risk; and (d) prioritizing diversity, equity, and inclusion to reduce cancer health disparities and studying the impacts of social determinants of health on outcomes.

Morphological spectrum and molecular features of somatic malignant transformation in germ cell tumours

AIMS

Somatic malignant transformation (SMT) arising in germ cell tumours (GCTs) is an infrequent, but clinically relevant event. There is only limited knowledge on the morphological spectrum of SMT, and therapeutic management of these patients is poorly defined. In this work we revisit two consecutive case series (n=756) of GCTs. Clinicopathological data of SMT arising in GCT were determined, with focus on the histopathological spectrum, and molecular aspects were obtained by Fluorescence in situ Hybridization (FISH) and Next Generation Sequencing (NGS).

METHODS AND RESULTS

30 male patients (28 primary testicular, 2 primary extragonadal) were included. These patients represent 4% of GCT patients diagnosed in two institutes (University Hospital Zurich and IPO Porto). The most common SMT were adenocarcinoma (n=8), embryonic-type neuroectodermal tumours (ENETs, n=8) and rhabdomyosarcoma (n=6), but a wide range of challenging morphologies were depicted, including low-grade neuroglial tumour, adenosquamous carcinoma, neuroblastoma and neuroendocrine carcinoma. SMT was found in 15 primary tumour samples and in 27 metastatic samples of these 30 patients, the latter showing poorer overall-survival. Adenocarcinoma occurred only in metastasis post-chemotherapy and in one primary retroperitoneal GCT with SMT, but not in GCT of the testis. 12p gains were identified by FISH in all cases. NGS results were available in 6 patients. Clinical trials and/or targeted treatments based on the molecular profile of SMT were recommended in 4 patients.

CONCLUSIONS

SMT arising in GCTs represents a diagnostic challenge and should be confirmed by a specialized uropathologist. NGS based treatment recommendations may improve outcome of these patients.

Therapeutic strategies for uncommon testis cancer histologies: teratoma with malignant transformation and malignant testicular sex cord stromal tumors

Testicular cancer is the most common solid malignancy in male adolescents and young adults, with germ cell derived seminomas and non-seminomas being by far the most common histologies. Teratoma with somatic-type malignancy is a rare chemo-resistant phenotype of testis cancer associated with poor prognosis in patients with advanced stage disease. Malignant gonadal-stromal tumors comprise 5% of testicular neoplasms and approximately 10% are malignant and considered chemo-radiation resistant. Prognostic factors and treatment strategies for these uncommon histologies are lacking.

Rhabdomyosarcoma arising from retroperitoneal teratoma in an infantile neurofibromatosis type 1 patient

We herein report the case of a 2-year-old girl with neurofibromatosis type 1 (NF1), who presented with a 12-cm mass in the right retroperitoneum and underwent tumor resection. Histologically, the tumor was composed of two distinct components: one was teratoma, showing mature morphology; and the other was embryonal rhabdomyosarcoma. An interphase fluorescence in situ hybridization (FISH) analysis of the rhabdomyosarcoma component revealed the absence of isochromosome 12p. Although it is well known that rhabdomyosarcoma occurs in infantile NF1, and that rhabdomyosarcoma can arise from teratoma as a somatic-type malignancy, to the best of our knowledge, this is the first case of an infantile NF1 patient, who developed rhabdomyosarcoma within a retroperitoneal teratoma. The absence of chromosome 12p alteration suggests a possibility that the rhabdomyosarcoma occurred due to the NF1 background, not as a somatic-type malignancy of germ cell tumor.

Serum α-fetoprotein in pediatric oncology: not a children’s tale

Background

Measurement of α-fetoprotein (AFP) concentrations in the serum of infants is useful for the management of testicular germ cell tumors, hepatoblastoma and hepatocellular carcinoma. Here, we provide a critical review of the available information about pediatric reference intervals (RI), focusing on their utility in interpreting AFP as an aid for cancer diagnosis.

Content

Evidence sources in the available literature were critically appraised. Out of 3873 retrieved papers, 24 were finally selected and carefully inspected, and six of them overcame exclusion criteria (i.e. methodological limitations in the study design, statistical gaps, drawbacks in traceability of the AFP assay to higher order materials and/or biased reporting of AFP results). Preterm and term infants up to the 3rd month of life exhibited the highest average AFP concentrations, but the attempt of defining RI by data pooling and partitioning for age intervals was impeded by the wide variability of data. The inability of defining robust RI in the first months of life made difficult, if not impossible, using upper reference limits for ruling out malignancies with a single AFP result. Evaluating the behavior of AFP concentrations 5 days from the baseline result, if this exceeds risk thresholds partitioned for age, according to the formula Xt=X0*2−t/HL (where: t=days elapsed for AFP retest; HL=AFP half-life according to age; X0=AFP baseline concentration, and Xt=predicted AFP concentration at day 5), could give a better information.

Summary

Novel studies defining AFP RI in infants based on robust methodology are warranted to improve the interpretation of AFP results in pediatric oncology. In the meantime, algorithms based on both serum AFP absolute concentrations and HL may aid in cancer diagnosis.

Gonadal dysgenesis is associated with worse outcomes in patients with ovarian nondysgerminomatous tumors: A report of the Children's Oncology Group AGCT 0132 study

PURPOSE

In this report, we characterize the timing and behavior of malignant ovarian germ cell tumors (GCTs) in pediatric patients with dysgenetic gonads compared to those with normal gonadal development.

PATIENTS AND METHODS

Patients from the Children's Oncology Group AGCT0132 with malignant ovarian GCTs were included. Within this population, we sought to identify patients with gonadoblastoma, streak ovaries, or other evidence of gonadal dysgenesis (GD). Patients with malignant GCTs containing one or more of the following histologies-yolk sac tumor, embryonal carcinoma, or choriocarcinoma-were included. Patients were compared with respect to event-free survival (EFS) and overall survival (OS).

RESULTS

Nine patients with GD, including seven with gonadoblastoma (mean age, 9.3 years), were compared to 100 non-GD patients (mean age, 12.1 years). The estimated 3-year EFS for patients with GD was 66.7% (95% CI 28.2-87.8%) and for non-GD patients was 88.8% (95% CI 80.2-93.8%). The estimated 3-year OS for patients with GD was 87.5% (95% CI 38.7-98.1%) and for non-GD patients was 97.6% (95% CI of 90.6-99.4%).

CONCLUSION

Patients presenting with nongerminomatous malignant ovarian GCTs in the context of GD have a higher rate of events and death than counterparts with normal gonads. These findings emphasize the importance of noting a contralateral streak ovary or gonadoblastoma at histology for any ovarian GCT and support the recommendation for early bilateral gonadectomy in patients known to have GD with Y chromosome material. In contrast to those with pure dysgerminoma, these patients may represent a high-risk group that requires a more aggressive chemotherapy regimen.

Primary malignant melanoma arising in an ovarian cystic teratoma

Primary malignant melanoma arising in an ovarian cystic teratoma is exceedingly rare event with an estimated incidence of 0.2-0.8%. So far, there have been approximately only 47 relevant reports. We report a case of primary malignant melanoma of the ovary arising in a cystic teratoma here. Moreover, we review systematically the disease from the following aspects, that origin, clinical characteristics, accessory examination, pathological features, diagnosis, differential diagnosis, treatment, prognosis.

Immature Ovarian Teratoma: When to Give Adjuvant Therapy?

The question of giving or not adjuvant chemotherapy in pure ovarian immature teratomas (ITs) remains unsolved to date and illustrates differences in management between pediatric and adults oncologists. Because of the rarity of these tumors, this question has never been addressed through randomized trials. Standard of care for adult women with ovarian ITs is postoperative platinum based chemotherapy for all patients except FIGO stage IA, grade 1 tumors, whereas pediatric series concluded that surgery alone is curative for completely resected ovarian ITs, regardless of grade. Moreover the role of chemotherapy in incompletely resected tumors and its impact on the rate of malignant relapses needs to be better assessed. This emphasizes the urgent need for cooperation between adult and pediatric teams.

Two Tumors in 1: What Should be the Therapeutic Target? Pediatric Germ Cell Tumor With Somatic Malignant Transformation

BACKGROUND

Germ cell tumors with somatic malignant transformation (GCT with SMT) are rare in children and poorly described. Data are missing to determine if therapies should target the GCT, the SMT compound, or both simultaneously.

PATIENTS AND METHODS

A retrospective national study was conducted in the Société Française des cancers de l'Enfant (SFCE) Centers. Medical records from patients aged 0 to 18 years diagnosed with GCT with SMT between 2000 and 2015 were analyzed. Any stages and primary sites were considered as well as synchronous and metachronous cases.

RESULTS

Fifteen patients were identified. Thirteen patients had synchronous GCT with SMT. In the latter cases, primaries were ovary (5), mediastinum (3), pineal gland (3), sacrococcyx (1), and parametrium (1). SMT histologies were central primitive neuroectodermal tumor (5), embryonal rhabdomyosarcomas (3) or thyroid papillary adenocarcinoma, leukemia, poorly differentiated carcinoma, mixed sarcomas, and miscellaneous histology (1 case each). Chemotherapy was targeted against the GCT (3), the SMT (6), or both components (3). The last patient received surgery exclusively. Partial or complete response to chemotherapy was observed in 5/10 assessable cases: 2/3 patients treated with GCT-dedicated chemotherapy, 3/6 patients treated with SMT-dedicated therapy, and 0/1 treated with combined therapy. In addition, 2 patients with mediastinal GCT primary had metachronous SMT, with acute myeloid leukemia and thyroid papillary adenocarcinoma, 8 months and 8 years, respectively, after the diagnoses of GCT. Two patients (1 synchronous and 1 metachronous) were cured with surgery exclusively. At the end of follow-up, 6 patients died of their disease including all 4 with postsurgical macroscopic residue.

CONCLUSIONS

GCT with SMT constitutes a very rare entity in children and adolescents. Surgical removal of the tumor is the cornerstone of the treatment and might be sufficient in selected cases. In the remaining cases, the best management is still unknown and should take into account both components and their respective chemosensitivity. Long-term surveillance is advised for patient with unresected teratoma as late transformation can occur.

Perspectives in Pediatric Pathology, Chapter 25. Testicular and Paratesticular Tumors in the Pediatric Age Group

Testicular tumors in the prepubertal age are relatively rare, representing only 9.4% of the total testicular and paratesticular specimens from a 20-year review performed at a large pediatric hospital [ 1 ]. They account for 1% to 2% of all solid tumors in the pediatric age group, with an annual incidence between 0.5/100 000 and 2/100 000 boys according to Coppes et al [ 2 ] and data from the Prepubertal Testicular Tumor Registry [ 3 ]. Similar to other neoplasms afflicting children, a bimodal age distribution is observed. The first peak is between birth and 3 years of age, and a second one occurs at the onset of puberty, extending to the fourth decade. Reports on their frequency vary because some investigators include the adolescent period, while others do not [ 4 ]. The vast majority of testicular tumors are germ cell neoplasms, accounting for 95% across all ages [ 5 ]. In children, germ cell tumors also predominate, representing 71% of all testicular neoplasms. These include yolk sac tumors (49%), teratomas (13%), seminomas and mixed germ cell tumors (9%), and sex-cord stromal tumors (29%). Malignant potential is significantly lower (less than 70%) in the pediatric age group compared to adults (90%) [ 6 ]. According to Pohl et al, 74% of prepubertal testicular tumors are benign [ 7 ].

Mature and immature teratoma: A report from the second Italian pediatric study

BACKGROUND

Teratomas demonstrate a benign clinical behavior, however they may recur with malignant components or as teratoma, and in a small group of patients prognosis could be fatal. After the first Italian study, we collected cases of teratoma, alongside the protocol for malignant germ cell tumors.

PROCEDURE

Patients with teratoma were collected from 2004 to 2014. Teratomas were classified according to the WHO classifications, as mature and immature. Patients with pathological aFP and/or bHCG, and those with a malignant germ cell component were not included.

RESULTS

The study enrolled 219 patients (150 mature, 69 immature teratomas) with a median age at diagnosis of 42 months. The primary sites involved were: 118 gonadal and 101 extragonadal teratomas. Two females with ovarian teratoma had a positive family history. Complete and incomplete surgeries were performed in 85% and 9% of cases. Seventeen events occurred: six females had a second metachronous tumor (5 contralateral ovarian teratoma, 1 adrenal neuroblastoma) and 11 teratomas relapsed/progressed (3 mature, 8 immature teratomas). Two patients died, one of progressive immature teratoma and one of surgical complications. At a median follow up of 68 months, the event-free, relapse-free, and overall survival rates were 90.6%, 94.3%, 98.6%, respectively.

CONCLUSIONS

Teratomas show a good prognosis, especially the mature ones: surgery and follow-up remain the standard approach. Incomplete surgery in immature teratoma is the group at greatest risk of relapse. Bilateral ovarian tumors are a possibility, and the rare family predisposition to ovarian mature teratoma warrants further analyses.

An infant with a diagnostically challenging hepatic teratoma, hypofibrinogenemia, and adrenal neuroblastoma: case report

Teratomas of the liver are exceedingly rare. Neuroblastoma is the most common, extracranial solid tumor of infancy. We describe the case of a 2-month-old, female infant who presented with an abdominal mass arising in the right lobe of the liver, and a severe coagulopathy, which necessitated cryoprecipitate infusion. Biopsy was interpreted as hepatoblastoma. Following resection, difficulty classifying the mass led to several consultations, and an eventual diagnosis of teratoma. During follow-up, the patient was diagnosed with right adrenal neuroblastoma, which, in retrospect, had been present before the hepatic resection. To our knowledge, these 2 tumors have never been reported together, or in combination with isolated hypofibrinogenemia.

Secondary malignant transformation of testicular teratomas: case series and literature review

BACKGROUND

Teratomas are a spectrum of neoplasms that can undergo malignant transformation. In the World Health Organization (WHO) classification of tumors, this entity was classified as «teratoma with somatic-type malignancy», was defined as a malignant neoplasm of non-germinal phenotype that originates in a teratoma.

MATERIALS AND METHODS

We present a serie of nine cases of testicular teratomas with secondary malignant transformation. From January 1995 to December 2011, we found a total of 306 cases of testicular tumors. Mixed germ cell tumors were the most frequently diagnosed malignancy with 45.7%.

RESULTS

Teratoma with secondary malignant transformation, represented 2.9% of all germinal tumors. Five cases originated within a mixed germ cell tumor, two cases from mature teratomas, and two from immature teratomas. The predominante malignant somatic component were sarcomas; two cases of chondrosarcoma, one rhabdomyosarcoma, and one case showing foci of chondrosarcoma and rhabdomyosarcoma. The case of osteosarcoma is notable for its rarity. Two cases showed epithelial malignancy in the form of an adenocarcinoma, and finally, two cases were primitive neuroectodermal tumors. At the time of diagnosis, five patients had metastases.

CONCLUSION

The transformation of germ cell tumors to somatic type malignancies is rare. The malignant component can originate from any of the three germ lines. These tumors are resistant to standard chemotherapy for a germ cell tumor and the clinical stage is the most important prognostic factor. At our institution, the malignant component that appeared most frequently was chondrosarcoma.

Primary ovarian malignant melanoma arising in teratomatous component of mixed- germ cell tumor in a child: case report

Primary ovarian malignant melanoma arising in teratomatous component of germ cell tumors is seen extremely rare with most reports being only of single cases and small series in reproductive aged woman and mostly from cystic teratoma, whereas information on pediatric presentation is sparse. This case is reported for being extremely rare tumor.

Teratoma with somatic-type malignant components of the testis. A review and an update

Malignant transformation of germ cell tumors into somatic malignancy is uncommon. Its presentation differs from series to series, with 43 % of adult cases identified within the primary tumors and the remainder at the time of relapse or in the metastasis. Patients with stage I disease enjoy an excellent prognosis; whereas in metastatic sites when not completely resectable, the somatic type malignancies suffer a dismal prognosis. Radical surgery is significant for the prospects of cure and is standard chemotherapy for germ cell tumors; a transformation-oriented treatment can be effective for these patients. A deeper understanding of the biology of this phenomenon is essential for clinicians involved in such malignancies in order to permit a better control of the disease.

Teratoma of the lumbosacral region: a case report

Introduction

Teratoma is a tumor that usually arises from one or more germ layers. They are most commonly found in the sacrococcygeal region and have a female preponderance. We present a very rare case of a boy with a benign cystic teratoma in the lumbosacral region.

Case presentation

A 16-year-old Indian boy presented to our hospital with a history of a lump in the lower back region since birth. Initially, it was small, but its size increased gradually over time to a size of 15 cm × 15 cm at presentation. There were no other associated abnormalities. Investigations revealed the lump to be a benign cystic teratoma. The patient underwent surgery, and the whole tumor, from its base to the vertebrae, was excised. Bisection of the tumor revealed that it contained hair and pultaceous material consistent with a teratoma, which was later confirmed by histopathologic examination.

Conclusion

Benign cystic teratomas should be diagnosed and managed aggressively because they generally have a greater tendency to progress toward malignancy. After extensively searching the case report database, we arrived at the conclusion that this was a rare case of a benign cystic teratoma in the lumbosacral region in a boy.

Malignant steroidogenic tumor arising from sacrococcygeal mature teratoma

We report a case of malignant steroidogenic tumor arising from a sacrococcygeal teratoma in a 5-year-old girl. A congenital gluteal mass and a 7-month history of precocious puberty had been noted, and a large estrogen-producing tumor in the sacrococcygeal area was found. After a biopsy, chemotherapy and tumor resection were performed, and no recurrence has been observed. The biopsy specimen showed small clusters of atypical round cells adjacent to a mature teratoma. They had large round nuclei with prominent nucleoli and abundant eosinophilic cytoplasms and were positive for vimentin, steroidogenic factor-1, inhibin α, and melan-A. Increased mitoses, vascular invasion, and necrosis were noted. The tumor was diagnosed as sacrococcygeal mature teratoma, with malignant steroidogenic tumor as somatic malignant transformation. Although several kinds of somatic malignant transformation of sacrococcygeal teratoma have been reported, to the best of our knowledge, this is the first case of malignant steroidogenic tumor arising from sacrococcygeal teratoma.