Cytogenetic study of malignant triton tumor: a case report

Malignant triton tumor of the rectum - A case report and review of the literature

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Malignant triton tumor are rare tumors causing ileus.

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Multimodal treatment with repetitive surgical resection can improve outcome in MTT.

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MTT shows a high rate of local recurrence.

Introduction

Malignant triton tumors (MTT) are rare but highly aggressive tumors that originate from the Schwann cells. These tumors can occur in any part of the body, mostly present late and carry poor prognosis.

Presentation of case

We present a 24-year-old man with a rectal MTT causing non-specific abdominal pain and recurring ileus. The MRI showed a rectal mass near the urinary bladder with compression on the seminal vesical. A complete surgical resection of the tumor was performed. The immunohistological report confirmed a rectal MTT. Because of persistent ileus during the post-operative palliative chemotherapy, another tumor debulking was performed. The patient died 9 months after the diagnosis of MTT due to local recurrence under chemotherapy.

Discussion and conclusion

MTTs are uncommon tumors in young age with high morbidity and mortality because of local recurrence also after complete resection.

Retroperitoneal malignant triton tumor in an infant: a case report and literature review

Malignant triton tumor (MTT) is a rare subtype of malignant peripheral nerve sheath tumor (MPNST) with rhabdomyoblastic differentiation. MTTs are solid tumors commonly located in the head, neck, extremities, and trunk. The presence of this tumor in an infant's retroperitoneum is extremely rare, and prompted the authors to report this case with reference to existing literature.

Elbow flexion reconstruction after arm-sparing excision for high-grade triton sarcoma: a case report

Background

Soft tissue sarcomas affecting the root of an upper extremity raise the question of limb amputation depending on their location, size, and malignancy. Malignant triton tumors are a rare subtype of neurofibrosarcomas that have been poorly reported in the literature. We report the case of a challenging reconstruction of the upper extremity using a pedicled latissimus dorsal flap.

Case presentation

A 25-year-old Occidental man was referred to our sarcoma unit for the management of a large, high-grade malignant peripheral nerve sheath tumor with no regional or distant extension and very fast progression. He was treated first by concomitant neoadjuvant radiotherapy and chemotherapy. Carcinologic excision was performed “en bloc” including the skin, the tumor, and the flexor muscles of our patient’s elbow. Coverage of the skin defect and elbow flexion restoration were achieved by using a homolateral pedicled musculocutaneous latissimus dorsi flap. Histological analysis showed an R0 resection. The reconstruction process recovered a complete bending of his elbow. He is still in remission at 26 months follow-up.

Conclusions

A malignant triton tumor is a rare, aggressive, and high-grade sarcoma. It was successfully treated and this case report describes an effective treatment modality. Reconstructive surgery, allowing large, complete tumor removal, is indispensable after neoadjuvant chemotherapy and radiotherapy.

Malignant triton tumor of the gluteal region in a patient unaffected by neurofibromatosis: A case report

Malignant triton tumor (MTT) is a rare variant of malignant peripheral nerve sheath tumor (MPNST) made up of both malignant schwannoma cells and malignant rhabdomyoblasts.

A 26-years-old male patient was admitted with an asymptomatic gluteal mass. Magnetic resonance imaging showed heterogeneous soft tissue mass and he underwent open biopsy. Malignant peripheral nerve sheath tumor was diagnosed. He was given adjuvant chemotherapy following the removal of the tumor with hip disarticulation. The tumor was diagnosed as “malignant triton tumor” based on pathological examination including immunohistochemical studies. There were no signs of metastasis but recurrence was observed at 9 months follow up.

MTT is usually associated with Neurofibromatosis 1 and located in head, neck region. In this case sporadic involvement of gluteal region and aggressive behavior of the lesion despite radical surgery was demonstrated.

Analysis of clinical features and prognosis of malignant triton tumor: A report of two cases and literature review

Malignant triton tumor (MTT) is a malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. The prognosis of patients is poor, and due to its rarity, large case studies are lacking. The aim of this study is to describe the clinical features and identify potential prognostic factors. Two patients with MTT in the head and neck treated at our department are reported. A literature search revealed another 198 published cases. All of these cases then went through a retrospective analysis. The ratio of male-to-female incidence was 1.5:1, and the median age at diagnosis was 29 years. In 41.7% of cases it occurred in patients with neurofibromatosis type 1. The five-year survival of MTT was found to be just 35%. Cox proportional hazards analysis revealed that complete resection (hazard ratio, 0.396; P=0.032) and metastases (hazard ratio, 3.188; P=0.004) were associated with mortality, indicating that complete resection may lead to a longer life span, and that the existence of metastasis suggested a worse prognosis for patients with MTT.

Low-grade malignant triton tumor of the neck: a case report and review of the literature

Rhabdomyoblastic differentiation in a malignant peripheral nerve sheath tumor (MPNST) is termed malignant triton tumor (MTT), a rare neoplasm that poses a diagnostic dilemma in the differential diagnosis of neck masses and portends poor prognosis. We report a sporadic case of MTT of the neck in a 23-year-old female. We present the pathological findings. Immunohistochemistry confirmed the neurogenic origin with S-100 expression and the rhabdomyoblastic differentiation with desmin and vimentin positivity. Radical surgical excision was done. After 4 years there were no signs of recurrence or distant metastasis. The clinical, microscopic, and long-term follow-up of this case are consistent with those of a low-grade malignancy.

Malignant Triton Tumor of the Sciatic Nerve as a Secondary Malignancy after Extended Field Radiotherapy and Chemotherapy of Hodgkin's Disease

Late effects of therapy for Hodgkin's disease include secondary malignancies like leukemia, lymphoma or solid tumors developing after long periods of latency. Ionizing radiation often causes the last group. The highest risks have been described for induced breast and lung cancers. We are the first to report a malignant triton tumor (MTT) as a secondary malignancy after radiotherapy and chemotherapy for Hodgkin's lymphoma. MTT is a very rare subtype of malignant peripheral nerve sheath tumors with rhabdomyoblastic differentiation and an aggressive course of disease.

Malignant triton tumor of the anterior mediastinum: A case report

Malignant triton tumors (MTTs) are a rare subtype of malignant peripheral nerve sheath tumor (MPNST) showing rhabdomyoblastic differentiation, which have no treatment consensus and a poor prognosis. This case report presented the case of a 42-year-old male patient with a large MTT located in the anterior mediastinum. The patient underwent palliative chemoradiotherapy and interstitial chemotherapy and received traditional Chinese medicine. Localization of an MTT in the anterior mediastinum is extremely rare. To the best of our knowledge, this is only the fourth study of an MTT localized in the anterior mediastinum that has been documented in the English literature.

Malignant triton tumor: a rare case

Malignant triton tumor (MTT) is a malignant peripheral nerve sheath tumor (MPNST) with rhabdomyoblastic differentiation. This rare tumor, with fewer than 100 cases reported in the literature, generally affects adult patients with neurofibromatosis 1 (NF-1). We report such a case in a 34-year-old man with NF-1 who presented with a mass over the medial side of the arm. Histopathologically finding of rhabdomyoblasts among malignant Schwann cells in a tumor arising from a peripheral nerve supported by immunostaining with S-100 protein and myogenin confirmed the diagnosis. MTT has a poor prognosis owing to its aggressive biological behavior. The fact that this tumor is extremely rare has prompted us to report this case.

Establishment and characterization of therapy-resistant mantle cell lymphoma cell lines derived from different tissue sites

Mantle cell lymphoma (MCL) is a rare but aggressive form of B cell non-Hodgkin lymphoma in which therapy resistance is common. New therapeutic options have extended survival in refractory MCL but have not provided durable remission. Tools are needed to assess the molecular and genetic changes associated with therapy resistance. Therefore, therapy-resistant MCL cell lines were established from the liver, kidney and lungs of human Granta 519-bearing NOD-SCID (non-obese diabetic-severe combined immunodeficiency) mice following treatment with CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy in combination with bortezomib. The cytomorphologies, immunophenotypes, growth patterns in semi-solid agar, cytogenetic profiles and gene expression differences between these cell lines were characterized to identify major changes associated with therapy resistance. Therapy-resistant cell lines exhibit more aggressive growth patterns and markedly different gene expression profiles compared to parental Granta 519 cells. Thus, these stable therapy-resistant cell lines are useful models to further study the molecular basis of drug resistance and to identify clinically relevant molecular targets in MCL.

Malignant triton tumor of the retroperitoneum: a case report and review of the literature

Background

Malignant triton tumors are relatively rare and highly aggressive tumors in which malignant schwannoma cells coexist with rhabdomyoblasts. Their occurrence in the retroperitoneum is uncommon and has been rarely reported.

Case presentation

We present the case of a patient with a retroperitoneal malignant triton tumor. A 32-year-old male was referred with epigastric pain and an abdominal mass. Computed tomography revealed a huge soft tissue retroperitoneal mass that involved adjacent organs and vessels. Complete resection was undertaken. Pathological examination confirmed the presence of a malignant triton tumor. The patient died two and a half months after surgery, as a result of local recurrence.

Conclusion

Malignant triton tumors are uncommon sarcomas that are associated with a high incidence of developing local recurrence and distant metastases. Immunohistochemical staining showing nerve sheath differentiation with rhabdomyoblastic cells confirms the diagnosis. Complete excision of the tumor is the most effective treatment strategy for these retroperitoneal tumors.

A rare case of malignant triton tumor in the cerebellopontine angle

Malignant triton tumor (MTT) is defined as malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. Intracranial MTT is extremely rare, and only four cases have been reported in the literature. Here, we report a case of MTT occurring in the cerebellopontine angle, and describe its histopathological characteristics, immunohistochemical features, and prognosis.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1336227313684480.

A Triton tumor mimicking sacrococcygeal teratoma

A newborn female infant delivered after a normal pregnancy was found to have a large sacrococcygeal mass. Imaging and laboratory studies suggested this was a sacrococcygeal teratoma. On the 16th day of age, the tumor was completely removed. Histopathologic examination of the tumor showed malignant Triton tumor (MTT). Thus, we describe a female newborn without a family history of neurofibromatosis with an MTT that mimics a sacrococcygeal teratoma. To our knowledge, this is the first report of a sacrococcygeal MTT detected in a neonate.

Malignant triton tumor in a patient with Li-Fraumeni syndrome and a novel TP53 mutation

We report a 3-year-old boy with a malignant triton tumor (MTT) involving the left masticator space with local invasion and regional lymph node metastasis. Family history and detection of a novel germline TP53 mutation confirmed his diagnosis of Li Fraumeni syndrome (LFS). MTT has not been previously described in association with LFS. This case along with a comprehensive review of the literature, illustrate the importance of both somatic and germline TP53 mutations in the pathogenesis MTT. The tumor could not be resected and he was successfully treated with intensive induction chemotherapy, irradiation, and high-dose chemotherapy with autologous stem cell transplantation.

Malignant triton tumor in a patient with neurofibromatosis type 1

We report a case of neurofibromatosis type 1 (NF1) complicated by a malignant triton tumor (MTT), with an emphasis on B-mode sonographic (US) and contrast-enhanced US (CEUS) findings. To the best of our knowledge, this is the first report describing CEUS findings of MTT. The mass was poorly demarcated and composed of an internal echogenic area and an outer hypoechoic zone. CEUS findings showed the outer zone to be strongly enhanced, and the internal area was very poor in blood flow because of necrotic tissues.

Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation (malignant triton tumor)

Malignant peripheral nerve sheath tumors arise from Schwann cells or within existing neurofibromas and have a strong association with type 1 neurofibromatosis. These tumors are histologically diverse and may contain malignant areas of divergent mesenchymal differentiation, the most common of which is skeletal muscle (rhabdomyosarcoma). Malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation is also known as malignant triton tumor. Malignant triton tumor has a worse prognosis than classic malignant peripheral nerve sheath tumor does, and the correct diagnosis requires attention to the clinical history and knowledge of the complexities regarding its differential diagnosis. In this review we discuss the clinical, histopathological, immunohistochemical, and prognostic features of this rare neoplasm.

Molecular cytogenetic analysis in the study of brain tumors: findings and applications

Classic cytogenetics has evolved from black and white to technicolor images of chromosomes as a result of advances in fluorescence in situ hybridization (FISH) techniques, and is now called molecular cytogenetics. Improvements in the quality and diversity of probes suitable for FISH, coupled with advances in computerized image analysis, now permit the genome or tissue of interest to be analyzed in detail on a glass slide. It is evident that the growing list of options for cytogenetic analysis has improved the understanding of chromosomal changes in disease initiation, progression, and response to treatment. The contributions of classic and molecular cytogenetics to the study of brain tumors have provided scientists and clinicians alike with new avenues for investigation. In this review the authors summarize the contributions of molecular cytogenetics to the study of brain tumors, encompassing the findings of classic cytogenetics, interphase- and metaphase-based FISH studies, spectral karyotyping, and metaphase- and array-based comparative genomic hybridization. In addition, this review also details the role of molecular cytogenetic techniques in other aspects of understanding the pathogenesis of brain tumors, including xenograft, cancer stem cell, and telomere length studies.

G-banding and molecular cytogenetic analyses of marginal zone lymphoma

We analysed the acquired chromosomal aberrations of 22 marginal zone lymphoma (MZL) patients by various genome-wide cytogenetic techniques, such as G-banding, multicolour fluorescence in situ hybridisation (M-FISH), cross-species colour banding (RxFISH), and comparative genomic hybridisation (CGH), as well as FISH with locus-specific probes. Patients with an abnormal chromosome 3 (n = 11), the most frequently rearranged chromosome, showed a shorter median survival than patients with a normal chromosome 3 (n = 11, 74 months vs. 219 months, P < 0.03). Four of five patients with nodal MZL had chromosome 3 abnormalities and patients with nodal MZL had a shorter median survival than patients in the other morphological subgroups of MZL (P < 0.003). CGH analysis showed only gains of chromosome material, namely of chromosome regions 3p12-25, 3q12-21, 3q23-28, 12q13-15, 12q22-24, 19p13 and 19q13 in two to four cases each (20-40%). In two MZL, the novel unbalanced translocation der(13)t(3;13)(q24;p11) was detected as the sole karyotypic rearrangement, indicating that gain of 3q24-qter could be an important event in the pathogenesis of these lymphomas. Another two cases showed, in addition to other abnormalities, a t(4;14)(p13;q32). Both these lymphomas had involvement of the IGH gene at 14q32, and one of them also of the RHOH/TTF gene at 4p13, which encodes a new member of the RHO protein subfamily.

Acquisition of i(8q) as an early event in malignant triton tumors

Malignant triton tumors (MTT) are rare soft-tissue tumors characterized by a mixture of cells with nerve sheath and skeletal muscle differentiation. MTT is a histological variant of malignant peripheral nerve sheath tumors (MPNST). No characteristic cytogenetic anomaly has been detected in MPNST or MTT. In this paper, we report on the cytogenetic findings of an MTT from a 20-year old male with neurofibromatosis (NF1). The tumoral karyotype showed the modal number to be near-diploid and an abnormal karyotype with a Robertsonian translocation and 4 markers: 49,XY,der(14;15)(q10;q10),+4mar. Spectral karyotyping revealed the karyotype: 49,XY, der(14;15)(q10;q10),+i(8)(q10)x4. Fluorescence in situ hybridization analysis of the tissue confirmed the presence of the additional i(8)(q10) in all tumoral cells. The sequence analysis of p53 revealed a polymorphism in exon 9, codon 329. The two alleles, TTC and TCC, codify for phenylalanine and serine, respectively. Our results indicate that all neoplastic cells have the same cytogenetic pattern, suggesting that both cell lines, which show nerve sheath and skeletal muscle differentiation, are derived from a unique stem cell. The acquired Robertsonian chromosomal recombinants might represent an event in the tumorigenesis of MTT, and the present data suggest that genes located on 8q can be involved in the development of MTT.

Recurrent chromosomal imbalances and structurally abnormal breakpoints within complex karyotypes of malignant peripheral nerve sheath tumour and malignant triton tumour: a cytogenetic and molecular cytogenetic study

BACKGROUND

Cytogenetic studies of malignant peripheral nerve sheath tumours (MPNSTs) and malignant triton tumours (MTTs) are rare.

AIMS

To undertake cytogenetic analysis of these tumours.

METHODS

Conventional cytogenetic analysis of 21 MPNSTs and MTTs from 17 patients (nine with peripheral neurofibromatosis (NF1)) was carried out using standard culture and harvesting procedures. For a more precise identification of composite structural rearrangements and marker chromosomes, spectral karyotypic analysis (SKY) was applied to a subset of cases. In addition, EGFR gene copy number was assessed by fluorescence in situ hybridisation (FISH) analysis in a subset of cases.

RESULTS

Cytogenetic analysis revealed predominantly complex karyotypes. SKY analysis was useful in further defining many structural anomalies. Structural aberrations most frequently involved chromosomal bands or regions 1p31-36, 4q28-35, 7p22, 11q22-23, 19q13, 20q13, and 22q11-13. Overall, loss of chromosomal material was much more common than gain. Loss of chromosomes or chromosomal regions 1p36 (48%), 3p21-pter (52%), 9p23-pter (57%), 10 (48%), 11q23-qter (48%), 16/16q24 (62%), 17(43%), and 22/22q (48%), and gains of 7/7q (29%) and 8/8q (29%) were most prominent. These gains and losses were distributed equally between MPNST and MTT, demonstrating that these entities are similar with respect to recurrent genomic imbalances. Similarly, none of the recurrent chromosomal breakpoints or imbalances was restricted to either NF1 associated or sporadic MPNSTs. FISH analysis was negative for amplification.

CONCLUSIONS

These cytogenetic and molecular cytogenetic findings expand the knowledge of chromosomal alterations in MPNST and MTT, and point to possible recurring regions of interest.

Malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation (malignant triton tumor) with balanced t(7;9)(q11.2;p24) and unbalanced translocation der(16)t(1;16)(q23;q13)

Malignant peripheral nerve sheath tumors (MPNST) with skeletal muscle differentiation are termed malignant triton tumors. A case of malignant triton tumor arising in a patient without signs of neurofibromatosis with two consistent chromosomal abnormalities is described. The first was of a balanced translocation between the long arm of chromosome 7 and the short arm of chromosome 9. The second was an unbalanced rearrangement between chromosomes 1 and 16, leading to partial trisomy for the long arm of chromosome 1 and partial monosomy for the long arm of chromosome 16. Review of previous reports on chromosomal abnormalities in malignant triton tumors revealed consistent abnormalities involving chromosome 1, regardless of the presence or absence of neurofibromatosis. This finding may relate to the observed poor prognostic outcome in this type of sarcoma. Also unique to our case is the translocation involving 7q and 9p, both regions may play a role in MPNST.