Teratocarcinosarcoma of the head and neck: Clinicopathologic review of a rare entity

Teratocarcinosarcoma is a rare, highly aggressive malignancy of the head and neck, characterized by multiphenotypic and triphasic growth of epithelial, mesenchymal, and primitive neuroepithelial elements. Owing to its rarity and morphological heterogeneity, as well as the lack of experience with this neoplasm, teratocarcinosarcoma is often misdiagnosed, particularly in small biopsy samples when only some of the elements are identified, thus leading to delayed management. Aggressive clinical behavior and poor survival outcomes, necessitate an accurate diagnosis and appropriate treatment. This review describes the main demographic and clinicopathological features of teratocarcinosarcoma, with an emphasis on the recent advances that have attempted to identify the molecular signature of this neoplasm.

Diagnostic algorithm for challenging blue cell sinonasal carcinoma

The newly emerging sinonasal carcinomas have demonstrated diverse morphologies and specific molecular rearrangements along with deviant clinical behavior from conventional counterparts. We aim to propose a diagnostic algorithm that is based on molecular findings of each sinonasal cancer and is considering the new entities has been called upon. Such a diagnostic algorithm should help diagnostic pathologists establish a diagnosis of a challenging sinonasal blue cell carcinomas and researchers performing retrospective analysis of archival cases. Along with consulting our archival cases, literature mining was conducted to retrieve the immunohistochemical and molecular findings regarding the newly emerging entities. Our proposed algorithm distinguishes poorly differentiated (non) keratinizing SNSCC, from anaplastic myoepithelial carcinoma, NUT midline carcinoma, SMARCB1/SMARCA4-deficient teratocarcinosarcoma, SMARCB1/SMARCA4-deficient carcinosarcoma, olfactory neuroblastoma, sinonasal undifferentiated carcinoma, HPV-related multiphenotypic sinonasal carcinoma and other adenocarcinomas. By incorporating morphologic features, immunohistochemical markers, and molecular investigations, the algorithm enhances the accuracy of diagnosis, particularly in cases where comprehensive molecular testing is not readily available. This algorithm serves as a valuable resource for pathologists, facilitating the proper diagnosis of sinonasal malignancies and guiding appropriate patient management.

Teratocarcinosarcoma-Like and Adamantinoma-Like Head and Neck Neoplasms Harboring NAB2::STAT6: Unusual Variants of Solitary Fibrous Tumor or Novel Tumor Entities?

The archetypal solitary fibrous tumor (SFT) features fibroblastic cells with varying cellularity without any particular architectural arrangement in a collagenous matrix, with staghorn vessels, CD34 and STAT6 expression, and NAB2::STAT6. To date, this fusion is thought to be specific for SFT. With more routine use of fusion gene panels, the histologic diversity of NAB2::STAT6-positive tumors is increasingly appreciated. Here we present four head and neck tumors harboring NAB2::STAT6 but exhibiting remarkably unusual morphologic features for SFT. All cases were pulled from the authors' consultation files. Immunohistochemistry was performed, along with targeted RNA sequencing in all cases, plus DNA next-generation sequencing on two. The cases arose in the nasal cavity (n = 2), retromolar trigone (n = 1) and parapharynx (n = 1), in patients ranging from 39 to 54 (mean, 44). Both nasal cases were biphasic, with a variably cellular collagenized stroma that resembled SFT but also interspersed malignant epithelial and neuroepithelial nests. One of the nasal cases also exhibited overt rhabdomyoblastic differentiation within both components. The two non-nasal cases were comprised of plump, epithelioid cells that were diffusely positive for pan-cytokeratin. One of these cases had prominent cystic change lined by overtly squamous epithelium. STAT6 immunostaining was positive in all cases, although the epithelial/neuroepithelial nests in the sinonasal cases were negative. All cases were confirmed to harbor NAB2::STAT6 by RNA sequencing. The two sinonasal cases were also found to harbor oncogenic mutations. The presented cases highlight a much broader histologic diversity than previously known for neoplasms with NAB2::STAT6. The biphasic nasal cases closely resemble teratocarcinosarcoma, while the epithelioid, cytokeratin-positive cases could be conceptualized as "adamantinoma-like," to borrow terminology already in use for Ewing sarcomas with complex epithelial differentiation. To identify similar cases, pathologists should have a low threshold for using STAT6 immunohistochemistry on any difficult-to-characterize head and neck tumor.

Proceedings of the North American Society of Head and Neck Pathology, Los Angeles, CA, March 20, 2022: SWI/SNF-deficient Sinonasal Neoplasms: An Overview

The pathology of poorly differentiated sinonasal malignancies has been the subject of extensive studies during the last decade, which resulted into significant developments in the definitions and histo-/pathogenetic classification of several entities included in the historical spectrum of "sinonasal undifferentiated carcinomas (SNUC)" and poorly differentiated unclassified carcinomas. In particular, genetic defects leading to inactivation of different protein subunits in the SWI/SNF chromatin remodeling complex have continuously emerged as the major (frequently the only) genetic player driving different types of sinonasal carcinomas. The latter display distinctive demographic, phenotypic and genotypic characteristics. To date, four different SWI/SNF-driven sinonasal tumor types have been recognized: SMARCB1(INI1)-deficient carcinoma (showing frequently non-descript basaloid, and less frequently eosinophilic, oncocytoid or rhabdoid undifferentiated morphology), SMARCB1-deficient adenocarcinomas (showing variable gland formation or yolk sac-like morphology), SMARCA4-deficient carcinoma (lacking any differentiation markers and variably overlapping with large cell neuroendocrine carcinoma and SNUC), and lastly, SMARCA4-deficient sinonasal teratocarcinosarcoma. These different tumor types display highly variable immunophenotypes with SMARCB1-deficient carcinomas showing variable squamous immunophenotype, while their SMARCA4-related counterparts lack such features altogether. While sharing same genetic defect, convincing evidence is still lacking that SMARCA4-deficient carcinoma and SMARCA4-deficient teratocracinosarcoma might belong to the spectrum of same entity. Available molecular studies revealed no additional drivers in these entities, confirming the central role of SWI/SNF deficiency as the sole driver genetic event in these aggressive malignancies. Notably, all studied cases lacked oncogenic IDH2 mutations characteristic of genuine SNUC. Identification and precise classification of these entities and separating them from SNUC, NUT carcinoma and other poorly differentiated neoplasms of epithelial melanocytic, hematolymphoid or mesenchymal origin is mandatory for appropriate prognostication and tailored therapies. Moreover, drugs targeting the SWI/SNF vulnerabilities are emerging in clinical trials.

The first case report of primary thyroid teratocarcinosarcoma: An analog to sinonasal teratocarcinosarcoma

Teratocarcinosarcoma is a rare and aggressive tumor usually affecting the sinonasal tract. It arises primarily from the nasal cavity, paranasal sinuses with some reported cases arising from the nasopharynx and oral cavity and commonly referred to as Sinonasal Teratocarcinosarcoma (SNTC). We present the first case of teratocarcinosarcoma as a primary thyroid cancer in a 17-year-old male patient who presented with a rapidly growing anterior neck mass with no symptoms. Physical examination revealed circa 4 cm × 5 cm slightly right sided, non-tender, firm anterior neck swelling. A thyroid ultrasound revealed an enlarged thyroid gland with multiple thyroid nodes. Magnetic Resonance Imaging (MRI) of the head and neck showed no sinonasal tract tumor. Thyroidectomy and surgical resection of the tumor was performed. Histological examination revealed teratocarcinosarcoma of the thyroid gland, an analog to SNTC with no primary sinonasal tissue involvement. This implies that, teratocarcinosarcoma can occur in primary tissues other than sinonasal origin contrary to conventional knowledge.

SALL-4 and Beta-Catenin Expression in Sinonasal Teratocarcinosarcoma

Sinonasal teratocarcinosarcoma (SNTCS) is a rare, aggressive malignancy that displays a heterogeneous combination of malignant blastema-like, epithelial and mesenchymal components. Its exact histogenesis is unknown with hypotheses ranging from true germ cell derivation to origin from pluripotent stem cells. However, despite this tumor's multiphenotypic histology, which includes frequent glandular, squamous, and neuroectodermal differentiation similar to adnexal germ cell tumors, SNTCS appears to have some differences from adnexal teratomas. For example, unlike adnexal teratomas, SNTCS has never been described as a component in a mixed germ cell tumor. Accurate recognition of SNTCS is difficult due to its rarity and histologic overlap with other sinonasal tumors. It is even more problematic on biopsy, since not all elements may be present in small samples. SNTCS can also share similar staining patterns with other neoplasms in the differential diagnosis. A recent study found nuclear β-catenin expression in a single TCS, but this has yet to be confirmed in additional cases. SALL-4, a marker of germ cell tumors, has not been examined. We performed β-catenin and SALL-4 immunohistochemistry on whole sections of 7 SNTCS and 19 other sinonasal neoplasms to assess whether β-catenin and SALL-4 are of utility in establishing a diagnosis of SNTCS. Intensity of expression and percentage of staining was noted for each tumor. For SNTCS, distribution of staining within each histologic component (immature neuroectodermal, epithelial, and mesenchymal) was also documented. Nuclear β-catenin expression was not identified in any SNTCS, with all cases demonstrating membranous expression (6 cases) or cytoplasmic and membranous expression (1 case). SALL-4 immunohistochemistry, however, was relatively sensitive (85.7%) and specific (89.5%) for SNTCS. SALL-4 expression was also identified in one poorly differentiated neuroendocrine carcinoma and one case of sinonasal undifferentiated carcinoma. SALL-4 appears to have utility in distinguishing SNTCS from other high grade sinonasal tumors.

SWI/SNF-deficient head and neck neoplasms: An overview

With wide-spread use of next generation sequencing tools in surgical pathology, a variety of neoplasms have been increasingly recognized to be associated with specific recurrent defining genetic abnormalities. This has led to recognition of new genetically defined entities and refinements of preexisting heterogeneous neoplastic categories. Among these, neoplasms associated with inactivating mutations involving different subunits of the SWI/SNF chromatin remodeling complex have received special attention. In the head and neck area, SMARCB1 (INI1) and SMARCA4 (BRG1) are the main two SWI/SNF components responsible for several recently described highly aggressive undifferentiated malignancies with predilection for the soft tissue of the neck (SMARCB1-deficient malignant rhabdoid tumors in children and rare epithelioid sarcoma cases in adults) and the sinonasal tract (SMARCB1-deficient sinonasal carcinoma including a small subset of adenocarcinomas, SMARCA4-deficient sinonasal undifferentiated carcinoma and SMARCA4-deficient sinonasal teratocarcinosarcoma). Molecular studies confirmed paucity of additional genetic abnormalities in these diseases underlining the central role of SWI/SNF deficiency as the primary and frequently sole genetic driver of these lethal diseases. Initiation of clinical trials using drugs that target the SWI/SNF collapse encourages recognition and correct classification of these morphologically frequently overlapping malignancies and underpins the role of SWI/SNF immunohistochemistry as emerging powerful adjunct tool in surgical pathology of the head and neck.

Malignant teratoid tumor of the thyroid gland: an aggressive primitive multiphenotypic malignancy showing organotypical elements and frequent DICER1 alterations-is the term "thyroblastoma" more appropriate?

Primary thyroid teratomas are exceedingly rare. Mature and immature variants recapitulate their gonadal counterparts (predilection for infants/children, triphasic germ layer differentiation, and favorable outcome). On the other hand, the so-called malignant teratomas affect predominantly adults and elderly, are highly aggressive, and, according to a few published cases, harbor DICER1 mutations. We describe three highly aggressive sporadic malignant teratoid thyroid tumors in 2 females (17 and 45 years) and one male (17 years). Histology showed triphasic neoplasms composed of solid nests of small primitive monomorphic cells embedded in a cellular stroma with primitive immature rhabdomyosarcoma-like (2) or pleomorphic sarcoma-like (1) phenotype. The third component was represented by TTF1+/PAX8+ primitive teratoid epithelial tubules reminiscent of primitive thyroid follicles and/or Wilms tumor, admixed with scattered respiratory- or enteric-type tubules, neuroepithelial rosettes, and fetal-type squamoid nests. Foci of cartilage were seen in two cases, but none contained mature organoid adult-type tissue or skin adnexa. SALL4 was expressed in the small cell (2) and stromal (1) component. Other germ cell markers were negative. Molecular testing revealed a known “hotspot” pathogenic DICER1 mutation in two cases. In addition, case 1 had a missense TP53 variant. This type of thyroid malignancy is distinct from genuine teratomas. The immunoprofile suggests primitive thyroid- or branchial cleft-like differentiation. Given that “blastoma” is a well-accepted terminology in the spectrum of DICER1-associated malignancies, the term “thyroblastoma” might be more convenient for these malignant teratoid tumors of the thyroid gland. Relationship of thyroblastoma to the DICER1 syndrome remains to be addressed.

Sinonasal Teratocarcinosarcoma, a Rare Tumor Involving Both the Nasal Cavity and the Cranial Cavity

Sinonasal teratocarcinosarcoma (SNTCS), a very rare tumor, is known to be a heterogeneous with epithelial, mesenchymal, and neuroepithelial components and shows a very aggressive clinical course. Due to the heterogeneity of this tumor, it is often misdiagnosed. No definitive treatment modality has been reported because it is a very rare tumor. A 44-year-old man presented to a rhinologist with headache and nasal obstruction, and an intranasal tumor was found that invaded into the cranial cavity. He underwent combined surgery with a rhinologist and a neurosurgeon following cognitive decline that worsened after a transnasal biopsy. The patient was diagnosed with SNTCS and underwent radiotherapy. However, residual tumor was found during radiotherapy and additional chemotherapy was administered. Follow-up brain MRI revealed no remnant or recurrent lesion. SNTCS is a tumor that has not yet been well researched and should be further investigated for proper treatment.

A unique uterine cervical "teratocarcinosarcoma": a case report

Background

Teratocarcinosarcoma (TCS) is a rare aggressive tumor of the nasal cavity and paranasal sinuses and has both epithelial and two or more mesenchymal components. In other organs, 5 cases of ovarian tumors closely resembling TCS have been reported; however, there has been no published case of cervical TCS. Herein, we describe a unique case of cervical tumor that had carcinosarcomatous and teratomatous features, resembling a sinonasal TCS.

Case presentation

A 45-year-old woman presented to our hospital for evaluation of a cervical lesion. The gynecologist found a large polypoid mass, whose biopsy showed glandular components of probable germ cell origin based on the immunohistochemical features. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy. The cervical polypoid mass was found to consist of both epithelial and mesenchymal tissues, including immature glandular structure resembling fetal enteric tubules, neuroepithelial cells, hyaline cartilage, and rhabdomyosarcoma cells. This tumor was diagnosed as TCS of the uterine cervix. Following the surgery, the patient received radiotherapy and has been free of disease for 13 months.

Conclusion

This is the first case report of cervical TCS. The tumor is thought to be histogenetically less associated with HPV infection, and its teratomatous components with an absence of cytogenetic abnormalities (including isochromosome 12p (i(12p)) suggest a analogous histogenesis compared to pure mature or immature teratoma.

Sinonasal teratocarcinosarcoma masquerading as an olfactory neuroblastoma

Sinonasal teratocarcinosarcoma (SNTCS) is a rare malignancy characterized by potent invasiveness, rapid growth, and a poor prognosis. Due to its diverse histopathological morphology, complex components, and insidious growth sites, as well as inadequate biopsies, SNTCS is often misdiagnosed as other tumors, and this misdiagnosis directly affects the treatment and prognosis of patients. Here, we report a case of an elderly SNTCS patient who underwent intranasal endoscopic tumor resection under systemic anesthesia. His preoperative diagnosis and intraoperative frozen sections both led to a misdiagnosis of olfactory neuroblastoma (ONB). However, after surgeries, the patient was diagnosed with SNTCS based on routine histopathology and immunohistochemical staining. He then underwent follow-up but died of tumor recurrence six months later.

Sinonasal Teratocarcinosarcoma- A Rare Tumour not so Rarely Misdiagnosed

Sinonasal teratocarcinosarcoma (STCS) is a rare, morphologically heterogeneous and highly aggressive tumour of ambiguous origin. It is characterized by the presence of benign and malignant epithelial, mesenchymal and neuroectodermal components. Because of their rarity and heterogeneity, these lesions are often misdiagnosed, leading to management difficulties. Adequate sampling with a high index of suspicion is needed to diagnose this rare tumour. We reported here a 48-year old man with right nasoethmoidal mass eroding the cribriform plate with intracranial extension. An initial incisional biopsy was performed and a diagnosis of craniopharyngioma was made. Subtotal endoscopic excision of the mass revealed features of STCS. Immunohistochemistry confirmed the same. The patient was subsequently treated with radiotherapy. The histogenesis, histopathological features, immunohistochemistry findings, clinical features and treatment were discussed here. Till date, there are less than 100 cases reported in English literature.

Sinonasal teratocarcinosarcoma: a clinicopathologic and immunohistochemical study of 6 cases

Teratocarcinosarcoma (TCS) is a rare and unusual malignant neoplasm of the sinonasal tract with a heterogenous morphology and an aggressive behavior. Patients are predominantly adults with a male predominance. The aim of this study was to describe clinicopathologic and immunohistochemical features of 6 cases of TCS. The ages ranged from 18 to 67 years (mean, 33 years) with a male-to-female ratio of 5:1. Most tumors were located in the nasal cavity. Nasal obstruction and epistaxis were the common presenting symptoms. Histologically, all tumors exhibited a heterogeneous morphology with varying proportions of benign and malignant epithelial, mesenchymal, and neuroepithelial elements. Adenocarcinoma was the malignant epithelial component in all cases. The mesenchymal elements were composed of benign to malignant spindle cells. Osteosarcomatous areas were seen in 2 cases and rhabdomyosarcoma in 1 case. Rhabdoid differentiation was also seen in 1 case. Immunohistochemical stains CKAE1/AE3 and CK Cam 5.2 were positive in the epithelial elements, vimentin in mesenchymal, and CD56 and neuron-specific enolase in neuroepithelial elements. Follow-up was available in 4 patients and ranged from 21 to 40 months (mean, 31 months). Lung and dura metastasis, respectively, were seen in 1 patient each. However, all 4 patients are alive and free of disease to date. In conclusion, TCS is a rare but highly malignant tumor with aggressive behavior characterized by benign and malignant epithelial, mesenchymal, and neuroepithelial components. Two patients in our series were younger than 20 years. The occurrence of rhabdoid differentiation and osteosarcomatous component seen in our series were rarely described in literature. Recognition of all the components requires adequate sampling, which is crucial for a correct diagnosis.

Sino nasal teratocarcinosarcoma-an interesting clinical entity

Sinonasal teratocarcinoma is a rare tumour of the paranasal sinuses. It was earlier termed as teratoid carcinosarcoma or teratocarcinoma. It is a highly aggressive tumour with a 5 year survival rate of 45 %. Here we report a case of sinonasal teratocarcinoma who was managed excision of tumour by lateral rhinotomy approach followed by radiotheraphy.

Intracerebral metastasis of a sinonasal teratocarcinosarcoma: a case report

Sinonasal teratocarcinosarcoma (SNTCS) is a rare, malignant neoplasm that contains both mesenchymal and epithelial components. The mortality rate for this tumor is ∼60% within 3 years, with the average survival rate being 1.7 years. Usually, this neoplasm presents with symptoms of nasal obstruction and epistaxis. Neurological symptoms from intracranial extension and dural invasion are rare presentations for this neoplasm. We present the first known case of an intracerebral metastasis of a previously resected SNTCS.

Chemotherapy-induced neuronal maturation in sinonasal teratocarcinosarcoma--a unique observation

Sinonasal teratocarcinosarcoma (SNTCS) is a rare and highly malignant tumour with combined features of a teratoma and carcinosarcoma. We report the first case of a SNTCS in 23 year old male treated with neo-adjuvant chemotherapy followed by cranio-facial resection. The resection specimen displayed cellular maturation in the neuroectodermal component. The patient presented with a short history of nasal obstruction, epistaxis and headache. On imaging, a bone destroying lesion of left paranasal sinuses and nasal cavity was identified. The diagnosis of SNTCS could be offered only on the third biopsy which showed heterogeneous admixture of primitive neuroectodermal, epithelial and mesenchymal elements. An adequate sampling with high index of suspicion is needed to catch hold this rare tumor. Tumor was excised after 4 cycles of neo-adjuvant chemotherapy. On microscopic examination, it showed similar epithelial and mesenchymal components as the pretreatment biopsies. However, the primitive neuroectodermal component displayed extensive neuronal maturation. The undifferentiated neuroectodermal cells were completely absent in the post chemotherapy specimen. This case throws light on the morphologic evidence of chemotherapy induced maturation in the neuroectodermal component within SNTCS, an event hitherto not reported in the literature in case of SNTCS.

Sinonasal teratocarcinosarcoma-A case report

Sinonasal teratocarcinosarcoma is a very rare tumor of ambiguous origin. Detailed examination of the biopsy material is essential for diagnosis. It is a very aggressive tumor with a five-year survival rate of 45%. Surgery with radiotherapy has been shown to be effective. We report a case of a 38-year old Indian gentleman with left nasoethmoidal mass eroding the cribriform plate with intracranial extension. Subtotal endoscopic excision of the mass revealed features of a sinonasal teratocarcinosarcoma. Immunohistochemistry confirmed the same. The patient was subsequently treated with radiotherapy. The clinical features, histopathological and immunohistochemistry findings and management of sinonasal teratocarcinosarcoma are discussed.