THE "-OMAS" and "-OPIAS": Targeted and Philosophical Considerations Regarding Hamartomas, Choristomas, Teratomas, Ectopias, and Heterotopias in Pediatric Otorhinolaryngologic Pathology

Angiomyolipomatous Lesions of the Nasal Cavity (Sinonasal Angioleiomyoma with Adipocytic Differentiation): A Multi-Institutional Immunohistochemical and Molecular Study

PURPOSE

Mesenchymal neoplasms composed of vascular, smooth muscle, and adipocytic components are uncommon in the nasal cavity. While angioleiomyoma (AL) is a smooth muscle tumor in the Head & Neck WHO classification, it is considered of pericytic origin in the Skin as well as Soft Tissue and Bone classifications. For nasal AL with an adipocytic component, the terms AL with adipocytic differentiation and angiomyolipoma (AML) have been applied, among others. AML is a type of perivascular epithelioid cell tumor (PEComa), most often arising in the kidney, sometimes associated with the tuberous sclerosis complex (TSC). It is uncertain whether nasal cavity AML and AL are best considered hamartomas or neoplasms, as their genetics are largely unexplored.

METHODS

We performed a multi-institutional retrospective study of nasal cavity mesenchymal lesions. Patient demographics, clinical histories, and histologic and immunohistochemical findings were collected. DNA and RNA were extracted from formalin-fixed, paraffin-embedded tissue and analyzed by SNP-based chromosomal microarray, targeted RNA fusion sequencing, and whole-exome sequencing.

RESULTS

Fifteen lesions (3-42 mm) were identified, predominantly in male (87%) patients with a median age of 60. Patients typically presented with obstructive symptoms, and none had a history of TSC. One AL was a recurrence from six years prior; 11 cases showed no recurrence (median 4.7 years, range: 0.88-12.4). Morphologically, 11 AML contained 30-80% smooth muscle, 10-25% vasculature, and 2-60% adipose tissue, while four AL contained 70-80% smooth muscle and 20-30% vasculature. Other histologic observations included ulceration, thrombosis, inflammation, myxoid change, senescent nuclei, and extramedullary hematopoiesis; no well-developed epithelioid cell morphology was identified. Immunohistochemically, all cases were positive for smooth muscle markers (actin, desmin, and/or caldesmon) and negative for melanocytic markers. Molecular analysis revealed loss of 3p and 11q in a single AML. No other known pathogenic copy number or molecular alterations were seen, including in TSC1/2, TFE3, or NOTCH2.

CONCLUSION

Nasal cavity AML lacks morphologic, immunophenotypic, and genetic features of PEComa family AML. The significant histologic overlap between nasal AML and AL without distinguishing molecular features in either entity suggests "sinonasal angioleiomyoma with adipocytic differentiation" may be the most appropriate terminology for hybrid vascular and smooth muscle lesions containing adipocytic components.

Hamartomas, choristomas, and teratomas of the oral cavity: A 49-years cross-sectional study in an oral diagnostic service

BACKGROUND

To investigate the incidence and demographic profile of hamartomatous, choristomatous, and teratoid lesions in a Brazilian population over a 49 years-period.

METHODS

A retrospective cross-sectional study was performed, and data regarding demographic and clinical aspects were obtained from the medical records of a Brazilian referral center (1970-2019). The collected data were submitted to descriptive analysis and Pearson's chi-square, Fisher's exact, and Kruskal-Wallis tests (p ≤ 0.05).

RESULTS

In a total of 16,412 medical records analyzed, 300 (1.83 %) were hamartomatous, 2 (0.01 %) choristomatous, and 1 (0.01 %) teratoid lesions. Hamartomas were most diagnosed in females and adults. Statistical significance was observed between hamartoma and age group (p < 0.001). Odontoma was the most frequent hamartomatous lesion. In choristomatous and teratoid lesions, there was no occurrence in males. The jaws were the most affected anatomical site by hamartoma. Choristomas were observed on the mandible and tongue, while a teratoid lesion was seen on the floor of the mouth.

CONCLUSIONS

Low occurrence of choristomatous and teratoid lesions over hamartomatous lesions and a heterogeneous occurrence profile regarding sex, age group, and anatomic site were observed. Hamartomas are relatively common and benign conditions that may cause damage and require special care during dental treatment. Thus, the dentist needs to be able to identify and treat them appropriately. Likewise, although choristomas and teratomas present no risk to patients and have a lower occurrence than hamartomas, they also require treatment.

Angiomyolipomatous Lesions of the Nasal Cavity (Sinonasal Angioleiomyoma with Adipocytic Differentiation): A Multi-Institutional Immunohistochemical and Molecular Study

Purpose

Mesenchymal neoplasms composed of vascular, smooth muscle, and adipocytic components are uncommon in the nasal cavity. While angioleiomyoma (AL) is a smooth muscle tumor in the Head & Neck WHO classification, it is considered of pericytic origin in the Skin as well as Soft Tissue and Bone classifications. For nasal AL with an adipocytic component, the terms AL with adipocytic differentiation and angiomyolipoma (AML) have been applied, among others. AML is a type of perivascular epithelioid cell tumor (PEComa), most often arising in the kidney, sometimes associated with the tuberous sclerosis complex (TSC). It is uncertain whether nasal cavity AML and AL are best considered hamartomas or neoplasms, as their genetics are largely unexplored.

Methods

We performed a multi-institutional retrospective study of nasal cavity mesenchymal lesions. Patient demographics, clinical histories, and histologic and immunohistochemical findings were collected. DNA and RNA were extracted from formalin-fixed, paraffin-embedded tissue and analyzed by SNP-based chromosomal microarray, targeted RNA fusion sequencing, and whole-exome sequencing.

Results

Fifteen lesions (3 to 42 mm) were identified predominantly in male (87%) patients with a median age of 60. Patients typically presented with obstructive symptoms, and none had a history of TSC. One AL was a recurrence from six years prior; 11 cases showed no recurrence (median 4.7 years, range: 0.88-12.4). Morphologically, 11 AMLs contained 30-80% smooth muscle, 10-25% vasculature, and 2-60% adipose tissue, while four ALs contained 70-80% smooth muscle and 20-30% vasculature. Other histologic observations included surface ulceration, vascular thrombosis, chronic inflammation, and myxoid change; no well-developed epithelioid cell morphology was identified. Immunohistochemically, all cases were positive for smooth muscle markers (actin and/or desmin) and negative for melanocytic markers. Molecular analysis revealed loss of 3p and 11q in a single AML. No other known pathogenic copy number or molecular alterations were seen, including in TSC1/2, TFE3, or NOTCH2.

Conclusion

Nasal cavity AML lacks morphologic, immunophenotypic, and genetic features of PEComa family AMLs. The significant histologic overlap between nasal AML and AL without distinguishing molecular features in either entity suggests "sinonasal angioleiomyoma with adipocytic differentiation" may be the most appropriate terminology for hybrid vascular and smooth muscle lesions containing adipocytic components.

Case reports of oral choristomas and a review of the literature

Choristomas are proliferative growths that occur when normal tissue develops in abnormal locations and may resemble tumors. Oral choristomas commonly present as slow-growing, indolent, and firm masses. The diagnosis primarily relies on histopathologic examination. Given their tumor-like growth and developmental pathogenesis, it is critical to differentiate them from neoplasms. In this article, we present two clinical cases of oral choristomas, a cartilaginous choristoma, and an osseous choristoma of the tongue. We also offer a brief review of the literature discussing clinical presentation, microscopic features, and therapeutic options.

Oral Teratoma with Hairy Polyp-Like Features: A Brief Report of a Rare Presentation

We present a 21-day-old female child presenting with a large oral epithelialized tumor implanted at the rhinopharynx and ethmoid plate through a cleft palate, associated with feeding and respiratory difficulties. The histopathological exam showed mature central adipose tissue, hair follicles, sebaceous glands, and neurovascular structures, lined by keratinized stratified squamous epithelium. Proliferative cartilaginous, glandular, lymphatic, bony, and immature myxoid tissue was seen at the posterior region and insertion. Despite the characterization of the tumor as a teratoma containing structures derived from the three embryonic leaflets, the anterior portion presented a microscopic bigeminal pattern fully compatible with hairy polyp.

Lingual Choristoma with Gastric Epithelium Revisited

The term 'choristoma' refers to normal appearing tissue in an abnormal location. We describe a case of choristoma with gastric epithelium of the dorsal tongue in a pediatric patient. Lingual choristomas are uncommon cystic or solid lesions which may demonstrate different types of tissue (e.g. gastric epithelium, respiratory epithelium, osseous and neuroglial tissue) histologically. Choristomas with gastric epithelium, also known as heterotropic gastric mucosa or foregut duplication cysts, are thought to arise from pluripotential cells of the embryonic foregut. They most frequently involve the anterior two-thirds of the tongue. Most patients are asymptomatic, but larger lesions may lead to feeding and breathing difficulties. Pathologic evaluation and surgical excision remain the mainstay of diagnosis and treatment, respectively. The pathologic characteristics of other congenital tongue lesions are also discussed.