Respiratory Epithelial Adenomatoid Hamartomas and Chondroosseous Respiratory Epithelial Hamartomas of the Sinonasal Tract: A Case Series and Literature Review

Seromucinous Hamartoma of the Lateral Nasal Wall with Infiltration of the Orbit: A Rare Case Report and Review of the Literature

Seromucinous hamartoma is a rare benign glandular proliferation arising from the respiratory epithelium of the sinonasal tract and nasopharynx. It was described for the first time in 1974 by Baillie and Batsakis. Since then, few cases have been reported in the literature with most of them occurring in the posterior nasal septum. We report the case of a 52-year-old woman that presented to our department with left periorbital edema, pain, and dacryorrhea due to seromucinous hamartoma arising from the left inferior turbinate and extending through the lateral nasal wall into the maxilla, the nasolacrimal duct, and the orbit. Endoscopic medial maxillectomy and endoscopic transnasal orbital tumor resection were performed. The patient remains symptom-free for 16 months, till her most recent follow-up. Seromucinous hamartoma of the nasal cavity is an exceedingly rare diagnosis, especially in the lateral nasal wall. It should be included in the differential diagnosis of nasal tumors. According to the literature review, this is the first case report of seromucinous hamartoma with orbit infiltration. Endonasal endoscopic resection is the treatment of choice.

Sinonasal Hamartomas: From Nasal Chondromesenchymal Hamartoma to Respiratory Epithelial Adenomatoid Hamartoma. Report of six Cases and Review of the Literature

Sinonasal hamartomas are uncommon lesions of nasal and sinus cavities. Based on indigenous cellular components and characteristic histologic features, they are further classified into four entities: respiratory epithelial adenomatoid hamartoma (REAH), seromucinous hamartoma (SH), chondro-osseous and respiratory epithelial hamartoma (CORE), and nasal chondromesenchymal hamartoma (NCH). REAH, SH, and CORE are seen in adult patients, while NCH predominantly occurs in newborns and infants. Morphologically REAH and SH are composed of respiratory epithelium and seromucinous glands, CORE is related to REAH but with additional feature of chondroid and/or osseous tissue, and NCH is composed of chondroid and stromal elements but devoid of epithelial component. All four lesions can present as sinonasal mass lesions and with associated obstructive symptoms. Given the rarity of these lesions, diagnosis can be challenging, especially in unusual clinical scenario. In this study, we report six cases of sinonasal hamartoma, including one case of NCH, one case of CORE, two cases of SH, and two cases of REAH. All cases were from adult patients including four men and two women. We also review the literature of the clinical and pathologic features of these rare lesions.

Immunohistochemical and genetic analysis of respiratory epithelial adenomatoid hamartomas and seromucinous hamartomas: are they precursor lesions to sinonasal low-grade tubulopapillary adenocarcinomas?

Respiratory epithelial adenomatoid hamartoma (REAH) and seromucinous hamartoma (SH) are rare tumor-like lesions of the nasal cavity, paranasal sinuses, and nasopharynx. The pathogenesis of REAH/SH is still unclear. Neoplastic proliferation, chronic mechanical irritation, inflammation, or possible embryological tissue misplacement are speculated as possible mechanisms of their development. Low-grade tubulopapillary adenocarcinoma (LGTA) is a rare variant of nonsalivary, nonintestinal type sinonasal adenocarcinoma. The aim of this study was to evaluate the immunohistochemical and genetic profiles of 10 cases of REAH/SH, with serous, mucinous, and respiratory components evaluated separately and to compare these findings with the features of 9 cases of LGTA. All cases of REAH/SH and LGTA were analyzed immunohistochemically with a cocktail of mucin antigens (MUC1, MUC2, MUC4, MUC5AC, MUC6) and with epithelial (CK7, CK20, CDX2, SATB2) and myoepithelial markers (S100 protein, p63, SOX10). The next-generation sequencing assay was performed using FusionPlex Solid Tumor Kit (ArcherDx) in 10 cases of REAH/SH, and the EGFR-ZNF267 gene fusion was detected in 1 of them. Two female REAH/SH cases were assessed for the presence of clonality. Using the human androgen receptor assay, 1 case was proved to be clonal. The serous component of REAH/SH was positive for CK7/MUC1 and SOX10 similarly to LGTA. Although REAH/SH and LGTA are histopathologically and clinically separate entities, the overlap in their morphological and immunohistochemical profiles suggests that REAH/SH might be a precursor lesion of LGTA.

Chondro-Osseous Respiratory Epithelial Adenomatoid Hamartoma (COREAH): Case Report and Literature Review

Chondro-osseous respiratory epithelial adenomatoid hamartoma (COREAH) is an extremely rare lesion of the nasal cavity with only 11 reported cases in the literature. COREAH is of interest as it may be easily mistaken for other diseases of the nasal cavity with higher morbidity, which require significantly different management strategies. We report, to the best of our knowledge, the oldest documented case of COREAH in the literature: an 83-year-old female who presented with headaches and was found to have a posterior nasal septal lesion. Uniquely, the patient had sequential scans performed 1 year apart demonstrating only minor interval growth. We describe our experience in managing a patient with COREAH and review the world literature, to better define aspects of the history, presentation, and investigations that may allow differentiation from more sinister disease.

Sinonasal Respiratory Epithelial Adenomatoid Hamartomas: Series of 51 Cases and Literature Review

Background

Respiratory epithelial adenomatoid hamartomas (REAHs) are rare, benign glandular proliferations of the nasal cavity, paranasal sinuses, and nasopharynx. This study aimed to expand our understanding of this entity by presenting a series of REAHs combined with a review of the pertinent literature.

Methods

A retrospective review was performed on all patients with a diagnosis of REAH from 2002 to 2011. Data were collected with respect to age, gender, clinical presentation, imaging, histopathology, treatment, and outcome. Because olfactory cleft expansion by imaging evaluation has been reported to suggest REAH, maximum olfactory cleft (MOCs) widths were also measured.

Results

Fifty-one cases of REAH included 37 male (72.5%) and 14 female subjects (27.5%) with a mean age of 58.4 years. Headache, nasal obstruction, rhinorrhea, and hyposmia were the most common presenting symptoms. Although 35(68.6%) were associated with concurrent inflammatory pathology, 16 (31.4%) presented as isolated lesions of the nasal cavity. Enlargement of MOCs was evident on computed tomography, with mean MOCs of 8.64 and 9.4 mm, in the coronal/axial planes, respectively. There were no statistically significant differences between MOCs of isolated (7.96 mm) versus MOCs of associated (9.63 mm) lesions (p = 0.25). Forty-nine were treated with endoscopic resection without evidence of recurrence after a mean follow-up of 27.2 months.

Conclusion

REAHs are rare sinonasal lesions that may appear as localized, isolated masses or more diffuse when in conjunction with other inflammatory processes. Irrespective of clinical presentation, endoscopic removal appears to be curative. Differentiation from more aggressive lesions is paramount to avoid unnecessarily radical surgery for an otherwise benign process.

Inverted Papilloma with New Bone Formation: Report of Three Cases

Background

An inverted papilloma (IP) is a benign sinonasal tumor of ectodermal origin, which is locally aggressive and destructive, tends to recur if incompletely removed, and has significant malignant potential. On CT scan, the appearance of an IP is variable and nonspecific but most commonly it appears to have soft tissue density. The association of IPs and new bone formation is extremely rare; to the best of our knowledge, only one case has been reported in the literature to date.

Methods

We report three cases with existence of bony mass surrounded by polypoid soft tissue diagnosed as IP histopathologically.

Results

The nature, shape, and location of the bony mass were not in concordance with trapped bone, with tumoral calcifications, or with osteoma.

Conclusion

We propose that with regard to the three cases presented here, new bone formation may be associated with IP pathologically. We also believe that additional investigations are required to characterize the pathophysiological mechanisms involved in neoplasm-induced osteogenesis.

Olfactory Epithelial Hamartoma: A New Subtype of Sinonasal Hamartoma

Sinonasal epithelial hamartomas occurring in adults are classified as seromucinous hamartoma (SMH) or respiratory epithelial adenomatoid hamartoma (REAH). We describe herein a novel subtype of adult sinonasal hamartoma that contains olfactory epithelium, a histologic feature not previously reported in the literature. Our pathology department database was retrospectively searched for sinonasal hamartomas containing areas of olfactory epithelium. Six relevant cases (3 male and 3 female patients; age, 30 to 77 y) were retrieved, and available pathology slides and clinical and imaging data from patient charts were reviewed. Five of the lesions were unilateral solitary, polypoid, pedunculated masses, 38 to 80 mm in length, lodged in the nasal olfactory cleft. The sixth lesion was associated with bilateral nasal polyposis, and its precise localization was not known. All patients were treated by transnasal endoscopic surgery. None of the 3 patients who had received adequate follow-up evaluation exhibited recurrence. Histologically, all lesions resembled SMH or REAH, with areas of olfactory epithelium comprising olfactory receptors and sustentacular and basal cells. Olfactory epithelium was observed at the lesion surface or in invaginated gland-like structures, and it contained focal aggregates of filamentous cell processes. Some olfactory receptor cells or cell processes were also present in the seromucinous gland component of lesions. Olfactory receptor cells expressed CD56 (neural cell adhesion molecule), and the filamentous aggregates contained CD56, neurofilaments, and synaptophysin. Aside from SMH and REAH, we have described a third subtype of adult sinonasal hamartoma-olfactory epithelial hamartoma-which shares the benign character of the other 2.

Respiratory Epithelial Adenomatoid Hamartomas: An Increasingly Common Diagnosis in the Setting of Nasal Polyps

Background

Respiratory epithelial adenomatoid hamartomas (REAH) are benign nose neoplasms found in the nasal cavity and sinuses. Symptoms include anosmia, nasal obstruction, facial pressure, and rhinorrhea. Although previously thought to be rare, these tumors are being increasingly recognized on pathology in patients undergoing endoscopic sinus surgery. However, REAH is difficult to diagnose before surgery because it may mimic other entities, such as nasal polyps or inverted papilloma, and is often found incidentally only after surgery.

Objective

The aims of this study were to (1) add an additional case series of REAH to the literature, (2) report unique imaging findings on computed tomography and magnetic resonance imaging, and (3) pool and summarize all available data from existing publications.

Methods

Retrospective chart review from years 2004 to 2015 and a literature review

Results

Twenty-three cases were found in our case series, which included 12 men (52%) and 11 women (48%), with a mean age of 59 years. No cases were found before 2007. Lund-Mackay scores were comparable with those found in chronic rhinosinusitis without nasal polyposis. Imaging consistently demonstrated a discoid-shaped mass at the olfactory cleft. Fifty previous publications were found (4 prospective, 11 retrospective studies, 9 case series, 26 cases reports), which included 660 patients diagnosed with REAH. Pooled data revealed a mean age of 54 years (range, 9–86 years) and a male to female ratio of 3:2.

Conclusion

The results of our study further refined the average age at which REAH diagnosis occurs as 54 years old, although it may occur at any age. There is a clear male-to-female predominance (3:2). In addition, olfactory cleft widening and discoid soft tissue at the olfactory cleft are hallmark radiographic findings. The vast majority of published cases occurred during the past 4 years, which indicated increased recognition of REAH.

Chondro-osseous respiratory epithelial adenomatoid hamartoma of the nasal cavity

Chondro-osseous respiratory epithelial adenomatoid hamartoma is a rare hamartomatous lesion of the nasal cavity, with only five cases reported in the literature to date. We report the case of a 3-year-old boy who presented with nasal obstruction and a mass in the left nasal cavity. The mass was completely resected on endoscopy. On microscopy, hamartomatous proliferation of respiratory-type glands admixed with islands of immature hyaline cartilage, characteristic of chondro-osseous respiratory epithelial adenomatoid hamartoma, was seen. Neither local recurrence nor distant metastasis was observed after 6 month follow up. Recognition of chondro-osseous respiratory epithelial adenomatoid hamartoma as a benign lesion is important to avoid unnecessary surgical procedures.

Nasal Cavity and Paranasal Sinuses

The nasal cavity and paranasal sinuses occupy the top of the upper respiratory tract and form pneumatic spaces connected with the atmosphere. They are located immediately beneath the base of the cranium, where crucial vital structures are harbored. From this region, very much exposed to airborne agents, arise some of the more complex and rare benign and malignant lesions seen in humans, whose difficulties in interpretation make this remarkable territory one of the most challenging in the practice of surgical pathology.

Contents of this chapter cover inflammations and infections, polyps and pseudotumors, fungal and midfacial destructive granulomatous lesions, as well as benign, borderline, and malignant neoplasms. Among the neoplasms, emphasis is made on those entities characteristic or even unique for the sinonasal region, such as Schneiderian papillomas, glomangiopericytoma, intestinal- and non-intestinal-type adenocarcinomas, olfactory neuroblastoma, nasal-type NK-/T-cell lymphoma, and teratocarcinosarcoma. Moreover, recently recognized entities involving this territory, i.e., HPV-related non-keratinizing carcinoma, NUT carcinoma, and SMARCB1-deficient basaloid carcinoma, are also discussed in the light of their specific molecular findings. Furthermore, the text is accompanied by numerous classical and recent references, several tables, and 100 illustrations.

Respiratory epithelial adenomatoid hamartoma of the nose: an updated review

BACKGROUND

This study was designed to update clinical and imaging features as well as treatment outcomes of the nasal respiratory epithelial adenomatoid hamartoma (REAH). Data sources included case reports, original articles, and reviews published in English or French in PubMed from 1995 to date.

METHODS

Only published articles that met Wenig's histological criteria for the diagnosis of REAH were included.

RESULTS

REAH is not rare and is probably underdiagnosed. It is usually observed in the fifth decade of life with a 3:2 male/female predilection. REAH can be represented in two forms: as an isolated lesion (less frequent) or in association with an inflammatory process (especially nasal polyposis). It was observed in 35-48% of patients undergoing endoscopic endonasal surgery for nasal polyposis. Its origin is found, in most cases, in the olfactory cleft, which is exhibited on computed tomography (CT) scans by widened opacified olfactory clefts without bone erosion. Resection of REAH from the olfactory clefts does not worsen, but instead, can improve the sense of smell after surgery.

CONCLUSION

Looking for REAH on CT scans and during endoscopic examination can lead to its diagnosis and help avoid aggressive surgical procedures and their complications. Endoscopic resection is the treatment of choice. The removal of REAH constitutes a specific surgery on the olfactory clefts, which can improve nasal obstruction as well as sense of smell. Whether REAH can be defined as a hamartoma, an inflammatory reactive process, or a neoplastic lesion remains to be determined.

Chondro-osseous respiratory epithelial adenomatoid hamartoma of the nasal cavity

Introduction: Chondro-osseous respiratory epithelial adenomatoid hamartoma (COREAH) is a benign lesion of the nose and sinuses that is extremely rare, with only 2 cases reported in the literature to date.

Case report: We present herein the third reported case of COREAH, in a 38-year-old woman who presented with left nasal obstruction and a mass in her left nasal cavity. The mass was completely resected endoscopically. Microscopic examination showed hamartomatous proliferation of respiratory-type glands with mucinous metaplasia admixed with numerous spicules of mature bone, characteristic of COREAH.

Conclusion: COREAH is a benign hamartomatous proliferation of respiratory epithelium, submucosal glands, and chondro-osseous mesenchyme. The clinical differential diagnoses for such lesions include glandular hamartoma, inflammatory polyp, inverted papilloma, and low-grade sinonasal adenocarcinoma. Recognition of this lesion as benign despite its potentially worrisome radiographic appearance is important to avoid an unnecessarily radical surgical procedure.

Seromucinous hamartoma of the nasal cavity: a report of two cases and review of the literature

The sinonasal tract is a complex anatomic site, home to a wide variety of reactive, inflammatory, benign, and malignant lesions. Inflammatory polyps and papillomas are usually easily recognized by pathologists. A poorly understood lesion that has been more clearly defined in recent years is the nasal hamartoma. The epithelial subtypes include seromucinous hamartoma, respiratory epithelial adenomatoid hamartoma, and hybrid lesions. Seromucinous hamartomas have only been recognized and substantially reported over the past few years. They are a diagnostic challenge, needing to be distinguished from low grade adenocarcinomas, and are of interest because most of the basic questions about their pathophysiology remain unanswered. Herein, we present two novel cases of seromucinous hamartoma with features that partly expand the morphologic spectrum of these lesions, discuss the differential diagnosis, and review the literature to compare our findings with previously reported cases with the aim of better understanding this interesting entity.

Nasal seromucinous hamartoma (microglandular adenosis of the nose): a morphological and molecular study of five cases

Five cases of nasal seromucinous hamartoma were studied and their clinical, morphological, immunohistochemical and molecular data are reported. The patients, three females and two males, ranged in age from 49 to 66 years (mean 56 year, SD ± 7.91). All lesions were located in the nasal cavity. In four cases where follow-up was obtained, no recurrence was evident. In all cases, numerous small seromucinous tubules, embedded in a cellular stroma, were present in the lamina propria. Tubules were lined by one layer of cuboidal cells which displayed luminal phenotype positive for lysozyme and EMA in four, and S100 protein in all cases. Collagen IV and laminin positive basal lamina outlined the tubules which lacked basal cells. Stromal spindle cells present among tubules were immunoreactive for calponin in all cases and for alpha-smooth muscle actin in four cases. DNA mutation analysis of mitochondrial D-loop region was performed by direct sequencing in order to verify the mutation rate of these lesions. The tubules of the five seromucinous hamartomas showed a higher mutation rate especially in heteroplasmy (0.52% homoplasmy, 2.02% heteroplasmy) in comparison to normal seromucinous glands which exhibited a lower mutation frequency (0.83%). This is considered a sign of a low cellular proliferation rate consistent with a benign process. It is concluded that nasal seromucinous hamartomas are benign glandular proliferations that may resemble microglandular adenosis of the breast. Their distinction from benign and malignant mimics is discussed.

Respiratory epithelial adenomatoid hamartoma in a dog

A 6-month-old, intact, male Weimaraner dog presented to the veterinary teaching hospital for bilateral mucopurulent ocular and nasal discharge that began at approximately 10 weeks of age. A computed tomography scan showed an expansile soft-tissue mass involving both frontal sinuses, the ethmoid regions, and nasal cavities with lysis of the maxillary turbinates and hyperostosis of the walls of the frontal sinus. The dog was euthanized after complications during a trephination and biopsy procedure. At necropsy, a large, tan, papillary, gelatinous mass filled the entire nasal cavity and frontal sinus. The mass was composed of large fronds of loose fibrovascular stroma covered by a single layer of pseudostratified, columnar, ciliated epithelium and intermixed goblet cells. The cells occasionally formed glandular structures that were continuous with the surface epithelium. The mass was diagnosed as a respiratory epithelial adenomatoid hamartoma based on the morphologic appearance.

Low grade glandular lesions of the sinonasal tract: a focused review

The sinonasal tract is a complex anatomic site with an exhaustive list of possible diagnoses. While most biopsies or resections encountered routinely consist of common diagnoses such as inflammatory polyps and papillomas, occasional cases are more difficult, and separating reactive or benign from malignancy can be challenging. One of the most poorly understood and daunting categories is low grade glandular or tubular proliferations, particularly on small biopsies. Possible diagnoses such as reactive lesions, respiratory epithelial adenomatoid hamartoma (REAH), seromucinous (glandular) hamartoma (SH) and low grade sinonasal adenocarcinomas (LGSNAC) must be entertained. REAH is composed of respiratory epithelial lined submucosal glands with variable connection to the surface and periglandular hyalinization. SH is a tubular proliferation reminiscent of normal serous glands which may be associated with REAH. LGSNAC is a diverse group of bland tubular and/or papillary tumors, which have a recurrence potential but an as yet uncertain potential for metastasis or mortality. The management for these lesions can be vastly different and conservative management is preferable, making this distinction more than academic. However, complicating this category are controversies surrounding their nature as reactive lesions versus neoplasms, the histologic and immunohistochemical overlap, and possible precursor relationships between some of them.

Selective pathologies of the head and neck in children: a developmental perspective

The range of pathology seen in the head and neck region is truly amazing and to a large extent probably mirrors the complex signaling pathways and careful orchestration of events that occurs between the primordial germ layers during the development of this region. As is true in general for the entire discipline of pediatric pathology, the head and neck pathology within this age group is as diverse and different as its adult counterpart. Cases that come across the pediatric head and neck surgical pathology bench are more heavily weighted toward developmental and congenital lesions such as branchial cleft anomalies, thyroglossal duct cysts, ectopias, heterotopias, choristomas, and primitive tumors. Many congenital "benign" lesions can cause significant morbidity and even mortality if they compress the airway or other vital structures. Exciting investigations into the molecular embryology of craniofacial development have begun to shed light on the pathogenesis of craniofacial developmental lesions and syndromes. Much more investigation is needed, however, to intertwine aberrations in the molecular ontogeny and development of the head and neck regions to the represented pathology. This review will integrate traditional morphologic embryology with some of the recent advances in the molecular pathways of head and neck development followed by a discussion of a variety of developmental lesions finishing with tumors presumed to be derived from pluripotent/progenitor cells and tumors that show anomalous or aborted development.

Seromucinous hamartomas: a clinicopathological study of a sinonasal glandular lesion lacking myoepithelial cells

AIMS

To describe seven cases of sinonasal seromucinous hamartoma.

MATERIALS AND RESULTS

The clinicopathological and immunohistochemical features of seven seromucinous hamartomas were analysed. There were four men and three women. Six lesions involved the posterior nasal septum and one the lateral wall. Size ranged from 6 to 40 mm. Four patients had no recurrences. One patient had local recurrences 24 and 60 months after diagnosis. The masses were covered by respiratory epithelium. Their stroma was oedematous to fibrous and contained invaginated respiratory epithelium forming glands and cysts, cysts with cuboidal to flat epithelium, and small serous glands, ducts and tubules with lobular and irregular haphazard patterns. One case had numerous glands surrounded by hyalinized basement membrane with features of respiratory epithelial adenomatoid hamartoma (REAH). One case had focal REAH-like changes. Both respiratory and serous components were positive for cytokeratin (CK) 7 and CK19. The serous component lacked myoepithelial cells when stained for CK14, p63, calponin and muscle-specific antigen in five cases.

CONCLUSIONS

Seromucinous hamartomas show a broader histopathological appearance than previously reported. The serous proliferation in these lesions lacks myoepithelial cells. The presence of occasional REAH-like features and common location in the posterior nasal septum suggest a spectrum from pure seromucinous hamartoma to REAH.

Respiratory epithelial adenomatoid hamartoma: a review

Respiratory epithelial adenomatoid hamartoma (REAH) is an uncommon lesion of the upper aerodigestive tract first described by Wenig and Heffner in 1995 as prominent glandular proliferations lined by ciliated respiratory epithelium originating from the surface epithelium. The entity is seen most often in male adults. Clinically the lesion presents as a polypoid mass, often in one or both nasal cavities, though other locations have been described. While REAH is benign, awareness and recognition of the lesion is important because it can be easily confused grossly and microscopically with more threatening tumors such as inverted papilloma and sinonasal carcinoma. The literature of REAH is reviewed with detail paid to the histologic diagnosis. The clinical presentation, radiologic findings, and differential diagnosis are also described.