Solitary papillomas of the lower airways: epidemiological, clinical, and therapeutic data during a 22-year period and review of the literature. J Thorac Oncol. 2012;7:643-648. [PMID: 22425912 DOI: 10.1097/jto.0b013e3182468d06]

Clinical and imaging features of pulmonary mixed squamous cell and glandular papilloma: a case report and literature review

Pulmonary mixed squamous cell and glandular papilloma (MSGP) is a rare benign lung tumor with both squamous and glandular epithelial components. Reports on primary lung MSGP are few, and the aim of this study is to describe the imaging, including computed tomography (CT) and positron emission tomography (PET) findings, and histopathological characteristics of a case of MSGP in our hospital. A 53-year-old woman with no smoking history who underwent a chest CT scan revealed a nodule in the upper lobe of the left lung. The solid nodule showed no lobulation or spiculation but demonstrated significant enhancement on contrast-enhanced CT and increased fluorine-18 fluorodeoxyglucose (18F-FDG) uptake on PET. Moreover, a literature review identified 19 cases of lung MSGPs involving imaging findings, including CT and/or PET imaging. Except for one patient with a ground glass nodule, the rest were solid and ranged in size from 0.7 to 8.2 cm, which can present as a mildly to significantly increased 18F-FDG uptake on PET. MSGP is a rare benign tumor entity, and understanding its imaging findings and pathological immunohistochemical characteristics will help to improve the accurate diagnosis of MSGP so as to avoid unnecessary lobectomy and mediastinal lymph node dissection.

Bronchial Basaloid Papillary Tumor of Uncertain Malignant Potential: A Case Report

Bronchial papillomas are benign tumors, which can be divided into different subtypes based on the cellular features. So far, no bronchial papilloma with basaloid cell features has been reported. We report a bronchial basaloid papillary tumor in a 67-year-old woman. Tumor recurrence and malignant transformation were observed after a long-term follow-up. The clinical, histological, immunohistochemical, and genetic features were reappraised. The primary tumor was characterized by papillary growth pattern and basaloid neoplastic cells, only a small amount of neoplastic cells showed mature characteristics. The tumor originated from respiratory epithelium and had a low proliferation index by Ki-67. Keratin (KRT) 5/6 and KRT7 showed patchy or partial positivity. Myoepithelial markers were negative. P63 was diffusely positive, but it was negative in the small amount of tumor cells with mature characteristics. The common genetic alterations (EGFR, KRAS, BRAF V600E, HER2, and ALK) of lung cancers were not detected. However, tumor recurrence was observed in the mediastinum and esophagus 12 years after surgery. The recurrent tumor had a morphology overlapping with that of the primary tumor; however, it displayed significantly malignant characteristics. The recurrent tumor was not related to high-risk HPV. A high variant allele frequency was observed in tumor suppressor gene BRCA1, TP53, oncogene GNA11, and KIT, which were all missense mutations. Considering the bland features of the primary tumor and the fact of tumor recurrence and undisputed malignant transformation, the basaloid papillary tumor was considered a tumor with uncertain malignant potential.

Pulmonary pleomorphic carcinoma arising in mixed squamous and glandular papilloma: A case report

Solitary pulmonary papillomas (SPPs) are rare lung neoplasms. Histologically, SPP is classified into three subtypes, and mixed squamous and glandular papilloma (MP) is the rarest subtype. Although SPPs are considered benign tumors, there have been several reports on the synchronous malignant transformation in SPPs. An 82-year-old asymptomatic man was referred to our hospital for further examination of a 2.2 cm-sized left lung tumor. Pathology of bronchoscopic specimens showed the possibility of pulmonary papilloma but did not reveal any malignancy. The patient complained of bloody sputum during the eighth month after the initial visit. The size of the lesion had increased to 4.3 cm. These data suggested the existence of malignancy, and the patient underwent an operation. Histologically, the tumor was composed of fibrovascular cores and papillomatous fronds lined by pseudostratified columnar cells and mucin-filled goblet cells. Keratinizing squamous epithelium was also observed. Overall, the diagnosis of MP was obtained by fundamental histology. In addition, a solid part beneath mild atypical squamous epithelia, which was composed of malignant-appearing squamous cells and spindle-shaped atypical cells, was observed. The spindle portion was positive for cytokeratin AE1/AE3 and vimentin, and focally positive for alpha-smooth muscle actin (αSMA). The final diagnosis was pulmonary pleomorphic carcinoma (PPC) arising in the MP. Only two cases have been reported for atypical spindle tumor cells that are found in MP or bronchiolar adenoma/ciliated muconodular papillary tumor (BA/CMPT), which has histologically similar features to MP. This is the second case report of PPC arising in MP.

FDG PET/CT in a Case of Solitary Mixed Squamous Cell and Glandular Papilloma of the Lung With High CEA Level

ABSTRACT

Solitary mixed squamous cell and glandular papilloma of the lung is an extremely rare benign neoplasm. We describe FDG PET/CT findings in a case of solitary mixed squamous cell and glandular papilloma of the lung with high serum carcinoembryonic antigen level (63.3 ng/mL; reference, <5 ng/mL). The tumor showed intense FDG uptake with SUVmax of 23.8 mimicking lung cancer.

Endobronchial Glandular Papilloma With Atypical Histologic Characteristics: A Case Report and Literature Review

Papilloma of the lung is a rare benign entity and can be solitary or multiple. Solitary papilloma is subclassified into three categories: squamous papilloma, glandular papilloma, and mixed squamous and glandular papilloma. Glandular papilloma is the rarest subtype among them and occurs mostly in the sixth decade without any relation to smoking, syndrome, or infection. Histology is characterized by mixture of pseudostratified, columnar, nonciliated, mucinous epithelium-lined papillary fronds without any mitoses, necrosis, or atypia. The differential diagnosis can be broad depending upon the histologic features present in a particular case and may include both benign and malignant entities. We present here a patient with glandular endobronchial papilloma showing unusual clinical history and atypical histologic features, which required extensive immunohistochemical evaluation to establish a final diagnosis.

Slowly Growing Pulmonary Glandular Papilloma with Air Bronchogram: A Case Report

Pulmonary glandular papilloma is a rare benign neoplasm that has not been studied extensively. This neoplasm presents as a solid nodule, consolidation, or mass, with or without atelectasis, and assessing the correlation between these findings and the risk of malignancy is challenging. A 60-year-old woman presented a solitary pulmonary nodule on screening chest radiography and chest computed tomography (CT). During the subsequent 2-year follow-up, CT showed a progressive increase in nodule size and an air bronchogram, suggesting malignancy. The patient underwent a right upper lobectomy, and the final diagnosis was glandular papilloma. Teaching point: Pulmonary glandular papilloma with growth and an air bronchogram.

Mixed squamous cell and glandular papilloma of the lung increased in twelve years -A case report

We report the case of a 55-year-old man presented with a nodule in the right middle lung on computed tomography. The size of the nodule had increased at 12 years after the first visit. Consequently, the patient was diagnosed with a Mixed squamous cell and glandular papilloma (MSGP) by surgical resection. To our knowledge, there are no previous studies that MSGP in the lung which had been observed for 12 years before surgery. This study reports the case of a patient who underwent surgical resection of a MSGP.

Pulmonary mixed squamous and glandular papilloma: diagnostic challenges of a rare lesion when the clock is ticking. How to avoid interpretation mistakes

Pulmonary mixed squamous and glandular papillomas (MSCGPs) are rare, benign neoplasms with peculiar clinical and histological features. However, on occasion, they can present certain characteristics that overlap with other neoplasms including carcinomas. Recognising these features is hence important for treatment purposes. Molecular studies can sometimes help in further characterisation, although they should not guide the diagnosis which ultimately relies on morphology.

We report a challenging case of MSCGP with unusual features, received during intraoperative consultation. We highlight the subtle morphological features to help avoid overcalling a benign lesion as malignant.

Clinicopathological feature of a resected large mixed squamous cell and glandular papilloma: A case report

Introduction and importance

Solitary endotracheal papilloma is a rare benign lung tumor. It is classified into the following three histological subtypes: squamous cell papilloma (SP), glandular papilloma (GP), and mixed squamous cell and glandular papilloma (MSGP). MSGP is the rarest among them. Herein, we describe a case of a large MSGP.

Case presentation

A 59-year-old woman underwent computed tomography for the examination of cough, and an 8.2-cm-sized lung mass was noted in the left lingual segment. Bronchoscopy revealed that the left B⁵ lumen was completely occluded by a tumor. Transbronchial lung biopsy suggested GP; thereafter, a left upper lobectomy was performed. Macroscopic findings showed that the dilated B⁵ lumen was filled with cauliflower-like tumors. Histopathological findings showed that the majority of the tumors had pseudostratified columnar epithelium, while some had stratified squamous epithelium. The patient was diagnosed with MSGP. Although koilocytosis-like changes, such as perinuclear halo and nuclear deformation, were observed in some portions of the squamous epithelium, immunohistochemical staining was negative for human papillomavirus (HPV).

Clinical discussion

HPV infection is reportedly associated with SP but not with GP and MSGP. Therefore, MSGP is considered to be caused by squamous metaplasia of a part of GP; this hypothesis is consistent with the present case. However, only one case of MSGP with HPV infection was recently reported, and the etiology and histological features of MSGP remain unclear.

Conclusion

There are few reported cases of MSGP, and further case reports are needed to clarify its pathogenesis.

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Human papillomavirus (HPV) infection is related to squamous cell papilloma.

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HPV infection is not related to mixed squamous cell and glandular papilloma (MSGP).

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MSGP is caused by squamous metaplasia of glandular papilloma.

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Accumulation of more case reports on MSGP is required to elucidate its pathogenesis.

Multiple Primary Lung Tumors of Different Pathological Types Including Squamous Cell Carcinoma, Adenocarcinoma, and Mixed Squamous Cell and Glandular Papilloma: A Case Report

Multiple primary lung cancer (MPLC) is considered relatively rare. This report presents an unusual case of multiple pulmonary nodules in a 74-year-old man who presented with three independent synchronous tumors in the right upper lobe. The tumors were diagnosed as peripheral squamous cell carcinoma (SCC), adenocarcinoma, and pulmonary mixed squamous cell and glandular papilloma (mixed papilloma). Mixed papilloma is an extremely rare, benign pulmonary tumor with a typical papillary appearance, showing squamous and glandular epithelial differentiation. The histological and immunohistochemical features of each tumor were analyzed. In addition, molecular pathological examination for epidermal growth factor receptor (EGFR) showed no mutation in two primary cancers. Mixed papilloma showed no BRAF V600E mutation or HPV infection. The present case report provides a clinicopathological understanding of an instance in which three tumors of different pathological types are present in the same lung lobe. Furthermore, it provides a literature review regarding multiple lung nodules, focusing on the clinicopathological diagnosis, clinical treatment, and prognostic assessment of these nodules. This is the first case report of mixed papilloma arising in MPLC.

Pulmonary peripheral glandular papilloma and mixed squamous cell and glandular papilloma frequently harbour the BRAF V600E mutation

AIMS

Pulmonary peripheral glandular papilloma (GP) and mixed squamous cell and glandular papilloma (MP) have very similar histological features to pulmonary ciliated muconodular papillary tumour (CMPT)/bronchiolar adenoma (BA). The underlying genetic relationships between GP/MP and CMPT/BA have rarely been characterised. We aimed to reveal the relationship between them.

METHODS AND RESULTS

We performed a clinicopathological review and next-generation sequencing (NGS) study of two GPs and five MPs. Histologically, GPs/MPs showed similar cellular and architectural features to CMPTs/BAs, such as bilayered epithelium, bronchiole-associated lesions and skipping (discontinuous) growth pattern. One MP showed partial and inconspicuous endobronchiolar growth and more glandular structures, which was very similar to the appearance of CMPT/BA. BRAF V600E mutation was detected in four papillomas (57.1%, one GP and three MPs).

CONCLUSIONS

Overlapping morphological features and comparable mutation profiles support that peripheral GPs/MPs and CMPTs/BAs are on the same disease spectrum. We propose expanding the concept of CMPT/BA and including GP and MP in the CMPT/BA family.

Diagnosis and management of glandular papilloma of lung: A case report

BACKGROUND

Solitary respiratory papilloma is a rare epithelial tumor that can be categorized into multiple subtypes depending on tumor location, histological presentation and number. The glandular type is the rarest, with only 30 cases available within the field. Hence, information on its identification and treatment is limited. In this report, we discuss the diagnostic strategy and management of glandular papilloma, along with a review of the literature.

CASE SUMMARY

We describe a male 44-year-old nonsmoker who presented with a persistent cough and recurrent pneumonia, which he had experienced for over 2 years. A solitary pulmonary nodule with an endobronchial lesion was found via computed tomography of the chest. After a biopsy was obtained, no definite diagnosis could be made. Glandular papilloma of the lung was confirmed via video-assisted thoracoscopic anatomic resection of the right lower lobe of the lung. The patient remained disease-free after 6 mo follow up.

CONCLUSION

Minimally invasive surgery is feasible for the surgical resection of endobronchial glandular papilloma. Although rare, glandular papilloma should be considered in patients with infection or endobronchial lesions.

Mixed squamous cell and glandular papilloma of the lung-A case report and literature review in Japan

INTRODUCTION

Mixed squamous cell and glandular papilloma (MSGP) of the lung is rare neoplasm, only 19 cases previously reported in Japan. MSGP is one of three separate categories of solitary endobronchial papillomas, which account for less than 0.5 % of all lung tumors. MSGP is rarest of the three. We present a rare case of MSGP and review the literature in Japan.

PRESENTATION OF CASE

A 49-year-old man presented with a nodulous shadow in the right lower lung field identified on a chest X-ray performed for back pain. Computed tomography demonstrated a well-circumscribed, 9-mm mass in the S8 segment of the right lower lung lobe. Positron emission tomography showed accumulation of 18F-fluorodeoxyglucose in the tumor with a standardized uptake value of 2.29. Following thoracoscopic partial resection, adenocarcinoma was diagnosed by frozen section, and radical segmentectomy of S8 was performed. The final diagnosis was mixed squamous cell and glandular papilloma. The patient had an uncomplicated postoperative course and remains asymptomatic 3 years after the procedure.

DISCUSSION

The etiology and pathological characteristics of MSGP remain unclear. There has been no report of recurrence in MSGP cases treated with complete resection; thus, limited resection that preserves pulmonary function is desirable. Further data including new cases are required.

CONCLUSION

We present a rare case of mixed squamous cell and glandular papilloma (MSGP) of the lung and review the literature in Japan. Limited resection that preserves pulmonary function, while ensuring complete resection, is desirable. Further investigations with new cases are required.

Solitary glandular papilloma of the lung with molecular analysis: A case report and literature review

BACKGROUND

Solitary papillomas of the lung are rare. One of their subtypes is glandular papilloma with only a very few cases described in the literature. We describe a case of pulmonary glandular papilloma with emphasis in its differential diagnosis and its molecular analysis.

CASE DESCRIPTION

A 64-years old former smoker was incidentally found to have an endobronchial tumor of the right main bronchus. Microscopic and immunohistochemical findings revealed a glandular papilloma. EGFR, KRAS and BRAF V600E mutation analysis, as well as HPV detection analysis revealed no mutation or HPV infection. Detailed differential diagnosis and literature review are presented.

CONCLUSION

Glandular papillomas of the lung are usually central, affecting older patients than squamous or mixed squamous cell and glandular papillomas. In previously reported cases, one glandular papilloma with KRAS mutation and another one with BRAF mutation have been reported. The present case harbored no mutation or HPV infection.

Adenocarcinoma-Papillary Cystic Pattern Arising in a Mixed Squamous and Glandular Papilloma of the Lung

Mixed squamous and glandular papilloma (mixed papilloma) of the lung has been reported in fewer than 25 cases in the English literature. Although it is known as a benign tumor, malignant transformation has been reported. Papillary cystic carcinoma is characterized by papillary and cystic growth patterns and has been reported as a subtype of adenocarcinoma, mainly in the salivary glands, breast, and pancreas. In this article, we report a case of adenocarcinoma-papillary cystic pattern arising from mixed papilloma of the lung in a 76-year-old male patient. Chest computed tomography scan revealed an endobronchial mass growing at the right medial segmental bronchus. Middle lobe lobectomy was performed, revealing a 4.9 × 1.9 cm-sized mass that protruded into the bronchus. Microscopically, the tumor showed numerous cysts lined by micropapillary projections. The tumor cells had round and vesicular nuclei with prominent nucleoli, and mitosis was frequent. A limited portion of the tumor consisted of benign mixed papilloma. The tumor showed diffuse immunoreactivity for thyroid transcription factor-1 and strong expression of p16. We investigated the mutational status of cancer-related genes using targeted next-generation sequencing and identified a genetic alteration in the BRAF gene. This is the first case report of papillary cystic carcinoma arising in mixed papilloma of the lung.

A 17-year-old woman with a solitary, mixed squamous cell and glandular papilloma of the bronchus

A 17-year-old woman was referred to our hospital due to cough on exertion and right chest pain over the previous two months, together with bloody sputum over the previous week. Chest X-ray demonstrated a nodule measuring 3 cm in diameter in the right middle lung field. On repeated bronchoscopy, the tumour was recognized as a rapidly growing intra-bronchial protruded tumour at the orifice of the right B8. Based on a tentative diagnosis of lung cancer, right lower lobectomy was performed. She was diagnosed with mixed squamous cell and glandular papilloma of the bronchus without smoking history and human papillomavirus infection. Solitary endobronchial papillomas are rare but should be considered a differential diagnosis for solitary lung nodule with the potential to develop into carcinoma.

Mixed squamous cell and glandular papilloma of the lung: A case report of a novel mutation in the BRAF gene and coexistent HPV infection, possible relationship to ciliated muconodular papillary tumor

Mixed squamous cell and glandular papilloma (mixed papilloma) is a very rare tumor, with fewer than 25 cases having been reported in the literature. Although a scattering of cases of p16^Ink4a overexpression have been described to date, no human papillomavirus (HPV) DNA has been detected in these tumors, either by in situ hybridization (ISH) or polymerase chain reaction (PCR). This is the first case of mixed papilloma with PCR-confirmed HPV genotype 16, 35, 51 infections in an 18-year-old non-smoking male, coexisting with multiple atypical adenomatous hyperplasias (AAHs). Histologically, this tumor shows a predominant papillary architecture, covered by a mixture of stratified squamous cells, ciliated or non-ciliated cuboidal to columnar cells, mucous cells, and scattered goblet cells. Immunohistochemically, the squamous component was positive for p40, and the glandular cells were focally positive for TTF-1. Both components were diffusely immunoreactive to CK7. In addition, BRAF V600E mutation was also first demonstrated in mixed papilloma, but not in the AAHs. These findings suggest that HPV infection and the BRAF mutation may be important in the pathogenetic role in young non-smoking patients.

A unique case of a huge mixed squamous cell and glandular papilloma of non-endobronchial origin with a peripheral growth

We report a case of a huge solitary non-endobronchial pulmonary tumor in a 76-year-old male smoker. The tumor measured 11 × 10 × 8 cm. It was ill-defined, and it was located periphery of the right lower lobe with the subpleural cystic spaces. He underwent right lower lobectomy with mediastinal lymph node dissection and is free from tumor 30 months after surgery. Microscopically, it was composed of a proliferation of squamous and ciliated columnar epithelial cells with a few mucous cells. These cells were arranged in a papillary growth fashion extending along the fibrously thickened alveolar septa together with metaplastic bronchiolar and squamous epithelia displaying an usual interstitial pneumonia-pattern. Although the histologic features of the tumor were that of a mixed squamous cell and glandular papilloma (MSCGP), it was peripherally located and showed a lepidic growth, and it was much larger than previously reported MSCGPs. It is possible that the tumor developed in association with bronchial metaplasia in the periphery of the lung, and then extended along the surface of the reconstructed air spaces, which resulted in its unique histologic appearance. Further investigations of respiratory papilloma are needed to clarify the pathogenesis of these lesions.

Solitary Endobronchial Papilloma with Malignant Transformation and Concomitant TB Infection: Case Report and Literature Review

We are reporting a case of solitary endobronchial papilloma located in posterior segment of the left upper lobe of the lung with malignant transformation and negative human papilloma virus (HPV) strains in a 40-year-old Saudi nonsmoker man. The patient had a concomitant tuberculosis (TB) infection. The patient received appropriate treatment in the form of anti-TB medication and surgical resection of the squamous cell carcinoma followed by chemotherapy. There was no evidence of tumor recurrence, resulting in a complete cure. We are reporting the case as well as a literature review related to the topic.

Tracheobronchial tumors

Tumors of trachea and bronchi are uncommon and can occur in the form of benign or low- and high-grade malignant tumors. Although tracheobronchial tumors (TBTs) represent only 0.6% of all pulmonary tumors, they are clinically significant. Delays in diagnosis of these tumors commonly occur because the signs and symptoms caused by these tumors are nonspecific and chest radiographs are often considered unremarkable. Therefore, novel radiological techniques and better access to flexible bronchoscopy enable detection of larger number of TBT. The purpose of this article is to provide a review of tracheal and bronchial tumors and discuss significant aspects of the different TBT with focus on clinical manifestations and diagnostic procedures.

Respiratory papillomas

Papillomas are known to occur in the lower respiratory tract. They are however, rare compared to their occurrence in the upper respiratory tract. These are generally exophytic tumors in the more proximal upper airways however cases with more distal location with an inverted growth pattern have also been described in the literature. These can be solitary or multiple and multifocality associated with multiple papillomas in the upper respiratory/aerodigestive tract. The four major types of respiratory papillomas are (1) Recurrent respiratory papillomas, (2) solitary squamous papillomas, (3) solitary glandular papillomas, (4) mixed papillomas. We review the incidence, etiopathology, diagnosis, and possible treatment modalities and algorithms for these respiratory papillomas.

Mixed squamous cell and glandular papilloma of the lung resembling early adenocarcinoma: A case report

Introduction

An extremely rare case of mixed squamous cell and glandular papilloma of the lung is reported. The correlation between the radiological and the pathological features as well as the clinical pitfall in making a diagnosis is discussed.

Presentation of case

An asymptomatic 68-year-old female with a cigarette smoking habit presented with a small nodule in her peripheral lung. A wedge resection was performed though it failed on-site diagnosis which was instead obtained following pathological scrutiny. The postsurgical course was excellent with no recurrence of disease.

Discussion

A small ground glass nodule gradually enlarged and transformed to a partially solid nodule a year and a half later. This transformation falsely made us suspect an early adenocarcinoma development. Eventually, the extremely rare subtype of pulmonary papilloma, with biphasic glandular and squamous cells, had been demonstrated to obstruct the peripheral bronchiole; and the adjoining alveoli had filled with a large volume of mucus. These pathological features seemed to have constituted the inner solid portion and the marginal ground glass portion respectively in the CT images, mimicking invasive lepidic adenocarcinoma.

Conclusion

Both pre- and intra-operative diagnoses are difficult mainly because of the rareness of the disease, however, mixed squamous cell and glandular papilloma may be considered in case the presence of primary adenocarcinoma is not validated.

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Mixed squamous cell and glandular subtype is extremely rare pulmonary papilloma.

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Initial presentation of this benign tumor had resembled early adenocarcinoma.

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This disease should be taken into account in making a differential diagnosis.

Ciliated muconodular papillary tumor: a solitary peripheral lung nodule in a teenage girl

Papillary tumors of the peripheral lung containing ciliated cells and extracellular mucin include solitary peripheral ciliated glandular papilloma, ciliated muconodular papillary tumor, and well-differentiated papillary adenocarcinoma with cilia formation. We report the case of a 19-year-old woman who was a nonsmoker and presented with an incidental small peripheral lung nodule. The resection specimen showed a soft grayish nodule. Histologic examination further revealed a relatively circumscribed mucinous nodule featuring a tubulopapillary tumor composed of ciliated columnar cells and goblet cells, accompanied with abundant extracellular mucin. No lepidic growth pattern was evident. The tumor cells were immunoreactive for cytokeratin 7, thyroid transcription factor-1, and carcinoembryonic antigen, whereas p63 and cytokeratin 5/6 highlighted the presence of basal cells. Next-generation sequencing did not identify any genetic alterations in targeted regions and mutational hotspots of a panel of 22 genes commonly implicated in lung and colon cancers. Taken together, our case was most likely a ciliated muconodular papillary tumor.

Rapidly growing glandular papilloma associated with mucus production: a case report

Background

Pulmonary glandular papillomas are rare neoplasms, and their very slow or absent growth over time generally facilitates establishing the diagnosis.

Case presentation

In an 84-year-old woman who underwent surgery for sigmoid colon cancer, a growing solitary pulmonary nodule was identified on postoperative follow-up computed tomography. A computer tomography-guided needle biopsy was performed under suspicion that the nodule was malignant. The histopathological findings suggested a glandular papilloma. Right basilar segmentectomy was carried out, and the lesion was completely resected. Postoperative histopathological examination revealed a benign glandular papilloma accompanied by mucus retention in the surrounding alveolar region.

Conclusions

A malignant neoplasm is usually suspected when a pulmonary tumor shows rapid growth. However, glandular papillomas associated with mucus retention also tend to grow in some cases, and should be included in the differential diagnosis.

Solitary glandular papilloma of the peripheral lung: a report of two cases

Solitary papilloma of the lung is thought to be a rare benign epithelial tumor, and complete surgical resection is currently the standard treatment for this pathology. However, some cases of papilloma have reportedly shown malignant potential. We report two cases of solitary glandular papilloma of the peripheral lung that were treated by thoracoscopic partial resection. The first patient presented with a nodular lesion in the lower lobe of the left lung that was detected on a follow-up chest computed tomography (CT) scan after treatment for laryngeal cancer. Partial lung resection was performed by video-assisted thoracoscopic surgery. In the second patient, a nodular lesion was incidentally identified in the lower lobe of the left lung during a health check-up. Partial lung resection was again performed by video-assisted thoracoscopic surgery. The postoperative course in both cases was uneventful, and no recurrences have been observed as of 44 months and 41 months postoperatively, respectively. To the best of our knowledge, malignant transformation has been reported both with the squamous type and the mixed type of solitary papilloma of the lung. The glandular variant has shown no tendency toward local recurrence after local excision and has no apparent malignant potential. Local excision is thus recommended for solitary glandular papilloma in order to preserve pulmonary function.

Mixed squamous cell and glandular papilloma of the lung in a 64-year-old woman

Mixed squamous cell and glandular papilloma of the lung is an extremely rare benign epithelial tumor showing a mixture of squamous and glandular epithelium. Here, we report a case of mixed squamous cell and glandular papilloma that presented as a solitary nodule in the left lower lobe of a 64-year-old woman. Chest computed tomography demonstrated a lobulated mass in the basal segment of the left lower lobe. The patient underwent a lobectomy under the suspicion of lung malignancy. The histopathological diagnosis was mixed squamous cell and glandular papilloma.

Pulmonary mixed squamous cell and glandular papilloma mimicking adenocarcinoma: a case study and literature review

Mixed squamous cell and glandular papilloma of the lung is an extremely rare benign neoplasm. Here we present another case of mixed squamous cell and glandular papilloma in a 64-year-old female nonsmoker. Histologically, the tumor was composed of mainly papillary structures covered with squamous, glandular and transitional epithelium. Some glandular structures extending into adjacent bronchiolar and alveolar spaces with mucus were similar to adenocarcinoma. Immunohistochemical analysis showed the different kinds of epithelia had similar immunophenotype. The different components were positive for cytokeratin (CK)7, CK19, CAM5.2, CK5/6, CK34βE12, and TTF-1, but negative for CK20. The transitional morphology and immunohistochemistry indicate the different components likely come from a same kind of progenitor in the bronchiolar wall.