Histogenesis of intrapulmonary and endobronchial hamartomas and chondromas (cartilage-containing tumours): a hypothesis

Pulmonary leiomyosarcoma arising in pulmonary hamartoma: an exceptional occurrence in a rare tumor

A solitary peripheral lung nodule was found in the left lung of a 52-year-old man. It was located in the lower lobe and measured 18.5 cm of major axis on chest computed tomography. A tru-cut core biopsy was obtained and a proliferation of bland, monomorphic, spindle cells in interlacing fascicles was observed. Accordingly, a surgical resection of the neoplasm was subsequently carried out. Macroscopically, the tumor appeared as a well-circumscribed nodule with a firm and whitish cut surface. Histologically, the neoplasm was predominantly composed of bland and monomorphic spindle cells, with a predominantly fascicular growth pattern, in which many tubular and cleft-like spaces of entrapped normal respiratory epithelium were involved. Myxoid change, stromal hyalinization and scattered bizarre mononucleated and multinucleated cells were also observed. Based on clinico-morphological, immunophenotypical and molecular features, we made a diagnosis of malignant transformation of pulmonary adenoleiomyomatous hamartoma into pulmonary leiomyosarcoma. As far as we know, this is the first described case of this exceptionally rare occurrence in an already rare neoplasm.

Benign tumours of the bronchopulmonary system

The vast majority of tumours arising in the bronchopulmonary system are malignant in nature. Benign tumours of the lung are relatively rare and are often incidental findings during clinical investigations for unrelated conditions. These lesions can arise in the bronchial tree or the pulmonary parenchyma and may be of epithelial, mesenchymal, salivary gland-type or unknown differentiation. Although the spectrum of these lesions is wide, the clinical, pathological and immunohistochemical characteristics of the most relevant will be the subject of this review. In addition, the most important features allowing differentiation from malignant pulmonary neoplasms will be discussed.

Hamartomas and other tumor-like malformations of the lungs and heart

Tumor-like malformative lesions are seen throughout the body, and they may be confused with true neoplasms by clinicians and pathologists alike. In the lungs, they are principally represented by hamartomas-which may contain chondroid, adipocytic, fibroblastic, and myxoid tissue, with entrapped bronchiolar epithelium-and congenital pulmonary airway malformations (CPAMs). The latter have been subdivided into 5 groups, based on their histological features, but they basically comprise proliferations of malformed bronchopulmonary tissues of different types. Type 1 lesions have a capacity for malignant transformation in a small proportion of cases. Malformative cardiac tumefactions include rhabdomyoma-like hamartomas; fibromatous hamartomas; and mesenchymal ventricular hamartomas, which contain cardiac muscle, smooth muscle, fat, vasogenic tissue, and nerves. Another intracardiac proliferation in the same general category is seen in the interatrial septum, in the region of the atrioventricular node. It comprises randomly-disposed gland-like profiles that are made up of endodermal epithelium. Originally thought to be a form of mesothelial lesion, that abnormality is now classified as an endodermal choristoma. All forms of pulmonary and cardiac malformations are only rarely symptomatic, and the necessity for surgical excision of them depends on the particular details of each case.

Computed Tomography Imaging Findings of Pulmonary Chondroma

PURPOSE

To characterize the computed tomography (CT) imaging findings in patients with pulmonary chondroma.

METHODS

We examined CT imaging findings of eight patients with histopathologically verified pulmonary chondroma. We assessed the location, size, shape, margins, amount of calcification, calcification pattern, and attenuation on precontrast and enhancement CT.

RESULTS

All patients exhibited solitary, mildly lobulated pulmonary masses, which were located in the right lung in four cases and the left lung in four cases. The mean lesion size was 3.7 cm (range 0.9-10.7 cm). All eight tumours had a well-defined margin. On plain CT images, seven of the cases (87.5%) showed a mass with varying degrees of calcification, which included strip-like punctate (n=5) and ring (n=2) patterns. One patient with a large lesion (10.7 cm) showed chest wall adhesion. On contrast-enhanced CT images, all lesions demonstrated slight inhomogeneous enhancement ≤14 HU.

CONCLUSION

CT is the reference standard diagnostic technique for locating pulmonary chondroma. In most cases, CT findings show some characteristics that are important in the diagnosis, surgical planning, and follow-up of the tumour.

Pulmonary chondroma: A clinicopathological study of 29 cases and a review of the literature

The present retrospective study was designed to review the clinicopathological features and outcome of surgical treatment of pulmonary chondroma, and to accumulate data for the clinical diagnosis and therapy. The clinicopathological data from 29 patients, aged between 38- and 78-years-old, with pulmonary chondroma who underwent surgical operation between July 2003 and June 2015 were reviewed. Of these patients, 18 exhibited no clinical symptoms, 7 were characterized by coughing, hemoptysis, shortness of breath and other symptoms and only 3 patients exhibited chest pain as the predominant symptom. The average size of the neoplasms was 3.6 cm. All patients were pathologically diagnosed. Operative time was 126±22 min, the mean intraoperative blood loss was 82±23 ml and the drainage duration was 3.1±1.8 days. A total of 6 postoperative complications were noted. The patients were followed-up for 2–135 months. A total of 23 patients were alive without recurrence, 4 patients succumbed to mortality, 2 patients were lost at follow-up. Pulmonary chondroma is a rare benign tumor of the lung. The clinical symptoms were concealed and often misdiagnosed as a tuberculosis tumor, hamartoma, peripheral lung cancer or a single metastatic tumor. Complete resection was the best treatment providing patients with a good prognosis. After definite diagnosis, it is necessary to exclude Carney's triad.

A case of tracheal hamartoma resected with loop electrocautery

The authors report on the case of a 67-year-old man with longstanding breathlessness, which was eventually attributed to a fixed mass in the upper third of the trachea causing upper airway obstruction. The lesion was amenable to loop electrocautery resection via flexible bronchoscopy that led to prompt resolution of patient symptoms. Biopsy was consistent with tracheal hamartoma, an exceedingly rare benign tracheal tumor. All the cases of tracheal hamartomas in the literature to date, the application of electrocautery and other methods of interventional bronchoscopy for resection of selected tracheal tumors are discussed.

A case of bilateral multiple pulmonary chondroma: necessity of follow-up for Carney's triad

We report a case of pulmonary bilateral multiple chondromas that were possibly an initial clinical presentation of Carney's triad. A 56-year-old Japanese non-smoking asymptomatic woman was admitted to the hospital for further examination of small, multiple, bilateral nodules in the lungs. Although chest radiological findings suggested that the nodules were possibly metastatic pulmonary tumors, the malignant origin was not detected. During diagnostic video-assisted thoracic surgery, wedge resections including the nodules were performed. Since pathological examination showed nodules were surrounded by fibrous and eosinophilic stroma, we diagnose the nodules as chondromas. These chondromas were possibly components of Carney's triad, because each nodule had a thin fibrous pseudocapsule and did not have an entrapped epithelium and fat. Some patients die of Carney's triad because of malignant alteration of lesions. Therefore, the patients with Carney's triad should be taken a medical check periodically. This patient was scheduled to undergo the check-up for several years.

Extrapulmonary hamartoma

We describe a rare case of extrapulmonary hamartoma. A 65-year-old man underwent video-assisted thoracic surgery to obtain a histological diagnosis of a tumor with an irregular shape in the subpleural region of the right apical segment. Thoracoscopy showed a chondromatous tumor in the extrapleural region. The tumor resection was uneventful. Pathology study showed a hamartoma outside the visceral pleura.

Dedifferentiated chondrosarcoma of the lung: report of a case

This report presents a rare case of pulmonary sarcoma with regional anaplastic changes. A 73-year-old Japanese man with a hamartoma-like nodule of the left lung accompanied by interstitial pneumonia was followed up for 30 months. He underwent a surgical resection due to the rapid growth of the lung nodule. A pathological examination revealed a dedifferentiated sarcoma arising from the chondrosarcoma.

Mesenchymal cystic hamartoma of the lung: MRI and PET/CT appearance

We report the magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) findings of a patient who presented with lower thoracic pain, nausea, and vomiting and had a CT scan of the chest in which a well-defined homogeneous mass was identified. Further evaluation with MRI and PET/CT showed a nonenhancing homogeneous paraspinal mass in the left lung base involving the left hemidiaphragm. The mass showed lack of enhancement on MRI and was photopenic on PET/CT. Video-assisted thoracoscopic surgery and resection of the mass was performed and showed a mesenchymal cystic hamartoma invading the left hemidiaphragm. Such a growing hamartoma with pleural and diaphragmatic invasion is very atypical and to our knowledge, has not been previously reported.

Dedifferentiated chondrosarcoma of the lung: case report and review of the literature

Primary malignant chondromatoid tumors of the lungs are rare. We report on a case of a 49-year-old woman who presented with a round focus in the upper lobe of the left lung. The performed biopsy showed features of a leiomyosarcoma. After chemotherapy and consecutive tumor resection, the histologic investigation of the entire tumor mass revealed a dedifferentiated chondrosarcoma. Careful clinical and radiologic examinations showed no evidence of further pulmonary and extra-pulmonary tumor lesions. The final diagnosis of a primary dedifferentiated chondrosarcoma of the lung was based on the morphologic criteria and review of the literature. The differential diagnosis of malignant hamartoma was discussed. Follow-up investigation after 2.5 years showed no evidence of another primary tumor site.

Gastrointestinal stromal tumours (GISTs): a clinicopathological and molecular study of 66 cases

AIMS

Predicting the clinical behaviour of gastrointestinal stromal tumours (GISTs) is difficult and criteria delineating benign from malignant cases are not firmly established. The aims of this study were to define the clinicopathological and molecular features of 66 GISTs, and to determine whether any specific parameters were associated with patient outcome.

METHODS

Archival cases of GIST from two major teaching hospitals in Western Australia were studied. Inclusion criteria for the study were: (1) appropriate morphology, (2) CD117 positivity, (3) adequacy of pathological material for study, and (4) exclusion of other tumour types on the basis of immunophenotypic and/or ultrastructural features. Expression of CD117, CD34, S100 protein, keratin (using broad spectrum MNF116), alpha-smooth muscle actin (SMA) was determined by immunohistochemistry. PCR and single strand conformation polymorphism (PCR-SSCP) analysis were used to screen for mutations in exons 11 and 9 of c-kit.

RESULTS

There were equal numbers of males and females with a mean age at diagnosis of 60 years, followed up for a mean of 54 months. Thirteen patients (21%) had died of GIST by the end of the study. Tumours were mostly located in the stomach (67%) and small intestine (SI; 25%). The cell types were pure spindle (68%), pure epithelioid (12%) and mixed epithelioid/spindle (20%). c-kit mutations were found in 69% of GISTs, with the large majority (91%) occurring in exon 11. Size > or = 10 cm, tumour necrosis and pure epithelioid cell morphology each were the only factors significantly associated with adverse survival (p=0.038, and p=0.047 and p=0.028, respectively). Mitotic activity > or = 5/50 HPF showed a definite trend association with adverse survival, but unlike some other studies, did not achieve statistical significance (p=0.067). c-kit mutations were more frequent in small intestinal GISTs (p=0.05) and in those with pure spindle cell morphology (p=0.023) but were not associated with patient outcome.

CONCLUSION

In this study, size > or = 10cm, necrosis and/or pure epithelioid cell morphology correlated significantly with adverse survival. Mitotic activity showed a strong association with survival but this did not reach statistical significance. c-kit mutations occurred mainly in GISTs of the SI, and in purely spindle cell tumours. While the mutation status did not associate with patient outcome in this series, this remains a controversial issue, and further studies are needed to assess whether the type of mutation affects response to tyrosine kinase inhibitor therapy in metastatic GISTs. CD117 staining of any mesenchymal lesion of the gastrointestinal tract should be mandatory for accurate classification. PCR-SSCP analysis is a fast, sensitive and relatively inexpensive method of analysing c-kit mutations, which may be important prognostically and also of therapeutic relevance in the assessment of new tyrosine kinase inhibitor therapies.

Atypical lipomatous tumour (lipoma-like well-differentiated liposarcoma) arising in a pulmonary hamartoma and clinically presenting with pneumothorax

We document an uncommon variant of pulmonary hamartoma (PH), discovered in the left upper lobe of a 60-year-old man after an episode of pneumothorax, a unique clinical presentation for such an occurrence. The tumour showed a prominent leaf-like pattern and was mainly composed of mature fat with adipocytes of different size and scattered throughout lipoblasts and floret-like cells. A lobectomy was performed and more than 7 years after surgery the patient's course is still uneventful. This case represents an exceedingly rare example of an histologically malignant change in PH and bears a close clinicopathologic resemblance to atypical lipomatous tumours of soft tissues.

Spontaneous pulmonary neoplasms in cynomolgus monkeys (Macaca fascicularis)--a report of two cases

The first lung tumour-bearing animal was a 7 years and 3 months old cynomolgus monkey. Microscopic examination revealed a neoplastic mass under the pleura that consisted of squamous islands with little keratinization, multifocal mineralization of the keratin, inflammatory cell and foreign body-type giant cell infiltration. It was classified as pulmonary squamous cell carcinoma. In a second cynomolgus monkey (2 years and 10 months old) a lung mass was observed at necropsy. Microscopically the tumour consisted of numerous islands of cartilage with glandular structures lined by a cuboidal epithelium between them. The neoplasm was classified as cartilaginous hamartoma.

Multiple chondromatous hamartomas of the lung: a case report and review of the literature with special reference to Carney syndrome

BACKGROUND

Multiple chondromatous hamartomas of the lung, which are very rare, are a feature of Carney syndrome. The relation between the two entities is not clear.

METHODS

A patient with multiple chondromatous hamartomas of the lung is described in this article. The literature was reviewed with special reference to the relation between multiple chondromatous hamartomas of the lung and Carney syndrome as well as the triad of gastric epithelioid leiomyosarcoma, functioning extra-adrenal paraganglioma, and pulmonary chondroma.

RESULTS

A total of 15 cases of multiple chondromatous hamartomas of the lung have been published worldwide. Two cases exhibited two other features of Carney syndrome, namely, gastric leiomyogenic neoplasms and extra-adrenal paragangliomas, and three other cases demonstrated only gastric leiomyomatous neoplasms. These five patients were all young females.

CONCLUSIONS

Some patients with multiple chondromatous hamartomas of the lung have a history of Carney syndrome. Patients with multiple chondromatous hamartomas require further examination of other sites, particularly the stomach and nervous system.

Gastric stromal sarcoma, pulmonary chondroma, and extra-adrenal paraganglioma (Carney Triad): natural history, adrenocortical component, and possible familial occurrence

OBJECTIVE

To investigate the natural history of the triad of gastric stromal sarcoma, pulmonary chondroma, and extra-adrenal paraganglioma, a rare syndrome of unknown cause primarily affecting young women.

METHODS

Mayo Clinic records, the world literature, and the author's files were searched for patients with all or 2 of the 3 tumors.

RESULTS

Seventy-nine patients, 67 women and 12 men, were identified, 17 (22%) with the 3 tumors and 62 (78%) with 2 tumors. Forty-two (53%) had gastric and pulmonary tumors, the most common combination. The longest interval between detection of the first and second components was 26 years (mean, 8.4 years; median, 6 years). Follow-up ranged from 1 year to 49 years (mean, 20.6 years; median, 20 years). Sixty-four patients (81%) were alive, 19 (24%) apparently free of disease and 45 (57%) with residual or metastatic tumors. Thirty-two patients (41%) had had 1 or more local recurrences of the gastric sarcoma; the longest interval to first recurrence was 36 years. Twenty-one survivors (27%) had hepatic metastatic gastric sarcoma with follow-up of 1 year to 25 years (mean, 9.3 years; median, 7 years). Fifteen patients (19%) were dead, 10 (13%) of whom died of the disorder. Ten patients (13%) had nonfunctioning adrenocortical tumors. Two patients each had a sibling with 1 component of the triad.

CONCLUSIONS

The triad is a chronic, persistent, and indolent disease. Benign adrenocortical tumors are a component of the condition. The disorder may be familial.

Pathological and radiological correlation of endobronchial neoplasms: Part I, Benign tumors

Benign endobronchial lung neoplasms are extremely rare. Most such neoplasms are of mesenchymal origin; however, neoplasms of submucosal gland origin and surface epithelial origin also occur. The symptomatology and radiographic features of these tumors are often indistinguishable from those of malignant lung tumors. However, recognition and early diagnosis of these lesions may allow for conservative treatment and excellent patient outcome. The clinicopathologic and radiological features of these pulmonary neoplasms are discussed.

Peripheral intrapulmonary hamartoma accompanied by a similar endotracheal lesion

We describe a case of peripheral intrapulmonary hamartoma accompanied by a similar endotracheal lesion. A 70-year-old asymptomatic man had a polypoid lesion in the trachea and a nodular shadow in a peripheral lung area. A biopsy specimen from the trachea revealed a chondroid hamartoma, and the surgically resected tissue of the intrapulmonary tumor showed the same histologic findings. This is the second case of multiple hamartomas showing coexistence of tracheobronchial and parenchymal tumors.

Pulmonary adenofibroma: report of two cases of an unusual type of hamartomatous lesion of the lung

We report two cases of a primary lung tumour characterized by complex gland-like spaces lined by simple cuboidal to columnar epithelium surrounded by a hyalinized spindle-cell fibroblastic proliferation reminiscent of adenofibromas of the female genital tract. The lesions occurred in a 54-year-old woman and a 56-year-old man. The tumours presented clinically as 1-2 cm, solitary 'coin' lesions and were discovered incidentally on routine chest X-rays. Both lesions were treated by lobectomy. One patient is alive and well with no evidence of disease after 8 years; the other died of myocardial infarction 5 years following resection of his tumour without evidence of recurrence. We interpret these lesions as benign hamartomatous growths; their main importance lies in distinguishing them histologically from other types of pulmonary hamartomas, pulmonary blastomas, intrapulmonary solitary fibrous tumours, and metastases from soft tissue and visceral sarcomas.

Multiple recurrent intrapulmonary and endobronchial mesenchymomas (hamartomas)

A patient is described with multiple, benign, chondromatous intrapulmonary and endobronchial mesenchymomas of the lung, which recurred after resection on two occasions over a period of 30 years. In such a patient presenting at a young age or with a history of previous recurrence, a wedge excision may be necessary to prevent further recurrence.

Multiple cystic pulmonary hamartomas

A patient with multiple cystic hamartomas presented with a pneumothorax and later developed a cystic myxomatous vaginal polyp. This and three of the cysts were resected. She remains well 13 years later. Multiple cystic hamartomas are uncommon and may be misdiagnosed as pulmonary metastases.

Massive congenital mesenchymal malformation of the lung: a case report with ultrastructural study

An unusual congenital tumorous malformation of mesenchymal tissue caused severe respiratory distress in a premature infant. The solid mass, which replaced almost the entire left lung, was composed of interlacing fascicles of spindle cells that percolated through otherwise well-developed fetal lung tissue. The normal anatomic arrangement of bronchial components was altered, but bronchial cartilages were present. Ultrastructural study of the lesion showed mesenchymal cells with fibroblastic differentation.

Primary pulmonary neoplasms of childhood: a review

Primary tumors of the lung rarely occur in children. However, 230 well-documented cases, including the 2 presented in this review, have been identified in the English-language literature. One hundred fifty-one tumors in these reports were classified as malignant lesions and 79 as benign neoplasms. Bronchial "adenomas" constituted the largest group; most of these lesions were of the carcinoid variety, and 8% were definitely malignant. Forty-seven cases of bronchogenic carcinoma were reported in children under 16 years of age, although there were few squamous cell tumors (12%). Fifty-six percent of the benign tumors were classified as inflammatory pseudotumor. Most of the children in this collective series were seen with symptoms related to bronchial irritation or obstruction, such as cough, hemoptysis, atelectasis, or pneumonitis. Respiratory distress was an unusual symptom that was often associated with large tumors seen in the neonatal period. Approximately 20% of the children were totally symptomatic. The limited survival data that are available indicate that leiomyosarcoma and mucoepidermoid carcinoma have a more favorable prognosis in children than in adults. Survival with bronchial carcinoid tumors (90%), bronchogenic carcinoma (30%), and pulmonary blastoma (45%) appears to parallel that for adults. The experience with pulmonary rhabdomyosarcoma, as described in this review, emphasizes the importance of early diagnosis and the use of combined modes of therapy in the approach to these malignancies. Despite the rarity of primary pulmonary neoplasms in children, this diagnosis should be considered in young patients with solitary pulmonary masses or persistent, atypical pulmonary symptoms. It is hoped that early diagnosis will result in an improved prognosis and prevent life-threatening complications.

Clinical spectrum of pulmonary hamartomas

Pulmonary hamartomas are tumors that occur in the parenchyma or the bronchi. Through the lesions themselves are benign, they may be associated with malignant neoplasms or they may cause obstruction of the bronchi because of their location. Pulmonary hamartomas were resected in 29 patients at the Ochsner Medical Institutions during a 30-year period. Of these patients, 6 had symptoms related to concomitant malignancy and 3 had symptoms resulting from obstruction of the bronchi by the hamartoma. Surgical treatment ranged from enucleation to pneumonectomy. One patient died in the hospital of extensive bronchogenic carcinoma. In 2 others, carcinoma of the lung developed within twelve months after resection of a hamartoma. In this group of patients, 20% had concomitant or subsequent pulmonary lesions. Ten percent of the hamartomas were located in the bronchi, resulting in bronchial obstruction. A surgical approach is indicated for lesions that appear to be pulmonary hamartomas on roentgenograms.

Uncommon pulmonary hamartomas

Three cases are reported--one endobronchial hamartoma, one endobronchial hamartoma accompanied by a similar intrapulmonary lesion, and one multiple hamartoma. These cases typify the clinical presentation and illustrate some of the difficulties in diagnosis and management. The published cases are reviewed.