Solitary Pulmonary Capillary Hemangioma of Adult Cases: Clinicopathologic Characteristics as an Unrecognized Entity

A case of resected pulmonary capillary hemangioma with a literature review

Pulmonary hemangiomas are benign, relatively rare tumours. Because computed tomography (CT) findings show a variety of images, it is often difficult to distinguish hemangiomas from lung cancer and other benign tumours. We report a 63-year-old man who was diagnosed with a pulmonary capillary hemangioma (PCH). A right lung basal segmentectomy was performed for diagnosis and treatment. On chest CT, the lesion was shown to be a solid nodule with contrast-enhanced margins. This finding was thought to reflect the dense vascular hyperplasia of the central part of the tumour based on the pathologic findings. Although few studies involving PCH have referred to contrast-enhanced CT, the findings of contrast-enhanced CT might be a valuable indicator for diagnosing PCH.

Solitary Pulmonary Capillary Hemangioma: CT and PET-CT Features with Clinicopathologic Correlation

The aim of this study was to evaluate the CT and PET-CT features of solitary pulmonary capillary hemangioma (SPCH) with clinicopathologic correlations. This retrospective study included 17 patients with histologically proven SPCH from four tertiary institutions. The clinical, pathological and imaging findings of SPCH were reviewed. The CT features assessed included lesion location, size, density, contour, margin, enhancement, presence of air bronchogram, perivascular lucency and pleural retraction, and 18F-fluorodeoxyglucose uptake on PET-CT. Changes in the size during the follow-up period were also evaluated. Imaging features were correlated with the clinicopathologic findings. The mean age of the patients was 47 years (range 30–60 years). All SPCHs were incidentally detected during screening CT examinations (n = 13, 76%) or during cancer work-up (n = 4, 24%). Most SPCHs appeared as part-solid nodules (n = 15, 88%), the remaining appeared as a pure ground-glass nodule or a pure solid nodule, respectively. Most had smooth contours (n = 16, 94%), while one had a lobulated contour. Nine SPCHs (53%) showed ill-defined margins. Air bronchogram was present in ten (59%) SPCHs, and perivascular lucency in two (12%). All SPCHs exhibited hypoattenuation on contrast-enhanced CT and hypometabolism on PET-CT. During the follow-up period (mean 14.8 ± 17.7 months), the lesions showed no change in size or density in ten SPCHs (59%), decreased or fluctuation in size and density in three (18%). SPCH is often incidentally detected in young and middle-aged adults, commonly as an ill-defined part-solid nodule that may accompany air bronchogram, perivascular lucency, and fluctuation in size or density on CT and hypometabolism on PET-CT.

A radiomics model can distinguish solitary pulmonary capillary haemangioma from lung adenocarcinoma

OBJECTIVES

Solitary pulmonary capillary haemangioma (SPCH) is a benign lung tumour that presents as ground-glass nodules on computed tomography (CT) images and mimics lepidic-predominant adenocarcinoma. This study aimed to establish a discriminant model using a radiomic feature analysis to distinguish SPCH from lepidic-predominant adenocarcinoma.

METHODS

In the adenocarcinoma group, all tumours were of the lepidic-predominant subtype with high purity (>70%). A classification model was proposed based on a two-level decision tree and 26 radiomic features extracted from each segmented lesion. For comparison, a baseline model was built with the same 26 features using a support vector machine as the classifier. Both models were assessed by the leave-one-out cross-validation method.

RESULTS

This study included 13 and 49 patients who underwent complete resection for SPCH and adenocarcinoma, respectively. Two sets of features were identified for discrimination between the 2 different histology types. The first set included 2 principal components corresponding to the 2 largest eigenvalues for the root node of the two-level decision tree. The second set comprised 4 selected radiomic features. The area under the receiver operating characteristic curve, accuracy, sensitivity, specificity were 0.954, 91.9%, 92.3% and 91.8% in the proposed classification model, and were 0.805, 85.5%, 61.5% and 91.8% in the baseline model, respectively. The proposed classification model significantly outperformed the baseline model (P < 0.05).

CONCLUSIONS

The proposed model could differentiate the 2 different histology types on CT images, and this may help surgeons to preoperatively discriminate SPCH from adenocarcinoma.

Solitary pulmonary capillary hemangioma presenting with a ground glass opacity: A case report & literature review

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Solitary pulmonary capillary hemangioma (SPCH) is a rare benign lung tumor.

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SPCH presents with a ground glass opacity on CT scan.

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Preoperative definitive diagnosis as SPCH is a real challenge.

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Immunohistochemical staining is essential for diagnosis as SPCH.

Introduction

Solitary pulmonary capillary hemangioma (SPCH) is a rare benign lung tumor that clinically resembles early lung cancer and precancerous pulmonary lesions that present with similar imaging manifestations.

Presentation of case

The patient was a 54-year-old Japanese man who was referred to Nagara Medical Center with a ground glass opacity (GGO) lesion within the right upper lung that was incidentally detected on computed tomography. After 8 months of follow-up, video-assisted thoracoscopic segmental resection of the right upper lobe was performed with diagnostic and therapeutic intent. Pathologic examination of the resected specimen demonstrated thickening of the alveolar septum caused by the proliferation of capillary vessels. This lesion was positive for CD31 and CD34 and negative for thyroid transcription factor-1 and cytokeratin on immunohistochemical staining. The tumor was diagnosed as SPCH pathologically.

Discussion

When radiological examination demonstrates a GGO in the lung, SPCH must be considered as one of the differential diagnoses. For a definitive diagnosis, pathological examination of a surgically resected specimen must be conducted.

Conclusion

This study describes a case of SPCH and a review of the literature.

Progressively increasing density of the solid center of a ground-glass nodule in a solitary pulmonary capillary hemangioma: A case report

Solitary pulmonary capillary hemangiomas (SPCHs) are recently recognized, rare benign lesions that form solitary nodules owing to capillary proliferation. These lesions are usually detected incidentally as small ground-glass nodules (GGNs) on computed tomography (CT), and progressively enlarge over time. The radiological distinction from peripheral lung cancers is particularly challenging. However, to date, there have been no reports on progressive changes in the central density of SPCH on CT. An asymptomatic 49-year-old man was referred to our hospital for an abnormal shadow that was detected on chest CT during medical check-up. He was subsequently followed-up with chest CT. The nodule increased in size, and the central area became progressively denser. He underwent surgery 5 years and 10 months after the first visit owing to suspicion of lung cancer. Despite the collapse of the surgical specimen by artifacts, histopathological examination revealed a diagnosis of SPCH; collagenous fibers were found in the walls of the intralesional capillaries. The patient is presently alive without any recurrence, 6 months after the operation. In this case, the SPCH demonstrated a GGN with progressively increasing density of the central solid area on the CT. This remarkable feature made the preoperative distinction from lung cancer particularly difficult.

Intranodal capillary-cavernous hemangioma: Report of a very rare case

Mixed type capillary-cavernous hemangioma is a rare vascular anomaly, with an intranodal localization being extremely rare. Its finding is often accidental but may be clinically symptomatic. The diagnosis relies on histopathology, showing a proliferation of capillaries and cavernous vessels filled with erythrocytes and lined by endothelial cells. Magnetic resonance imaging with enhanced and T2 STIR sequences is the most efficient imaging for diagnosing this type of hemangioma. Rarely, malignancy or another vascular lesion can be evoked as a differential diagnosis of mixed hemangioma. Treatment in this localization is often surgical, even if other possibilities exist for other areas. In this article, we describe a very rare case of intranodal capillary-cavernous hemangioma.

Mesenchymal tumors of the lung: diagnostic pathology, molecular pathogenesis, and identified biomarkers

Lung cancers are mainly composed of epithelial tumors such as carcinomas. Since mesenchymal tumors that arise in the lung are very rare, they have garnered little attention. The 2015 World Health Organization (WHO) classification of lung tumors has undergone revision, not only for carcinomas but also for mesenchymal tumors. The current version now includes PEComatous tumors, myoepithelial tumors, and pulmonary myxoid sarcomas with EWSR1-CREB1 translocation as new disease entities. To date, no review article has comprehensively summarized what is known about pulmonary mesenchymal tumors in accordance with the latest WHO classification. In this review, we attempt to summarize the data about these tumors in line with the 2015 WHO classification (except for pediatric tumors), focusing on their diagnostic pathology, molecular pathogenesis, and identified biomarkers for differential diagnoses. We also address the recently recognized pulmonary mesenchymal tumors that have not yet been included in the WHO classification. An increased understanding of the molecular characteristics of pulmonary mesenchymal tumors has the potential to provide clinicians with the best therapeutic options for patients with these tumors.

Solitary pulmonary capillary hemangioma: Clinicopathologic and radiologic characteristics of nine surgically resected cases

BACKGROUND

Solitary pulmonary capillary hemangioma (SPCH) is an extraordinarily rare capillary derived mesenchymal neoplasm. Although routine morphology and immunohistochemistry are adequate for the diagnosis of classical SPCH in surgical specimens, true gross appearance identification of most tumor themselves and diagnosis for some exceptional cases are still very difficult. Furthermore, preoperative imaging and frozen diagnosis remain a challenge.

METHODS

We reported nine original cases of solitary pulmonary capillary hemangioma and summarized the clinical characteristics of twenty-one reported lesions. Imaging materials were reviewed by the image experts of our hospital. Quick hematoxylin-eosin stained intraoperative frozen sections and routine histological diagnosis were re-confirmed by 3 specialist pathologists with at least 10 years of diagnostic experience in our department. Immunohistochemistry analysis was performed on formalin fixed archival tissue. The surgical methods, following up information and prognosis were retrospectively analyzed.

RESULTS

In imaging, three tumors showed solid nodules, three cases displayed mix ground glass nodules, two nodules were pure ground glass density, and one case was a cystic-solid mass. Macroscopically, solitary pulmonary capillary hemangiomas were ill-defined soft hemorrhagic lesion with pale yellow or dark brownish cut surface. Two cases had a clear boundary and seven lesions were poorly demarcated. Typical morphological features were densely proliferating thin-walled capillaries composing of single layer of flatten or cuboidal endothelial cells within the thickened alveolar septa. One case was mistaken for a histiocytogenic lesion during freezing. The cystic-solid lesion showed a hyperplasia capillary network along the submucosal interstitium of bronchioles. Immunohistochemically, tumor endothelial cells were positive for ERG, Fli-1, CD31, CD34 and Vimentin and negative for CK, α-SMA, TTF-1, HMB45, S-100 and CD68. Lobectomy was performed on seven cases, wedge resection and segmentectomy were proceeded in two patients respectively. Follow up information showed no evidence of complication or recurrence.

CONCLUSIONS

Solitary pulmonary capillary hemangioma has special imaging and various histological features and must be distinguished from small benign lung lesions and preinvasive cancer. Although the prognosis of this tumor is good after surgical resection, the correct interpretation of the gross appearance and radiographic findings are still important. Choosing appropriate resection mode depends on accurate evaluation preoperative and intraoperative.

Solitary pulmonary capillary hemangioma: An under-recognized pulmonary lesion mimicking early lung cancer on computed tomography images

OBJECTIVES

Solitary pulmonary capillary hemangioma (SPCH) is a rare lung tumor typically presenting as pure or part-solid ground-glass nodules (GGNs) on computed tomography (CT), which clinically resembles early lung cancer.

MATERIALS AND METHODS

In addition to 10 recently diagnosed patients with SPCH, 71 benign lung nodules that were surgically resected between January 2013 and December 2017 were reviewed by thoracic pathologists to identify any previously unrecognized SPCH cases. Finally, 6 tumors (8.5%; 6/71) were determined to be SPCH. Elastic fiber stain (orcein stain) as well as immunohistochemistry for cytokeratin, CD31, and thyroid transcription factor 1 were performed for confirmation. Clinical and radiological data were analyzed.

RESULTS

All 16 SPCH lesions were unrecognized or misdiagnosed by general pathologists. The SPCH ranged in size from 3 to 15 mm, and a predominance among women (68.8%; 11/16) was noted. Pathologically, all SPCH lesions were nodular with a higher vascular density than the adjacent lung tissue. Decreased cytokeratin staining and disrupted elastic fibers were clearly observed in all SPCH lesions.

CONCLUSIONS

SPCH lesions mimic early lung cancer on CT; they are largely unrecognized by general pathologists and are diagnosed as other nonspecific benign lesions. With careful histologic examination, SPCH can be successfully diagnosed using cytokeratin/CD31 immunohistochemistry and elastic fiber staining.