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

Frequent PIK3CA and GNAQ mutations in solitary pulmonary capillary haemangioma and pulmonary cavernous haemangioma: genetic link to vascular malformations

Pulmonary haemangiomas are rare diseases with unclear pathogenesis. The molecular alterations underlying these conditions have not yet been identified. In this study, we sought to investigate the genetic alterations in the two most common types of pulmonary haemangiomas: solitary pulmonary capillary haemangiomas (SPCH) and pulmonary cavernous haemangiomas. This study included six patients with SPCH and four patients with pulmonary cavernous haemangioma. Utilising a customised next-generation sequencing panel, we identified a high frequency of PIK3CA hotspot mutations-five of six SPCH cases and three of four pulmonary cavernous haemangiomas, totalling 80%. Additionally, GNAQ mutations were detected in one SPCH and one pulmonary cavernous haemangioma. Overall, nine of 10 (90%) of the pulmonary haemangiomas in our study harboured mutations in either the PIK3CA or GNAQ genes. The variant allele frequencies of these mutations were relatively low, ranging from 4.2% to 15.5%, which complicates detection using Sanger sequencing due to its lower sensitivity. Our study identified a high frequency of PIK3CA mutations and occasional GNAQ mutations in SPCH and pulmonary cavernous haemangioma. The high prevalence of PIK3CA mutations in pulmonary haemangiomas suggests a potential link to the vascular malformation category in the International Society for the Study of Vascular Anomalies (ISSVA) classification where PIK3CA mutations are recognised as significant causative genetic events. The findings from this research represent the first documented evidence of the molecular alterations underlying these pulmonary haemangiomas.

Solitary pulmonary capillary hemangioma - An underrecognized rare tumor. Report of 32 new cases with literature review

OBJECTIVE

To explore the clinical, imaging, pathologic characteristics and differential diagnosis of solitary pulmonary capillary hemangioma (SPCH).

METHODS

Thirty two cases of SPCH were collected and studied, with literature review.

RESULTS

This study included 13 males and 19 females, with a male-to-female ratio of 1:1.5. The age ranged from 26 to 70 years (median age of 43 years). All patients were asymptomatic at presentation. Lung nodules were incidentally discovered during chest computed tomography (CT). Imaging features included 21 cases with partial solid nodules (PSN), 7 cases with ground-glass nodules (GGN), and 4 cases with solid nodules (SN). Eleven cases were in the left lung lower basal segment, 11 cases in the right lung lower basal segment, 6 cases in the right lung upper anterior segment, and 4 cases in the right lung middle lateral segment. The lower basal segments of the lungs were involved in 22 (11 in each lung) cases (22/32, 68 %). The tumors ranged from 6 to 18 mm (average 10 mm). Macroscopically, 16 cases had clear boundaries, while 16 cases had unclear boundaries, and gray-red or dark brown on cut surfaces. Intraoperative frozen section was performed in 27 cases, with diagnosis of SPCH in 12 and pneumonia or inflammatory lesion in 15. Microscopically, the nodules were composed of densely proliferated and dilated capillaries. The capillary walls were lined with a single layer of flat endothelial cells, without atypical features. Collapsed alveolar septa were replaced by a large number of capillaries. All cases showed proliferating capillaries spreading into the walls of small veins/arteries and bronchi, with 3 cases showing dilated capillaries protruding into the bronchiolar lumens as polyp-like structures. Twenty-six cases (26/32, 81 %) showed proliferating capillaries passed over the interlobular septa. Twenty-six cases (26/32, 81 %) showed irregular intimal thickening of small muscular arteries in the peripheral areas of the lesions, with the thickened intima being cellular or fibrous. In twenty-seven cases (27/32, 84 %) the lesions were located in the subpleura, with 6 cases involving the pleura.

CONCLUSION

SPCH is a rare benign lung tumor that mostly occurs in the lung lower basal segments with predominance in females. It usually appears as a ground-glass nodule on CT and is very similar to early-stage lung cancer. Accurate diagnosis requires collaboration of radiologists, surgeons, and pathologists. SPCH should be regarded as an important differential diagnosis of small incidental lung nodules.

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.

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.

Hepatic hemangioma supplied by abnormal portal vein: A case report

Hepatic hemangioma is the most common hepatic tumor with a prevalence of approximately 3%. It is typically supplied by the hepatic artery as evident from findings of abdominal angiography, contrast-enhanced ultrasonography (CEUS), contrast-enhanced computed tomography (CT), and contrast-enhanced magnetic resonance imaging. However, few cases of hepatic hemangioma supplied by the portal vein have been reported. In this paper, we report a rare case of hepatic hemangioma supplied by the portal vein as shown on CEUS and CT arterioportography.

Prediction of pleural invasion using different imaging tools in non-small cell lung cancer

Clinical staging of non-small cell lung cancer (NSCLC) is used for planning therapeutic strategies. In particular, pleural invasion is regarded as an indicator for upstaging to T2 or T3 in the current 8th TNM staging system; patients with pleural invasion should be indicated for lobectomy rather than sublobar resection. Therefore, accurate preoperative prediction of pleural invasion is important for surgical planning. In recent years, different radiological investigations for patients with NSCLC have been widely used, and methods for more precise detection have been developed in the current medical imaging studies. Therefore, several radiological investigation tools have been used for the prediction of pleural invasion. In this article, to identify the imaging modalities for accurate prediction of pleural invasion, we reviewed the different methods used for this purpose and discussed their advantages and limitations.