Expression and significance of stem cell markers in pulmonary sclerosing haemangioma

Characteristics of metastatic and non-metastatic pulmonary sclerosing pneumocytomas

To characterize the clinicopathologic features of pulmonary sclerosing pneumocytoma (PSP) and compare these features between the tumors with and without metastasis, 68 cases of PSP (1/68 [1.47%] with metastasis) diagnosed from 2009-2022 in our hospital and 15 previously reported metastasizing cases were studied. There were 54 female patients and 14 male patients, with age ranging from 17 to 72 years and tumor size ranging from 0.1 to 5.5 cm (mean, 1.75 cm). In all, 85.4% of the cases presented with ≥2 patterns, including papillary, sclerotic, solid, and hemorrhagic. Thyroid transcription factor 1, epithelial membrane antigen, CKpan, and CK7 were expressed in surface cells in 100% of the cases and napsin A was expressed in 90% of the cases. Stromal cell expression of these markers occurred in 100%, 93.9%, 13.5%, 13.8%, and 0% of the cases, respectively. Of the 16 PSP cases with metastasis, 8 were female patients and 7 were male patients, with age ranging from 14 to 73 years. The tumor size ranged from 2.5 to 12 cm (mean, 4.85 cm). Forty-five of the cases were negative for BRAF V600E immunostaining and 6 were focally weak positive, in which fluorescent PCR tests showed no detectable mutations. There were significant differences in gender, age, and tumor size between PSP cases with and without metastasis. No BRAF V600E mutation was found in patients with PSP. AKT1 p.E17K mutations were detected in both the primary lung tumor and the lymph node metastatic tumor of our PSP case with lymph node metastasis. In conclusion, PSP is an uncommon pulmonary neoplasm with significant female predilection and has distinct morphologic and immunohistochemical characteristics. The BRAFV600E mutation was not detectable in patients with PSP and thus may not involve in its tumorigenesis. Most PSP tumors are benign, with a minority exhibiting potential for metastasis and malignant behavior.

Treatment and post-operative follow-up of pulmonary sclerosing pneumocytoma: A case report

Introduction and importance

Pulmonary sclerosing pneumocytoma (PSP) is a rare tumor thought to originate from respiratory epithelial cells. It is usually benign, but may rarely metastasize to lymph nodes. Surgeons face unique challenges in diagnosis and management of this condition, and ideal surgical management is yet to be established.

Case presentation

48-year-old woman with a 7 × 7 mm pulmonary lesion discovered incidentally on computerized tomography (CT) imaging, which grew to 9 mm over the following year. Seven years later, follow-up imaging revealed that the mass had grown to 1.3 cm in largest dimension. Surgery was recommended and the mass was resected via a right video-assisted thoracic surgery (VATS) middle lobectomy with mediastinal lymph node dissection. All lymph nodes were negative and the patient's postoperative course was unremarkable.

Clinical discussion

There are few evidence-based guidelines available on the treatment and postoperative surveillance of PSP. Research has shown comparable recurrence-free survival rates for sublobar resection and lobectomy, though recurrence can occur, especially following sublobar resection in larger or more centrally-located tumors. In absence of established guidelines, it was decided to follow this patient according to NCCN guidelines for surveillance of early-stage non-small cell lung cancer due to potential risk of recurrence.

Conclusion

This case report adds to the limited literature on PSP and depicts a possible treatment and postoperative follow-up plan. Right VATS middle lobectomy can effectively treat some cases of central PSP. In absence of established guidelines for postoperative follow-up of PSP, NCCN guidelines may outline one possible strategy for postoperative management.

Sclerosing pneumocytoma with carcinoid tumorlets and neuroendocrine cell hyperplasia

Sclerosing pneumocytoma is an uncommon pulmonary tumor which generally behaves benignly and occurs predominately in women. Rarely, it is associated with neuroendocrine proliferations such as hyperplasia, tumorlets and carcinoid tumors, which may be observed in relation to the tumor or in the distant lung parenchyma; the mechanism underlying this neuroendocrine differentiation is not clear. We present a case of a 33 year-old male with sclerosing pnemocytoma with coexistent neuroendocrine hyperplasia and combined carcinoid tumorlets. Taking into account the pluripotentiality of the round cells present in the sclerosing pneumocytoma, with positive staining for stem cells markers, it is possible that the different components of this neoplasia share a common origin, in accordance with previously reported findings.

Silencing long non-coding RNA MEG8 inhibits the proliferation and induces the ferroptosis of hemangioma endothelial cells by regulating miR-497-5p/NOTCH2 axis

Even though long non-coding RNA (lncRNA) MEG8 plays vital roles in carcinogenesis of malignances, its roles and mechanisms in hemangioma remain unknown. Therefore, we evaluate the oncogenic roles of MEG8 in hemangioma. Small interfering RNA (siRNA)-mediated depletion of MEG8 inhibited the proliferation and increased MDA level in human hemangioma endothelial cells (HemECs). The inhibitors of ferroptosis (ferrostatin-1 and liproxstatin-1) abolished the MEG8 silence induced cell viability loss. Knockdown of MEG8 increased the miR-497-5p expression and reduced the mRNA and protein levels of NOTCH2. Using a dual-luciferase assay, we confirmed the binding between MEG8 and miR-497-5p, and between the miR-497-5p and 3'UTR of NOTCH2. We further found that silencing MEG8 significantly decreased the expressions of SLC7A11 and GPX4 both in mRNA and protein level and had no effect on the level of AIFM2. Importantly, blocking miR-497-5p abrogated the effects of MEG8 loss on cell viability, MDA level and expression levels of NOTCH2, SLC7A11 and GPX4 in HemECs. Taken together, our results suggested that knockdown of long non-coding RNA MEG8 inhibited the proliferation and induced the ferroptosis of hemangioma endothelial cells by regulating miR-497-5p/NOTCH2 axis.

Clinical and histopathological features of pulmonary sclerosing pneumocytoma with dense spindle stromal cells and lymph node metastasis

AIMS

To determine the clinicopathological features of pulmonary sclerosing pneumocytoma (PSP) with spindle cells and in cases with positive detection of PSP cells in the lymph nodes.

METHODS AND RESULTS

This article report the clinical, histological and immunohistochemical features of PSP with dense spindle stromal cells in five patients (including one case with lymph node metastasis) and PSP accompanied by positive nodes in two patients out of 239 cases diagnosed at our institution between 2007 and 2019. The literature on PSP was also reviewed in detail. Six patients were female, and one (with a positive node) was male; their average age was 53 years. Thoracic imaging revealed solid tumours with clear borders and a uniform texture in six patients, but one patient had a lobulated tumour with uneven densities. All tumours were unifocal, and they had an average size of 31 mm. Tumours from five cases were mainly composed of solid regions of diffuse spindle cells rather than polygonal cells. Immunohistochemical staining demonstrated that thyroid transcription factor-1, vimentin, epithelial membrane antigen (weak) and oestrogen receptor (partial) were expressed in spindle cells. The average follow-up time was 31 months. Two of the 234 PSP cases for which adequate data were available had positive nodes (metastasis rate: 0.8%), and one of the five patients with PSP with spindle cells showed lymph node metastasis (metastasis rate: 20%). In addition, stromal cells were found to be predominant at metastatic sites.

CONCLUSIONS

Spindle cells are present among the stromal cells of PSP, and not all of them are round cells. PSP patients with spindle cells or male patients may be more prone to metastasis than others.

Symptomatic pulmonary sclerosing hemangioma: a rare case of a solitary pulmonary nodule in a woman of advanced age

Background

Pulmonary sclerosing hemangioma (PSH) is a rare tumor that usually develops in middle-aged Asian women. PSH has four histological types (hemorrhagic, sclerotic, solid, and papillary) and often grows slowly in a lower lobe of the lung. Preoperative misdiagnosis frequently occurs because of the absence of specific clinical manifestations and imaging findings. Few reports have described PSH in women of advanced age.

Case presentation: A 75-year-old woman presented to our hospital in China with a 5-day history of productive cough and intermittent hemoptysis. Computed tomography indicated bronchiectasis and a large mass in the left inferior lobe of the lung. Treatment of the bronchiectasis provided no symptom relief. The hemoptysis resolved following left lower pulmonary lobectomy, and PSH was pathologically diagnosed following surgery. At the time of this writing (after 6 months of follow-up), the tumor had not recurred, no metastases had been detected, and close follow-up was ongoing.

Conclusions

Both bronchiectasis and PSH can cause hemoptysis. This case demonstrates that PSH should be included as a differential diagnosis of hemoptysis in women of advanced age. For patients with chronic hemoptysis, the diagnosis of PSH should be considered if the therapeutic effect of bronchiectasis is poor.

Sclerosing pneumocytoma mixed with a typical carcinoid tumor: A case report and review of literature

RATIONALE

Sclerosing pneumocytoma accompanied with other type of tumor in one patient is very rare. Here, we report a case of a sclerosing pneumocytoma mixed with a typical carcinoid tumor in a same neoplasm.

PATIENT CONCERNS

A 55-year-old woman incidentally detected a space-occupying lesion of right lung in routine health examination. The patient was asymptomatic and there were no positive findings in routine laboratory examination, physical examination, and pulmonary function test. Computed tomography revealed a solitary round mass in the middle lobe of the right lung.

DIAGNOSIS

The lesion was diagnosed as a sclerosing pneumocytoma accompanied with a typical carcinoid tumor of the right lung.

INTERVENTION

The patient underwent thoracoscopic lobectomy in our hospital.

OUTCOMES

The postoperative course was uneventful.

LESSONS

This case is rare and noteworthy for a lesion containing two different types of neoplasms, which may cause diagnostic difficulties.

Sclerosing pneumocytoma with metastasis to the mediastinal and regional lymph nodes

Sclerosing pneumocytoma (SP) is an uncommon benign tumor, and metastasis of SP has been rarely reported. Here, we report the case of a 26-year-old woman with surgically confirmed SP. The tumor diameter was 40 mm, and metastasis to mediastinal and regional lymph nodes was observed. Immunohistochemically, both surface and round cells were positive for epithelial membrane antigen, thyroid transcription factor 1, and vimentin. Only surface cells expressed creatine kinase, carcinoembryonic antigen, napsin A, and cytokeratin 7, and only round cells expressed progesterone receptor. Ki-67 was detected in ~3% of cells, and the rate of weak positive p53 staining was 3%. Both cell types were negative for chromogranin A, synaptophysin, CD3, and CK20. Multiple metastases in a young SP patient are very rare, and potential mechanisms of metastasis may be related to epithelial-mesenchymal transformation.

A mixture of carcinoid tumors, extensive neuroendocrine proliferation, and multiple pulmonary sclerosing hemangiomas

We encountered an extremely rare case of multiple pulmonary sclerosing hemangiomas (PSH) with extensive neuroendocrine lesions, including pulmonary neuroendocrine cell (PNC) hyperplasia, multiple carcinoid tumorlets and typical carcinoid tumors within one pulmonary lobe. To the best of our knowledge, this is the first reported case in the English medical literature of PSH combined and admixed with carcinoid tumors and extensive neuroendocrine proliferation. This case is noteworthy for several reasons. First, the lesion is multi-nodular and unusually large for a typical PSH, which may mimic malignancy on imaging studies and cause diagnostic difficulties. Second, sampling bias may lead to diagnostic errors for a lesion containing two different types of neoplasms. Third, our case displays a rare mixed and mosaic pattern of PSH with a full spectrum of pulmonary neuroendocrine lesions, which may imply a potential intrinsic association in pathogenesis between PSH and concomitant neuroendocrine neoplasms. The clinical implication of multiple PSHs is also discussed.

Pulmonary sclerosing hemangioma presenting with dense spindle stroma cells: a potential diagnostic pitfall

Pulmonary sclerosing hemangioma (PSH) is an uncommon pulmonary tumor. Histologically, PSH typically consists of two types of cells, surface cuboidal cells and polygonal cells, four architectural patterns including papillary, sclerotic, solid, and hemorrhagic. Herein, we present a case of PSH in a 59-year-old Chinese female. The tumor was predominantly composed of solid area presenting with diffuse spindle cells rather than polygonal cells. Focally, classical papillary and sclerotic area could be seen. Immunohistochemical staining showed that the spindle cells were positive for TTF-1, EMA, Actin(SM) and Vimentin, and negative for cytokeratin, cytokeratin7, cytokeratin5/6, surfactant apoprotein A, surfactant apoprotein B, CD34, CD99, S-100, HMB45, Desmin, Synaptophysin, CD56, ALK and Calretinin. The immunophenotype of the dense spindle cells in this case was similar to that of the polygonal cells, and thus the spindle cells may be the variants of polygonal cells. Based on morphologic features and the immunohistochemical profile, the tumor was diagnosed as a PSH. The significance of spindle cells change is unclear for us. To our knowledge, this is the first reported case of PSH showing dense spindle cells in solid area. This case represents a potential diagnostic pitfall, as it may be misdiagnosed as a mesenchymal tumor such as inflammatory myofibroblastic tumor, synovial sarcoma, solitary fibrous tumor, leiomyoma, or even mesothelioma, especially if the specimen is limited or from fine- needle aspiration.