Pulmonary sclerosing pneumocytoma of the lung: CT characteristics in a large series of a tertiary referral center

Pulmonary sclerosing pneumocytoma mimicking a low-grade primary malignancy: A case report

INTRODUCTION

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign tumor classified as a pulmonary adenoma. It presents as a solitary pulmonary nodule without any specific findings, often posing a diagnostic challenge. We herein present a case of a PSP with a short volume doubling time (VDT) comparable to low-grade pulmonary malignancies.

CASE PRESENTATION

A 27-year-old female presented to the emergency department with a fever that had persisted for the past two days. An incidental finding on chest screening computed tomography (CT) revealed a 9 mm pulmonary nodule with a round shape and smooth margin, suggestive of a benign etiology. Follow-up CT one year later revealed an enlarged nodule exhibiting a VDT of 249 days. A thoracoscopic lingulectomy was performed, and the histopathological examination revealed papillary and diffuse proliferation of epithelial-like cells. The epithelial cells were positive for cytokeratin (CKAE1/AE3) and thyroid transcription factor 1 (TTF1), whereas the stromal cells were positive for TTF1 but negative for CKAE1/AE3. Those results were consistent with the diagnosis of a PSP.

DISCUSSION

PSPs typically present as incidental pulmonary nodules with no specific findings, often posing a diagnostic challenge. The radiographic features of PSPs have mainly been explored based on the morphological findings and metabolic activity, with limited research on their growth rate, represented by the VDT.

CONCLUSION

PSPs may exhibit rapid growth, demonstrating a short VDT similar to that of low-grade pulmonary malignancies. Comprehensive diagnostic testing not based solely on the growth rate for this rare condition is essential.

CT-based radiomics for differentiating peripherally located pulmonary sclerosing pneumocytoma from carcinoid

BACKGROUND

Pulmonary sclerosing pneumocytoma (PSP) and pulmonary carcinoid (PC) are difficult to distinguish based on conventional imaging examinations. In recent years, radiomics has been used to discriminate benign from malignant pulmonary lesions. However, the value of radiomics based on computed tomography (CT) images to differentiate PSP from PC has not been well explored.

PURPOSE

We aimed to investigate the feasibility of radiomics in the differentiation between PSP and PC.

METHODS

Fifty-three PSP and fifty-five PC were retrospectively enrolled and then were randomly divided into the training and test sets. Univariate and multivariable logistic analyses were carried to select clinical predictor related to differential diagnosis of PSP and PC. A total of 1316 radiomics features were extracted from the unenhanced CT (UECT) and contrast-enhanced CT (CECT) images, respectively. The minimum redundancy maximum relevance and the least absolute shrinkage and selection operator were used to select the most significant radiomics features to construct radiomics models. The clinical predictor and radiomics features were integrated to develop combined models. Two senior radiologists independently categorized each patient into PSP or PC group based on traditional CT method. The performances of clinical, radiomics, and combined models in differentiating PSP from PC were investigated by the receiver operating characteristic (ROC) curve. The diagnostic performance was also compared between the combined models and radiologists.

RESULTS

In regard to differentiating PSP from PC, the area under the curves (AUCs) of the clinical, radiomics, and combined models were 0.87, 0.96, and 0.99 in the training set UECT, and were 0.87, 0.97, and 0.98 in the training set CECT, respectively. The AUCs of the clinical, radiomics, and combined models were 0.84, 0.92, and 0.97 in the test set UECT, and were 0.84, 0.93, and 0.98 in the test set CECT, respectively. In regard to the differentiation between PSP and PC, the combined model was comparable to the radiomics model, but outperformed the clinical model and the two radiologists, whether in the test set UECT or CECT.

CONCLUSIONS

Radiomics approaches show promise in distinguishing between PSP and PC. Moreover, the integration of clinical predictor (gender) has the potential to enhance the diagnostic performance even further.

Cross-sectional imaging review of common to uncommon lung cancer mimickers in a tertiary care oncology center

Lung cancer is the most diagnosed cancer worldwide. Many non-malignant pulmonary lesions, such as tuberculosis, fungal infection, organizing pneumonia, inflammatory myofibroblastic tumor, and IgG4 disease, can mimic lung cancer due to their overlapping morphological appearance on imaging. These benign entities with minor differentiating imaging clues may go unnoticed in a high-volume cancer institution, leading to over-investigation that may result in repeated biopsies, pointless wedge resections, and related morbidities. However, with a thorough medical history, laboratory diagnostic work-up, and careful analysis of imaging findings, one can occasionally restrict the range of possible diagnoses or arrive at a definitive conclusion. When imaging features overlap, image-guided lung sampling is crucial since histopathological analysis is the gold standard.

Solitary pulmonary nodule in an early adolescent

An early adolescent boy presented with 1-week history of left-sided chest pain, localised to the anterior aspect of seventh intercostal space. A chest radiograph revealed a round opacity measuring 2.6×2.4 cm in the left mid zone. A CT scan of the chest confirmed a solitary well-circumscribed pulmonary nodule measuring 2.7×2.4 cm in the central left upper lobe, adjacent to the anterior segmental bronchus. Positron emission tomography scan showed mild to moderate fluorodeoxyglucose uptake (maximum standardized uptake value 5.2) in the nodule. He underwent a video-assisted left upper lobectomy. Histology of the nodule was consistent with sclerosing pneumocytoma, a rare benign lung neoplasm that occurs predominantly in middle-aged women of Asian descent. This case highlights the challenges in diagnosis and management of solitary pulmonary nodules in children, especially those who remain symptomatic or only have minimal symptoms and provides a pragmatic approach to this condition.

Central and peripheral pulmonary sclerosing pneumocytomas: multi-phase CT study and comparison with Ki-67

BACKGROUND

This study aimed to evaluate the multi-phase CT findings of central and peripheral pulmonary sclerosing pneumocytomas (PSPs) and compared them with Ki-67 to reveal their neoplastic nature.

PATIENTS AND METHODS

Multi-phase CT and clinical data of 33 PSPs (15 central PSPs and 18 peripheral PSPs) were retrospectively analyzed and compared their multi-phase CT features and Ki-67 levels.

RESULTS

For quantitative indicators, central PSPs were larger than peripheral PSPs (10.39 ± 3.25 cm3 vs. 4.65 ± 2.61 cm3, P = 0.013), and tumor size was negatively correlated with acceleration index (r = -0.845, P < 0.001). The peak enhancement of central PSPs appeared in the delayed phase, with a longer time to peak enhancement (TTP, 100.81 ± 19.01 s), lower acceleration index (0.63 ± 0.17), progressive enhancement, and higher Ki-67 level. The peak enhancement of peripheral PSPs appeared in the venous phase, with the shorter TTP (62.67 ± 20.96 s, P < 0.001), higher acceleration index (0.99 ± 0.25, P < 0.001), enhancement washout, and lower Ki-67 level. For qualitative indicators, the overlying vessel sign (86.67% vs. 44.44%, P = 0.027), prominent pulmonary artery sign (73.33% vs. 27.78%, P = 0.015), and obstructive inflammation/atelectasis (26.67% vs. 0%, P = 0.033) were more common in central PSPs, while peripheral PSPs were more common with halo sign (38.89% vs. 6.67%, P = 0.046).

CONCLUSIONS

The location of PSP is a possible contributing factor to its diverse imaging-pathological findings. The tumor size, multi-phase enhancement, qualitative signs, and Ki-67 were different between central and peripheral PSPs. Combined tumor size, multi-phase findings, and Ki-67 level are helpful to reveal the nature of the borderline tumor.

Magnetic resonance imaging findings of pulmonary sclerosing pneumocytoma: a case report and literature review

Background

Pulmonary sclerosing pneumocytoma (PSP) is a rare lung tumor that is mostly isolated and commonly reported among middle-aged East Asian women. Recently, Immunohistochemistry (IHC) analysis has suggested that PSP is of primitive epithelial origin, most likely derived from type II alveolar air cells. Patients with PSP are generally asymptomatic and usually detected for other unrelated reasons during routine imaging. Several studies have already investigated the computed tomography (CT) features of PSP and their correlation with pathology. Magnetic resonance imaging (MRI) is a radiation-free imaging technique with important diagnostic value for specific pulmonary nodules. However, very few case reports or studies focus on the MRI findings of PSP.

Case report

We reported a case of an asymptomatic 56-year-old female with a solitary, well-defined soft-tissue mass in the lower lobe of the left lung. The mass showed iso-to-high signal intensity (SI) than muscle on T1-weighted image (T1WI) and T2-weighted image (T2WI) and a much higher SI on fat-suppressed T2WI, diffusion-weighted image, and apparent diffusion coefficient image. Contrast-enhanced fat-suppressed T1WI revealed noticeable inhomogeneous progressive enhancement throughout the mass. The mass revealed early enhancement without a significant peak, followed by a plateau pattern on dynamic contrast-enhanced MRI images. The patient underwent left basal segmentectomy via thoracoscopic surgery. Histopathology and IHC results of the surgical specimen confirmed that it was a PSP. We concluded that the MRI findings of PSP might adequately reflect the different components within the tumor and aid clinicians in preoperative diagnosis and assessment. To the best of our knowledge, this is the most comprehensive case report on the MRI findings of PSP.

Conclusion

The MRI findings of PSP correspond to its histopathological features. Here, we present a case of PSP with the most comprehensive MRI findings, emphasizing the importance of multiple-sequence MRI in diagnosing PSP.

Giant pulmonary sclerosing pneumocytoma with potentially malignant biological behavior: a case report and literature review

Background

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign lung tumor which generally presents as a solitary pulmonary nodule in middle-aged females. However, the PSP in some patients exhibits potentially malignant biological behavior, with recurrence and lymphatic or distant metastasis being observed.

Case Description

We encountered a case of a 46-year-old female with an inordinately massive tumor 9.5 cm in diameter and a relatively high Ki-67 proliferation rate. Fine needle aspiration (FNA) played a significant but limited role in the preoperative diagnosis: the computed tomography (CT)-guided lung puncture biopsy was consistent with the typical pathology of PSP; however, endobronchial ultrasound-guided transbronchial lung biopsy (EBUS-TBLB) could not provide a definitive diagnosis. The patient ultimately underwent thoracoscopic resection and mediastinal lymph node dissection. Here, we provide a review of the literature on patients with PSP with malignant biological behavior to raise awareness of the malignant potential of PSP and describe our experience to inform future management.

Conclusions

PSP lacks specificity in its clinical and radiological characteristics and has complex pathological manifestations. FNA is valuable in the diagnosis and differential diagnosis of PSP but involves the risk of misdiagnosis or missed diagnosis. Additionally, we believe that the accepted benign features of PSP need to be updated and that the potential malignant features of PSP should be carefully monitored. Surgical resection is curative but strict follow-up is crucial.

Pulmonary sclerosing pneumocytoma and mortality risk

Background

Surgical resection is usually recommended for the treatment of pulmonary sclerosing pneumocytoma (PSP). However, no comparative study has demonstrated that surgical resection leads to improved outcomes. We aimed to compare all-cause mortality between patients with PSP who underwent surgery or did not and those without PSP.

Methods

Participants aged ≥18 years who had pathologically diagnosed PSP between 2001 to 2018, at 3 hospitals were included. Randomly selected (up to 1:5) age-, sex-, and smoking status-matched controls without PSP who were randomly selected from those who underwent health checkups including chest CT were included. Mortality was compared using Kaplan–Meier estimates and Cox proportional hazards regression models. Literature review of studies reporting PSP was also conducted.

Results

This study included 107 patients with PSP (surgery:non-surgery, 80:27) and 520 matched controls. There were no cases of lymph node or distant metastasis, recurrence, or mortality from PSP. No significant difference in all-cause mortality risk was observed between the PSP surgery, PSP non-surgery, and non-PSP groups (log rank test P = 0.78) (PSP surgery vs. non-PSP: adjusted hazards ratio [aHR], 1.80; 95% confidence interval [CI], 0.22–14.6; PSP non-surgery vs. non-PSP: aHR, 0.77; 95% CI, 0.15–3.86; PSP surgery vs. PSP non-surgery: aHR, 2.35; 95% CI, 0.20–28.2). In the literature review, we identified 3469 patients with PSP from 355 studies. Only 1.33% of these patients reported metastasis, recurrence, or death.

Conclusions

All-cause mortality did not differ between patients with PSP and those without, irrespective of undergoing surgery. Our study and the literature review suggest that PSP has less impact on increased mortality risk.

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 Pulmonary Sarcoidosis: A Case Report

Pulmonary sclerosing pneumocytoma, formally named pulmonary sclerosing hemangioma, is a rare benign tumor with malignant potential often identified as solid pulmonary nodules. Sarcoidosis is an inflammatory, multisystemic disease of unknown cause with a wide range of clinical manifestations. The disorder is characterized by the formation of noncaseating granulomas in virtually any organ in the body. We present a case of a patient presenting with fever, weight loss, and respiratory symptoms found to have both a sclerosing pneumocytoma and pulmonary sarcoidosis. A diagnosis was made following the lobectomy. The patient was followed for two years with stable lymphadenopathy while remaining asymptomatic.

VATS approach for pulmonary sclerosing pneumocytoma: a case report

INTRODUCTION

Pulmonary Sclerosing Pneumocytoma (PSP) is a rare type of benign lung tumor usually encountered in middle-aged Asian women. The lesion is mostly found on routine chest x-rays. Though surgery is recognized as the recommended treatment, there is no consensus on the standard operative procedure for this tumor.

CASE PRESENTATION

We report a case of a 48 year-old Caucasian woman who presented with a right para-hilar mass mimicking a hydatid cyst. After an unsuccessful initial treatment with oral Albendazole, and a steady growth over 10 years, the patient was programmed for surgical resection by video-thoracoscopic (VATS) approach. We were able to completely resect the tumor by VATS. Histopathological analysis suggested the diagnosis of Pulmonary Sclerosing Pneumocytoma. No further treatment was required and the patient was rapidly discharged.

CONCLUSIONS

Pulmonary sclerosing pneumocytoma is a rare form of benign tumor that should be part of the differential diagnosis of lung lesions of unknown origin. Because of its well-defined encapsulated structure allowing total enucleation, VATS can be proposed as a less invasive alternative to classic thoracotomy.

Pulmonary sclerosing pneumocytoma-a case series

Pulmonary sclerosing pneumocytoma (PSP) is a rare and interesting pulmonary tumour that presents a diagnostic challenge to the surgeon due to its bland symptomatology, indolent course, non-specific radiological features and ambiguous histopathological findings, which could lead to errors in management and prognostication. Herein, we present a series of 4 patients with PSP who were managed in our institution over a period of 8 years and briefly discuss relevant literature.

Analysis of the value of enhanced CT combined with texture analysis in the differential diagnosis of pulmonary sclerosing pneumocytoma and atypical peripheral lung cancer: a feasibility study

BACKGROUND

As a rare benign lung tumour, pulmonary sclerosing pneumocytoma (PSP) is often misdiagnosed as atypical peripheral lung cancer (APLC) on routine imaging examinations. This study explored the value of enhanced CT combined with texture analysis to differentiate between PSP and APLC.

METHODS

Forty-eight patients with PSP and fifty patients with APLC were retrospectively enrolled. The CT image features of the two groups of lesions were analysed, and MaZda software was used to evaluate the texture of CT venous phase thin-layer images. Independent sample t-test, Mann-Whitney U tests or χ² tests were used to compare between groups. The intra-class correlation coefficient (ICC) was used to analyse the consistency of the selected texture parameters. Spearman correlation analysis was used to evaluate the differences in texture parameters between the two groups. Based on the statistically significant CT image features and CT texture parameters, the independent influencing factors between PSP and APLC were analysed by multivariate logistic regression. Extremely randomized trees (ERT) was used as the classifier to build models, and the models were evaluated by the five-fold cross-validation method.

RESULTS

Logistic regression analysis based on CT image features showed that calcification and arterial phase CT values were independent factors for distinguishing PSP from APLC. The results of logistic regression analysis based on CT texture parameters showed that WavEnHL_s-1 and Perc.01% were independent influencing factors to distinguish the two. Compared with the single-factor model (models A and B), the classification accuracy of the model based on image features combined with texture parameters was 0.84 ± 0.04, the AUC was 0.84 ± 0.03, and the sensitivity and specificity were 0.82 ± 0.13 and 0.87 ± 0.12, respectively.

CONCLUSION

Enhanced CT combined with texture analysis showed good diagnostic value for distinguishing PSP and APLC, which may contribute to clinical decision-making and prognosis evaluation.

Pulmonary Sclerosing Pneumocytoma: An Essential Differential Diagnosis for a Lung Nodule

Pulmonary sclerosing pneumocytoma, previously known as pulmonary sclerosing hemangioma, is a rare benign lung tumor with a low prevalence. We present this condition in a 26-year-old, young, non-smoking female with a slow-growing pulmonary nodule incidentally noted on imaging. Serial computed tomography(CT) scans revealed slow growth, and invasive testing was recommended. The patient underwent a left lateral thoracotomy and based on frozen section findings. A left lower lobectomy was performed. The final pathological diagnosis revealed sclerosing pneumocytoma. This is an atypical patient demographic considering the propensity of the disease for middle-aged Asian women. The case presentation and work-up highlight this critical differential diagnosis for incidental pulmonary nodules increasingly being noted due to widespread use of imaging for screening and routine care in the current medical climate. There are no specific imaging criteria to diagnose this condition. The final diagnosis is made only after surgical biopsy and histopathology. No additional treatment is needed following the diagnosis.

Pulmonary sclerosing pneumocytoma mimicking carcinoid on preoperative imaging in a 14-year-old female

Pulmonary sclerosing pneumocytoma is a rare benign neoplasm of the lung, commonly occurs in middle-aged persons with a marked female predominance. Earlier, it was known as sclerosing hemangioma. Here, we present a case of pulmonary sclerosing pneumocytoma which was diagnosed as carcinoid of the lung, based on imaging, in a 14-year-old female. Besides radiology, the uniqueness of this case lies in the young age (14 years) of the patient. She was presented with a 3.3 × 2.5 × 2.2 cm soft tissue density mass with a tiny speck of calcification in the anterior basal segment of the lower lobe of the right lung. Based on imaging findings on fluorodeoxyglucose positron emission tomography (FDG PET) scan and DOTANOC scan, a diagnosis of carcinoid was made. We performed a video-assisted thoracoscopic right lower lobectomy. Histopathological examination showed features of pulmonary sclerosing pneumocytoma. Surgery is an established method of treatment for pulmonary sclerosing pneumocytoma. Enucleation, lobectomy, sleeve resection are possible treatment options. To define the role of adjuvant therapy, further direct evidence is required. The metastatic potential of this disease is yet to be established.

Case Report and Literature Review: Pulmonary Sclerosing Pneumocytoma With Multiple Metastases Harboring AKT1 E17K Somatic Mutation and TP53 C176Y Germline Mutation

Pulmonary Sclerosing Pneumocytoma (PSP) is considered as a benign tumor, although a few cases have been reported to have multiple lesions, recurrence, and even regional lymph nodes (LNs) metastasis. Here, we report a case of PSP with atypical histologic features and malignant biological behavior, and explore its molecular genetic changes. The 23-year-old male showed a 6.5-cm pulmonary nodule in the right middle lobe (RML) and enlarged media stinal LNs. He underwent thoracoscopic RML lobectomy, systematic LNs dissection, and mediastinal lymphadenectomy. The metastases to the cervical LNs and liver were detected in a short period and then resected. Postoperative pathological examination confirmed the diagnosis of PSP in all the lesions, based on the histological characteristics and immune phenotypes. Furthermore, whole-exome sequencing identified both AKT1 E17K somatic mutation and TP53 C176Y germline mutation in this case. Thus, we presented an extremely rare case of atypical PSP with rapid recurrence and multiply metastases, which can easily be misdiagnosed as primary lung cancer. In addition, PSP-specific AKT1 E17K somatic E17K somatic mutation accompanied with TP53 C176Y germline mutation may contribute to the malignant clinical course of this tumor.

A case of pulmonary sclerosing pneumocytoma diagnosed preoperatively using transbronchial cryobiopsy

Background

The preoperative diagnosis of pulmonary sclerosing pneumocytoma (PSP) is complicated since PSP has several histological structural patterns in the same neoplasm; hence, it is sometimes pathologically misdiagnosed as adenocarcinoma or carcinoid. In recent years, with the prevalence of transbronchial cryobiopsy (TBLC), we are able to obtain larger specimens than previously. However, to date, there have been no reports describing PSP diagnosed using TBLC.

Case reports

A 43-year-old man was referred to our hospital for an abnormal lesion in the left lung discovered on routine health examination. A computed tomography scan of the chest revealed a 14-mm heterogeneous round nodule with surrounding ground-glass opacity in the left lower lobe. The tumor size increased to 18 mm in three weeks, and he developed bloody sputum. TBLC was performed using radial endobronchial ultrasonography and fluoroscopy. An occlusion balloon and prophylactic epinephrine were used to prevent severe bleeding. Histologically, epithelioid cells with solid proliferation, various papillary lesions, and hemosiderin-laden histiocytes were observed. Immunohistochemical staining revealed the histiocytes positive for thyroid transcription factor-1 and vimentin, and the type II pneumocyte-like-cells positive for cytokeratin 7. The tumor was preoperatively diagnosed as a PSP; the patient underwent left basal segmentectomy and consequently, a final diagnosed of PSP was formulated.

Conclusion

We report the first case of PSP preoperatively diagnosed using TBLC. Therefore, cryobiopsy could be beneficial in the preoperative diagnosis of PSP.

Pulmonary Adenofibroma: Clinicopathological and Genetic Analysis of 7 Cases With Literature Review

Introduction

Pulmonary adenofibroma (PAF), characterized by biphasic differentiation composed of gland-like space lined by respiratory epithelium and stromal spindle cells, is a rare benign tumor of the lung. PAF was reported infrequently and inconsistently with diagnostic criteria and withstood higher risk of misdiagnosis as solitary fibrous tumors (SFTs) due to their morphological resemblance. In this study, we report seven cases of PAF with gene sequencing results and summarize the data of previous literature.

Materials and Methods

Seven cases of PAF with surgically resection samples were collected from Pathology department of West China Hospital, Sichuan University between 2009 to 2020. Immunohistochemical studies were performed in all cases and 3 cases underwent a 425-gene panel next-generation sequencing (NGS).

Results

Five female and two male patients were included in this study, with an average age of 51 years. All the patients were asymptomatic, and the lesion was identified on routine chest radiography. The tumor size measured by computed tomography (CT) ranged from 0.5 to 2.7 cm. Gland-like structures were mostly positive for glandular epithelium markers. The spindle cells in stroma expressed Desmin, SMA, ER and PR in 3 of 7 cases. No well-recognized molecular abnormalities can be identified by NGS in the 3 cases. To date, all the patients are alive, with no evidence of recurrence and metastasis.

Conclusion

PAF is a unique benign pulmonary tumor with low incidence. Biphasic morphology, IHC stains along with molecular detection is of great significance to make a clear diagnosis.

Analysis of the F-18 FDG PET/CT features of pulmonary sclerosing pneumocytoma

PURPOSE

This retrospective study aimed to analyzed the F-18 fluorodeoxyglucose PET/computed tomography (F-18 FDG PET/CT) features of pulmonary sclerosing pneumocytoma (PSP) to improve the understanding and preoperative diagnostic efficacy of this rare disorder.

METHODS

FDG PET/CT images from 11 patients with 22 lesions (including one patient with 12 lesions) proven PSP in our hospital were reviewed. We summarized the PET/CT features of PSP and analyzed the correlation between FDG uptake and tumor size.

RESULTS

PET/CT imaging revealed all tumors located in each lobe of the two lungs randomly. All 22 tumors were round or oval nodules; 15 had smooth margins, six were lobulated, six were calcified, and one had a ground-glass halo sign. The mean diameter of these tumors was 19.2 ± 7.8 mm (range: 8-34 mm); the mean maximum standardized uptake value (SUVmax) was 2.8 ± 1.3 (range: 1.1-7.4). Sixteen of the lesions exhibited mild to moderate FDG uptake (mean SUVmax 2.3 ± 0.6), and six of the lesions exhibited intense FDG uptake (mean SUVmax 4.3 ± 1.6). A positive correlation was observed between FDG uptake and tumor size (P <0.05).

CONCLUSION

Single round or ovoid soft-tissue lesions with smooth margins, and mild to moderate FDG uptake on PET/CT images in middle-aged females, suggest a possible diagnosis of PSP. For some atypical cases with intense FDG uptake, a diagnosis of PSP also can be considered. A statistically significant positive correlation was found between SUVmax and PSP lesion size in our study.

Pulmonary Sclerosing Pneumocytoma: A Pre and Intraoperative Diagnostic Challenge. Report of Two Cases and Review of the Literature

Pulmonary sclerosing pneumocytoma is a rare benign pulmonary tumor of primitive epithelial origin. Because of the unspecific radiological features mimicking malignancies and its histological heterogeneity, the differential diagnosis with adenocarcinoma and carcinoid tumors is still challenging. We report our experience of two cases of sclerosing pneumocytoma, as well as a review of the literature. Immunohistochemical findings showed intense staining of the cuboidal epithelial cells for cytokeratin-pool and TTF-1, with focal positivity for progesterone receptors. Round and spindle cells expressed positivity for vimentin, TTF-1 and focally for the progesterone receptor. Cytologic diagnosis of pulmonary pneumocytoma requires the identification of its dual cell population, made up of abundant stromal cells and fewer surface cells. Since the pre- and intraoperative diagnosis should guide surgical decision making, obtaining a sufficient specimen size to find representative material in the cell block is of paramount importance.

Large pulmonary sclerosing pneumocytoma in a young female: A rare lung tumor

We report a case of a 28‐year‐old female who presented with a solid mass lesion in the right middle lobe (RML). A chest computed tomography (CT) scan showed a 3.5 cm sized round and solid mass between the medial and lateral segment of the RML. The patient underwent a percutaneous lung biopsy with CT scan guidance and pathological examination showed pulmonary sclerosing pneumocytoma. RML lobectomy was performed for definitive treatment. Here, we describe this rare lung disease which presented as a large homogeneous lesion. Pulmonary sclerosing pneumocytoma should be considered in the differential diagnosis of solitary lung tumor, even if the patient is young.

Rare pulmonary tumors and carcinoma mimickers; experience from an interventional radiology unit with radiologic-pathologic correlation-A pictoral essay

BACKGROUND

Although imaging findings along with patients' clinical history may give clue for the etiology of a pulmonary lesion, the differentiation of benign pulmonary lesions from lung cancer could be challenging.

OBJECTIVE

The aim of this review article was to increase the awareness of the carcinoma mimicking lung lesions.

METHODS

This paper was designed to illustrate rare pulmonary tumors and carcinoma mimickers with emphasis on radiologic-pathologic correlation. Pitfalls encountered on CT images and also false positivity of PET-CT scans were also presented.

CONCLUSION

Several benign pulmonary lesions may grow in size on follow-up and some may show pathologic FDG (18F-fluorodeoxyglucose) uptake, which makes them indistinguishable from lung carcinoma by imaging. In addition, some slow-growing malignant lesions, such as carcinoid, may be false-negative on PET/CT scans.

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.

Correlation Between Pulmonary Sclerosing Pneumocytoma Features and MSCT Imaging Manifestations in 34 Patients: Implications for Precision Medicine

Objective: To identify and analyze the multi-slice computed tomography (MSCT) imaging manifestations and clinicopathological features of PSP to improve the preoperative and intraoperative diagnosis of the disease. Method: This was a retrospective study conducted on the imaging and clinicopathological data of the PSP patients treated in two major hospitals in China from October 2001 to December 2019. The locations of lung lesions, clinical symptoms, surgical complications, MSCT imaging features, and the corresponding relationship with clinicopathological features were assessed. Then, a new diagnostic approach was defined and used to train imaging and pathological doctors (experimental group). Then, the diagnostic accuracy of the experimental group was evaluated in preoperative and intraoperative diagnosis of PSP. Results: Thirty-four PSP cases were analyzed (mean: 51.42; range: 39-69 years old). The peripheral type was more common, while 92% of the lesions located in the middle lobe of the right lung and the lower lobe of bilateral lungs. The shortest lesion edge-pleura distance ranged 0 to 30 mm and 46% of the lesions (16/34) were attached to the pleura, 62% (21/34) located at 0-5 mm, 92% (31/34) within 20 mm from the pleura. Diameters of the lesions ranged 8.58 to 68.41 mm, while most of them were 20-40 mm. All lesions showed enhancement, and 97% (33/34) were unevenly enhanced. PSP volume was negatively correlated with the total degree of enhancement (r = -0.587, p < 0.01), and the volume difference between the obvious enhancement zone and the slight enhancement zone (r = -0.795, p < 0.01). Welt vessel sign was observed in 61.7% (21/34) of cases, and none of welt vessels entered into the lesions. Vascular-like enhancement area inside the lesion showed no significant correlation with the welt vessels outside the lesion, and no case showed entrance of bronchus into the lesion. The trained experimental group showed significantly greater diagnostic accuracy than the control group. In particular, the accuracy rate of intraoperative frozen section diagnosis was 60% higher in the experimental group than the control group. Conclusion: PSP has characteristic imaging manifestations, which can be utilized to improve the preoperative and intraoperative diagnostic coincidence rate of PSP.

68Ga-DOTATATE-avid pulmonary sclerosing pneumocytoma in a man of North African descent: Case report, imaging findings and pathology

Pulmonary sclerosing pneumocytoma (PSP) is a benign tumor originating from primitive respiratory epithelium which tends to present as an asymptomatic solitary lesion in the periphery of the lung. It primarily occurs in women, with a 5:1 ratio of female to male, and in East Asian populations. We describe a rare case of a gallium-68 (⁶⁸Ga)-DOTATATE avid PSP in a middle-aged man of North African ancestry. Contrast-enhanced computed tomography (CT) revealed an enhancing ovoid 2-cm solid lesion within the periphery of the left upper lobe abutting the superior portion of the lateral left ventricular wall. A fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) demonstrated low-level FDG uptake, but a ⁶⁸Ga-DOTATATE PET/CT showed avid tracer uptake, concerning for a carcinoid tumor. The lesion was surgically excised, and the histopathologic analysis revealed the typical morphologic and histochemical markers of a PSP. We conclude that, although rare, PSP can be a differential consideration when evaluating a ⁶⁸Ga-DOTATATE-avid solitary lung nodule concerning for carcinoid tumor, in all genders and in ethnicities other than East Asian.

Sclerosing pneumocytoma in a 1-year-old girl presenting with massive hemoptysis: A case report

Introduction and importance

Sclerosing pneumocytoma (SP) is a rare benign neoplasm of the lung with peak age incidence in middle aged-women. Here we report, for the first time in the literature, a case of a 1-year-old girl with SP.

Case presentation

A 1-year-old girl was reported to emergency department for massive hemoptysis. After admission, the patient had a three-days episode of melena, with normal body temperature and generally stable condition.

Clinical discussion

Fiberoptic bronchoscopy was normal. MSCT was done along with angiography and Three-Dimensional Reconstruction which revealed a well-circumscribed round mass with well-defined borders located near the vessels in the upper lobe of left lung. Anatomic lingula resection was performed. Hilar node was also resected. The histopathological examination confirmed the presence of SP. Fourteen months postoperatively, the patient was in a good health with no clinical or radiological evidence of recurrence.

Conclusion

SP is a rare benign tumor which usually presents in middle aged-women asymptomatically or with nonspecific symptoms. We report this case to highlight that SP should be considered in cases of hemoptysis in young children.

Differentiation of pulmonary sclerosing pneumocytoma from solid malignant pulmonary nodules by radiomic analysis on multiphasic CT

Purpose

To investigate the diagnostic value and feasibility of radiomics‐based texture analysis in differentiating pulmonary sclerosing pneumocytoma (PSP) from solid malignant pulmonary nodules (SMPN) on single‐ and three‐phase computed tomography (CT) images.

Materials and Methods

A total of 25 PSP patients and 35 SMPN patients with pathologically confirmed results were retrospectively included in this study. For each patient, the tumor regions were manually labeled in images acquired at the noncontrast phase (NCP), arterial phase (AP), and venous phase (VP). The least absolute shrinkage and selection operator (LASSO) method was used to select the most useful predictive features extracted from the CT images. The predictive models that discriminate PSP from SMPN based on single‐phase CT images (NCP, AP, and VP) or three‐phase CT images (Combined model) were developed and validated through fivefold cross‐validation using a logistic regression classifier. Model performance was evaluated using receiver operating characteristic (ROC) analysis. The predictive performance was also compared between the Combined model and human readers.

Results

Four, five, and five features were selected from NCP, AP, and VP CT images for the development of radiomic models, respectively. The NCP, AP, and VP models exhibited areas under the curve (AUCs) of 0.748 (95% confidence interval [CI], 0.620–0.852), 0.749 (95% CI, 0.620–0.852), and 0.790 (95% CI, 0.665–0.884) in the validation dataset, respectively. The Combined model based on three‐phase CT images outperformed the NCP, AP, and VP models (all p < 0.05), yielding an AUC of 0.882 (95% CI, 0.773–0.951) in the validation dataset. The Combined model displayed noninferior performance compared to two senior radiologists; however, it outperformed two junior radiologists (p = 0.004 and 0.001, respectively).

Conclusion

The Combined model based on radiomic features extracted from three‐phase CT images achieved radiologist‐level performance and could be used as promising noninvasive tool to differentiate PSP from SMPN.

Sclerosing pneumocytoma mixed with a columnar clear cell adenoma and a typical carcinoid: case report and review of literature

Sclerosing pneumocytoma (SP) is a rare and benign tumor predominantly occurring in Asian women, easily misdiagnosed by imaging and pathologic frozen diagnosis during surgery because of its diverse histomorphology (4 structures, 2 types of cells). It may form multiple tumors. When SP is combined with carcinoid, adenoma, or other tumors (although rare), diagnosis is more complicated. SP mixed with carcinoid tumor is rare. At present, only 4 cases have been reported in English literature. Here, we report a case of sclerosing pneumocytoma combined not only with carcinoid, but also with clear cell adenoma of the lung. The patient was a 52-year-old female and CT found a nodule in the middle lobe of the right lung. SP was not excluded by intraoperative frozen section diagnosis. The above 3 components formed a 1.4 cm nodule. The related literature is reviewed to strengthen the understanding of SP, and aid clinicopathological diagnosis.

Expression of ALDH and SOX-2 in Pulmonary Sclerosing Pnemocytoma (PSP) of the Lung: Is There a Meaning Behind?

Background: Pulmonary sclerosing pneumocytoma (PSP) is a rare benign pulmonary tumor that derives from primitive respiratory epithelium of the pulmonary alveolus. The etiology and pathogenesis are still unclear. Histopathological diagnosis focuses on cells that are positive for TTF1, EMA, cytokeratin-7, and CAM 5.2. The aim of our study is to highlight the elevated expression of ALDH and the presence of SOX-2 in pulmonary sclerosing pneumocytoma.

Methods: We report five cases of pulmonary sclerosing pneumocytoma undergone surgery at our Division of Thoracic Surgery, during a period between 1994 and 2011. ALDH and SOX-2 markers were also tested for positivity in all the patients.

Results: Patients showed elevated expression of ALDH during immunohistochemistry and mild expression of SOX-2, although in two cases in which SOX-2 was highly expressed. Among these two patients, one presented with lymph node recurrence while the other had no recurrence with a PET-positive nodule. In particular, the patient who had developed recurrence had an ALDH score of 4 and a SOX-2 score of 3, whereas the patient with the PET-positive nodule showed an ALDH score of 4 with a mild SOX-2 expression of score 1.

Conclusions: This is the first attempt demonstrating the elevated expression of ALDH in this disease. SOX-2 expression was noted in both the patient who developed recurrence and the patient with a PET-positive nodule. We believe that further investigation may be highly useful to better characterize these two markers as well as understand their function.

Pulmonary sclerosing pneumocytoma with mediastinal lymph node metastasis: a case report

Pulmonary sclerosing pneumocytoma (PSP) is a rare tumor and the imaging appearance is usually a well-circumscribed nodule. Herein we present the clinicopathological features of a 25-year-old female patient with a 4 cm mass in the left upper lobe. She had undergone lobectomy with lymph node dissection with an incorrect intraoperative frozen section diagnosis of adenocarcinoma and diagnosed as a PSP with lymph node metastasis on permanent sections. The 3-year follow-up of the patient is uneventful.

Pulmonary sclerosing pneumocytoma in an 18-year-old male patient: A case report and literature review

RATIONALE

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign tumor of the lung, mostly presented in Asian middle-aged women. Initially, it was considered as a vascular origin tumor, but then research evidence showed that it was derived from natural epithelial tissue. On imaging, this tumor may be found as a solitary well-circumscribed lung parenchymal lesion, and is often located in juxtapleural or juxtafissural positions. On histopathology, it consists of cuboidal surface cells and stromal round cells, both of which are positive for thyroid transcription factor-1. Here we report a case of a young PSP male patient and review the relevant literature in order to improve our understanding of this disease.

PATIENT CONCERNS

An 18-year-old man was referred to our hospital after accidentally finding a lesion on chest X-ray. Contrast-enhanced computed tomography showed a soft tissue mass with homogeneous enhancement in the left lower lobe posterior segment.

DIAGNOSES

The diagnosis of PSPs was confirmed by histopathological examination.

INTERVENTIONS AND OUTCOMES

The patient underwent a thoracoscopic wedge resection and was followed-up after that. One month later, he had good performance status with no recurrent tumors.

LESSONS

PSP in a young man is really uncommon, and is confused with malignant tumors. A histopathological examination is considered as the diagnostic gold standard for this uncommon tumor. Surgery is the main treatment.

Pulmonary sclerosing pneumocytoma: Cytomorphology and immunoprofile

BACKGROUND

Sclerosing pneumocytoma (SP) is a rare, benign pulmonary neoplasm. To the authors' knowledge, the current study is the first to evaluate the cytomorphology and immunoprofile of SP in a series.

METHODS

A total of 9 fine-needle aspiration cases of SP (7 of which were computed tomography guided and 2 of which were endobronchial ultrasound guided) including histopathology and immunohistochemistry were collected from 5 institutions.

RESULTS

The female-to-male ratio was 3.5:1, and the mean age of the patients was 54 years (range, 27-73 years). All cases presented as lung nodules, with a mean size of 2.2 cm (range, 1.1-5 cm), and were interpreted as atypical on rapid on-site evaluation. The final diagnoses were favor adenocarcinoma (1 case), well-differentiated lung adenocarcinoma (2 cases), low-grade epithelial neoplasm (2 cases), and sclerosing pneumocytoma (4 cases). Samples were moderately cellular, and consisted of round epithelioid cells with clear cell features, columnar cells, and spindle cells. A papillary arrangement with prominent hyalinized fibrovascular cores was the most common architectural pattern, followed by flat sheets and acinar formations. Tumor cells demonstrated mild, focally moderate nuclear pleomorphism with prominent nucleoli, hyperchromasia, nuclear elongation, nuclear overlap, and occasional nuclear inclusions and grooves. The background consisted of foamy macrophages (9 cases), hemosiderin pigment (6 cases), and lymphoid aggregates (3 cases) with no mitoses and/or necrosis. The surface cells and underlying round cells were positive for both thyroid transcription factor 1 and epithelial membrane antigen in all cases, which was the most notable immunohistochemical finding.

CONCLUSIONS

Cytomorphological findings of SP overlap with those of well-differentiated lung adenocarcinoma. Awareness of these cytomorphologic findings and the distinct immunoprofile of the 2 cell types found in SP should prevent a misdiagnosis and aggressive treatment.

Sclerosing Pneumocytoma of the Lungs Arising in a Child With PTEN Mutation

We report a rare case of sclerosing pneumocytoma occurring in a child with PTEN mutation. A 13-year-old female presented to the emergency department of an adult hospital following 2 to 3 days of upper respiratory tract infection symptoms. A primary lung lesion was discovered during her initial chest X-ray to rule out pneumonia. The patient underwent an uneventful thoracoscopic right upper lobe segmentectomy. The pathology demonstrated a sclerosing pneumocytoma of the lung. She tested positive for PTEN hamartoma tumor syndrome with a pathogenic variant at c.388 C > T. The PTEN mutation was also identified in the sclerosing pneumocytoma. Further study of PTEN mutation in sclerosing pneumocytoma is warranted.

Pulmonary sclerosing pneumocytoma demonstrating intratumoral hematoma

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign neoplasm of the lung that shows a slow growing pattern. Corresponding contrast-enhancements on chest computed tomography (CT) vary widely in both patterns and degrees. However, gross intratumoral radiolucencies, attributable to cyst formation, necrosis, or intratumoral hematoma, were rarely reported in PSP cases. We herein report on a case involving a 61-year-old Japanese women with PSP demonstrating CT-defined intratumoral radiolucency. A chest CT scan revealed a solitary and well-circumscribed nodule that showed a substantial growth over a 7-year period. The tumor was composed of a solid portion visualized with contrast-enhancement and a central radiolucency on a chest CT scan. A positron emission tomography scan revealed high uptake of fluorodeoxyglucose on the solid portion of the tumor, but the radiolucent portion showed negative uptake. The examination of a tumor specimen obtained by a percutaneous core needle biopsy aided in determining a pathological diagnosis of PSP, and the patient subsequently received a right lower lobectomy of the lung. The portion of central radiolucency on the CT scan corresponding to the surgical specimen was pathologically proven to be gross hematoma.

18 F-FDG PET/CT imaging: A supplementary understanding of pulmonary sclerosing pneumocytoma

Background

We sought to investigate the clinical features and ¹⁸F‐FDG PET/CT characteristics of pulmonary sclerosing pneumocytoma (PSP).

Methods

We retrospectively reviewed and comparatively analyzed ¹⁸F‐FDG PET/CT imaging results of 22 patients with diagnosed PSP in our hospital from November 2009 to September 2015.

Results

The SUV_max in tumors was positively correlated with tumor size in typical PSPs (R = 0.806, R² = 0.650, P = 0.001); however, the SUV_max in tumors had no significant correlation with tumor size of atypical PSPs (R = 0.479, R² = 0.229, P = 0.162), and the degree of correlation between them attenuated when atypical PSPs were included (R = 0.518, R² = 0.268, P = 0.011). A majority (90%) of atypical PSPs were found in males. Symptomatic patients showed a higher SUV_max than the asymptomatic group (5.68 ± 3.63 vs. 2.76 ± 1.18, respectively, P = 0.002).

Conclusion

Tumor size and clinical features may be associated with increased FDG uptake in PSPs. Morphological differences may affect the correlation between tumor size and SUV_max in PSPs. The atypical form of PSP may be more common in men.

Sclerosing pneumocytoma: Case report of a rare endobronchial presentation

RATIONALE

Sclerosing pneumocytoma is a rare benign lung neoplasm seen in middle aged adults with a female predominance. Originally thought to be vascular in origin, this rare entity is now understood to be epithelial in nature. On imaging, sclerosing pneumocytoma manifests as a well circumscribed nodule or mass, often juxtapleural in location. On histopathology, sclerosing pneumocytoma is composed of cuboidal "surface cells" and round "stromal cells," both of which show nuclear staining for thyroid transcription factor-1 (TTF-1). Here we review the existing literature on sclerosing pneumocytoma and present a case of sclerosing pneumocytoma in a highly unusual endobronchial location.

PATIENT CONCERNS

This case is a 43 year old woman who presented with chronic cough.

DIAGNOSIS

Imaging revealed a right upper lobe nodule with an endobronchial component.

INTERVENTIONS AND OUTCOMES

Endoscopic biopsy was performed, and pathologic diagnosis was confirmed.

LESSONS

Although extremely rare, endobronchial presentation of sclerosing pneumocytoma is possible, and should remain on the differential for patients with endobronchial pulmonary lesions. Pathologic tissue analysis is necessary to confirm this uncommon diagnosis.

Pulmonary sclerosing pneumocytoma, a rare tumor of the lung

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign pulmonary tumor. Usually diagnosed incidentally by chest X-ray or chest CT scan. We presented a case of PSP in a 50-year-old woman who was diagnosed with a nodular lesion in the right lung. Thoracotomy was used for the excision of the mass. Pathologic examination revealed no malignant cells. Immunohistochemical studies were performed. TTF-1 was (+), Napsin-A was found to be weakly (+). After surgical resection, the patient was followed up.

A case of pulmonary sclerosing pneumocytoma in the hilar lesion

Pulmonary sclerosing pneumocytoma (PSP) arising from the hilar lesion is extremely rare. We report an asymptomatic 70-year-old female with a thoracic tumor of unknown origin. Contrast-enhanced chest tomography showed a poorly and heterogeneously enhanced 40-mm tumor compressing the left upper lobe, bronchus, and pulmonary arteries. Positron-emission tomography did not detect abnormal integration in the tumor. Surgical resection was planned to confirm diagnosis and avoid further compression on the structures. Intraoperative findings revealed a dark red-colored tumor, projecting from the left upper lobe in the hilar lesion. Left upper lobectomy was performed through video-assisted thoracoscopic surgery to achieve complete resection and avoid contact bleeding. Immunohistochemical examination revealed the presence of PSP.

18F-FDG PET/CT characteristics of pulmonary sclerosing hemangioma vs. pulmonary hamartoma

The radiological features of pulmonary sclerosing hemangioma (PSH) and pulmonary hamartoma are poorly specified. Thus, the present study aimed to compare and analyze the characteristics of fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in PSH versus pulmonary hamartoma. ¹⁸F-FDG PET/CT characteristic findings of 12 patients with PSH and 14 patients with pulmonary hamartoma were retrospectively reviewed. A total of 12 lesions were detected from the 12 patients with PSH, of which 3 masses exhibited calcification. The mean diameter and standardized maximum uptake value (SUVmax) were 1.9±0.7 cm and 2.6±1.0, respectively, and there was no significant correlation between the lesion size and SUVmax (P>0.05). For the 14 patients with pulmonary hamartoma, 14 lesions were found, of which 4 exhibited calcification. The mean diameter and SUVmax were 1.7±0.8 cm and 1.5±0.6, respectively, and there was a significant correlation between the size and SUVmax (r=0.625, r²=0.391, P<0.05). Although there was no significant difference between the size of PSH and pulmonary hamartoma (P>0.05), the SUVmax of PSH was significantly higher than that of pulmonary hamartoma (P<0.05). Moreover, the SUVmax of 1.95 was applied as a cutoff for the diagnosis of PSH, and the resulting sensitivity and specificity for PET/CT to differentiate PSH from pulmonary hamartoma were 83.3 and 78.6%, respectively. Although the morphological features were not specific, PSH showed significantly higher FDG accumulation than pulmonary hamartoma on PET/CT imaging, which may aid the differential diagnosis. Further studies with larger populations are warranted to confirm these study results.

Analysis of the clinical differentiation of pulmonary sclerosing pneumocytoma and lung cancer

Background

Pulmonary sclerosing pneumocytoma (PSP) is a rare benign lung tumor. This study investigated the diagnostic experience of PSP and lung cancer.

Methods

This study is a retrospective study. We observed the locations of lung lesions, imaging form and clinical symptoms, and recorded the surgical complications through comparing patients with PSP and lung cancer.

Results

From December 2012 to February 2017, 187 PSP cases and 197 lung cancer cases were collected. PSP was commonly found in women (88.2%), often occurred in the left lower lobe (32.6%), and was associated with a lesion size of 10-20 mm (48.7%). PSP patients presented with cough, sputum, chest pain, and most patients had a single lesion, which could showed no clear boundary. Most PSP patients exhibited no enlargement of mediastinal lymph nodes, had no involvement of the blood vessels, and had low computed tomography (CT) values (low Hounsfield units). Lung cancers were more commonly found in men (69.0%), with the lesions scattered throughout all lobes of the lung. Cases with a tumor size >30 mm accounted for 76.2% of patients. Lung cancer patients also presented systemic symptoms, and the tumors were found to have unclear boundaries. Moreover, patients presented with enlarged mediastinal lymph nodes, high CT values, and heterogeneous internal tumor texture.

Conclusions

This study showed that PSP was rare and difficult to differentiate from lung cancer. PSP was often found in 40-70-year-old non-smoking women and most patients presented with cough and sputum. Patients often had a single lesion, which was commonly located in the left lower lobe and could have unclear boundaries. The majority of patients exhibited no enlargement of mediastinal lymph nodes and had low CT values. Therefore, our results can provide some basis for the differential diagnosis of PSP and lung cancer.

Application of Immunohistochemistry in the Diagnosis of Pulmonary and Pleural Neoplasms

CONTEXT

- A vast majority of neoplasms arising from lung or pleura are initially diagnosed based on the histologic evaluation of small transbronchial, endobronchial, or needle core biopsies. Although most diagnoses can be determined by morphology alone, immunohistochemistry can be a valuable diagnostic tool in the workup of problematic cases.

OBJECTIVE

- To provide a practical approach in the interpretation and immunohistochemical selection of lung/pleura-based neoplasms obtained from small biopsy samples.

DATA SOURCES

- A literature review of previously published articles and the personal experience of the authors were used in this review article.

CONCLUSION

- Immunohistochemistry is a useful diagnostic tool in the workup of small biopsies from the lung and pleura sampled by small biopsy techniques.

Imprint cytologic and immunocytochemical findings of sclerosing pneumocytoma

To the best of our knowledge, there is no description on immunocytochemical study of sclerosing pneumocytoma (SP) using a cell transfer method. In this article, we report imprint cytological and immunocytochemical findings of SP. Three cases of SP possessing both imprint cytological and histological materials were examined. All tumors showed well-defined margin grossly. On microscopic examination, the tumor consisted of surface and stromal round cells. Cytologically, surface and stromal round cells showed fragments or clusters of papillary configuration with low N/C ratio and cell clusters of small to medium-sized cells with high N/C ration. Immunocytochemically, surface cells showed the positive reaction for surfactant apoprotein A (SPA), but stromal round cell exhibited the negative reaction for SPA. Cytologists and pathologists should steadily recognize cytological findings of surface and stromal round cells of SP. Immunocytochemistry of SPA may be useful in the discrimination of both cells. Diagn. Cytopathol. 2017;45:274-278. © 2016 Wiley Periodicals, Inc.