Evolution of Pleural Solitary Fibrous Tumors Causing Severe Hypoglycemia after Exceptionally Long Asymptomatic Periods: Report of Two Surgical Cases.

Non-islet cell tumor hypoglycemia (NICTH) is one of the paraneoplastic syndromes manifesting severe hypoglycemia caused by aberrant production of high-molecular-weight insulin-like growth factor 2 (big-IGF2). Two surgical cases of extremely large thoracic solitary fibrous tumors (SFT) with unusual history of NICTH are presented. One case manifested severe hypoglycemia after four years of the first complete surgical resection of the tumor with potential malignant transformation, and the other case showed severe hypoglycemia after ten years of the first detection of the tumor. Meticulous laboratory testing, including serum endocrinological tests and western immunoblotting before and after surgery was performed, and both cases were diagnosed as NICTH. Both patients underwent open thoracic surgery. The patients showed normal glucose and hormone levels immediately after the resection of responsible tumors with elevated blood insulin concentration. SFTs are generally considered benign; however, life-threatening hypoglycemia can happen regardless of treatment. Careful follow-up of the tumor growth is warranted.

Our experience with solitary fibrous tumors in the chest area.

The article reports on three patients with a solitary fibrous tumor of the chest. The first patient had a tumor in the area of the dome of the right pleural cavity which was radically resected together with the chest wall around its origin. In the second case, the tumor was attached by a vascular pedicle to the lower lobe of the right lung. This tumor was resected atypically, via thoracotomy, along with a margin of healthy lung tissue at the base of its pedicle. The last patient had a tumor of the lower lobe of the right lung, surrounding the lower pulmonary vein, which did not have a clear margin of healthy lung tissue. This finding required right lower lobectomy via posterolateral thoracotomy. The presented cases describe rare types of tumors in the chest area which at the time of detection often reach large dimensions, necessitating extensive surgical procedures. Due to the biological nature of these tumors, long-term patient follow-up is advisable.

Molecular characterization of localized pleural mesothelioma.

Localized pleural mesothelioma is a rare solitary circumscribed pleural tumor that is microscopically similar to diffuse malignant pleural mesothelioma. However, the molecular characteristics and nosologic relationship with its diffuse counterpart remain unknown. In a consecutive cohort of 1110 patients with pleural mesotheliomas diagnosed in 2005-2018, we identified six (0.5%) patients diagnosed with localized pleural mesotheliomas. We gathered clinical history, evaluated the histopathology, and in select cases performed karyotypic analysis and targeted next-generation sequencing. The cohort included three women and three men (median age 63; range 28-76), often presenting incidentally during radiologic evaluation for unrelated conditions. Neoadjuvant chemotherapy was administered in two patients. All tumors (median size 5.0 cm; range 2.7-13.5 cm) demonstrated gross circumscription (with microscopic invasion into lung, soft tissue, and/or rib in four cases), mesothelioma histology (four biphasic and two epithelioid types), and mesothelial immunophenotype. Of four patients with at least 6-month follow-up, three were alive (up to 8.9 years). Genomic characterization identified several subgroups: (1) BAP1 mutations with deletions of CDKN2A and NF2 in two tumors; (2) TRAF7 mutations in two tumors, including one harboring trisomies of chromosomes 3, 5, 7, and X; and (3) genomic near-haploidization, characterized by extensive loss of heterozygosity sparing chromosomes 5 and 7. Localized pleural mesotheliomas appear genetically heterogeneous and include BAP1-mutated, TRAF7-mutated, and near-haploid subgroups. While the BAP1-mutated subgroup is similar to diffuse malignant pleural mesotheliomas, the TRAF7-mutated subgroup overlaps genetically with adenomatoid tumors and well-differentiated papillary mesotheliomas, in which recurrent TRAF7 mutations have been described. Genomic near-haploidization, identified recently in a subset of diffuse malignant pleural mesotheliomas, suggests a novel mechanism in the pathogenesis of both localized pleural mesothelioma and diffuse malignant pleural mesothelioma. Our findings describe distinctive genetic features of localized pleural mesothelioma, with both similarities to and differences from diffuse malignant pleural mesothelioma.

Localized malignant mesothelioma, an unusual and poorly characterized neoplasm of serosal origin: best current evidence from the literature and the International Mesothelioma Panel.

Localized malignant mesotheliomas (LMM) is an uncommon and poorly recognized neoplasm. Its pathologic diagnosis is often surprising in patients with serosal/subserosal based localized tumors that are clinically suspicious for metastatic lesions or primary sarcomas. Once a tumor is diagnosed as "mesothelioma", LMM is often mistaken for diffuse malignant mesothelioma (DMM). Best currently available evidence about LMM was collected from the literature and cases diagnosed by members of the International Mesothelioma Panel (IMP). One hundred and one (101) LMM have been reported in the English literature. Patients had localized tumors with identical histopathologic features to DMM. Patients ranged in age from 6 to 82 years; 75% were men. Most (82%) of the tumors were intrathoracic. Others presented as intrahepatic, mesenteric, gastric, pancreatic, umbilical, splenic, and abdominal wall lesions. Tumors varied in size from 0.6 to 15 cm. Most patients underwent surgical resection and/or chemotherapy or radiation therapy. Median survival in a subset of patients was 29 months. Seventy two additional LMM from IMP institutions ranged in age from 28 to 95 years; 58.3% were men. Sixty tumors (83.3%) were intrathoracic, others presented in intraabdominal sites. Tumors varied in size from 1.2 to 19 cm. Median survival for 51 cases was 134 months. Best evidence was used to formulate guidelines for the diagnosis of LMM. It is important to distinguish LMM from DMM as their treatment and prognosis is different. A multidisciplinary approach is needed for the diagnosis of LMM as it shows identical histopathology and immunophenotype to DMM.

Surgical outcomes and clinical courses of solitary fibrous tumors of pleura.

AIM: This study's aim is to define the clinicopathological and surgical outcomes, clinical courses, and results of long-term follow-up of cases that underwent surgical treatment for solitary fibrous tumors of the pleura (SFTp). SUBJECTS AND METHODS: Clinical and long-term follow-up records of 16 consecutive patients who had surgery for SFTp between 2006 and 2016 were reviewed in the retrospective chart review. There were nine males (56%) and seven (44%) females with an average age of 60.5 ± 17.1 (range 30-87 years). Etiological factors, diagnostic procedures, clinical and surgical outcomes, 5-year overall survival (OS), and disease-free survival (DFS) in these patients were researched. RESULTS: There was no remarkable common etiological factor. Nine of the cases were asymptomatic. Other symptoms were chest pain, dyspnea, cough and hypertrophic osteoarthropathy, respectively. Thoracotomy for the removal of pleural mass was carried out in 15 (94%) cases. Additional resection procedures included the chest wall resection in two cases and lobectomy in two. Video-assisted thoracoscopic surgery (VATS) resection was performed in one (6%) case. Complete surgical excision was performed in 74% of cases. Nineteen percent of cases were malignant SFTp (mSFTp). One of the mSFTp cases died in the 19th month after the diagnosis. The mean follow-up time was 50.6 ± 34.2 months (2--114 months). Mean survival of mSFTp patients was 40.6 ± 19.08 months (19--55 months) and that for benign SFTp (bSFTp) was 52.9 ± 37.05 months (2--114 months). Five-year OS--DFS were 93.5% and 74%, respectively. CONCLUSION: SFTp is an uncommon benign neoplasm but it can have malignant features. Even in the case of recurrence, the main treatment is total surgical excision. Oncologic treatments can be tried in unresectable and metastatic cases. VATS can be used in surgical total excision for small diameter and appropriate tumors. Understanding the nature of these tumors, immunohistochemical, and genetic studies may be a guide in future.

Extrapleural solitary fibrous tumor: A distinct entity from pleural solitary fibrous tumor. An update on clinical, molecular and diagnostic features.

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm that was originally described to be localized in the pleura, but thereafter, this has been reported in several anatomic sites. Although the etiology of the neoplasm remains largely unknown, the pathogenesis seems to be related to an NAB2-STAT6 fusion gene due to paracentric inversion on chromosome 12q13. The diagnosis of extrapleural SFT is challenging, owing to its rarity, and requires an integrated approach that includes specific clinical, histological, immunohistochemical, and even molecular findings. Histologically, extrapleural SFT shares morphological features same as those of the pleural SFT because it is characterized by a patternless distribution of both oval- and spindle-shaped cells in a variable collagen stroma. In addition, morphological variants of mixoid, fat-forming, and giant cell-rich tumors are described. A correct diagnosis is mandatory for a proper therapy and management of the patients with extrapleural SFT, as extrapleural SFT is usually more aggressive than pleural form, particularly cases occurring in the mediastinum, retroperitoneum, pelvis, and meninges. Although SFT is usually considered as a clinically indolent neoplasm, the prognosis is substantially unpredictable and only partially related to morphological features. In this context, cellularity, neoplastic borders, cellular atypias, and mitotic activity can show a wide range of variability. We review extrapleural SFT by discussing diagnostic clues, differential diagnosis, recent molecular findings, and prognostic factors.

[Doege-Potter syndrome with giant malignant solitary fibrous tumour of the pleura]. / Doege­Potter-szindróma a mellhártya óriás malignus szoliter fibrosus tumorával.

Infrequent solitary fibrous tumours of the pleura are associated with hypoglycaemia only in a few percent of the cases; this condition is called Doege-Potter syndrome, named after its first descriptors. Our 63 years old male patient has previously undergone clinical treatment for intrathoracic fluid accumulation on the left side caused by a giant tumour-like mass in the lower left lobe detected by CT scan. In the course of further investigations performed due to increasing load-induced dyspnoea, lung core biopsy verified low grade sarcoma in the tumour. Tumour board suggested surgery. The patient was transferred from the intensive care unit into the operation theater due to increasing dyspnoea and repeated hypoglycaemic periods in rapidly worsening general condition. Pneumonectomy and removal of the tumour was performed on the left side. Histology showed solitary fibrous tumour of the pleura corresponding to Doege-Potter syndrome. The patient was discharged without complications and underwent adjuvant chemotherapy due to pleural dissemination of the tumour observed intraoperatively. One year after surgery the patient underwent surgical removal of a locally recurrent tumour. In spite of repeated chemotherapy local and multiplex contralateral pulmonary progression was observed. Three-year survival was noted from the time of the first surgery. Orv Hetil. 2018; 159(41): 149-153.

Solitary fibrous tumour of pleura: CT differentiation of benign and malignant types.

AIM: To analyse and compare the computed tomography (CT) features of benign and malignant types of histopathologically proven cases of solitary fibrous tumours of pleura (SFTP). MATERIALS AND METHODS: Retrospective analysis of preoperative CT images of 28 cases of histopathologically proven and classified SFTP from three participating institutions was performed. Patient demographics and lesion characteristics including size, borders, presence of a pedicle, extension into the fissure, attenuation, enhancement, pleural effusion, and calcifications were recorded and correlated with the final histopathological diagnosis. Type and results of preoperative biopsy were also recorded. Follow-up imaging and the clinical charts were reviewed to identify recurrence. RESULTS: Out of 28 cases (15 women and 13 men), 18 were proven to be benign and 10 were malignant. The mean age of patients was 58.1±15.9 and 66.5±11.8 years (p=0.1564) for benign and malignant tumours, respectively. The median (interquartile range) diameter was 6.05 (3.2-10.9) cm for benign and 15.7 (7.1-17.5) cm for malignant type tumours (p=0.0291). Tumours had lobulate borders in 28% (5/18) of benign cases and in 80% (8/10) of malignant cases (p=0.0163). Extension into adjacent fissure was seen in 22% (4/18) of benign lesions and 40% (4/10) of malignant lesions (p=0.40). A pedicle was present in 17% (3/18) of benign and 10% (1/10) of malignant lesions (p=1). Heterogeneous attenuation was present in 61% (11/18) of benign and 90% (9/10) of malignant lesions (p=0.19). Calcification was present in 17% (3/18) of benign tumours and in 70% (7/10) of malignant tumours (p=0.0113). Pleural effusion was present in 6% (1/18) of benign and 40% (4/10) of malignant lesions (p=0.04). Only 1/13 preoperative fine-needle aspirates yielded diagnosis of SFTP. Preoperative diagnosis of SFTP was made in all cases (11/11) with core biopsies. At follow-up (1-10 years, mean 3 years), local recurrence occurred in 3/6 (50%) patients with malignant SFTP and in none of the 10 patients with benign SFTP. CONCLUSION: No definite imaging feature to differentiate benign from malignant SFTP was found. Large size, lobulate borders, presence of calcification, and ipsilateral pleural effusion were the only CT features predictive of malignancy. In suspected cases, core biopsies should be performed rather than fine-needle aspiration.

Solitary Pleural Fibroma: A Case Report and Review of Literature.

Solitary fibrous tumors ofthe pleura (SFTP) are uncommon. They tend to be discovered incidentally or during workup for unexplained cough or paraneoplastic effects. It is important to recognize the entityand perform a surgical excision because of the possibility of subsequent malignant transformation and local compressive effects. We present the case of a SFTP discovered on chest imaging. Our patient had surgical excision with good response. A review of the literature is also presented.

Challenges in diagnosis and management of giant solitary fibrous tumour of pleura: a case report.

BACKGROUND: Majority of patients with solitary fibrous tumours of the pleura (SFTP) are asymptomatic. Acute presentation with symptoms resulting from mass effect due to rapid expansion of tumour size has not been reported before. CASE PRESENTATION: This report chronicles the case of a giant SFTP in a 76-year-old lady who presented with acute onset of haemoptysis, left-sided pleuritic chest pain and hoarseness of voice. Her chest radiograph showed a large left upper hemithorax mass with an ipsilateral effusion. Computed tomography (CT) scan of the thorax confirmed the presence of a pleural-based mass lesion in the left apex measuring 9.7 cm with close apposition to the aortic arch. The mass demonstrated neovascularization and there was also presence of a moderate-sized heterogeneous-appearing left pleural effusion. Thoracocentesis yielded deeply haemoserous pleural fluid with a pleural aspirate hematocrit closely approaching that of peripheral blood hematocrit and alongside a 2 unit decrease in haemoglobin, was indicative of a haemothorax. Repeat CT 10 days from initial presentation showed reduction in size of the left apical mass as well as resolution of the left effusion. This was consistent with the occurrence of an intra-tumoural bleed resulting in rapid increase in the size of the SFTP, causing rupture of superficial blood vessels on the tumour surface (haemothorax) and consequential compression of the lung parenchyma (haemoptysis) and left recurrent laryngeal nerve (hoarseness of voice). The patient eventually underwent an uneventful surgical resection. CONCLUSION: A benign SFTP can present acutely with compressive symptoms as a result of spontaneous intra-tumoural bleed causing sudden increase in its size. It is important to allow temporal regression of these acute changes before deciding on surgical resectability.

Solitary fibrous tumor of the pleura: morphogenesis and progression. A report of 36 cases.

PURPOSE: We attempted to identify the exact point of tumor eruption of a solitary fibrous tumor of the pleura (SFTP). METHODS: We morphologically classified 36 SFTPs into 5 categories. Type A showed a connection that included a bloodstream with the pleura on both sides. Type B only showed a connection that included a bloodstream with the visceral pleura, and had a non-bloodstream connection with the parietal pleura. Type C only showed a connection that included a bloodstream with the visceral pleura, and had no connection with the parietal pleura. Type D showed a non-bloodstream connection with the visceral pleura, and only showed a connection that included a bloodstream with the parietal pleura. Finally, type E had no connection with the visceral pleura, and only showed a connection that included a bloodstream with the parietal pleura. The clinicopathological profiles of the tumors were investigated according to their type. RESULTS: The distribution of the 36 SFTPs was as follows: A (19 %), B (6 %), C (67 %), D (0 %) and E (8 %). The tumors categorized as type A tended to be large in size. CONCLUSIONS: SFTPs commonly arise from the visceral pleura and in accordance with tumor progression they will form a non-bloodstream connection with the parietal pleura. Finally, a vascular pedicle will arise with the parietal pleura.

Prognostic factors in solitary fibrous tumors of the pleura.

BACKGROUND: Solitary fibrous tumors of the pleura (SFTP) are rare neoplasms originating from submesothelial mesenchymal cells with fibroblastic differentiation. The clinical behavior of SFTPs is mostly benign; however, up to 20% of patients develop local recurrence and/or distant metastasis. Although different risk-stratification models have been described, definitive criteria to predict a malignant clinical course of SFTP are still lacking. METHODS: In a retrospective analysis at a single-institution, 25 patients with histologically proven SFTP were identified. Clinicopathologic and survival data were collected and pathologic sections reviewed. Different markers and risk-stratification models were correlated with disease- and overall-free survival by Kaplan-Meier analysis. RESULTS: Of 25 SFTP, 8 tumors (32%) were classified as malignant according to the World Health Organization criteria. Three patients (12%) developed recurrence. Cohort median follow-up was 28 mo, and median overall survival was 160 mo. Comparison of proliferation markers showed higher mitosis count per high-power field and MIB-1 labeling index (MIB) in malignant compared with nonmalignant SFTP. MIB was identified as a predictor for disease-free survival. Applying the previously reported classifications to categorize SFTP according to the probability to show malignant behavior, significant differences in disease-free survival were also present in our cohort. CONCLUSIONS: In the present analysis of rare SFTP, previously proposed staging systems were applicable for prediction of disease-free survival. Independently of treatment, MIB was the only sole predictive marker. A prospective multi-institutional database could be helpful in establishing detailed predictive criteria in patients diagnosed with SFTP.

Determinants of outcome of solitary fibrous tumors of the pleura: an observational cohort study.

BACKGROUND: Solitary fibrous tumors of the pleura (SFTP) are rare and their long-term outcome is difficult to predict, as there are insufficient data which allow accurate characterization of the malignant variant. Thus the aim of this study was to describe the outcome and possible determinants of malignant behavior of SFTPs. METHODS: Data were collected retrospectively from medical records of patients treated at the University Hospital Zurich from 1992 to 2012. Kaplan-Meier and Cox regression analysis were performed to define disease-free survival time (defined as survival without tumor-recurrence or tumor-related death) using the classical histo-morphological criteria (tumor size, localization, pedunculation, tumor necrosis or hemorrhage, mitotic activity and nuclear pleomorphism) and immunohistochemical parameters. RESULTS: 42 patients (20 males) with SFTP (median (IQR) age 62 (56-71) years) could be identified. SFTP were associated with symptoms in 50% of all cases. Complete resection was achieved by video-assisted thoracic surgery or thoracotomy in 20 and 22 patients, respectively. Three SFTP-related deaths (7.1%) and four tumor recurrences (9.5%) were observed. Mean disease-free survival time was 136.2 (± 13.1) months, and 2-, 5- and 10-year disease-free survival was 91%, 84%, and 67%, respectively. Mean disease-free survival inversely correlated with the mean tumor diameter, number of mitotic figures and proliferation rate (Ki-67 expression). Other criteria (tumor necrosis, atypical localization, sessile tumor, and pleomorphism) were not statistically significant prognostic parameters. CONCLUSIONS: Patients with large SFTP with a high mitotic index and high proliferation rate should be followed-up closely and over a prolonged time period in order to recognize recurrence of the SFTP early and at a treatable stage. Future research on this topic should focus on the prognostic role of immunohistochemistry including Ki-67 expression and molecular parameters.

Solitary fibrous tumor of the pleura with air cystic component.

We present an uncommon case of a solitary fibrous tumor of the pleura with the appearance of an air-containing cystic mass. We discuss the differential diagnosis through the imaging findings, the hypothetical origins of the air component, and the possible relationship between the air component and the aggressivity of the tumor.

Solitary fibrous tumours of the pleura: do we need a different perspective on malignancy?

OBJECTIVES: Solitary fibrous tumours of the pleura (SFTP) are historically considered to be benign soft tissue neoplasms. However, a clinical relevant number of these neoplasms have malignant histological features. The objective of this study was to evaluate the percentage of SFTP presenting unfavourable clinical behaviour in order to predict negative long-term outcome. METHODS: A retrospective review of 74 patients treated at 4 hospitals between 1990 and 2013 was performed. The median follow-up was 10 years (range: 1-20 years). Risk of tumour recurrence and metastases (unfavourable clinical behaviour) with regard to histology using the Kaplan-Meier and Cox proportional hazards methods. RESULTS: The mean age was 61 years (SD 12.75 years). There were 31 male patients (58%) and 43 female patients (42%). Tumour size ranged from 1 to 30 cm (mean 9.09 cm; SD 6.22 cm). Complete resection (R0) was achieved by minimally invasive thoracoscopic resection in 29% and thoracotomy in 57%; 25% of SFTPs showed histological evidence of malignancy, according to England criteria. Recurrence occurred in 21% and 10% of patients had metastases; 83% of patients with metastases and 39% of patients with recurrence died within 5 years. The median recurrence-free survival for histologically benign SFTP was not reached, compared to 8 years for malignant SFTP. The five-year overall survival rate was 84%. Mitotic rate ≥1/10 HPF, high cellularity, nuclear atypia, Ki-67 level >5% and poorly circumscribed (sessile) growth pattern were associated with poor long-term outcome. CONCLUSIONS: Pathological differentiation of SFTP morphology into pedunculated, well circumscribed and poorly circumscribed (sessile) growth pattern is recommended. Due to the misleading classification into histologically benign and malignant, all unpedunculated SFTP should be classified as potentially aggressive. Lifelong follow-up is mandatory.

Pleural Solitary Tumors - Long-Term Prognosis Related To Surgery And Clinicopathological Criteria.

INTRODUCTION: Pleural solitary fibrous tumors (SFTs) are indolent mesenchymal neoplasias, generally with good prognosis, for which complete surgical resection is the gold standard. However, local recurrences and distant metastases are reported at variable rates. Risk-assessing criteria and models determining recurrence and metastatic risk have been proposed, and can impact on patient follow-up strategies. METHODS: We conducted an observational study comprising a 12 years period to characterize a cohort of 20 surgically resected thoracic SFTs, and to retrospectively assess the prognostic value of England's histology criteria and Demicco's 4-tier model. RESULTS: All tumors were pleural-based, 12 patients were women, and the mean age at diagnosis was 62.8 years. The median duration of follow-up was ten years, and at the end of the follow-up, all patients were alive, and no distant metastases were reported. Three cases (15%) had local recurrence at the median time of 89.3 months/7.4 years. The only case with an incomplete surgical resection relapsed. Collectively, tumors with worst prognostic features, specifically a positive margin or tumors with malignant histology or non-low-risk features, according to England's and Demicco's models, respectively, were associated with recurrence. CONCLUSION: These results confirm the importance of complete surgical resection of SFTs, and show that risk stratification criteria and models can predict important surgical outcomes such as recurrence. Moreover, they support a risk-based follow-up schedule, as patients with higher relapse risk can benefit from close follow-up.

Single-incision video-assisted thoracoscopic resection of a pedunculated solitary fibrous tumor of the pleura: case report.

In this report, we describe the surgical resection of a pedunculated solitary fibrous tumor of the pleura (SFTP) by single-incision thoracoscopic surgery (SITS). SITS may be a suitable surgical option for pedunculated SFTPs.

Anesthetic management of thoracotomy for massive intrathoracic solitary fibrous tumor of the pleura: a case report.

BACKGROUNDS: Solitary fibrous tumor of the pleura (SFTP) is a rare thoracic tumor and usually asymptomatic. Massive SFTP may affect adjacent organs and tissues including pulmonary vasculature, bronchus and heart. A thoracotomy for massive SFTP is necessary in severe case. Therefore, it is important for anesthesiologists to understand the condition of patients with massive SFTP and develop an appropriate anesthetic management strategy. A 76-year-old woman with massive SFTP presented to our clinical center and was evaluated as requiring thoracotomy. She received multidisciplinary cooperation treatment from the radiology, cardiac, thoracic surgery and anesthetic teams. The perioperative management of anesthesiologists played a crucial role in the great prognosis of this woman. CONCLUSIONS: This case report demonstrates the importance of comprehensive and meticulous perioperative management and provides guidance to the multidisciplinary team on the potential risk and the rational treatment strategy of patients with massive SFTP during the perioperative period.