Primary Sarcoma of the Mediastinum: A Report of 16 Cases Referred to the British Columbia Cancer Agency

Proton Beam Therapy for Unresectable Mediastinal and Pericardial Spindle Cell Sarcoma: A Case Report

Unresectable mediastinal soft tissue sarcomas are often aggressive and associated with a poor prognosis. A 17-year-old male presented with progressive fatigue, shortness of breath, and heart palpitations secondary to an extensive mass involving the mediastinum and pericardium. He was treated with chemotherapy per protocol Children's Oncology Group Protocol ARST0332 and proton beam therapy to the involved mediastinum, pericardium, and heart. At the 5-year follow-up evaluation, he remained disease-free on surveillance imaging. An echocardiogram revealed a 55% to 60% left ventricular ejection fraction. Given the patient's extended survival, we present the oncologic rationale for treatment and considerations of late toxicity.

Mediastinal Liposarcoma With Anterior and Posterior Mediastinal Involvement: A Thoracic Oncovascular Case Report

A 64-year-old patient presented with shortness of breath and chest pressure. The initial examination was unremarkable, and a chest X-ray revealed a large mediastinal mass. Computed tomography (CT) scan demonstrated a lobulated mediastinal mass involving the great vessels and mass effect on the trachea, esophagus, and heart. A CT-guided biopsy showed a monotonous, evenly spaced population of mature, normal-appearing adipocytes consistent with a well-differentiated lipoma-like liposarcoma/atypical lipomatous tumor. The patient underwent a median sternotomy with en bloc tumor resection without adjuvant chemoradiation. Three-year follow-up CT imaging shows no evidence of tumor recurrence.

The Rarest of Rare Thymic Lesions: A 10-Year Surgical Pathology Experience

The thymus is a specialized primary lymphoid organ located in the midline pre-vascular mediastinum. The organ is the site of various pathological processes, neoplastic and not, whose rarity has not allowed in-depth studies on clinical or histological features of rarest and unusual variants. Herein, we report a 10-year Padova experience in the surgical pathology of the thymus, focusing on the pathological description of nonneoplastic lesions and rare epithelial and mesenchymal tumors recorded in our database, which comprises over 600 thymectomies. The extrapolated rare cases have been categorized into four groups that included 15 cysts, 18 carcinomas, 5 neuroendocrine tumors, and 2 soft tissue tumors. The cases are described from a clinical and pathological point of view and discussed in dedicated sections with a review of the most important literature. In this case, review series, we aim to update the epidemiology of these rare entities, improve diagnostic awareness, and finally, promote a collaborative network between referral centers.

Ipilimumab and Pembrolizumab Mixed Response in a 41-Year-Old Patient with SMARCA4-Deficient Thoracic Sarcoma: An Interdisciplinary Case Study

SMARCA4-deficient thoracic sarcoma is a newly described entity of thoracic sarcomas with a poor prognosis, defined by poorly differentiated epithelioid to rhabdoid histomorphology and SMARCA4 gene inactivation. We present a case of a SMARCA4-deficient thoracic sarcoma in a 41-year-old male with a smoking history who presented with an upper anterior mediastinal mass, after seeking medical evaluation for increasing thoracic pain, odynophagia, and dizziness. The biopsy confirmed a large cell tumor with an epithelioid to rhabdoid histomorphology, positive for EMA, CD99, vimentin, TLE1, INI1, PAS-positive cytoplasmic granules, and PD-L1 (100% of tumor cells). High TMB and HRD scores were displayed in the tumor. The histology and immunophenotype of the mass were in line with the diagnosis of SMARCA4-deficient thoracic sarcoma. In the course of his treatment, the patient showcased a partial response to pembrolizumab and the combination of pembrolizumab and ipilimumab. This case report highlights the importance of recognizing SMARCA4-deficient thoracic sarcoma as an individual entity and supports the importance of checkpoint inhibition therapy for SMARCA4-deficient thoracic sarcomas, particularly in cases with a high TMB and PD-L1 expression.

Primary Intrathoracic Sarcomas: A Review of Cross-sectional Imaging and Pathology

The most common sarcomas in the thorax are metastasis from an extrathoracic primary malignancy. Primary intrathoracic sarcomas are rare albeit aggressive malignancies that are diagnosed on histopathology. Although a few imaging characteristics have been described that are common to sarcomas, it is still a diagnosis of exclusion as other tumors are much more common. Like elsewhere, primary thoracic sarcomas are also classified according to their histologic features. They are a rare group of tumors that can arise from the mediastinal structures, lung, pleura, or chest wall. On imaging, differentiating these from more common malignancies like lung cancer is difficult and often requires multimodality workup and tissue sampling. A few sarcomas are very specific to their locations, such as angiosarcoma in the right atrium, leiomyosarcoma in the pulmonary artery, where imaging has high accuracy for the diagnosis. Despite being nonspecific in a majority of cases, imaging plays a pivotal role in determining the organ of origin, tumor extent, invasion of adjacent structures, and thus help to assess the surgical resectability. Although sarcomas arising from chest wall are the most common primary sarcomas in the chest, they are excluded from this review to focus only on primary intrathoracic sarcomas. The article provides a comprehensive imaging and pathology review of the rare primary intrathoracic sarcomas, including but not limited to angiosarcoma, Kaposi sarcoma, fibrosarcoma, malignant transformation of fibrous tumor of pleura, sarcomatoid mesothelioma, leiomyosarcoma, and malignant small round blue cell tumors.Key points:Primary intrathoracic sarcomas are rare but clinically important.Imaging helps to determine local extent, invasion, metastases and appropriate site/mode of biopsy.Role of pathology is paramount in diagnosis and guiding treatment based on immunogenetic/molecular typing.

Radiation Therapy in Resectable Intrathoracic Sarcomas. A Rare Cancer Network Study

PURPOSE

Intrathoracic sarcomas (ITS) are considered rare tumors and have a dismal prognosis. We investigated outcomes and risk factors for local control (LC), disease-free survival (DFS), and overall survival (OS) in patients with resected nonmetastatic ITS treated with or without adjuvant radiation therapy (RT) and/or chemotherapy.

METHODS AND MATERIALS

Patients from the Rare Cancer Network database were studied. A Kaplan-Meier estimate was used to assess survival curves, and Cox proportional hazards regression was used to assess risk factors for LC, DFS, and OS.

RESULTS

Between 2000 and 2017, 121 patients met inclusion criteria. The primary site was lung in 30%, mediastinum in 34%, and pleura in 36%. Thirty-nine percent and 32% received RT and chemotherapy. Median follow-up was 34 months (range, 2-141). LC, DFS, and OS at 10 years were 52%, 18.7%, and 7.2%, respectively. In multivariate analysis, RT (P = .003) and R1 margin status (P = .041) retained a significant association with LC. Only R1 resection (P = .002) remained associated with an increased risk of death in multivariate analysis. Overall, 7 patients (6%) developed grade 3 treatment-related chronic toxicity events.

CONCLUSIONS

This joint analysis revealed that OS remains modest in this group of patients, mainly given by the high risk of local and distant failure. Our results suggest that resected ITS can benefit from adjuvant RT.

Treatment Approaches and Outcomes for Primary Mediastinal Sarcoma: Analysis of 976 Patients

BACKGROUND

Primary mediastinal sarcomas are rare and deadly. Our objective was to describe the clinicopathological features, treatment strategies, and overall survival outcomes for a contemporary cohort of patients diagnosed with primary mediastinal sarcoma in the United States.

METHODS

We queried the National Cancer Database for cases of mediastinal sarcoma diagnosed from 2004 to 2012. Five-year overall survival (OS) was examined using the Kaplan-Meier method. Differences in OS were assessed using log-rank analysis and Cox proportional hazards regression.

RESULTS

The mean age of diagnosis was 53 years (range, 0 to 90) with a male predominance (59.2%). The most common histological subtype was hemangiosarcoma (27.1%). Fewer than half of patients underwent surgery (48.9%), and 19.7% of patients had no treatment. For all patients, OS was 14.8%. The best unadjusted OS was seen in patients treated with surgery and radiation (40.1%); untreated patients had the worst unadjusted OS (4.2%). Of those who underwent surgery (n = 477, 48.9%), OS was significantly better for those who achieved an R0 resection (30.1% versus 18.9%; p = 0.002). In multivariable analysis, surgery combined with radiation therapy was again associated with the best survival (HR, 0.24; 95% CI, 0.16 to 0.36). Other factors associated with improved OS included younger age, fewer comorbidities, and leiomyosarcoma histology. Worse OS was associated with poorly differentiated or undifferentiated grade, metastases, treatment in the New England region, and having Medicaid or no insurance. Sex and tumor size had no effect on OS.

CONCLUSIONS

The 5-year OS for primary mediastinal sarcoma is poor. Surgical resection can be successful and should be considered whenever possible.

An analysis of clinical characteristics and patient outcomes in primary mediastinal sarcomas

BACKGROUND

Published data concerning primary mediastinal sarcomas are limited to small-sized retrospective series.  This study reviewed the clinical outcomes of these cases from the SEER (surveillance, epidemiology and end results) database.

METHODS

Primary mediastinal sarcomas (1988 - 2013) were assembled from the SEER database. The incidence and 10-year cancer-specific survival rates were compared to other primary mediastinal malignancies (thymic carcinoma, germ cell tumors, neurogenic tumors, Hodgkin / non Hodgkin lymphomas) as well as to non mediastinal sarcomas.

RESULTS

A total of 204 patients were recruited into this cohort. Multivariate analysis showed better overall survival for patients with younger age at diagnosis, low grade [hazard ratio 0.427 (95% CI: 0.224-0.814; P= 0.010)], posterior mediastinum location [hazard ratio 0.458 (95% CI: 0.268-0.781; P= 0.004)], node negative disease [hazard ratio 0.463 (95% CI: 0.232-0.923; P= 0.029)] and surgical treatment [hazard ratio 0.488 (95% CI: 0.336-0.709; P <0.0001)]. Compared to other mediastinal malignancies, primary mediastinal sarcomas have the worst 10-year overall survival. Similarly compared to non mediastinal sarcomas, primary mediastinal sarcomas have worse 10-year overall survival (23% versus 55%).

CONCLUSION

Primary mediastinal sarcoma is a rare entity with worse prognosis compared to non-mediastinal counterparts. Surgical resection plays a particularly important role in the management.

Morphological spectrum of mediastinal lesions with special emphasis on evaluation of needle biopsy: An experience from a tertiary care hospital

Background & objectives:

Mediastinal lesions are uncommon and are infrequently encountered in routine clinical practice. Hence, there is a need for more elaborate studies of mediastinal lesions to make the pathologists and clinicians aware of the large spectrum of these lesions. The present study describes the histomorphological spectrum of various mediastinal lesions in a tertiary care hospital in India, along with the discussion of some unusual and interesting cases. Considering the limited diagnostic material obtained in guided biopsies, the adequacy of such tissue for providing a definite opinion was also evaluated.

Methods:

This was a retrospective study performed on 125 mediastinal masses diagnosed on surgically resected specimens as well as needle biopsies over a period of two years (January 2012-December 2013). A few cases had inadequate diagnostic material, making a total of 116 cases which were further evaluated.

Results:

A total of 116 patients of mediastinal lesions were included in the study. Most of the lesions were in 21-30 yr age group, with male:female ratio of 1.7:1. Anterior mediastinal compartment was most commonly involved. Majority of the cases (62.1%) were of neoplastic nature, with benign tumours (34.5%) being more common than malignant ones (27.6%). Thymoma followed by lymphoma constituted the most common mediastinal tumours. One-third of the total cases were diagnosed on needle biopsy samples. All cases where needle biopsy was followed by resection specimen showed concordant diagnosis. The percentage adequacy of biopsy was 91.7 per cent and the diagnostic accuracy was 100 per cent.

Interpretation & conclusions:

This study provides the histomorphological spectrum and biological diversity of the mediastinal lesions. It also emphasizes that biopsy is sufficiently adequate, with the help of a comprehensive immunohistochemistry panel, for providing a definite diagnosis in majority of cases.

Primary mediastinal pleomorphic liposarcoma involving the superior vena cava

Primary mediastinal liposarcomas are extremely rare. They are primarily diseases of adults; however, they may be encountered in children. They are characterized by their large size and variable histologic subtypes, which correlate with clinical behavior and prognosis. Although the overall prognosis is poor, it is dependent upon the histologic subtype and completeness of surgical excision. Herein we present a case of a primary mediastinal pleomorphic liposarcoma in a 49-year-old male who received an en-bloc resection and superior vena cava replacement with Gortex graft. The patient has been disease-free after surgery for over 14 months.

Primary synovial sarcomas of the mediastinum: a systematic review and pooled analysis of the published literature

Background. The aim of this systematic review is to attempt to provide a descriptive analysis for cases of synovial sarcoma (SS) arising in the mediastinum and to analyze prognostic factors. Methods. We performed PubMed database search in July 2013. Twenty-two studies, which included 40 patients, form the basis of this review. Demographic and disease-related factors were analyzed for possible influence on survival. Findings were compared with extremity SS studies reported in literature. Results. Sixteen cases (40%) presented with locally advanced unresectable disease, 2 (5%) with metastatic disease, and 22 (55%) with localized resectable disease. Median tumor size was 11 cm (range: 5–20 cm). Thirty patients were assessable for survival and had a 5-year OS of 36%. Completeness of resection was the only factor associated with significant improvement in OS (5-year survival of 63% and 0% in favor of complete resection, P = 0.003). Conclusion. Mediastinal SS is associated with poor prognosis as more cases are diagnosed at an advanced stage and with larger tumor size compared to extremity SS. Complete surgical resection is the only identified factor associated with better prognosis and may result in survival outcomes that are comparable with those for localized SS of the extremity.

Primary mediastinal sarcoma: surgical outcomes of 21 cases

OBJECTIVES

Primary sarcomas of the mediastinum are relatively rare. This article reviews the surgical outcomes of 21 cases diagnosed with localized mediastinal sarcomas receiving multidisciplinary treatment modalities in Sichuan province, China, from January 1996 to January 2011.

METHODS

Twenty-one cases of histologically diagnosed primary mediastinal sarcoma undergoing surgical treatment were reviewed retrospectively. Disease-free survival (DFS) and overall survival (OS) were statistically analysed. All the patients presented with localized tumours consisting of 5 females and 16 males with a median age of 41.0 years (range: 9.0-68.0 years). Among all cases, 17 (81.0%) had an Eastern Cooperative Oncology Group performance status score of ≤1 at diagnosis. Eight (38.1%) underwent macroscopically complete resection (R0-R1) and 13 (61.9%) had incomplete resection (R2). Ten (47.6%) received postoperative radiotherapy and 7 (33.3%) postoperative chemotherapy.

RESULTS

The median DFS was 17 months (range: 0.4-79.8 months) and the median OS was 27.2 months (range: 0.4-79.8 months). Patients receiving complete resection showed significantly improved DFS (P = 0.031) and OS (P = 0.035) compared with those with incomplete resection. Neither postoperative radiotherapy nor chemotherapy significantly improved DFS (P = 0.770, P = 0.756) or OS (P = 0.905, P = 0.738). However, 7 patients (R2) and 2 (R0-R1 and grade 3) had improved local control with a local recurrence-free survival of 28.9 months (range: 7.6-73.2 months).

CONCLUSIONS

Complete resection should be preferentially attempted compared with incomplete resection and postoperative radiotherapy might yield good local control.

Synovial sarcoma presenting with huge mediastinal mass: a case report and review of literature

Background

Synovial sarcoma presenting in the mediastinum is exceedingly rare. Furthermore, data addressing optimal therapy is limited. Herein we present a case where an attempt to downsize the tumor to a resectable state with chemotherapy was employed.

Case presentation

A 32 year female presented with massive pericardial effusion and unresectable huge mediastinal mass. Computed axial tomography scan - guided biopsy with adjunctive immunostains and molecular studies confirmed a diagnosis of synovial sarcoma. Following three cycles of combination Ifosfamide and doxorubicin chemotherapy, no response was demonstrated. The patient refused further therapy and had progression of her disease 4 months following the last cycle.

Conclusion

Synovial sarcoma presenting with unresectable mediastinal mass carry a poor prognosis. Up to the best of our knowledge there are only four previous reports where primary chemotherapy was employed, unfortunately; none of these cases had subsequent complete surgical resection. Identification of the best treatment strategy for patients with unresectable disease is warranted. Our case can be of benefit to medical oncologists and thoracic surgeons who might be faced with this unique and exceedingly rare clinical scenario.

Liposarcomas of the mediastinum and thorax: a clinicopathologic and molecular cytogenetic study of 24 cases, emphasizing unusual and diverse histologic features

Liposarcoma rarely occurs in the mediastinum, and most reports predate the current genetically based classification system. We report the clinicopathologic and molecular genetic features of a series of thoracic liposarcomas identified over a 60-year period. Twenty-four confirmed cases were reclassified using the most recent World Health Organization classification. Fluorescent in situ hybridization for CPM amplification and/or DDIT3 rearrangement was performed on selected cases. The 24 cases occurred in 13 men and 11 women (mean age, 53 y; range, 15 to 73 y) and arose in all mediastinal compartments. All subtypes were encountered with 8 well-differentiated liposarcomas, 6 dedifferentiated liposarcomas (3 of 6 confirmed CPM+), 7 pleomorphic liposarcomas (2 of 7 confirmed CPM-, 1 of 7 confirmed DDIT3-), 2 myxoid liposarcomas, and 1 unclassifiable liposarcoma (CPM- and DDIT3-). Unusual histologic features included myxoid well-differentiated liposarcoma mimicking myxoid liposarcoma (2 cases), lipoleiomyosarcoma (1 case), dedifferentiated liposarcoma with "meningothelial"-like dedifferentiation, differentiated myxoid liposarcoma mimicking well-differentiated liposarcoma (CPM-), and pleomorphic liposarcoma with epithelioid and myxoid change. Follow-up information was available for 19 patients (mean, 55 mo; range, 8 to 252 mo). Outcome was strongly associated with histologic subtype, with death from disease occurring in 1 of 6 well-differentiated, 1 of 4 dedifferentiated, 5 of 7 pleomorphic, and 2 of 2 myxoid liposarcomas. The mediastinum shows a preponderance of uncommon subtypes and unusual morphologic variants. Correct classification has important implications, with most patients with well-differentiated/dedifferentiated liposarcoma having a protracted clinical course, in contrast to the more rapid disease progression seen in patients with myxoid and pleomorphic liposarcoma.