Clinical and pathological features of primary renal synovial sarcoma: analysis of 64 cases from 11 years of medical literature

Primary Synovial Sarcoma of the Scrotum

The report outlines a case of synovial sarcoma in the scrotal region. A 36-year-old male presented with a scrotal swelling. The lesion was completely resected, whereas the histopathologic examination revealed a spindle cell tumor. The tumor stained positive for pancytokeratin, AE1/AE3, epithelial membrane antigen (EMA), TLE-1, CD99, and BCL-2. The cytogenetic testing showed a chromosomal translocation in the SS18 gene at 18q11.2, consistent with the diagnosis of primary synovial sarcoma. A year later, the patient developed liver, vertebrae, and lung metastasis, which was treated with systemic chemotherapy. Treatment failed to improve the hepatic lesion that was then resected, while the spine and lung lesions were followed by radiotherapy. The patient is now alive and subject to an outstanding follow-up.

An Extremely Rare and Demanding Diagnosis of Primary Renal Synovial Sarcoma: A Case Report

Primary renal synovial sarcoma (PRSS) is an extremely rare malignancy. The diagnosis of PRSS is unforeseen due to the absence of clinical and radiological typical aspects. Here, we present a case of a 69-year-old male with complaints of hematuria and left lumbar pain. Abdominal-pelvic computed tomography scan with contrast injection showed a solid mass of 8cm diameter in the left kidney and renal vein tumor thrombus. The patient was further subjected to robotic-assisted left radical nephrectomy and renal vein thrombectomy. We concomitantly performed left adrenalectomy and paraaortic lymphadenectomy. Immunohistochemical and genetic analysis revealed PRSS. This entity is characterized by abnormal chromosomal translocation t(X;18)(p11.2; q11.2) and consequently the characteristic SYT-SSX fusion gene. Due to the disease's rarity and severity, diagnosis and management of PRSS rely upon a demanding and multidisciplinary approach.

Primary Synovial Sarcoma of the Kidney: Diagnostic Approach and Therapeutic Modalities for a Rare Nosological Entity

Synovial sarcoma (SS) is a rare mesenchymal entity that represents 5–10% among soft tissue sarcomas (STS). Primary renal synovial sarcoma (PRSS) is an uncommon, rapidly growing tumor, with potential metastatic dissemination. The main prognostic factors of PRSS include tumor size and histologic grade, while translocation t (X; 18) (p11.2; q11.2) (fusion of SYT gene -chromosome 18- with SSX genes (1, 2 or 4)-chromosome X) is the most common pathognomonic sign. Aggressive surgical resection of the tumor along with concomitant regional lymphadenectomy is the treatment of choice for PRSS, while additional en bloc resection of the adjacent affected organs is often performed. To date, the role of preoperative or postoperative chemotherapy remains equivocal. The prognosis of patients with PRSS is poor, as the 5-year survival rate is only 20–30% and further deteriorates when a high mitotic activity is detected. Local recurrence even after complete R0 surgical excision remains the most frequent cause of death. The aim of this review was to meticulously discuss clinical features, histogenesis, and morphological and immunochemical findings of PRSS, while the role of current diagnostic and therapeutic management of this aggressive neoplasm was emphasized.

Primary Renal Synovial Sarcomas: PAX 8 Immunostaining and Unusual Molecular Findings

Synovial sarcoma (SS) is a high-grade sarcoma that rarely involves the kidney. Eleven renal SS cases were collected in our institution. Immunostaining features and molecular changes of renal SS were further elucidated in this study. PAX 8 was focally positive in 1 monophasic SS and diffusely positive in both the spindled and epithelial components in 1 biphasic SS. These 2 PAX8 expressing renal SS were confirmed by the presence of the classic t(X;18) translocation. Our study also revealed the presence of extra copies of the SS18 in one biphasic SS and one poorly differentiated SS. The SS18 (SYT) gene rearrangement is useful for confirming the SS diagnosis. However, a negative test (FISH or RT-PCR) does not rule out the diagnosis. Although not as common, other chromosomal alterations, such as polysomy 18, indeed occur in renal synovial sarcoma.

Primary Renal Synovial Sarcoma and Clinical and Pathological Findings: a Systematic Review

PURPOSE OF REVIEW

To update epidemiological, diagnostic, and therapeutic information on primary synovial sarcoma of the kidney.

RECENT FINDINGS

A total of 96 studies were analyzed; age at presentation was 38.6±14.2 years, predominant location of tumor was right kidney; frequent reported symptoms at diagnosis were hematuria and pain. For definitive diagnosis, cytogenetic technique was used. Detected oncogene was available in 37.8% cases with fusion of SS18-SSX in most patients. Surgery is treatment of choice, with adjuvant chemotherapy; most frequently ifosfamide-based associated with doxorubicin or epirubicin. Overall median survival was 34 months. Mortality was 29% of the cases which reported death and the recurrence rate was 39.8%. Risk of death was increased in patients with metastases at diagnosis Primary RSS occurs more often in young men. RSS often presents with symptoms and in an advanced stage. Surgical treatment is the most commonly used and chemotherapy for advanced or recurrent treatment.

Desmoplastic Small Round Cell Tumor of the Kidney: Report of a Case, Literature Review, and Comprehensive Discussion of the Distinctive Morphologic, Immunohistochemical, and Molecular Features in the Differential Diagnosis of Small Round Cell Tumors Affecting the Kidney

Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive neoplasm typically presenting with widespread involvement of the abdominopelvic peritoneum of adolescent males, usually without organ-based primary. Although it is believed to originate from the serous (mainly peritoneal) membranes, intracranial, sinonasal, intraosseous, and other soft tissue sites are also documented. A chromosomal translocation t(11:22)(p13;q12) signature that fuses EWSR1 and WT1 genes results in the production of a chimeric protein with transcriptional regulatory activity that drives oncogenesis. Integration of clinical, morphologic, immunohistochemical, and genetic data is necessary to arrive at the correct diagnosis, especially when the tumor arises in an atypical site. A 15-year-old male presented with hematuria and was found to have a large renal tumor associated with adrenal, liver, lung, and bone metastases. Histopathologic and immunophenotypic features were distinctive for DSRCT. This diagnosis was confirmed by means of fluorescence in situ hybridization and cytogenetic analysis, which documented the pathognomonic t(11;22) translocation, and by reverse transcription polymerase chain reaction on snap-frozen tissue, which revealed the EWSR1/WT1-specific chimeric transcript. Despite high-dose chemotherapy and radiation therapy targeted to a single T11 vertebral metastasis, the disease progressed, and the patient died 4 years after the diagnosis. A search of electronic databases for DSRCT yielded 16 cases of well-documented renal primaries out of around 1570 cases from all sites gathered from the global literature. Desmoplastic small round blue cell tumor and other primary renal tumors considered in the differential diagnosis with DSRCT are discussed.

Incidence, treatment, and outcomes of primary and recurrent Non-Wilms renal tumors in children: Report of 109 patients treated at a single institution

INTRODUCTION

Non-Wilms renal tumors represent a compelling subset of childhood renal tumors. However, their relative rarity renders accurate diagnosis, and therapy challenging which in some instance is inferred from their adult counterparts.

OBJECTIVE

To describe the incidence and analyze the diagnostic challenges, therapies and, outcomes of non-Wilms renal tumors at the largest tertiary cancer centre in India.

METHODS

All patients with histologically confirmed non-Wilms renal tumours diagnosed in the paediatric oncology unit of Tata Memorial Hospital between 2006 and 2019 were included. Data regarding clinical and radiological features and treatment outcomes were retrieved from the prospectively maintained institutional database. At the outset, histological types were categorised into a high and low-risk group depending on anticipated survival. Survival analysis was performed utilising the Kaplan-Meier method on SPSS software version 24.0.

RESULTS

Of the 569 patients with renal tumors, 109 (19%) patients with primary (n = 97) or recurrent (n = 12) non-Wilms renal tumors were included. Histological high-risk group included clear cell sarcoma (CCSK) (39.4%), renal cell carcinoma (RCC) (19.3%), malignant rhabdoid tumor (MRTK) (12.8%), Ewing's sarcoma (rES) (15.6%), synovial sarcoma (2%), and undifferentiated sarcoma (2%). The low-risk group comprised of congenital mesoblastic nephroma (CMN) (4.6%), cystic partially differentiated nephroblastoma (2%), and other rare tumors (3%). Diagnostic error occurred in 2 patients in the high-risk group. All low-risk tumours were treated with surgery alone and most (97%) high-risk tumors were operated either upfront (61.5%) or after preoperative chemotherapy (38.4%). Adjuvant therapy based on histology was offered to 70%. The recurrent tumors received various salvage treatments including chemotherapy; radiotherapy; surgery and immunotherapy, however, only 2 patients could be salvaged. The 3-year overall survival for the entire cohort with primary tumors was 59%, and the survival rates were 76.7%, 77.9%, 0.0%, and 52% for CCSK, RCC, MRTK, and rES (summary figure). Low-risk tumors had 100% survival while the recurrent tumors had a median survival of 10.5 months.

CONCLUSIONS

Non-Wilms renal tumors constitute a heterogeneous group of tumors, accounting for less than 20% of all renal tumors. Low-risk tumors are associated with excellent outcomes following surgery alone while the high-risk tumours have a variable outcome. MRTK and recurrent non-Wilms tumour have the worst survival. Favourable outcomes for CCSK and RCC and worst outcomes for MRTK were observed in this study. Renal ES have higher incidence of treatment failure and unsatisfactory outcomes. Recurrent non-Wilms tumours have an extremely poor outcome and more alternative or innovative approaches are needed for their treatment.

Primary Intraosseous Synovial Sarcoma with Molecular Confirmation: Expanding and Clarifying the Spectrum of This Rare Neoplasm

Synovial sarcoma is a well-known malignant tumor usually originating within deep soft tissues of the lower extremities of adolescents and young adults. Rare radiologically confirmed examples of primary bone synovial sarcoma have been documented, generally in isolated case reports. Herein, we report two cases of primary intraosseous synovial sarcoma, with molecular confirmation, involving the left humerus of a 45-year-old female and the right fourth metatarsal bone in a 36-year-old male. Additionally, we clarify the spectrum of primary intraosseous synovial sarcoma by separately analyzing reported cases with radiographic confirmation of bone origin and molecular support for the diagnosis. There are clinicopathologic differences between those tumors with documented molecular confirmation and those lacking such confirmation, specifically regarding their anatomic distribution (p < 0.0001). Regarding the radiology of our two cases, the humeral lesion appeared almost entirely intramedullary without soft tissue extension; the midfoot lesion demonstrated a destructive, metatarsal-centered bone lesion, initially thought clinically to represent primary bone osteosarcoma. The diagnoses of monophasic synovial sarcoma were rendered via core needle biopsies, with molecular FISH confirmation of SYT gene rearrangement. Clinical follow-up data was only available for the female patient with the primary humeral lesion, who underwent surgical resection, with no local recurrence or distant metastasis at 7 months postsurgery. To our knowledge, these are the first reported examples of molecularly confirmed, primary intraosseous synovial sarcomas of the humerus and metatarsal bones. Primary intraosseous synovial sarcomas with molecular confirmation differ clinically from those lacking it; however, the demographic features and metastatic potential appear similar to primary soft tissue synovial sarcoma.

Primary renal synovial sarcoma: A case report

BACKGROUND

Synovial sarcoma, a rare mesenchymal tumor type with unclear histological origin and direction of differentiation, accounts for 6%–10% of soft tissue tumors. It is mainly located near the joints and tendons of the limbs, and occurs primarily in children or young adults. Primary renal synovial sarcoma (PRSS) is very rare, accounting for approximately 1% of synovial sarcomas. It is a spindle cell tumor type affecting mesenchymal tissue, and has morphological, genetic, and clinical characteristics, and a certain degree of epithelial differentiation. It is highly malignant and has the fourth highest incidence among soft tissue sarcomas. Here, we report a case of PRSS and share some valuable information about the disease.

CASE SUMMARY

A 54-year-old male patient was admitted to the hospital for a space-occupying lesion in the right kidney for 2 d upon ultrasound examination. The patient had no cold or fever; no frequency, urgency or pain of urination; and no other discomfort. The results of a hemogram, blood biochemistry, and tumor markers were in the normal range. The patient was examined by computed tomography (CT), which indicated the presence of a soft tissue density shadow with a diameter of approximately 6.8 cm in the right renal pelvis area, showing uneven enhancement. Ultrasound indicated a cystic solid mass of approximately 6.8 cm × 6.5 cm in the right kidney, with an unclear boundary and irregular shape. Meanwhile, color Doppler flow imaging showed dotted blood flow signals in the periphery and interior. Contrast-enhanced ultrasound (CEUS) showed "slow in and fast out" hyperenhancement of the right renal mass after contrast agent injection. The postoperative pathological diagnosis was (right kidney) synovial sarcoma. Despite postoperative adjuvant chemotherapy, tumor recurrence was detected two years later.

CONCLUSION

PRSS is a rare malignant tumor. To date, no characteristic imaging findings have been observed. The diagnosis is confirmed primarily through postoperative pathological immunohistochemistry and SS18 (SYT) gene detection. In this case, CEUS was used preoperatively. We found that PRSS has the characteristic of "slow in and fast out" hyperenhancement, and its particular characteristics have diagnostic value. Postoperative adjuvant chemotherapy is not very effective.

Primary synovial sarcoma of the kidney: a case report of complete pathological response at a Lebanese tertiary care center

Background

Primary synovial sarcoma of the kidney is a rare type of soft tissue sarcoma. Its presenting features can resemble those of other renal tumors; rendering its early diagnosis, a dilemma. Several cases of renal synovial sarcoma have been reported in the literature with varying treatment options and outcomes. This article describes a rare case of primary renal synovial sarcoma and reviews all cases in the literature.

Case presentation

A 26-year-old male presented with flank pain and hematuria. Initially diagnosed with Wilm’s tumor, revision of pathology and histology, along with the immunohistochemical profile, confirmed, nevertheless, the diagnosis of primary monophasic synovial sarcoma of the kidney with the SYT-SSX2 fusion transcript. Follow-up, post nephrectomy, revealed recurrence within the lungs and at the surgical bed. Surgical resection followed by adjuvant chemotherapy regimen constituting of Doxorubicin and Ifosfamide, achieved complete pathological response.

Conclusion

In this case report, we emphasize the need for accurate diagnosis and prompt treatment. We propose multimodality treatment approach including surgery along with anthracycline-based chemotherapy to induce complete remission.

Adult Wilms tumor with inferior vena cava thrombus and distal deep vein thrombosis - a case report and literature review

BACKGROUND

Adult Wilms tumor (WT, nephroblastoma) is a rare, but well-described renal neoplasm. Although inferior vena cava tumor thrombosis is present in up to 10% of Wilms tumors in childhood, only few cases of this clinical manifestation in adults have been reported. To the best of our knowledge, this is the first case of adult WT infiltrating into inferior vena cava (IVC) with concomitant distal deep vein thrombosis.

CASE PRESENTATION

A 28-year-old male patient with gross hematuria and right flank pain was diagnosed with right kidney tumor penetrating to IVC. Preoperatively, acute distal thrombosis in inferior vena cava and lower extremities veins occurred. Right radical nephrectomy with tumor thrombectomy via cavotomy was performed. In order to prevent pulmonary embolism, IVC was ligated below left renal vein level. Histopathological examination revealed a triphasic nephroblastoma without anaplastic features. Postoperatively, patient was diagnosed with metastatic liver disease, which was treated with two lines of chemotherapy followed by radiotherapy with achievement of complete response.

CONCLUSIONS

Adult WT occurs usually in young patients, under 40 years of age. Neoadjuvant chemotherapy proved to be effective in children, resulting with tumor shrinkage and venous tumor thrombus regression. Therefore, percutaneous biopsy should be always considered in young patients presenting with renal tumor invading venous system. IVC ligation is a safe treatment option in the event of complete inferior vena cava occlusion due to distal thrombosis concomitant to tumor thrombus, provided collateral venous pathways are well-developed.

Biphasic renal synovial sarcoma with extensive venous tumor thrombosis: A rare presentation

Primary renal synovial sarcoma (SS) is a very rare soft-tissue tumor arising from the kidney. These tumors histologically closely resemble other sarcoma variants. Immunohistochemical and cytogenetic techniques remain the cornerstone in achieving the correct diagnosis. Radical surgical excision is the primary treatment for local tumor control and alleviation of symptoms. Adjuvant chemotherapy, at present, has only a limited role. We report a unique case of a 21-year-old young male with the diagnosis of a biphasic renal SS with extensive venous system thrombosis involving the inferior vena cava, bilateral iliac, and femoral vessels which was managed by radical nephrectomy and tumor thrombectomy followed by adjuvant chemotherapy.

Renal Synovial Sarcoma in a Young Pregnant Lady: A Case Report and Clinico-Pathological Profile

Synovial sarcoma is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features. These tumours usually arise in the extremities of young adults. Their occurrence in the kidney is extremely rare. A 25-year-old pregnant lady in her first trimester was incidentally found to have a left renal mass on perinatal ultrasonography. MRI showed a well encapsulated, heterointense mass replacing the left kidney. Following medical termination of her pregnancy, a radical nephrectomy was performed. Histopathology revealed a primary synovial cell sarcoma of the kidney. Postoperatively, she received ifosfamide based adjuvant chemotherapy. This report highlights the challenges involved in the diagnosis of this extremely rare neoplasm. A high index of clinical suspicion, complimented by the use of immunohistochemistry and cytogenetics during histopathological analysis aide in the diagnosis. Aggressive management with a combination of complete surgical extirpation and chemotherapy gives the best results.

Primary synovial sarcoma of the kidney: A case report

Synovial sarcoma (SS) is a soft-tissue tumor with a unique t(X;18)(p11.2;q11.2) chromosomal translocation that can be identified by polymerase chain reaction in tissue homogenates. Generally, the tumor occurs in the proximity of the joints. The current study presents the case of a 54-year-old female with primary SS (PSS) of the right kidney; this is an extremely rare tumor accounting for <2% of malignant renal carcinomas. The patient presented with an interrupted right flank pain of 20 years duration, with a precipitating factor of a hematuria of 8 days. Abdominal computerized tomography (CT) scan revealed a heterogeneous, unclear-marginated soft tissue arising in the upper pole of the right kidney with solid, necrotic components and heterogeneous enhancement. Renal cell carcinoma was diagnosed pre-operatively. A right nephrectomy was performed, and the patient is currently free of metastasis 12 months after the surgery. The current treatment for renal SS includes surgical resection and ifosfamide-based chemotherapy. To the best of our knowledge, <50 cases have been reported in the English literature. Urologists should be aware of the possibility of malignancy in cystic renal masses and consider a diagnosis of SS. Along with the case report, the current study presents a literature review on the diagnosis and treatment of PSS.

Primary renal synovial sarcoma: computed tomography imaging findings

BACKGROUND

A synovial sarcoma arising from the kidney is extremely rare. To date, few data are available on their radiological features.

PURPOSE

To identify the computer tomography (CT) imaging findings of primary renal synovial sarcomas (PRSSs).

MATERIAL AND METHODS

Five cases of PRSS confirmed by histopathological and cytogenetic studies were retrospectively analyzed. All patients had undergone unenhanced and multiphase enhanced CT examinations (one patient underwent CT twice). The CT characteristics, including shape, size, margin, attenuation, and enhancement pattern after intravenous contrast medium injection, were analyzed.

RESULTS

The study involved two female and three male patients (mean age, 27.4 years; range, 15-43 years). Unenhanced CT showed completely or partly well-defined masses, with heterogeneous (n = 5) or homogeneous (n = 1) patchy low density. On multiphase contrast-enhanced CT, in five of the six CT examinations, the tumors appeared as solid-cystic masses with cyst walls or pseudo-capsules, and demonstrated moderately heterogeneous (n = 5) and/or septate enhancement (n = 2), with a "rapid wash-in and slow wash-out" pattern of enhancement in the solid component. Only one tumor showed a simple cyst appearance and developed an irregular, intratumoral, septate soft density 8 months later. A renal vein and inferior vena cava thrombus was noticed in one patient, while lymphadenopathy was not observed in any patient.

CONCLUSION

PRSS should be included in the differential diagnosis when an adolescent or young adult presents with a renal neoplasm appearing as a solid-cystic mass with well-defined borders, a cystic wall or pseudo-capsule, heterogeneous or septate enhancement, a "rapid wash-in and slow wash-out" pattern of enhancement in the solid component, and no sign of lymphadenopathy.

Soft tissue sarcomas of the kidney

Soft tissue sarcomas are rare mesenchymal tumors. Amongst others, primitive neuroectodermal tumors (PNET) of the kidney and synovial sarcoma of the kidney belong to the group of soft tissue sarcomas. Synovial sarcomas can occur almost anywhere in the body, most frequently, however, in the lower (62%) or upper extremities (21%). Metastases occur in 50-70% of cases, and thus the prognosis is poor. PNETs are rare, highly aggressive neoplastic lesions which mainly occur in the torso or axial skeleton in young adults. The prognosis is poor with a 5-year disease-free survival rate of 45-55%. The primary therapeutic approach is surgical resection. Most randomized studies assessing adjuvant chemotherapy for all types of localized soft tissue sarcomas did not show statistically significantly better overall survival times after chemotherapy, although they did show longer progression-free survival. We report on two cases of primary renal synovial sarcoma and one case of PNET of the kidney.

Histologic variability and diverse oncologic outcomes of prostate sarcomas

Purpose

Primary prostate sarcomas are a rare type of prostate cancer that account for less than 0.1% of primary prostate malignancies. We analyzed the experience of a single institution with prostate sarcoma over 20 years.

Materials and Methods

In this case series, the medical records of 20 patients with prostate sarcoma were reviewed from June 1990 to December 2013 to identify symptoms at presentation, diagnostic procedures, metastasis presence and development, histologic subtype, French Fédération Nationale des Centres de Lutte Contre le Cancer grade, primary tumor grade and size, and treatment sequence, including surgery and preoperative and postoperative therapies. The average follow-up period was 23.6 months (range, 1.4-83.3 months).

Results

The average patient age was 46.3±16.7 years. Most patients presented with lower urinary tract symptoms (55%). The histologic subtype was spindle cell sarcoma in five patients (25%), rhabdomyosarcoma in three patients (15%), synovial sarcoma in three patients (15%), liposarcoma in three patients (15%), stromal sarcoma in three patients (15%), and Ewing sarcoma, nerve sheath tumor, and adenocarcinoma with sarcomatoid component (5% each). For liposarcoma, two patients were alive after complete surgical resection and had a good prognosis. At last follow-up, 15 patients had died of sarcoma. The 2- and 5-year actuarial survival rates for all 20 patients were 53% and 12%, respectively (medial survival, 20 months).

Conclusions

The disease-specific survival rate of prostate sarcoma is poor. However, sarcoma that is detected early shows a better result with proper management including surgical intervention with radio-chemotherapy than with no treatment. Early diagnosis and complete surgical resection offer patients the best curative chance.

Clinical and pathological features of primary renal angiosarcoma

INTRODUCTION

We review all cases of renal angiosarcoma described in the medical literature to describe its clinical and histological features.

METHODS

The search term was "angiosarcoma of the kidney." All articles or case reports in English, French, German or Spanish published until March 15, 2013 were considered. When available, data that focused on clinical and pathological features were extracted.

RESULTS

In total, the final cohort included 42 cases. The median overall survival (OS) was 5.0 months (95% confidence interval [CI], 2.1-7.9). Patients with metastatic disease had more than a threefold increase in the risk of death compared to patients without meta-static disease (hazard ratio: 3.27, 95% CI, 1.48-7.24; p = 0.004). Non-metastatic patients had dismal disease-free survival (DFS) rates, with a median DFS of 6.0 months (95% CI, 4.3-7.7); despite this, chemotherapy was effective to increase survival in eligible patients (4.0 vs. 1.0 months; p = 0.001). Microscopic examination found epithelioid and spindled cell in 44% and 56% of cases, respectively; there was a statistically insignificant increase in survival in patients with epithelioid patterns compared to spindled ones (9.0 vs. 4.0 months; p = 0.077). The tumour grading was related to OS; the lower the grade, the longer the survival (13 vs. 4 months; p = 0.029).

CONCLUSIONS

Renal angiosarcoma is a rare disease with defined clinical and pathological features. It has a very poor prognosis in patients with metastatic disease and a high recurrence rate in patients with non-metastatic disease.

CT findings of synovial sarcomas of the kidney with pathological correlation

PURPOSE

To describe computed tomography (CT) findings of primary synovial sarcoma of the kidney with pathological correlation.

METHODS

CT findings of four cases of pathologically confirmed synovial sarcoma of the kidney were retrospectively viewed and correlated with pathologic features.

RESULTS

The four synovial sarcomas presented as soft tissue masses with multiple smooth wall cysts. Pathologically, entrapped and dilated renal tubules formed the smooth wall cysts lined by hobnail tubular epithelium.

CONCLUSION

Primary renal synovial sarcoma might manifest as a renal mass with multiple smooth wall cysts. The cysts are consistent with entrapped dilated renal tubular and are lined with hobnail tubular epithelium.

Primary monophasic synovial sarcoma of the liver in a 13-year-old boy

Synovial sarcoma originating in the liver is extremely rare, and thus far only 3 cases have been reported in the English literature. Herein, we report a primary hepatic synovial sarcoma in a 13-year-old Chinese boy. This patient present with a 10-day right upper quadrant pain, and a heterogeneous mass was documented in the right hepatic lobe by computed tomography. Subsequently, the patient underwent right hepatectomy. Histologically, the tumor exhibited classic features of monophasic synovial sarcoma. The diagnosis was confirmed by the presence of SS18 gene rearrangement and identification of SS18-SSX1 fusion transcript. Unfortunately, a relapsing mass was detected 11 months after the surgery. To the best of our knowledge, the current case is the 1st published example in the pediatric population.

Primary renal carcinoid tumor: A rare cystic renal neoplasm

We present the case of a 21-year-old man with an incidentally detected cystic renal mass. A well-defined, solid mass measuring approximately 8 cm x 6 cm with a cystic component was identified in the left kidney by abdominal multidetector computed tomography (CT) and ultrasonography. The mass was well-enhanced on the corticomedullary CT phase and washout of enhancement occurred on the nephrographic phase. The mass contained peripheral wall and septal calcifications in the cystic component. The lesion was resected and diagnosed as a primary renal carcinoid tumor. Primary carcinoid tumors of the kidney are extremely rare. This case is notable because of the rarity of this neoplasm and its unique radiologic and pathologic findings. A review of previously reported cases in the literature is also presented.

Pulmonary Embolism in a Patient with Primary Renal Synovial Sarcoma: The Important Differential Diagnosis of Tumor Embolism and Its Therapeutic Implications

Pulmonary tumor embolism rarely occurs in epithelial-derived tumors, but it has been described in different tumor entities. Microscopic pulmonary tumor embolisms are often only discovered on autopsy. Pulmonary thromboembolism, on the other hand, is a frequent complication in cancer patients, and surgery in patients with a malignant tumor is an additional risk factor. The differential diagnosis between pulmonary thromboembolism and pulmonary tumor embolism can be challenging. In this case report, we describe the rare case of a patient with primary renal synovial sarcoma and the workup for a thrombus in the left pulmonary artery.

Clinical and pathological features of primary neuroectodermal tumor/Ewing sarcoma of the kidney

OBJECTIVE

To collect and analyze clinical and pathological features of primitive neuroectodermal tumor (PNET)/Ewing sarcoma (EWS), a rare tumor occurring most commonly in bone and soft tissues of young people, which rarely occurs as a primary renal neoplasm and exhibits highly aggressive biological behavior.

METHODS

All cases of PNET/EWS published from 1975 to February 2012 were collected. When available, clinical and pathological data were extracted for each case. Survivals were estimated with the Kaplan-Meier method and compared with the log-rank test with 95% confidence interval (CI).

RESULTS

A total of 116 cases were found. All patients had clinical symptoms as first presentation of disease such as pain (54%), hematuria (29%), and bulky renal mass (28%). Sixty-six percent of patients had stage IV disease at diagnosis. Median disease-free survival (DFS) was 5.0 months (95% CI 2.4-7.6). The probability to be alive at 18 months was 60% and 85% for patients with metastatic disease (M1) or not (M0) at diagnosis, respectively. Median overall survival (OS) was 24 months (95% CI 4.5-15.1) in patients with M1 disease, whereas it was not reached in patients with M0 disease (P <.001). In patients with M0 disease, 50% received neoadjuvant chemotherapy and the 12-month OS was 93% compared to 75% of untreated patients (P = .092). In patients with M1 disease who underwent treatment, the median progression-free survival (PFS) was 22.0 months (95% CI 17.9-26.1) with a clinical benefit in 74% of cases.

CONCLUSION

Our findings suggest that PNET/EWS is a rare aggressive tumor affecting principally young people, with a poor prognosis for patients with M1 disease; chemotherapy is an effective strategy in M1 disease and probably also in M0 disease.

Twenty-five cases of adult prostate sarcoma treated at a high-volume institution from 1989 to 2009

OBJECTIVE

To analyze the clinical characteristics, treatment modalities, and outcomes of adult prostate sarcoma treated at our institution.

MATERIALS AND METHODS

The medical records of 25 adult patients with prostate sarcoma were obtained from January 1989 to December 2009. The clinicopathologic parameters were evaluated to determine their effect on survival.

RESULTS

The median age was 37 years (range 18-81). The median tumor size was 9.5 cm (range 4-25). The median serum prostate-specific antigen level was 1.39 ng/mL (range 0.39-33.20). The most common symptom was dysuria (72%). Transrectal ultrasound-guided needle biopsy was used to diagnose 22 sarcomas, transurethral resection of the prostate to diagnose 2, and open surgery to diagnose 1. The predominant histologic subtype was leiomyosarcoma (40%); 21 (88%) were high grade and 6 patients had metastatic disease. Surgical resection of curative intent was performed in 14 patients, with negative margins in 10. After a median follow-up of 21 months (range 5-63), 2 patients were disease free, 4 were alive with disease, and 19 had died of their disease. Overall, the 1-, 2-, 3-, and 5-year survival rate was 80.0%, 47.4%, 22.6%, and 11.3%, respectively, and the median survival time was 23 months. The median survival time after recurrence was 20 months (range 9-39) and that after metastasis was 10 months (range 3-23). Age >50 years, metastasis at presentation, and a lack of surgery with curative intent were independently predictive of an unfavorable outcome.

CONCLUSION

Adult prostate sarcoma accounted for 0.7% of primary prostate malignancies and carried a poor prognosis. Early diagnosis and surgical resection with curative intent offer patients the best chance of survival.