Differential cyclin-E1 expression in CIC-rearranged sarcoma.

CIC-rearranged sarcoma (CRS) is a group of high-grade undifferentiated small round cell sarcomas examined as a separate entity in the current WHO classification; since it shows more aggressive clinical behavior and distinct morphological and molecular features compared to Ewing sarcoma (ES). As CCNE1 expression is associated with tumor growth in CIC::DUX4 sarcomas, we aimed to demonstrate the value of cyclin E1 expression in CRS. Cyclin E1 immunohistochemistry and break-apart FISH for EWSR1 and CIC gene rearrangements were performed on 3-mm tissue microarrays composed of 40 small round cell tumors. Five cases were classified as CRS, whereas 22 were ES and 13 were unclassified (EWSR1-/CIC-). Among all three diagnostic groups, we found cyclin E1 expression level to be higher in CRS (80 %) and unclassified groups (61.5 %) compared to ES (4.5 %, p < 0.001). In addition, high cyclin E1 expression levels were associated with higher mean age at diagnosis, presence of atypical histology and myxoid stroma, low CD99 expression, and presence of metastasis at diagnosis. The sensitivity and specificity of high cyclin E1 expression in detecting non-ES cases were 95.5 % and 66.7 %, respectively. However, the correlation between cyclin E1 expression level and survival was not statistically significant. This is the first study that shows cyclin E1 immunohistochemical expression in EWSR1-negative undifferentiated small cell sarcomas, particularly CRS.

Painless Growing Swelling on the Palm of a 4-year-old Boy: Malignant Peripheral Nerve Sheath Tumor.

In this study, we present a 4-year-old male patient with a slowly growing painless mass in the palm of his left hand for 2 years. Although musculoskeletal tumors are rare, hand localized tumors are even rarer in pediatric patients. The fact that very few (less than one in ten) tumors are malignant and there are dozens of subtypes, each with different treatment management, shows the importance of the management of these lesions. Appropriate diagnosis and management of soft tissue masses, especially insidious malignant tumors, is vital. Due to the rarity of soft tissue tumors, adequate guidelines for their management are limited. The purpose of this report is to present an example of the approach to one of the soft tissue tumors.

Undifferentiated High-Grade Pleomorphic Bone Sarcoma: A Case Report.

Undifferentiated pleomorphic bone sarcoma (UPS-B) is a rare high-grade sarcoma of bone that is usually seen in advanced age. There is no specific line or pattern of differentiation, and the diagnosis is often made by exclusion. It is especially important to differentiate it from osteosarcoma and dedifferentiated chondrosarcoma. It tends to be located most frequently in the lower extremity, particularly the femur. It is treated with the osteosarcoma protocol. In this study, a case of undifferentiated high-grade pleomorphic bone sarcoma located in the distal femur was reported. It aimed to discuss the patient's clinical presentation, diagnostic approach, treatment, and follow-up process in light of the literature. In this case, the tumor was resected with wide margins after neoadjuvant chemotherapy. He died of diffuse lung metastases during the adjuvant chemotherapy process. Unlike the literature, the patient was only 29 years old. The patient died 8 months after the first diagnosis.

A challenging case of an adamantinoma of fibula with soft tissue mass harboring distinct histopathology.

We present a case of adamantinoma that originated from the fibula and had a large soft tissue component measuring approximately 6 cm. Clinical, radiological, and pathological investigations initially suggested that the tumor might be a bone-invading synovial sarcoma. To the best of our knowledge, no other case of fibular adamantinoma with such a large soft tissue component has been reported in the literature.

A rare lesion that mimics a bone tumor: Osseous hydatidosis.

OBJECTIVES: This study aims to evaluate the symptoms, skeletal manifestations, and management of patients with tumor-like osseous hydatidosis treated in our oncology clinic in the long term and to share our clinical experience with this extremely rare disease. PATIENTS AND METHODS: Between December 2010 and May 2019, a total of 11 patients (6 males, 5 females; mean age: 45.1±13 years; range, 22 to 70 years) who were treated with a bone hydatid cyst (HC) and followed were retrospectively analyzed. Epidemiological, clinical, diagnostic, and therapeutic data of the patients with long-term follow-up were collected. RESULTS: The mean follow-up was 63.2±23.9 (range, 24 to 101) months. The most common site of bone hydatidosis was the femur in four (36%) patients. The most common clinical presentation was pain in seven (63.6%) patients. Two (18.2%) patients had a pathological fracture of the femur. It was detected incidentally in two patients. Contact history was present in two patients (with dog), and two (18.2%) patients had concomitant extraosseous cystic echinococcosis in the liver. Complete blood count analysis was performed in all patients and eosinophilia was positive in three (27.3%) patients. As treatment, curettage cementation was performed in nine (81%) patients (internal fixation was also applied to five of them), while wide resection and prosthesis were applied to two (18.2%) patients. CONCLUSION: The diagnosis of osseous hydatidosis is difficult and the prognosis is often poor. This entity should be kept in mind for the differential diagnosis of the cystic or tumoral lesions of the bone.

Adamantinoma with a Prominent Spindle Cell Component Mimicking Intraosseous Synovial Sarcoma: Clinicopathological Features of Six Tumors.

Introduction. Adamantinoma is sub-classified into classic/biphasic, osteofibrous dysplasia-like, and de-differentiated type. We present six adamantinomas with a prominent spindle cell component mimicking intraosseous synovial sarcomas. Methods. Six patients were either referred with a diagnosis of intraosseous synovial sarcoma or wherein synovial sarcoma was a differential diagnosis. Three tumors were tested for SS18 gene rearrangement by FISH and two for SS18::SSX fusion by RT-PCR technique. Results. There were three males and three females with an average age of 20.6 years. Radiologically, the lesions were expansile and showed lytic and/or sclerotic components, involving the cortex and/or medulla. Five lesions occurred in the tibia and two in the fibula. Two tumors displayed soft tissue extension and two occurred as multifocal lesions. Two patients were diagnosed with synovial sarcoma and a single patient with sarcomatoid carcinoma, elsewhere. Two "in-house" patients were initially diagnosed with synovial sarcomas. On review, all tumors were cellular comprising monomorphic spindle-shaped cells arranged in sheets and fascicles (n = 6), including a "herringbone-like" pattern (n = 3), focal tubules (n = 1), cohesive nests (n = 5), cords (n = 2), including pseudocystic component (n = 2). Immunohistochemically, tumor cells were positive for p63 (6/6), p40 (4/4), EMA (2/3), AE1/AE3 (5/6), various keratins (2/2), and TLE1 (2/4). Three tumors tested for SS18 rearrangement were negative, while two tumors tested for SS18::SSX fusion were negative. Conclusions. Adamantinomas with spindle cell morphology display overlapping features with synovial sarcoma. A clinico-radiological index of suspicion immunostains (p63 and p40) and molecular test for t(X; 18) translocation are useful in an exact diagnosis, which has treatment-related implications.

Granulocytic sarcomas: difficulties in diagnosis.

Granulocytic sarcoma is an uncommon tumor composed of myeloid blasts and/or immature myeloid cells in an extramedullary site which is usually associated with acute or chronic myeloid leukemia. The tumor may also be the initial manifestation of leukemia. The histomorphological diagnosis of granulocytic sarcoma can be challenging to pathologists, especially in the absence of a known hematological disorder. In this case, differentiation of granulocytic sarcoma from malignant lymphomas and other small round cell tumors is very critical. Seven cases of granulocytic sarcoma are reported in this paper. One patient had granulocytic sarcomas at two different sites. Hematoxylin-eosin-stained sections were reexamined. Blastic, poorly differentiated, and well differentiated histopathological variants were found in two, five and one cases, respectively. Immunohistochemical studies were performed on formalin-fixed tissue from all cases using a avidin-biotin-peroxidase complex technique. The panel included antibodies against LCA, CD43, CD34, c-kit, myeloperoxidase, CD68 KP1, CD15, and CD99. All cases stained positively with LCA, CD43, CD34, myeloperoxidase, and CD68. Five cases were positive for c-kit, three cases were positive for CD15, and two cases were positive for CD99. An immunohistochemical panel including at least myeloperoxidase, CD68 and CD34 can be used for detection of myeloid differentiation. It is also important that granulocytic sarcoma be considered in the differential diagnosis of CD99-positive round cell tumors.

Giant retroperitoneal dedifferentiated liposarcoma.

INTRODUCTION: Liposarcoma is the most frequent type of retroperitoneal sarcomas. Dedifferentiated liposarcoma is the least common subtype and is an extremely rare tumor. CASE REPORT: We present the case of a 53-year-old male who was referred with a giant retroperitoneal mass. The patients' mass was deemed unresectable by the previous institution and received chemotherapy with no benefit. We macroscopically removed the 38x32 cm mass with right nefrectomy. Pathological examination revealed dedifferentiated liposarcoma. CONCLUSION: Surgery is the gold standart in the treatment of retroperitoneal sarcomas. Giant masses present a challenge for the surgeon with possible major vascular injuries and multiorgan resections. Therefore it is important for these patients to be referred for surgery without delay. KEY WORDS: Dedifferentiated liposarcoma, Liposarcoma, Retroperitoneal sarcoma.

Gastric Medullary Carcinoma: A Rare Case Report.

A case of 64-year-old female patient with early stage gastric medullary carcinoma has been presented, along with a review of the literature.

Prognostic factors for teenage and adult patients with high-grade osteosarcoma: an analysis of 240 patients.

The aim of this retrospective, multicenter study was to evaluate clinicopathological characteristics, prognostic factors and treatment outcomes of teenage and adult patients with high-grade osteosarcoma. A total of 240 osteosarcoma patients who were diagnosed and treated from March 1995 to September 2011 were analyzed. Median age was 20 years (range 13-74 years), and 153 patients (63.8%) were male. Primary tumor localization was extremity in 204 patients (85.4 %), trunk in 21 patients (8.8%) and head and neck region in 14 patients (5.9%). According to American Joint Committee on Cancer staging system, 186 patients (77.5%) were stage II, 3 (1.3%) were stage III and 48 (20.0%) were stage IV. Median overall survival (OS) was 55 months (95 % CI 36.8-73.1 months). OS after 2, 5 and 10 years were 67, 49 and 42%, respectively. Univariable analysis for OS showed that male gender (p = 0.032), high baseline lactate dehydrogenase (LDH) level (p < 0.001), high baseline serum alkaline phosphatase level (p = 0.002), telangiectatic subtype (p = 0.023), presence of metastasis at diagnosis (p < 0.001), presence of tumor positive margins after primary surgery (p = 0.015), poor pathological response to preoperative chemotherapy (p = 0.006) and presence of recurrent disease during follow-up period (p < 0.001) were significantly associated with poor survival. Patients who received postoperative methotrexate plus doxorubicin plus cisplatin (M + A + P) combination regimen (p = 0.019), underwent surgery for recurrent disease (p < 0.001) and received chemotherapy for recurrent disease (p < 0.001) had longer OS. In multivariable analysis for OS, only high LDH level (p = 0.002) and the presence of metastasis at diagnosis (p = 0.011) were associated with poor OS, whereas the patients who received chemotherapy for recurrent disease had a longer OS (p = 0.009).