Malignant Small Round Cell Tumor Research Articles

Unusual Presentation of Myeloid Sarcoma as Thigh Mass

IntroductionMyeloid sarcoma (MS) is a tumor containing myeloid blasts, with or without maturation, involving any anatomical site other than the bone marrow. It can occur de novo or following a hematological malignancy. CaseWe report a 6-year-old female who presented with fever and a rapidly enlarging left thigh mass. The initial provisional diagnosis considered was tubercular hip arthritis with an abscess, but imaging investigations suggested neoplastic swelling. A biopsy of the mass showed a malignant small-round cell tumor. Bone marrow aspiration revealed the diagnosis of acute myeloid leukemia without the presence of blasts in the peripheral smear. ConclusionMS is a rare malignancy. The diagnosis is often delayed due to a lack of clinical suspicion and the absence of blasts in peripheral blood. This report aims to enhance the awareness of pediatric nurse practitioners that MS should also be considered as a differential for an extremity mass.

Elucidating the nature of acinic cell carcinoma of the breast with high-grade morphology: evidence from case report

BackgroundAcinic cell carcinoma (AciCC) of the breast is a rare subtype of breast cancer. It was considered a low-grade triple-negative breast cancer (TNBC) with the potential to progress or transform into a high-grade lesion because of the molecular similarities with conventional aggressive TNBC in several genetic studies. Microscopically, the coexistence of classical low-grade and high-grade triple-negative components in breast AciCC is not uncommon. However, there is a scarcity of research on the comparative histopathological and genetic aspects of both components.Case presentationA 34-year-old woman with a nontender mass in the upper outer quadrant of the left breast was initially diagnosed with a malignant small round cell tumor (undifferentiated or poorly differentiated carcinoma) based on a preoperative biopsy, which was later identified as breast AciCC with a high-grade solid component. Left breast-conserving surgery with sentinel lymph node biopsy was performed. Microscopically, the breast AciCC consisted of a classical acinic component and a high-grade component. The latter demonstrated a solid sheet-like pattern characterized by large, round, pleomorphic or vesicular nuclei, prominent nucleoli, and frequent mitotic activities. Classical acinic architectures focally merged together to form solid nests and transited into high-grade areas. Remarkably, in the high-grade lesion, conventional immunochemical markers for breast AciCC, such as α1-antitrypsin (AAT), Lysozyme (LYS), Epithelial membrane antigen (EMA), S100 protein (S100), and cytokeratin (CK) were negative, whereas cell cycle protein D1 (cyclin D1) and vimentin showed diffuse expression. Next‑generation sequencing (NGS) revealed that 43.5% of variants were identical in both components. Furthermore, PAK5 mutation; copy number (CN) loss of CDH1, CHEK1, and MLH1; and CN gains of CDK6, HGF, and FOXP1 were identified in the high-grade lesion. The patient was treated with eight cycles of adjuvant chemotherapy (epirubicin combined with cyclophosphamide) and radiotherapy after surgery, and she is currently alive for 43 months with no metastases or recurrences.ConclusionsThis case demonstrates a comparative analysis of the histopathological and genetic characteristics of classical low-grade and high-grade components of AciCC within the same breast. This information may serve as a morphological and molecular basis for further investigation into the molecular mechanisms underlying high-grade lesions in breast AciCC.

A case of primary skeletal muscle lymphoma mimicking cellulitis

Primary skeletal muscle lymphoma is a rare entity. Their presentation can be easily confused with a wide variety of inflammatory conditions, neoplasia as well as infectious diseases. We came across a 65-year-old lady who presented to us with complains of pain and swelling in the right thigh, leg and foot and fever-on and off for 20 days. She was initially managed elsewhere on the line of cellulitis with incision and drainage of right leg 15 days back but there had been no clinical improvement. We took her detailed history and examined her thoroughly. Relevant blood investigations were sent. However, the clinical examination findings and history were suggestive of an infective cause, blood investigations were suggestive of an acute inflammatory pathology, whereas radiological investigations (NCCT and X-ray) and cytological investigations (FNAC) which were performed at the previous place of treatment were inconclusive. We then did a CE-MRI of the right lower limb which showed centrally necrotic, enhancing mass lesion involving peroneal muscles with multiple enlarged inguinal and popliteal lymph nodes. Based on this finding, biopsy was performed and specimen was sent for histopathological examination which revealed “malignant small round cell tumor”. Immunohistochemistry was then done and tumor cells were found to be positive for vimentin, LCA, CD20 and negative for PANCK and CD3. Based on the above findings it was diagnosed as “non-hodgkin’s lymphoma (NHL) B-cell type” of right leg. Considering the confusing clinical presentation of this entity and inconclusiveness of blood and basic radiological investigations, lesions of extremities presenting with features of cellulitis must be carefully assessed.

A case of askin’s tumor presenting as acute paraplegia

Askin tumor is an uncommon malignant neoplasm of a neuroectodermic origin that arises from the soft tissues of the thoracopulmonary wall. Defined histologically by malignant small round cell tumor and immunohistochemistry positive for CD99. The lack of clinical guides that establish a standardized management contributes to its poor prognosis and short overall survival.

Biliary hemorrhage caused by a malignant small round cell tumor in the common bile duct: A case report

Type 2 diabetes mellitus (T2DM), which is distinguished by increased glucose levels in the bloodstream, is a metabolic disease with a rapidly increasing incidence worldwide. Nevertheless, the etiology and characteristics of the mechanism of T2DM remain unclear. Recently, abundant evidence has indicated that the intestinal microbiota is crucially involved in the initiation and progression of T2DM. The gut microbiome, the largest microecosystem, engages in material and energy metabolism in the human body. In this review, we concentrated on the correlation between the gut flora and T2DM. Meanwhile, we summarized the pathogenesis involving the intestinal flora in T2DM, as well as therapeutic approaches aimed at modulating the gut microbiota for the management of T2DM. Through the analysis presented here, we draw attention to further exploration of these research directions.

Malignant Small Round Cell Tumor: A Rare Aggressive Malignancy-Case Report

Background: Malignant Small round Cell Tumor (MSRCT) is very rare group of tumors. Malignant cells have similar histologic appearance making it difficult to distinguish one from another, and poses a diagnostic challenge with needs for a multimodal approach. Immunohistochemistry and immunophenotyping by flow cytometry, reverse transcriptase polymer chain reaction (RT-PCR) and fluorescence in situ hybridization are needed to confirm. The appropriate and best treatment in early stages of MSRCT is early surgical excision with chemoradiotherapy based on patient specification. Inspite of all these, tumors have poor prognosis and chance of recurrence are high. Method: Case study of a 27-year-old male who presented with a non-productive cough for 4 weeks, with feverish feeling with weight loss and shortness of breath and a new onset precordial chest pain non radiating and worse on exertion. On examination his vitals were: BP 121/91 mm of hg, pulse rate 114bpm, temperature 36.3 degrees Celsius, respiratory rate 24/per min, SPO2 96%.On examination, Elevated Jugular Venous Pressure, hyperactive precordium, displaced apex beat to 6th intercostal space anterior axillary line, muffled heart sounds and bilateral lower limb edema. Respiratory exam was unremarkable. Sputum gene expert was negative for mycobacterium tuberculosis and covid 19 rapid test was negative. Chest X Ray showed cardiomegaly and a transthoracic echocardiography revealed moderate-large pericardial effusion, with mild collapse of right atrium in diastole. Pericardiocentesis done showed hemorrhagic effusion with lymphocytes cell component, patient was initiated on treatment for TB pericarditis empirically. Three months later a chest CT scan done revealed extensive mediastinal/pericardial mass with lung nodules. An ultrasound guided mediastinal/Pericardial biopsy was done, revealed a poorly differentiated small round cell carcinoma. Results: Patient expired 14 weeks from the initial onset of symptoms while awaiting immunohistochemistry studies for specific diagnosis of the tumor and oncology review. Discussion: This demonstrates the complexity of establishing differential diagnosis of MSRCT in a resource limited setting with subsequent delay in treatment initiation, heralds poor prognosis. This also confirms difficulties in establishing differential diagnosis in poorly differentiated tumor.

Unmasking the great imitators-noninfectious conditions masquerading as spinal tuberculosis in a developing country: A single-center case series analysis

The diagnosis of spinal tuberculosis often relies on clinical, radiological, and laboratory findings, particularly in resource-constrained settings. However, numerous noninfectious conditions exhibit similar clinical and radiological features to spinal tuberculosis, leading to potential misdiagnosis in the absence of microbiological or histopathological confirmation. This study aims to present a case series from a developing country, highlighting noninfectious conditions that mimic spinal tuberculosis. A retrospective analysis was conducted on hospital records and imaging of patients diagnosed with spinal tuberculosis, lacking microbiological or histopathological evidence, and unresponsive to empirical antitubercular treatment. Patients displaying noninfectious conditions resembling spinal tuberculosis upon further investigation were included. Clinical and radiological findings of these patients were thoroughly analyzed. Among a total of 23 patients observed over a 6-year period (2015-2020), various noninfectious conditions were identified as mimickers of spinal tuberculosis. These conditions included vertebral body haemangioma, ankylosing spondylitis (with or without Andersson lesion), rheumatoid pannus, osteoid osteoma, cystic hygroma, multiple myeloma, vertebral metastasis, malignant small round-cell tumor, pancreatic pseudocyst, esophageal duplication cyst, Modic changes in degenerative disc disease, Paget's disease, and psoas hematoma. Noninfectious spinal conditions can masquerade as spinal tuberculosis, underscoring the importance of obtaining a definitive tissue diagnosis before initiating antitubercular treatment. Particular attention should be given to features such as central lesions and the absence of soft tissue involvement in suspected cases of spinal tuberculosis, warranting a careful reconsideration of the diagnosis.

A stepwise approach to fine needle aspiration cytology of lymph nodes.

The cytological diagnosis of lymph node lesions is extremely challenging because of the diverse diseases that cause lymph node enlargement, including both benign and malignant or metastatic lymphoid lesions. Furthermore, the cytological findings of different lesions often resemble one another. A stepwise diagnostic approach is essential for a comprehensive diagnosis that combines: clinical findings, including age, sex, site, multiplicity, and ultrasonography findings; low-power reactive, metastatic, and lymphoma patterns; high-power population patterns, including two populations of continuous range, small monotonous pattern and large monotonous pattern; and disease-specific diagnostic clues including granulomas and lymphoglandular granules. It is also important to remember the histological features of each diagnostic category that are common in lymph node cytology and to compare them with cytological findings. It is also essential to identify a few categories of diagnostic pitfalls that often resemble lymphomas and easily lead to misdiagnosis, particularly in malignant small round cell tumors, poorly differentiated squamous cell carcinomas, and nasopharyngeal undifferentiated carcinoma. Herein, we review a stepwise approach for fine needle aspiration cytology of lymphoid diseases and suggest a diagnostic algorithm that uses this approach and the Sydney classification system.

Diagnostic Utility of GATA3 and ISL1 in Differentiating Neuroblastoma From Other Pediatric Malignant Small Round Blue Cell Tumors.

GATA3 and ISL1 may be valuable in the diagnostic work-up of neuroblastoma and may reliably be used to support the neuroblastic lineage of pediatric small round blue cell tumors. Furthermore, dual positivity helps in challenging scenarios, when there is equivocal imaging, overlapping IHC features, limited specimen, and the lack of facility for a molecular work up.

Renal Primitive Neuroectodermal Tumor or Renal Ewing Sarcoma

Renal primitive neuroectodermal tumor (renal PNET) or renal Ewing sarcoma (renal ES) is a rare, rapidly growing malignant small round cell tumor with poor prognosis. A 32-years-old Bangladeshi male patient presented with right loin pain, fever and anemia. On CT imaging a large (18x10.5x10.0 cm) renal mass was discovered. On suspicion of malignancy, a biopsy was taken from the mass. Microscopic evaluation showed features consistent with malignant small round blue cell tumor. Immunohistochemical stains showed diffuse and strong positive reaction to CD-99 and negative for WT-1, CD-3 and CD-20, which confirmed the diagnosis of renal PNET. After 6 cycles of combined chemotherapy, the patient was relatively well and at 6 months follow-up he showed no evidence of metastasis or recurrence.
 KYAMC Journal Vol. 13, No. 04, January 2023: 257-260

A Rare Occurrence of Ewing’s Sarcoma Presenting as Breast Mass: A Case Report and Literature Review

Ewing’s sarcoma (EWS) typically involves the bony structures in adolescents and young adults. Extraskeletal sarcoma is a rare, aggressive, and malignant soft-tissue tumor with high recurrence rate. EWS of the breast is a rare entity with <1% cases reported in literature. A 55-year-old lady who complained of the gradual onset painless breast lump lasting for 1 year was referred to our institute in August 2021. Diagnostic ultrasound of bilateral breast identified a cystic lesion measuring 1.8 × 1.5 cm in lower inner quadrant of right breast. Diagnostic excisional biopsy of the right breast lump, which was conducted outside of the institute, showed malignant small round cell tumor. Post-excisional biopsy whole body 18-fluoro-deoxy-glucose positron emission tomography showed no residual uptake with no evidence of metastatic disease elsewhere. Immunohistochemistry work revealed positive expression of NKX2.2 and MIC2, which is consistent with the histopathological feature of EWS. Fluorescent in situ hybridization showed EWSR1 rearrangement, which is consistent with the diagnosis of EWS. The patient underwent a wide local excision of the right breast, followed by adjuvant chemotherapy consisting of 18 weekly vincristine/adriamycin D/cyclophosphamide regimen (vincristine, total dose of 2 mg; adriamycin D 100 mg; and cyclophosphamide 1.6 g). The patient was disease free after follow-up of 1 year. The rarity of primary breast EWS poses a diagnostic dilemma and hence the treatment. Local control with systemic therapy is the cornerstone of the treatment, in which breast conservation surgery is equivalent to mastectomy in patient with a good/average breast volume.

Correlation NKX2.2 IHC and EWSR1 break-apart FISH in the diagnosis of Ewing sarcoma: Can combined NKX2.2 and CD99 immunoexpression obviate or minimize the need of FISH testing? First assessment study from Indian tertiary cancer care center.

Ewing sarcoma (ES) are malignant small round cell tumors (MSRCT) characterized by rearrangements of EWSR1 gene. Although gold standard for diagnosis is detection of specific fusion genes by molecular testing, these ancillary tests are costly and only available in limited number of settings. There is a persuasive evidence for reliability of NKX2.2 immunohistochemistry (IHC) as a surrogate marker for EWSR1 gene rearrangement in ES. The aim of this study is to correlate the NKX2.2 immuno-expression with genetically confirmed ES cases and also to assess the reliability and accuracy of NKX2.2 along with combined positivity of NXX2.2 and CD99 in diagnosing ES and differentiating it from other relevant histological mimics. The present study is a retrospective study conducted over a period of 6-year duration in a tertiary cancer care center. We evaluated NKX2.2 immunoexpression in 35 genetically confirmed cases of ES and also in pertaining differential entities (n = 58) of ES including rhabdomyosarcoma (n = 20), lymphoblastic lymphoma (n = 14), Wilms tumor (n = 10), poorly differentiated synovial sarcoma (n = 4), small-cell osteosarcoma (n = 4), neuroblastoma (n = 5), and mesenchymal chondrosarcoma (n = 1). CD99 was performed in the category of MSRCTs showing NKX2.2 positivity to evaluate combined specificity for the diagnosis of ES. Of the 35 genetically confirmed cases of ES, 29 cases (83%) showed NKX2.2-positive expression (83% sensitivity). Compared to ES, NKX2.2 was positive in only 05% cases (3/58 cases) of non-ES MSRCT. Only two of five cases of neuroblastomas and one case of mesenchymal chondrosarcoma showed NKX2.2 positivity. CD99 positivity was seen in 100% of ES and in the single case of mesenchymal chondrosarcoma. All five cases (100%) of neuroblastoma were negative for CD99. The presented study, which is the first from an Indian oncology center, showed NKX2.2 IHC is quite reliable in diagnosis of ES in the right clinicopathological context. With remarkable sensitivity and specificity of NKX2.2 IHC for diagnosis of ES, we propose that combined positivity of CD99 and NKX2.2 IHC can obviate or minimize the need of EWSR1 gene rearrangement molecular testing for diagnosis of ES.

Categorizing Malignant Small Round Cell Tumors in Aspiration Cytology: An Institutional Experience.

The study aims to categorize malignant small round cell tumors (MSRCTs) originating in various sites of the body with the objective of utilization of cytomorphological features and ancillary techniques. It is a cross-sectional study conducted over a time span of 3 years (2017-2020). 33 cases of tumors with round cell morphology were evaluated by fine needle aspiration cytology (FNAC). The application of cell block preparation supported by immunohistochemistry aided in the categorization of 23 cases with definite diagnosis and the rest were reported as MSRCTs. Among the categorized 23/33 cases, the most common diagnosis was Ewing's sarcoma (7/23) followed by 6 cases of lymphoma. There were 2 cases each of rhabdomyosarcoma and Langerhans cell histiocytosis (LCH) and 1 case each of neuroblastoma, desmoplastic small round cell tumor (DSRCT), myeloid sarcoma, neuroendocrine tumor of pancreas, plasmacytoma, and small cell carcinoma. Histopathology confirmation was available in 24/33 cases. Among the categorized tumors (23/33), biopsy correlation was available in 19 cases, of which concordant result was seen in 17 cases (89.47%), which were 6 cases of lymphoma, 5 cases of Ewing's sarcoma (EWS), 2 of rhabdomyosarcoma, and 1 each of neuroblastoma, small cell carcinoma, DSRCT, and LCH. Discordant result was seen in one case of rhabdomyosarcoma and a case of synovial sarcoma reported as extraskeletal EWS in cytology. Out of the uncategorized cases reported as MSRTCs, histopathology was available in 5 cases which were diagnosed as rhabdomyosarcoma (1 cases), lymphoma (1 case), amelanotic melanoma (1 case), and extraskeletal EWS (2 cases). Categorization of MSRCTs should be done to implement appropriate therapeutic protocol. FNAC provides a rapid diagnosis contributing immensely for the timely management of the patient. Detailed cytomorphological evaluation serves as a guide for further evaluation by ancillary techniques leading to definitive diagnosis.

Primary intracranial extraosseous Ewing's sarcoma of the skull base in an elderly adult: illustrative case.

BACKGROUNDPrimary extraosseous intracranial Ewing’s sarcoma, also known as a peripheral primitive neuroectodermal tumor or “small round blue cell tumor,” is an extremely rare entity with limited representation in the literature beyond the pediatric population.OBSERVATIONSA 67-year-old male suffering occipital headache, nausea, and gait disturbance was found to have a large, avidly contrast-enhancing cerebellopontine angle mass extending into the cervical spinal canal with associated mass effect on medulla, cerebellum, fourth ventricle, and cervical spinal cord. This mass was not present on the imaging from 8 years prior. He underwent surgical debulking and pathology results demonstrated a malignant small round cell tumor showing diffuse immunopositivity for cytokeratins, CD99 and NKX2.2 with EWRS1-FLI1 rearrangement in 84% of the nuclei confirmatory of Ewing’s sarcoma. After 14 cycles of chemotherapy and 6 weeks of radiotherapy, 22 months after discovery, the patient remains in clinical and radiographic remission with complete return to his baseline functioning.LESSONSPrimary skull base extraosseous Ewing’s sarcoma should be considered in the differential diagnosis even in the elderly population when imaging studies demonstrate aggressive tumor growth patterns. Tumor debulking to establish a diagnosis followed by adjuvant chemoradiation therapy can result in clinical improvement with remission.

Microsurgical treatment of lumbar paravertebral tumors via lateral retroperitoneal approach: operative technique and a series of 6 patients

ObjectiveTo investigate the surgical techniques and postoperative therapeutic effectiveness of microsurgical treatment of lumbar paravertebral tumors via lateral retroperitoneal approach.MethodsThe clinical data of 6 cases with lumbar paravertebral tumors treated by lateral retroperitoneal approach in the Neurosurgery department of Xuanwu Hospital, Capital Medical University were analyzed retrospectively. The mean operation time, blood loss, incision length, length of hospital stay, and the resection rate of paravertebral tumors were collected, and the score of The Ability to Perform Activities of Daily Living (ADL) and incidence of postoperative complications was recorded.ResultsThe operation time ranged from 56 to 181 min, with an average of (94.8 ± 48.3) minutes. The blood loss was between 5 and 100 ml, with an average of (31.7 ± 37.5) ml. The incision length was 6–7 cm, with an average of (6.7 ± 0.5) cm. The hospitalization length was between 5 and 11 days, with an average of (8.7 ± 2.6) days. The resection rate of paravertebral tumors was 100%. Postoperative pathological diagnosis results revealed 4 cases of schwannoma, 1 case of ganglioneuroma, and 1 case of malignant small round cell tumor. During the 3-month follow-up, there were no tumor recurrence, abdominal infection, incision infection, incisional hernia, or death, and there was no significant decrease in the ADL score compared with that before the operation.ConclusionThe surgical treatment of lumbar paravertebral tumors via the lateral retroperitoneal approach has the advantages of the short operation time, minimally invasive procedures, quick postoperative recovery, and fewer complications.

Retroperitoneal blue cell round tumor (Ewing sarcoma in a 35years old male)- case report.

IntroductionEwing sarcoma is a highly aggressive tumor. It's common presentation is primary bone tumor, but very rarely as soft tissue sarcoma both of which are under the spectrum of Ewing sarcoma family of tumors (EFT).Case presentationA 35 years old male who presented with advanced locally spreading tumor. He was diagnosed after presenting with epigastric pain and melena, CT abdomen revealed the retroperitoneal mass. CT guided core biopsy taken and was diagnosed as Ewing sarcoma. The patient presented with mass already grown so he was not a surgical candidate. Patient was managed symptomatically till he was sent for palliative care in a Sarcoma centre in Jordon and passed away on October 2021.DiscussionEwing Sarcoma family of tumors are group of small round blue cell tumors that are histogenetically related. The better known is Ewing ‘s sarcoma (EWS). It is a malignant small blue round cell tumor with variable degree of neuroectodermal differentiation. Retroperitoneal tumor are mostly malignant and accounts for one third of soft tissue sarcoma. They usually present as large masses at the time of the diagnosis. So they do not produce symptoms until they grow large enough to compress or invade contagious structures.ConclusionES-EWS is an aggressive tumor with high incidence of local recurrence and distant metastasis that's why is was given its poor prognosis characteristic. Multimodality treatment including surgical resection, chemotherapy and High dose radiotherapy will help in better survival rate.

Peripheral primitive neuroectodermal tumor: a case report

BackgroundPrimitive neuroectodermal tumors are extremely rare and highly aggressive malignant small round cell tumors that arise from the primitive nerve cells of the nervous system or outside it. These tumors share similar histology, immunohistologic characteristics, and cytogenetics with Ewing’s sarcoma. Peripheral primitive neuroectodermal tumors of the chest wall are rare malignant tumors seen in children and young adults.Case presentationWe report a rare case of peripheral primitive neuroectodermal tumor in a 4-year-old Albanian girl with a mediastinal tumor and an unusual clinical presentation. She was initially treated for acute polyradiculoneuritis (Guillain–Barré syndrome) owing to pain, weakness in the lower limbs, and walking difficulty, as well as severe irritability. During the second week of treatment, the child began to experience dry cough, chest discomfort, and worsening dyspnea. Chest radiography, chest computed tomography, and contrast-enhanced computed tomography demonstrated a large mass in the right hemithorax that was derived from the posterior mediastinum with expansive growth in all directions and that shifted the mediastinal structures in the anterolateral left direction. Consequently, histopathology and immunohistochemical examination of the markers S-100, CD99, and Ki-67 showed that the tumor cells stained positively for S-100 and CD99. The proliferative index measured by Ki-67 was approximately 20%, which suggested primitive neuroectodermal tumor.ConclusionsEven though other diseases, including leukemia, lymphoma, and neuroblastoma, may be accompanied by musculoskeletal manifestations in children, other solid tumors, such as peripheral primitive neuroectodermal tumors, should be considered in the differential diagnosis in any child presenting with musculoskeletal symptoms.

Unknown primary malignant small round cell tumor masquerading as acute leukemia.

Unknown primary malignant small round cell tumor masquerading as acute leukemia.

“Wnt/β-catenin-activated Ewing's sarcoma with metastasis to pancreas:” A rare case report

Ewing's sarcoma (ES) family of tumors are aggressive tumors with high metastatic potential. Various unusual sites of metastasis have been reported, with pancreas being one of the exceptional sites. Herein, we report a case of a 21-year-old biopsied for a pancreatic mass and its histopathological evaluation revealed infiltration by a malignant small round cell tumor. Given that the patient was under treatment for ES of the right iliac bone an immunohistochemistry panel applied showed CD99, FLI-1 positivity proving it to be a metastasis. Furthermore, β-catenin put on clinical suspicion of solid pseudopapillary neoplasm was positive. Recent evidence suggest that elevated β-catenin expression is associated with poor outcomes, signifying Wnt/β-catenin signaling pathway contributes to disease progression. We not only report an uncommon metastasis of ES to the pancreas with four other cases reported so far but we also attempt to analyze probable correlation of β-catenin to disease advancement and its prognostic implication.

Primary Ewing sarcoma of the mesentery: An extremely uncommon case

Ewing sarcoma usually arises in the bones of children. Extra-skeletal Ewing sarcoma commonly occurs in soft tissue and rarely involves other organs of the body. The mesentery besides the intestine is an extremely uncommon location. The diagnosis poses a challenge as other malignant small round cell tumors come in the differential diagnosis in this location. Early histopathological diagnosis and immunohistochemical confirmation are crucial to outline an appropriate treatment plan. Expression of membranous CD99 and nuclear FLI-1 and NKX2.2 are fairly specific for diagnosis. The molecular study is reserved for difficult cases. Prognosis is poor in an extra-skeletal location in older individuals.