Winny Varikatt

Superficial acral fibromyxoma: a report of two cases with radiological findings

Superficial acral fibromyxoma is a recently described soft tissue neoplasm with a predilection for the tips of the fingers and toes. As such it must be included in the radiological differential diagnosis of soft tissue lesions eroding bone in this location. The radiological features of this distinctive tumour have not so far been described. We report two cases with radiological and histopathological features.

Extraventricular neurocytoma with atypical features and ganglionic differentiation

Extraventricular neurocytoma (EVN) is an unusual variant of central neurocytoma located outside the ventricular system. Both tumours share a similar histology characterised by monotonous populations of round-to-oval cells with scanty cytoplasm separated by neuropil and branching capillaries. We report an EVN arising from the right frontal lobe near the olfactory tract in a 34-year-old male with worsening chronic epilepsy. Our patients tumour exhibited many uncommon features including ganglionic differentiation, increased mitotic activity and a high proliferative index. We discuss the important differential diagnoses given the site of the tumour as well as the differentiating features from olfactory neuroblastoma, oligodendroglioma, anaplastic ganglioglioma and supra-tentorial primitive neuroectodermal tumour.

Late onset Rasmussen's encephalitis with triple pathology

Rasmussens encephalitis is a devastating illness characterized by intractable focal seizures due to chronic localised encephalitis. We report on a rare variant of delayed onset Rasmussens encephalitis with triple pathology. A 27-year-old male, who was initially diagnosed with seizures when he was 16 years old, presented with focal seizures that became refractory to multiple anticonvulsants. Multiple investigations, including subdural electrode monitoring, revealed foci of onset in the right frontotemporal region. The patient underwent right front-temporal lobectomy. Post-operatively, the seizures became more severe and he developed new epilepsia partialis continua. Treatment with intravenous immunoglobulin was unsuccessful. He subsequently underwent a right hemispherectomy that rendered him seizure free. The three pathologies identified were old ischemic changes, type II cortical dysplasia and stage II Rasmussens encephalitis.

Cut-point for Ki-67 proliferation index as a prognostic marker for glioblastoma

Ki‐67 proliferation index (Ki‐67 index) is used to quantify cell proliferation during histopathological assessment of various tumors including glioblastoma (GB).

Cryoglobulinemic Glomerulonephritis Associated With Nodal and Renal Infiltration by T-Cell Lymphoma of T-Follicular Helper Phenotype: A Case Report

We present a unique case of cryoglobulinemic glomerulonephritis associated with nodal and renal infiltration by T-cell lymphoma of T-follicular helper phenotype. The patient presented with transient neurologic symptoms, severe nephritic syndrome with nephrotic-range proteinuria, and acute kidney injury. He had elevated double-stranded DNA levels, low complement levels, detectable cryoglobulin, and detectable immunoglobulin M (IgM) paraprotein. The kidney biopsy showed cryoglobulinemic glomerulonephritis with a membranoproliferative pattern and diffuse interstitial infiltrates on light microscopy; IgM, C3 but weak IgG, C1q, and negative C4d staining on immunofluorescence; and deposits with organized substructures on electron microscopy. Positron emission tomography showed diffuse uptake in bilaterally enlarged kidneys and a localized group of lymph nodes. Subsequent lymph node biopsy revealed Epstein-Barr virus-negative nodal T-cell lymphoma, which was also proven in renal tissue. The association between T-cell lymphoma, autoantibodies, and cryoglobulinemia may represent a paraneoplastic phenomenon. His renal prognosis has been excellent, but overall prognosis and survival is dictated by the clinical course of T-cell lymphoma.

Mesenchymal Chondrosarcoma in the Central Nervous System: Histological Diagnosis

Mesenchymal chondrosarcoma is a rare malignant neoplasm typically arising in the bones of young adults. It may also arise in somatic soft tissue, central nervous system and other organs. There are no specific clinical or radiological characteristics, and histological assessment remains the key to diagnosis. Histological features are similar regardless of site, and display a characteristic biphasic pattern composed of highly undifferentiated small round cells and islands of well differentiated hyaline cartilage. In this chapter, we discuss the clinical, radiological and histological features of mesenchymal chondrosarcoma arising in the central nervous system (CNS), the important differential diagnoses of small round cell tumour within the CNS, and the differentiating features of mesenchymal chondrosarcoma from Ewing sarcoma/PNET, medulloblastoma, haemangiopericytoma, monophasic synovial sarcoma and atypical teratoid/rhabdoid tumour.

Intravascular renal haemangioma resembling the red pulp of spleen arising from within the renal vein: a case report

Vascular tumours are very uncommon in the kidney and most of these have been described in single case reports. Some of these can be diagnosed radiologically so the histological features of many of these tumours are not well recognised. We report a case of a haemangioma arising from within the renal vein in a patient with chronic renal failure and bilateral adrenal cortical hyperplasia. The tumour has an unusual sinusoidal architecture and focal extrame-dullary haematopoiesis reminiscent of the spleen. As expected, the endothelial cells stain positively for CD31 and CD34 but negative for CD8. We will also briefly discuss the clinical and histological features of this unusual tumour based on literature reviews.

47. Central nervous system lymphomatoid granulomatosis

Lymphomatoid granulomatosis (LYG) is an angiocentric angio-destructive lymphoproliferative disorder mainly involving extra nodal sites composed of Epstein-Barr virus positive B cells admixed with reactive T cells which usually numerically predominate. While LYG commonly affects the lungs, other organs including skin, CNS, liver and kidneys can also be affected. Only on rare occasion is LYG limited to the CNS at presentation. A 39-year-old man presented with the symptoms suggestive of meningoenchephalitis and was treated symptomatically. After two months, the patient was re-admitted with fever and focal neurological signs. The CT scan of the brain showed haemorrhage and infarction involving both frontal lobes and temporal lobes with dilatation of the lateral ventricles. A brain biopsy showed changes consistent with a chronic inflammatory process. The patient’s condition deteriorated and he died on the 10 th day of admission. An autopsy limited to the brain examination was performed. The slices of the brain showed extensive necrotic and haemorrhagic lesions in frontal, temporal lobes, basal ganglia, cerebellum and brain stem. Histologically all lesions were composed of infiltrate of mixed population of T cells, B cells, histiocytes and plasma cells. The cells aggregated around the blood vessels and caused damage to the vessel wall and necrosis of the surrounding brain tissue. EBV-ISH staining showed 5-10 EBV positive B lymphocytes per/HPF, based on which a diagnosis of LYG, grade 2 was made (WHO). Conclusion LYG may rarely present with brain as the single site of involvement. A high index of suspicion, an adequate and representative sample of the brain lesion and EBV-ISH staining are important for diagnosis of LYG. Studies have shown value of histological grading in the management of LYG.

Lymphomatoid granulomatosis of lymph node

Lymphomatoid granulomatosis (LYG) is a rare Epstein-Barr virus (EBV) driven angiocentric and angiodestructive lympho-proliferative disorder predominantly involving extranodal sites; lymph nodes are rarely involved. We present an 80-year-old man with high-grade lymphomatoid granulomatosis with isolated cervical nodal involvement. He suffered from IgA monoglonal gammopathy and nephropathy for several years. He presented with fluctuating cervical lymphadenopathy for a few months. Repeated fine needle aspiration cytology (FNAC) was misleading, with necrosis and reactive lymphoid cells only, suggesting an infective process resulting in the patient receiving antibiotic treatment repeatedly. Flow cytometry was inconclusive. Excision biopsy of an enlarged submandibular lymph node demonstrated extensively necrotic lymph node and adjacent adipose tissue with a rim of viable lymphoid tissue. In the viable areas there was a polymorphic infiltrate of lympho-histiocytic cells and a significant population of large atypical cells with prominent and occasionally multiple nucleoli and mitoses. The blood vessels within necrotic areas and viable zones showed variable necrosis and transmural and periadventitial infiltrate of tumour cells. Immunohistochemical examination was diagnostic of grade 3 lymphomatoid granulomatosis. This case report highlights challenges faced by pathologists in accurate diagnosis of the condition as FNAC and flow cytometry are inconclusive. An emphasis on differential diagnosis, histological diagnostic features, treatment and prognosis is included.