ABSTRACT Background Fibrous hamartoma of infancy (FHI) is a rare soft tissue lesion arising as a subcutaneous mass involving the axilla, trunk, and upper arm in infants and children <2yrs. Sarcomatous transformation in FHI is described in anecdotal cases in the literature. Case Report We describe one such example arising as a mass in the lower back in a 3-month-old infant. On histology, the tumor contained classic triphasic morphology; however, brisk mitotic activity noted at multiple foci was diagnostically challenging to categorize. The tumor was evaluated for ETV6-NTRK3 fusion to exclude other common differentials. Conclusion While FHI may be frequently encountered in infants, rare sarcomatous transformation are known to occur and merits special attention as it can be misdiagnosed. Also, a close follow-up is warranted as the lesion is known to recur locally.

Abstract We present a case of a late preterm intrauterine growth-restricted neonate with isolated and persistent severe thrombocytopenia. At birth, the neonate did not have a complete clinical spectrum of congenital rubella syndrome (CRS) but later developed peculiar findings that helped clinch the diagnosis. The neonate also had interstitial pneumonia and died secondary to superimposed acute viral infection leading to acute respiratory distress syndrome. The serology was positive for IgM antibodies against the rubella virus. The constellation of clinical manifestations of congenital rubella in the presence of positive IgM antibody against rubella and consistent histopathology confirmed the diagnosis of CRS.

ABSTRACT Cardiac lymphoma is a rare entity. In this setting, the secondary involvement of the heart is far more frequent than the primary cardiac lymphoma. Herein, we present an autopsy case of a disseminated anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma with a dominant mediastinal involvement. Extensive cardiac infiltration with the near replacement of the myocardial wall by the neoplastic cells was observed. A total of nine isolated case reports of anaplastic large cell lymphoma with cardiac involvement were found in the English-language literature, and a widespread cardiac and thymic infiltration by the systemic ALK-positive anaplastic large cell lymphoma has not been documented. An incidental regenerative nodule was also identified in the liver. The patient died of pulmonary thromboembolism and cardiac arrest.

ABSTRACT We describe an unusual case of lymphomatosis cerebri in a middle-aged lady presenting with rapid-onset dementia. The lymphomatous infiltrate, instead of forming mass lesions, percolated throughout the brain parenchyma, which is often missed on a stereotactic biopsy and hence warrants caution and awareness about this entity. The nonspecific symptoms at presentation and a variable picture at imaging make this entity diagnostically challenging.

ABSTRACT Multicystic encephalomalacia is varying sized cystic lesions in the brain encountered in developing fetuses or infants. These cysts start at the periventricular area and may extend onto the cortex. The cause of the formation of these cystic lesions is secondary to an ischemic or hypoxic insult, which leads to liquefactive necrosis and subsequent formation of gliotic cyst walls having an admixture of microglia. We discuss four autopsy cases that had multicystic encephalomalacia to highlight the scenarios in which these lesions are encountered.

ABSTRACT Spinal muscular atrophy (SMA) is a heritable neuromuscular disorder which encompasses a large group of genetic disorders characterized by slowly progressive degeneration of lower motor neurons. The mutation is seen in the SMN1 gene mapped on chromosome 5. Depending on the age of the onset and the degree of severity, SMA has three subtypes. We discuss the autopsy findings in a case of Type 1 SMA also known by the name Werdnig-Hoffmann disease, to highlight the primary changes in the spinal cord, and skeletal muscle with association changes in the liver and terminal respiratory complications.

ABSTRACT We describe an autopsy case of a 45-year-old male diagnosed with autosomal dominant polycystic kidney disease who presented with complaints of altered sensorium. The autopsy revealed multiple tumor-like masses in the liver, which on histological examination depicted multiple large suppurative granulomas with the presence of variable acid-fast coccobacilli (consistent with Brucella spp.). Interestingly, extensive amyloid deposition in multiple organs was noted. To the best of our knowledge, this is the first case of chronic brucellosis causing tumor-like abscesses in the liver accompanied by secondary systemic amyloidosis in a patient with underlying autosomal dominant polycystic kidney disease.

ABSTRACT Langerhans cell histiocytosis (LCH), a disorder of antigen-presenting cells, is the commonest disorder of the mononuclear phagocytic system. Diagnosis is always challenging due to heterogeneous clinical presentation. However, with the evolution and better understanding of its biology, many of these children are being diagnosed early and offered appropriate therapy. Despite these advances, in developing countries, an early diagnosis is still challenging due to resource constraints for specialized tests. As a result, many patients succumb to their disease. Autopsy data on LCH is notably lacking in the literature. We sought to analyze the clinical (including mutational) and morphologic features at autopsy in six proven cases of LCH. This study includes a detailed clinico-pathological and mutational analysis of 6 proven cases of LCH. Presence of BRAF V600E mutation was assessed by both Real Time PCR and Sanger sequencing. A varied spectrum of organ involvement was noted with some rare and novel morphological findings, like nodular bronchiolocentric infiltration of LCH cells, lymphovascular emboli of LCH cells, and paucity of eosinophils within the infiltrate; these features have not been described earlier. Surprisingly, all cases were negative for BRAF V600E mutation on both RQ-PCR and Sanger sequencing. The present study is perhaps the first autopsy series on LCH. This extensive autopsy analysis represents a correlation of pathological features with clinical symptoms which provides clues for a timely diagnosis and appropriate therapeutic intervention. Also, our findings hint at the low frequency of BRAF V600E mutation in our LCH patients.