Histiocyte-rich rhabdomyoblastic tumor: a clinicopathological and molecular genetic analysis / 中华病理学杂志

Objective: To investigate the clinicopathologic and molecular genetic characteristics, diagnosis, differential diagnosis, treatment and prognosis of histiocyte-rich rhabdomyoblastic tumor (HRRMT). Methods: The clinical data of two cases of HRRMT diagnosed in Fujian Provincial Hospital and Fujian University of Traditional Chinese Medicine Affiliated People's Hospital from 2020 to 2021 were collected. Histopathology and immunohistochemical (IHC) staining were used to assess morphological changes; the genetic changes were analyzed with next-generation sequencing. The relevant literature was reviewed. Results: Both cases showed well-defined solid nodules and soft masses. Microscopically, the tumors had a fibrous pseudocapsule with lymphocytic aggregation, and locally invaded the surrounding skeletal muscle tissue, and the tumor cells were fusiform to epithelioid with an intensive foamy histiocytic infiltrate. No necrosis or mitosis was observed. Immunophenotyping showed the tumor cells were positive for desmin, either one or both skeletal muscle markers (myogenin or MyoD1), and negative for h-caldesmon, ALK and SMA. The Ki-67 index was<5%. Using next-generation sequencing, one case was found to harbour KRAS (G12D) and MSH3 (Q470*) mutations. Conclusions: HRRMT is a newly described skeletal muscle tumor with uncertain malignant potential. Its diagnosis and differential diagnosis depend on morphologic and IHC staining. No specific molecular genetics changes have been identified so far.

Histological variability and the importance of clinicopathological correlation in cutaneous Rosai-Dorfman disease

Abstract: Rosai-Dorfman disease is a benign histiocytic proliferative disorder of unknown etiology. The disease mainly affects lymph node tissue, although it is rarely confined to the skin. Here, we describe a 53-year-old woman with purely cutaneous Rosai-Dorfman disease. The patient presented with a large pigmented plaque on her left leg, and sparse erythematous papules on her face and arms. A complete clinical response was achieved with thalidomide, followed by recurrence at the initial site one year later. The histological examination displayed the typical features of Rosai-Dorfman disease in the recent lesions but not in the older lesions. In the setting of no lymphadenopathy, the histopathological features of Rosai-Dorfman disease are commonly misinterpreted. Therefore, awareness of the histological aspects present at different stages, not always featuring the hallmark microscopic signs of Rosai-Dorfman disease, is particularly important for a correct diagnosis of this rare disorder.

Histiocytoid Sweet's syndrome presenting with annular erythematous plaques

Abstract Histiocytoid Sweet's Syndrome is a rare inflammatory disease described in 2005 as a variant of the classical Sweet's Syndrome (SS). Histopathologically, the dermal inflammatory infiltrate is composed mainly of mononuclear cells that have a histiocytic appearance and represent immature myeloid cells. We describe a case of Histiocytoid Sweet's Syndrome in an 18-year-old man. Although this patient had clinical manifestations compatible with SS, the cutaneous lesions consisted of erythematous annular plaques, which are not typical for this entity and have not been described in histiocytic form so far. The histiocytic subtype was confirmed by histopathological analysis that showed positivity for myeloperoxidase in multiple cells with histiocytic appearance.

Type 2 leprosy reaction with Sweet's syndrome-like presentation

Abstract Leprosy is a chronic disease characterized by manifestations in the peripheral nerves and skin. The course of the disease may be interrupted by acute phenomena called reactions. This article reports a peculiar case of type 2 leprosy reaction with Sweet's syndrome-like features as the first clinical manifestation of leprosy, resulting in a delay in the diagnosis due to unusual clinical presentation. The patient had clinical and histopathological features reminiscent of Sweet's syndrome associated with clusters of vacuolated histiocytes containing acid-fast bacilli isolated or forming globi. Herein, it is discussed how to recognize type 2 leprosy reaction with Sweet's syndrome features, the differential diagnosis with type 1 leprosy reaction and the treatment options. When this kind of reaction is the first clinical presentation of leprosy, the correct diagnosis might be not suspected clinically, and established only with histopathologic evaluation.

Bone Marrow Suppression and Hemophagocytic Histiocytes Are Common Findings in Korean Severe Fever with Thrombocytopenia Syndrome Patients

The causes of cytopenia in patients with severe fever with thrombocytopenia syndrome (SFTS) are not fully understood until now. We reviewed the bone marrow (BM) findings of patients with SFTS to unravel the cause of the cytopenia. Three Korean SFTS were enrolled in this study. Thrombocytopenia, neutropenia, and anemia were detected in all three patients. Severe hypocellular marrow (overall cellularity <5%) and a decreased number of megakaryocytes were noted in one patient, and hypo-/normocellular marrow and an increased number of hemophagocytic histiocytes were observed in two patients. Megakaryocytes were relatively preserved in two patients. Although a limited number of cases are available, our observations suggest that both BM suppression and peripheral destruction or sequestration are causes of cytopenia of patients with SFTS. To the best of our knowledge, this is the first well documented pathologic evaluation of Korean SFTS.

A Case of Histiocytoid Variant Eccrine Sweat Gland Carcinoma of the Orbit

A 79-year-old male presented with left ocular pain. Evisceration and silicone ball implantation were performed after a diagnosis of phthisis. He returned six weeks later because of left facial erythematous swelling, tenderness, mild fever, chills and cough. His condition was diagnosed as orbital cellulitis. Despite two weeks of empirical antibiotic therapy, the symptoms worsened. A subsequent orbital computed tomography scan revealed enhanced soft tissue infiltrations in his left orbit and eyelid. Biopsy showed a diffusely infiltrating tumor of signet ring cell cytology. A systemic evaluation revealed multiple bone metastases. Based on this evidence, the patient was diagnosed with a very rare case of histiocytoid variant eccrine sweat gland carcinoma with multiple bone metastases.

Lepra histioide de Wade / Hystioid leprosy of Wade

En el presente artículo se expondrá un caso de lepra histioide de Wade, una forma clínico-histopatológica especial de lepra multibacilar caracterizada por la presencia de lesiones papulosas o nodulares correspondientes a lepromas conformados por histiocitos de morfología fusiforme. Se examinarán las características principales de esta forma particular de expresión de la lepra, sus diferencias con la forma clásica de presentación y los diagnósticos diferenciales que deben considerarse.

Efeitos da injeção intraorbitária de carboximetilcelulose 6.0% em coelhos: análise histológica e da mecânica ocular / Effects of intraorbital injection of 6.0% carboxymethylcellulose in rabbits: histological and ocular mechanics evaluation

OBJETIVO: Avaliar se a carboximetilcelulose 6,0% é capaz de atuar como modificadora do sistema oculomotor de coelhos por meio de forças de ação viscoelástica, a durabilidade de seu eventual efeito e reações teciduais à aplicação. MÉTODOS: Foram utilizados 25 coelhos da raça Nova Zelândia, divididos em dois grupos experimentais: um tratado com injeção peribulbar de carboximetilcelulose (CMC) 6,0 por cento e um controle que foi submetido à injeção peribulbar de 3,0 cc de soro fisiológico. No grupo tratado com CMC, variou-se o volume total injetado, obtendo-se, assim, quatro subgrupos (1,0, 1,5, 2,0 e 3,0 cc). Foram realizadas medidas da força necessária para promover movimentos tangenciais de adução, avaliação clínica e medidas da pressão intraocular antes, imediatamente após a injeção da substância e no 7º, 30º e 60º dia pós-operatório. A eutanásia dos animais foi realizada no 60º dia pós-operatório para análise histológica dos tecidos perioculares. RESULTADOS: A força média encontrada, 60 dias após a injeção da CMC 6,0 por cento, foi menor no subgrupo tratado 1,0 e maior nos subgrupos tratados 1,5, 2,0 e 3,0 relativamente à força antes da injeção. Nos subgrupos em que houve aumento da força, a análise histológica revelou processo inflamatório do tipo histiocitário com formação de fibrose e a presença da CMC nos tecidos perioculares. CONCLUSÕES: A carboximetilcelulose 6,0 por cento atuou como modificadora do sistema oculomotor de coelhos, podendo facilitar ou dificultar movimentos. Não foi possível concluir se o aumento da força deveu-se apenas ao processo inflamatório ou à soma de inflamação com um possível atrito viscoso provocado pela CMC.

PURPOSE: To determine the effects of 6.0% carboxymethylcellulose (CMC) in modifying the oculomotor system of rabbits by means of viscoelastic action forces, the durability of this effect and possible inflamatory reaction. METHODS: Twenty-five New Zealand rabbits were divided into two experimental groups: one treated with a peribulbar injection of 6.0 percent CMC and a control group submitted to peribulbar injection of 3.0 cc of physiological saline. The group submitted to peribulbar CMC injection was divided into four subgroups respectively receiving the following volumes: 1.0, 1.5, 2.0 and 3.0 cc. The force needed to promote tangential adduction dislocations, external ophthalmologic signs and intraocular pressure were evaluated. The animals were sacrificed on the 60th day after the injection for histological analysis. RESULTS: The mean force detected 60 days after the injection of 6.0 percent CMC was lower in the 1.0 treated subgroup and higher in the 1.5, 2.0 and 3.0 treated subgroups relative to the force before injection. Histological analysis revealed histiocytic infiltration with fibrosis in the subgroups in which there was an increase in force and the presence of CMC in periocular tissues. CONCLUSIONS: 6.0 percent CMC acted as a modifier of the oculomotor system of rabbits, facilitating or impairing movements. It was not possible to conclude whether the increase in force occurred as a consequence of the inflammatory process alone or of the sum of inflammation and a possible viscous attrition provoked by CMC.

Sinus Histiocytosis with Massive Lymphadenopathy: A Case Report with Pleural Effusion and Cervical Lymphadenopathy

Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare disorder characterized by a nonneoplastic proliferation of distinctive histiocyte cells within lymph node sinuses and lymphatics in extranodal sites. SHML occurs worldwide and is primarily a disease of childhood and early adulthood. A 26-yr-old man presented with painless palpable lymph node in cervical area. Radiographic studies revealed pleural effusion with lymphadenopathy and calcification in mediastinum. The cervical lymph node biopsy showed dilated sinuses filled with histiocytes with clear cytoplasm. The cells stained positive with CD68 and S-100. These cytologic and immunohistochemical findings were considered consistent with the diagnosis of SHML.

Histiocyte-Rich Reactive Lymphoid Hyperplasia of the Liver: Unusual Morphologic Features

Reactive lymphoid hyperplasia (RLH) of the liver is a rare entity and has also been termed nodular lymphoid lesion or pseudolymphoma of the liver. We report a case of hepatic RLH exhibiting unusual histiocyte-rich histologic features in a 47-yr-old woman in conjunction with a renal cell carcinoma. A follow-up computed tomography scan was done 14 months after a right radical nephrectomy for renal cell carcinoma revealed a nodular lesion in segment 5 of the liver. The lesion was interpreted as metastatic renal cell carcinoma or hepatocellular carcinoma based on the history of the patient and radiologic findings. Wedge resection of segment 5 was done with sufficient distance from the mass. Microscopically, the lesion was composed predominantly of peculiar histiocytic proliferation and was characterized by lymphoid aggregates forming a lymphoid follicle with germinal centers. The present case and prior cases reported in the literature suggest that RLH of the liver appear to be a heterogenous group of reactive inflammatory lesions that are often associated with autoimmune disease or malignant tumors.

Clinicopathological study of Kikuchi's disease.

Kikuchi's disease (KD) is a necrotizing lymphadenopathy with a self-limiting course commonly affecting young people. We conducted a clinico-pathological study of 20 cases of KD received at our department between July 2000 and December 2003. Our study confirmed that KD commonly involves the cervical lymph nodes of young adults, with a female predominance. One patient had associated cutaneous involvement. The hematological parameters were non-specific. The histological features were distinctive and included easy fragmentation on handling, karyorrhexis, crescentic histiocytes and the absence of neutrophils. The differential diagnosis on histology is also discussed.

Wegener's granulomatosis--an etiology of acute pancreatitis.

Wegener's granulomatosis is a systemic disease that usually involves the upper respiratory tract and kidneys. We report a 47-year-old man with Wegener's granulomatosis that presented as acute pancreatitis.

Sinus histiocytosis with massive lymphadenopathy--a review of seven cases.

Sinus histiocytosis with massive lymphadenopathy (SHML) also called as Rosai Dorfman disease is a rare histiocytic proliferative disorder of unknown etiology. Histological features currently define it. Persistent painless lymphadenopathy due to expansion of sinuses infiltrated with benign histiocytes and plasma cells and emperipolesis are the characteristic features of SHML. Our study includes seven cases (5 nodal and 2 extranodal) of SHML over a 5-year period whose slides and blocks were reviewed. IHC was performed on the main lesion, from a panel of S100, CD68, LCA, CD20, CD3, CD30, CD43, bcl2, cytokeratin and epithelial membrane antigen. In our series we have work up available in 7 cases out of which a detailed follow-up is available in 5 patients. Out of these 5 patients, 4 have a stable disease, while one developed histiocytic sarcoma after a gap of four years.

Rosai-Dorfman disease and juvenile xanthogranuloma in a Thai boy: report of a case.

A 3-year-old Thai boy suffered from two histiocytoses, Rosai-Dorfman disease (RDD) and juvenile xanthogranuloma (JXG). The patient first presented with massive cervical lymphadenopathy at the age of one year. Biopsy revealed typical RDD; abnormally large CD68- and S-100 protein-positive histiocytes with occasional emperipolesis filled up the sinuses. Two years later, he developed polyuria and polydypsia. Skull film demonstrated osteolytic lesions at the occiput and left parietal region. Enlargement of the pituitary stalk was found on the magnetic resonance imaging. Despite the clinical impression of Langerhans cell histiocytosis, biopsy of the occipital lesion disclosed numerous large histiocytes with foamy cytoplasm. Several Touton giant cells with wreath-like arrangement of the nuclei were also observed. The abnormal cells expressed CD68 and factor XIIIa, but were non-reactive with S-100 protein and CD1a. Biopsy of the pituitary stalk was not performed According to the authors' literature search, this represents the first report of RDD and JXG affecting the same person.

Primary oral tuberculosis: report of two cases.

Oral lesions of tuberculosis though uncommon, are seen in both the primary and secondary stages of the disease. In secondary tuberculosis, the oral manifestations may be accompanied by lesions in the lungs, lymph nodes, or in any other part of the body and can be detected by a systemic examination. Primary oral tuberculosis may present as a diagnostic challenge for the clinician. Here we report two patients with primary tuberculosis in the oral cavity who presented to the dental department, were diagnosed and referred for medical management.

Disseminated histoplasmosis with reactive haemophagocytosis presenting as PUO in an immunocompetent host.

Disseminated histoplasmosis (DH) with reactive haemophagocytosis has been described in literature mainly in immunocompromised hosts. Only sporadic case reports exist in immunocompetent hosts. Here, we present a rare case of DH with reactive haemophagocytosis in an immunocompetent host presenting as PUO.

Non-Langerhans cell histocytosis of the skin

Histiocytic proliferations may be reactive or neoplastic. The neoplastic proliferations [histiocytoses] are subdivided into a few categories. One of these categories is the non-Langerhan's cell histiocytoses [NLCH]. Cutaneous NLCH is a heterogeneous collection of conditions which can be sub grouped on the basis of the morphological appearance of the lesional histiocyte into xanthomatized, oncocytic, vacuolated, spindle-cell and polymorphous subtypes. The clinical characteristics and histological appearances of a variety of conditions within each subtype are discussed