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.

Gastric Xanthoma in the Pediatric Population: A Possible Herald for Malignancy? / 대한소아소화기영양학회지

Primary Histiocytic Sarcoma Presenting as a Breast Mass: A Case Report / 한국유방암학회지

Histiocytic sarcoma is a rare hematologic malignancy, with very few cases of primary histiocytic sarcoma of the breast described in English scientific literature. Herein, we describe a case of primary histiocytic sarcoma of the breast in a 75-year-old woman, with no clinical history of malignant tumors, who presented with a palpable solitary breast mass. Microscopically, the resected breast mass showed large pleomorphic cells, some multinucleated giant cells, and admixed inflammatory components. The pleomorphic tumor cells further showed a diffuse, noncohesive growth pattern, an abundant eosinophilic cytoplasm, and strong and diffuse immunoreactivity for cluster of differentiation (CD) 68 and CD163. Furthermore, a whole-body positron-emission tomography/computed tomography using deoxy-2-[¹⁸F]fluoro-D-glucose performed after surgery showed no other masses or lesions. After surgical excision, the patient was followed up, and no evidence of tumor recurrence or metastasis was noted.

A Case of Rosai-Dorfman Disease Presented with Neck Mass / 대한이비인후과학회지

Rosai-Dorfman disease, also known as the sinus histiocytosis with massive lymphadenopathy, is a rare and benign histioproliferative disease in which lymphadenopathy results from infiltration and dilatation of lymph node sinuses by large histiocytes. We experienced a case of a 59-year-old man, presenting bilateral cervical masses with pain since one month ago. Radiologically, there were multiple enlarged lymph nodes with homogenous contrast enhancement at both cervical areas. Excisional biopsy revealed that the tumor was consistent with the Rosai-Dorfman disease. The patient was treated successfully with corticosteroid. Herein, we report our experiences with literature reviews.

Adult Xanthogranuloma: A Clinical, Histopathological, and Immunohistochemical Study of 19 Korean Cases / 대한피부과학회지

BACKGROUND: Juvenile xanthogranuloma is a benign, self-limited disorder that usually occurs in infants and young children. Xanthogranuloma is rare in adults, and therefore studies reporting adult xanthogranuloma are limited. OBJECTIVE: We investigated the clinical, histopathological, and immunohistochemical characteristics of adult xanthogranuloma. METHODS: In this study, we evaluated 20 lesions in 19 patients with adult xanthogranuloma. RESULTS: A male predominance was observed (male : female ratio 1.4 : 1), and the mean age of patients was 35.1±16.3 years (range 15∼66 years), with the peak incidence observed in patients in their 20s. Notably, 65.0% of the lesions developed on the head and neck. The nodular form was more common than the papular form of this condition. Histopathological examination revealed dense monomorphic histiocytic infiltration without lipidization and scattered eosinophils without multinuclear giant cells in 5 lesions (25.0%), foamy histiocytic infiltration with variations of completely developed Touton giant cells in 10 lesions (50.0%), and fibrohistiocytic proliferation in 3 lesions (15.0%). On immunohistochemical examination, histiocytes including giant cells showed positive test results with Factor XIIIa (90.9%), vimentin (100%), and CD68 (100%) and negative test results with CD1a, smooth muscle actin, and S-100 protein stains. Tumor excision was the treatment for choice. CONCLUSION: Adult xanthogranuloma most commonly manifested as the nodular form of the disease on the head and neck of men in their late 20s. Histopathologically, the classic Touton cell-rich stage was most commonly observed, followed by the stage of early predominantly mononuclear infiltration. This was a single-center, small-sized retrospective study; however, we expect the results of this study to contribute to a better understanding of adult xanthogranuloma.

Pigmented Villonodular Synovitis Developing in the Knee of a Rheumatoid Arthritis Patient Mistaken as a Rheumatoid Arthritis Flare-Up / 대한내과학회지

Pigmented villonodular synovitis is a benign tumor arising from synovial fibroblasts or histiocytes. There are diffuse and localized forms: the former involves the entire synovium and the latter consists of nodules, small tumefactions, or pedunculated masses. The knee is the joint most commonly affected and the clinical diagnosis is difficult, so initial misdiagnosis is common. We report a case of pigmented villonodular synovitis developing in the knee of rheumatoid arthritis (RA) patient, mistaken for an RA flare-up.

Scanning electron microscopy of granuloma annulare

Abstract: Light microscopy of granuloma annulare shows mucin deposition with lympho-histiocytic infiltrate. We describe the ultrastructural three-dimensional aspects of a typical case of granuloma with characteristic histopathological findings. At the ultrastructural level, affected collagen bundles and granular mucin deposition were observed. Round cells corresponding to lymphocytes were identified. Bigger oval cells, corresponding to isolated or palisading histiocytes were also found. The ultrastructural aspects overlap with light microscopy and contribute to its iconographic documentation.

Occurrence of mesothelial/monocytic incidental cardiac excrescences in material from open-heart procedures: case reports and literature review

Mesothelial/monocytic incidental cardiac excrescences (MICE) are unusual findings during the histological analysis of material from the pericardium, mediastinum, or other tissues collected in open-heart surgery. Despite their somewhat worrisome histological appearance, they show a benign clinical course, and further treatment is virtually never necessary. Hence, the importance of recognizing the entity relays in its differential diagnosis, as an unaware medical pathologist may misinterpret it for a malignant neoplasm. Other mesothelial and histiocytic proliferative lesions, sharing very close histological morphology and immunohistochemistry features with MICE, have been described in sites other than the heart or the mediastinum. This similarity has led to the proposal of the common denomination "histiocytosis with raisinoid nuclei." We report three cases from the pathology archives of the Heart Institute of São Paulo University (Incor/HC-FMUSP), diagnosed as "mesothelial/monocytic incidental cardiac excrescence," with immunohistochemical documentation, and provide a literature review of this entity.

A case of cutaneous tuberculosis presenting with generalized xanthogranulomas

@#<p>A 33-year-old male had a 22-year history of generalized xanthogranulomas but had a normal lipid profile. He also developed ulcerating plaques on his arm and back that were consistent with cutaneous tuberculosis on histopathologic and polymerase chain reaction PCR studies. In a normolipemic patient with generalized xanthogranulomas, a reactive granulomatous response of histiocytes to infection is explored since these share a common CD 14+ precursor with the macrophages that are vital in tuberculosis.</p>

Erdheim-Chester Disease Presenting as an Anterior Mediastinal Tumor without Skeletal Involvement

Erdheim-Chester disease (ECD) is a form of non–Langerhans cell histiocytosis that most commonly involves the skeletal system. We report an unusual case of ECD presenting as an anterior mediastinal tumor without skeletal involvement. A 60-year-old man with no remarkable medical history was referred for evaluation of a mediastinal mass. The patient underwent surgical excision of the tumor via video-assisted thoracoscopic surgery. Histologic examination revealed marked proliferation of atypical histiocytes with sclerosis, and the results of immunohistochemical staining were suggestive of ECD.

Bilateral Frosted Branch Angiitis in Kikuchi-Fujimoto Disease

PURPOSE: A case of frosted branch angiitis in Kikuchi-Fujimoto disease is reported. CASE SUMMARY: A 33-year-old male complained of a sudden decrease in visual acuity that developed in both eyes 5 days prior. He suffered from a headache, chills, myalgia, and flank pain 1 week before. The initial best-corrected visual acuity (BCVA) was 0.1 in the right eye and 0.2 in the left eye. On slit lamp examination, no inflammatory finding was observed in the anterior chamber and vitreous body of both eyes. On fundus examination, a diffuse vascular sheathing-like frosted branch was found in the retinal vessels, and retinal hemorrhage was observed. Fluorescein angiography showed staining and leakage of dye along the vascular sheathing. Serological findings were negative, showing no evidence of an autoimmune disease or viral infection. Neck ultrasonography revealed non-tender left cervical lymph node enlargement >1 cm in diameter. Ultrasound-guided fine needle aspiration cytology showed findings compatible with Kikuchi-Fujimoto disease, including necrotic changes and pronounced karyorrhexis, plus histiocyte and lymphocyte infiltration without neutrophils. We started systemic steroid therapy. One month after treatment, the BCVA of both eyes improved to 1.0. CONCLUSIONS: In patients with frosted branch angiitis, systemic disease such as Kikuchi-Fujimoto disease should be considered.

IgG4-related Ophthalmic Disease Associated with Adult Xanthogranulomatous Disease

PURPOSE: To report a case of immunoglobulin G4 (IgG4)-related ophthalmic disease associated with adult xanthogranulomatous disease. CASE SUMMARY: A 38-year-old male with a history of cholecystectomy visited our clinic for bilateral periorbital swelling. Histopathology of the orbital biopsy showed diffuse infiltration of foamy histiocytes with Touton giant cells and lymphoid follicles, with a diagnosis of adult-onset xanthogranuloma. After excisional biopsy, he was treated with azathioprine and prednisolone. Four years after treatment, he again visited the clinic due to bilateral, yellowish eyelid masses. Serological examinations were all nonspecific findings, except for elevation of IgG and IgG4 levels. Magnetic resonance imaging showed bilateral symmetric soft tissue enlargement with slightly heterogeneous T1/T2 isosignal intensity, with contrast enhancement at the superolateral aspect of extraconal spaces. Excisional biopsy and blepharoplasty were performed. Immunohistochemical sections showed that the IgG4+/IgG plasma cell ratio was 10–20% and the IgG4 plasma cell count was 22/high power field (HPF). His past sections of 2013 from the pathology department were again stained and showed that the IgG4+/IgG plasma cell ratio was 40–50% and the IgG4 plasma cell count was 59/HPF. Thus, he was definitely diagnosed with IgG4-related ophthalmic disease. CONCLUSIONS: If there is recurrent eyelid swelling, IgG4-related ophthalmic disease should be considered as a differential diagnosis. And the patient with adult xanthogranulomatous disease can be diagnosed with IgG4-related ophthalmic disease.

A Case of Erdheim-Chester Disease Developed during Treatment of Leukemia in a Child / 임상소아혈액종양

Erdheim-Chester disease (ECD) is a rare non-Langerhan's cell histiocytosis disorder characterized by replacement of normal tissue by lipid-laden histiocytes affecting various organs. A few pediatric cases have been reported worldwide. Here we present a child with leukemia who was diagnosed as ECD. A 2-year and 11-month old boy diagnosed with high risk acute lymphoblastic leukemia (ALL) at the age of 17 months, received allogeneic hematopoietic stem cell transplantation (HSCT) at the age of 2 years old. Six months after the transplantation, the patient was admitted to the hospital with palpable left calf nodules. Bone marrow study suggested ECD without leukemia with complete chimerism status. Excisional biopsy of the left calf nodule showed ‘aggregation of non-Langerhan's cell type epitheloid histiocytes’; clinically suggestive of ECD. The patient was started on vinblastine and corticosteroid treatment.

The Relation between Tympanostomy Tube Otorrhea and Types of Immune Cells in Middle Ear Effusion in Children with Otitis Media with Effusion / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Tympanostomy tube insertion is one of the most common surgical procedures in children. Despite aseptic procedures with prophylactic antibiotic treatment, postoperative otorrhea may be encountered in some patients. The purpose of this study is to identify the relation between the types of immune cells in otitis media with effusion (OME) and tympanostomy tube otorrhea (TTO) in children. SUBJECTS AND METHOD: Fifty-six patients underwent tympanostomy tube insertion with OME were analyzed retrospectively. Fluid from OME was harvested by suction via syringe connector after myringotomy. Light microscopic examination of middle ear effusion was performed by a pathologist after hematoxylin and eosin staining. We analyzed the relation between the types of immune cells from middle ear effusion and TTO. RESULTS: Of 56 children, 36 were male and 22 were female. The mean age for tympanostomy tube insertion was 3.56 (±2.63) years, with the average follow-up period of 12.56 (±9.96) months. Neutrophils were detected in 19, eosinophils in 14, lymphocytes in 22, mast cells in 2, plasma cells in 7, and histiocytes in 9. TTO occurred in 15 patients. In patients with early TTO, eosinophils were detected more frequently than in patients without TTO (p=0.006). Plasma cells were detected more frequently in patient with late TTO than without TTO (p=0.011). CONCLUSION: According to the analysis of different types of immune cells, eosinophils in the middle ear effusion related with the occurrence of TTO.

Preoperative Cytologic Diagnosis of Warthin-like Variant of Papillary Thyroid Carcinoma

BACKGROUND: Warthin-like variant of papillary thyroid carcinoma (WLV-PTC) is a relatively rare variant of papillary thyroid carcinoma with favorable prognosis. However, preoperative diagnosis using fine-needle aspiration (FNA) specimens is challenging especially with lymphocytic thyroiditis characterized by Hürthle cells and lymphocytic background. To determine a helpful cytological differential point, we compared WLV-PTC FNA findings with conventional papillary thyroid carcinoma with lymphocytic thyroiditis (PTC-LT) and conventional papillary thyroid carcinoma without lymphocytic thyroiditis (PTC) regarding infiltrating inflammatory cells and their distribution. Preoperative diagnosis or potential for WLV-PTC will be helpful for surgeons to decide the scope of operation. METHODS: Of the 8,179 patients treated for papillary thyroid carcinoma between January 2007 and December 2012, 16 patients (0.2%) were pathologically confirmed as WLV-PTC and four cases were available for cytologic review. For comparison, we randomly selected six PTC-LT cases and five PTC cases during the same period. The number of intratumoral and background lymphocytes, histiocytes, neutrophils, and the presence of giant cells were evaluated and compared using conventional smear and ThinPrep preparations. RESULTS: WLV-PTC showed extensive lymphocytic smear with incorporation of thyroid follicular tumor cell clusters and frequent histiocytes. WLV-PTC was associated with higher intratumoral and background lymphocytes and histiocytes compared with PTC-LT or PTC. The difference was more distinct in liquid-based cytology. CONCLUSIONS: The lymphocytic smear pattern and the number of inflammatory cells of WLV-PTC are different from those of PTC-LT or PTC and will be helpful for the differential diagnosis of WLV-PTC in preoperative FNA.

Sarcomatous transformation of a hemosiderotic fibrohistiocytic lipomatous tumor: a case report / Transformação sarcomatosa de tumor lipomatoso fibro-histiocítico hemossiderótico: relato de caso

ABSTRACT Hemosiderotic fibrohistiocytic lipomatous tumors are rare neoplasms that were first described in 2000. Initially considered a benign lipotamous lesion of the soft tissues, nowadays they are considered to be a locally aggressive tumor. They occur mainly in the foot and ankle of women in their fifth and sixth decades, although they may be found in any place in the lower limbs and, more rarely, in other parts of the body. Histologically, hemosiderotic fibrohistiocytic lipomatous tumors consist of a mixture of mature adipose tissue, fusiform cell fascicles, macrophages that often contain cytoplasmic hemosiderin, mononuclear inflammatory infiltrate, and stroma that may be focally myxoid. Local recurrence is observed in nearly one-third of all cases. There is no consensus in the literature whether this tumor is a part of a spectrum that comprises pleomorphic hyalinizing angiectatic tumors and myxoinflammatory fibroblastic malignant tumors, or if it is an independent entity. The authors report a case of a neoplasia after a diagnosis of a hemosiderotic fibrohistiocytic lipomatous tumor in a 38-year-old woman, with two recurrences and later sarcomatous transformation. An immunohistochemical study indicated myofibroblastic differentiation of a malignant neoplasm. To the best of the authors' knowledge, there are only few reported cases of malignant transformation in hemosiderotic fibrohistiocytic lipomatous tumors.

RESUMO Os tumores lipomatosos fibro-histiocíticos hemossideróticos são neoplasias raras que foram descritas pela primeira vez em 2000. Inicialmente considerada uma lesão lipomatosa benigna dos tecidos moles, atualmente é considerado um tumor localmente agressivo. Essas lesões ocorrem principalmente no pé e no tornozelo das mulheres na quinta e sexta décadas de vida, embora possam ser encontrados em qualquer lugar nos membros inferiores e, mais raramente, em outras partes do corpo. Histologicamente, tumores lipomatosos fibro-histiocíticos hemossideróticos são formados por uma combinação de tecido adiposo maduro, fascículos de células fusiformes, macrófagos que contêm frequentemente hemossiderina citoplasmática, infiltrado inflamatório mononuclear e estroma, que pode ser focalmente mixoide. Há recidiva local em quase um terço dos casos. Não existe consenso na literatura se esse tumor faz parte de um espectro que envolve os tumores angiectásicos hialinizantes pleomórficos e os tumores fibroblásticos mixoinflamatórios malignos ou se configura uma entidade independente. Relatamos um caso de uma neoplasia com diagnóstico inicial de tumor lipomatoso fibro-histiocítico hemossiderótico em uma mulher de 38 anos, com duas recorrências e posterior transformação sarcomatosa. O estudo imuno-histoquímico indicou diferenciação miofibroblástica da neoplasia maligna. Encontramos apenas poucos casos relatados de transformação maligna de tumor lipomatoso fibro-histiocítico hemossiderótico.

Benign fibrous histiocytoma of the tongue: a case report / Histiocitoma fibroso benigno em língua: relato de caso

The fibrous histiocytoma is a soft tissue neoplasm that affects the dermis and the subcutaneous tissue, rarely is found in the oral cavity and perioral regions, and is originated from the proliferation of fibroblasts and histiocytes. The objective of this paper is to report a case of Benign Fibrous Histiocytoma in a 30-year-old male patient, complaining of a painless nodule in the tongue for about six months. With diagnostic clinical hypotheses of Fibrous Hyperplasia, Neurofibroma, Traumatic Neuroma, Fibrous Histiocytoma, Granular Cell Tumor or Ectomesenchymal Chondromyxoid Tumor a excisional biopsy was performed. The histopathological examination revealed a non-encapsulated proliferation of spindle cells with some giant multinucleated cells in the periphery of the lesion. Immunohistochemical reactions were performed, staining only for vimentin in the spindle cells and for CD68 in the multinucleated giant cells. According to these characteristics, the final diagnosis was Benign Fibrous Histiocytoma. The correct diagnosis of spindle shaped cell neoplasia must be performed with the aid of histopathological analysis and immunohistochemistry, mainly because the morphological similarities with other benign and malignant lesions. (AU)

O Histiocitoma Fibroso é uma neoplasia de partes moles que acomete a derme e o tecido subcutâneo, raramente é encontrado na cavidade oral e regiões periorais, e tem origem a partir da proliferação de fibroblastos ou histiócitos. O objetivo deste artigo é relatar um caso de Histiocitoma Fibroso Benigno em um paciente masculino, 30 anos de idade, com um nódulo indolor, bem delimitado, com duração de cerca de seis meses, localizado no dorso anterior da língua. Com as hipóteses clínicas diagnósticas de Hiperplasia Fibrosa, Neurofibroma, Neuroma Traumático, Histiocitoma Fibroso, Tumor de Células Granulares e Tumor Condromixoide Ectomesenquimal uma biópsia foi realizada sob anestesia local e a lesão foi fixada em formol a 10% e enviada para análise histopatológica. O exame histopatológico revelou uma proliferação não-encapsulada de células fusiformes com algumas células gigantes multinucleadas na periferia da lesão. A marcação imunohistoquímica foi positiva para CD68 nas células gigantes multinucleadas e para vimentina nas células fusiformes. O diagnóstico final foi de Histiocitoma Fibroso Benigno. Para um diagnóstico correto, este deve ser feito correlacionando características clínicas, análise histopatológica e imunohistoquímica devido à similaridade microscópica do Histiocitoma Fibroso com outras lesões com aspecto fusocelular, assim como similaridade clínica com outras lesões benignas e malignas.(AU)

Aggressive Indeterminate Dendritic Cell Tumor Mimicking Scalp Angiosarcoma

Indeterminate dendritic cell tumor (IDCT) is a proliferation of CD1a+, S100+ and langerin- histiocytes with a generally benign course. Here, we describe a case of a 90-year-old male who developed skin lesions on his scalp mimicking angiosarcoma and lymphadenopathy. He died six months after the onset of skin lesions despite of months' radiotherapy. Pathological examination ruled out scalp angiosarcoma and showed a high Ki-67 index. The appearance of skin lesions and lymphadenopathy led to challenges in diagnosis and the development of a treatment plan.

Sclerema Neonatorum in a Full-Term Infant Showing Favorable Prognosis

Sclerema neonatorum (SN) is a rare disease characterized by firm, indurated, waxy skin lesions extending throughout the body, sparing the fat-free soles, palms, and genitalia. The prognosis of SN is generally very poor, with a high fatality rate. We report the case of a full-term infant with delayed onset of SN showing good prognosis. A 4-month-old Korean male infant presented with diffuse waxy, sclerotic skin lesions on the whole body, sparing the face, nipples, and genital area, which began developing at 2 months of age. Histopathologic findings of the sclerotic skin lesions showed wide, fibrous intersecting bands in the subcutaneous fat tissue. Only sparse infiltration of lymphocytes and histiocytes was observed in the fat lobules and septa. Based on clinical presentation and histopathologic findings, he was diagnosed with SN. The patient survived with conservative care and had mild improvement of the skin lesions on his follow-up visit at 12 months of age.