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.
Carcinoma, Renal Cell/pathology ; Female ; Histiocytes/*pathology ; Humans ; Kidney Neoplasms/pathology ; Liver Diseases/*pathology ; Middle Aged ; Pseudolymphoma/*pathology

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.
Biomarkers, Tumor/analysis* ; Diagnosis, Differential ; Histiocytes/pathology* ; Humans ; Molecular Biology ; Muscle Neoplasms/pathology* ; Prognosis

Histiocytes/pathology* ; Humans ; Lymphoma, Extranodal NK-T-Cell/pathology* ; Nose Neoplasms/surgery*

ln an attempt to clarify the dual origin histiocytes and to reclassify histiocytic proliferative disorders according to their immunohistochemical properties, normal histiocytes and histiocytes in selected proliferative disorders were stained using the peroxidase-antiperoxidase method for lysozyme, 1-antichymotrypsin and for S-100 protein. The proliferated histocytes of cosinophilic granutoma and Letterer-siwe disease were strongly immunoreactive for S-100 protein. In histiocytic medullary reticulosis (HMR) and in histiocytic lymphoma, all three markers were found within the tumor cells. ln fibrous histiocytoma and in juvenile xanthogranuloma, only a few weakly immunoreactive cells for S-100 protein were observed. lnflammatory malignant fibrous histiocytoma(MFH) (Xanthosarcoma) and xanthoma were immunoreactive for 1-antichymotrypsin and lysozyme respectively. ln MFH of the storiform -pleomorphic type and in atypical fibroxanthoma, stains using all of the histiocytic markers were negative. These results suggest that eosinophilic granuloma. Letterer-Siew disease, fibroxanthoma and juvenile xanthogranloma are proliferative disorder of T-zone histiocytes; HMR and histiocytic lymphoma are those of pluripotential stem cells capable of dual histiocytic differentiation; xanthoma and xanthosarcoma are monocytic proliferative disease; and MFH of the storiform-pleomorphic type and atypical fibroxanthoma are not true histiocytic diseases.
Histiocytes/*metabolism ; Human ; Immunohistochemistry ; Reticuloendotheliosis/classification/*metabolism/pathology ; S100 Proteins/metabolism ; Support, Non-U.S. Gov't

Xanthogranulomatous cholecystitis is an extremely rare benign inflammatory disease of the gall bladder characterized by yellowish focal nodular appearance with tissue necrosis and lipid-containing histiocyte (xanthomacell). Recently, we experienced a case of xanthogranulomatous cholecystitis. A 71-year old woman was admitted with the complaints of RUQ pain for 1 month. On abdominal ultrasound examination, there were diffuse gallbladder wall thickening, echogenic nodule with acoustic shadow, the calculous cholecystiti and the gall badder cancer were strongly suspected and the operation was performed. At operation the gall bladder was marked enlarged and wall thickening with two brownish, oval shaped, smooth surfaced stones. The specimen was revealed a xanthogranulomatous cholecystitis by the pathology.
Acoustics ; Aged ; Cholecystitis* ; Female ; Gallbladder ; Histiocytes ; Humans ; Necrosis ; Pathology ; Ultrasonography ; Urinary Bladder

Dendritic Cells ; pathology ; Histiocytes ; pathology ; Histiocytosis, Langerhans-Cell ; pathology ; Humans ; Keratins ; analysis ; Langerhans Cells ; pathology ; Lymphoma, Large B-Cell, Diffuse ; pathology ; Sarcoma ; chemistry ; classification ; pathology

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.
Aged ; Carcinoma/*diagnosis/pathology ; *Eccrine Glands ; Histiocytes/*pathology ; Humans ; Male ; Orbital Neoplasms/*diagnosis/pathology ; Positron-Emission Tomography ; Sweat Gland Neoplasms/*diagnosis/pathology ; Tomography, X-Ray Computed

Antigens, CD ; immunology ; Antigens, Differentiation, Myelomonocytic ; immunology ; Child, Preschool ; Diagnosis, Differential ; Histiocytes ; immunology ; pathology ; Histiocytosis, Sinus ; diagnosis ; pathology ; Humans ; Lymph Nodes ; immunology ; pathology ; Lymphatic Diseases ; diagnosis ; pathology ; Male

PURPOSE: Giant cell tumor is the second most common benign neoplasm in upper extremity. Unlike usual chief complaint of painless mass, an atypical case with giant cell tumor presented a distinguishing characteristics of which accompany pain and tenderness and is histologically giant-cell free. METHODS: A 31-year-old male patient complained of a rapid growing painful mass on the proximal phalanx of the left ring finger. Under microscopic operation, a 1.6 x 1.3cm sized mass was found to be surrounded by areolar tissue and attached to a tendon sheath, encircling the digital nerve and artery. Diagnostic confirmation was assisted by positive finding in histologic immunohistochemical stain-CD68. Characteristic pathologic finding is an atypical distribution of spindle cells & histiocytes without giant cells in fascicular pattern. RESULTS: Giant cell tumor was carefully removed under microscopic approach, while preserving digital nerve & artery. In postoperative 13th month, the patient presented with a 6mm of static two-point discrimination test, similar to that of the adjacent fingers. CONCLUSION: We report an atypical case with painful mass on tendon sheath, surrounding the digital nerve and artery that was diagnosed of giant cell tumor, but without giant cells on pathology. This case provides broader understanding of the giant cell tumor that should not only rely its typical findings of the painless mass and positive sign on H&E stain.
Adult ; Arteries ; Discrimination (Psychology) ; Fingers ; Giant Cell Tumors* ; Giant Cells* ; Histiocytes ; Humans ; Male ; Pathology ; Tendons ; Upper Extremity

We reviewed clinical and pathologic characteristics of 18 cases of malignant histiocytosis including 2 autopsy cases with special interest on their immunohistochemical characteristics. We report 3 cases of unusual immunohistochemical finding and postulate these cases may be a supportive evidence of the view that dendritic cells share common precursor with those of mononuclear phagocytic system. More accumulated cases in the future and careful analysis would be needed to answer the basic question about the origin of malignant histiocytosis.
Adolescent ; Adult ; Antigens, Differentiation/analysis ; Biopsy ; Child ; Dendritic Cells/pathology ; Female ; Histiocytes/pathology ; Histiocytic Sarcoma/immunology/*pathology ; Humans ; Male ; Middle Aged ; Tumor Markers, Biological/analysis