Delayed Diagnosis of SMARCA4-Deficient Undifferentiated Tumor in a Heavy Smoker Male Patient: Discovered Through Bone Sampling, with Extensive Distant Metastases and Concurrent Granulomatous Disease, Leading to Patient Fatality.

Background. SMARCA4-deficient undifferentiated tumors are rare and pose a diagnostic challenge. This study delves into the intricate diagnostic terrain of SMARCA4-deficient undifferentiated tumors, providing insights into their diverse clinical presentations and diagnostic approaches. Case Presentation. A 69-year-old heavy-smoker man with adalimumab-treated rheumatoid arthritis presented with multiple lesions. A CT scan revealed a spiculated lung mass, enlarged mediastinal lymph nodes, and hepatic lesions. A whole-body FDG-PET/CT scan revealed heterogeneous hypermetabolic lesions in the lung, liver, and bone. Initial two core needle liver biopsies and a left upper lobe lung wedge resection initially indicated steatohepatitis and granulomatous formation with no evidence of malignancy. Several months later, the patient returned with left-sided flank pain and significant weight loss. CT scan identified a thigh mass, adrenal lesion, and extensive multiple skeletal lesions. A biopsy of the thigh mass revealed an extensively necrotic, epithelioid-to-spindled cell neoplasm with positive staining for pan keratin, focal staining for CD56, and a loss of nuclear expression of SMARCA4. A final diagnosis of SMARCA4-deficient undifferentiated tumor was rendered. Unfortunately, the patient's condition deteriorated, and he died a few weeks after receiving the final diagnosis. Conclusion. SMARCA4-deficient undifferentiated tumors have emerged as recent subjects of medical study, distinguished by their unique morphology and SMARCA4-deficient immunohistochemistry. These tumors present diverse clinical manifestations, affecting multiple organ systems. This report underscores the diagnostic complexities associated with complex clinical presentation and highlights the importance of multidisciplinary collaboration in addressing challenging clinical scenarios, particularly among heavy smoker male patients and intricate radiological presentations.

Myxoid neurofibroma masquerading as lymphatic-venous malformation and poses a diagnostic challenge on fine needle aspiration biopsy.

BACKGROUND: Myxoid neurofibromas (NF) are uncommon, benign spindle cell tumors that originate from peripheral nerve sheaths, often posing a diagnostic challenge due to their hypocellularity on cytology specimens. Distinguishing myxoid spindle cell lesions can be challenging, given the broad range of potential differential diagnoses. CASE PRESENTATION: A 26-year-old female with a past medical history of embolized inguinal, flank, and retroperitoneal venolymphatic malformation presented with a left pelvic pain causing significant disability. CT scan showed an extensive 8.7 cm × 6.6 cm retroperitoneal mass. FNA was performed and alcohol-fixed papanicolaou-stained smears showed a hypocellular specimen with loosely arranged clusters of bland spindle cell proliferation in the background of a mucoid matrix. Spindle cells showed scant cytoplasm and elongated oval-shaped regular nuclei. Prominent nucleoli were not seen. An excisional biopsy revealed a bland spindle cell proliferation in a myxoid background associated with shredded collagen bundles. Immunohistochemical staining showed diffuse positivity for S100 and CD34. Based on the overall findings, a definitive diagnosis of myxoid neurofibroma was rendered. DISCUSSION: Cytological features of myxoid neurofibroma include the presence of hypocellular spindle-shaped cells arranged in small, loosely organized groups within a myxoid matrix background. Cells exhibit scant cytoplasm with regular oval and elongated nuclei. Nucleoli are typically not identified. The differential diagnosis includes myxoid neurofibroma, myxoma, myxoid liposarcoma, myxoid chondrosarcoma, myxoid dermatofibrosarcoma protuberans, low-grade fibromyxoid sarcoma, and low-grade myxo-fibrosarcoma. CONCLUSION: We aim to highlight the importance of considering myxoid neurofibroma in the differential diagnosis of hypocellular myxoid spindle cell lesions encountered on fine-needle aspiration cytology.

Primary localized amyloidosis of the ureter with osseous metaplasia presenting as a suspicious ureteral mass.

Primary amyloidosis of the ureter is a rare disease that is difficult to distinguish from urothelial carcinoma. Only 50 cases of primary ureter amyloidosis have been reported since it was first described in 1937. Of these, only five cases of ureter amyloidosis with osseous metaplasia were reported. In this study, we report the clinical presentation of ureter primary amyloidosis that presented as a mass with osseous metaplasia. The aim of this study is to provide clinicians with knowledge about the clinical/radiologic manifestation that raise the suspicion of amyloidosis, bearing in mind the importance of differentiating it from other "malignant" processes.

Light chain deposition disease presenting as an atrial mass: a case report and review of literature.

Light chain deposition disease (LCDD) also known as nonamyloidotic immunoglobulin deposition disease is a rare systemic disorder due to the abnormal deposition of immunoglobulin in multiple organs caused by the clonal proliferation of B lymphocytes and plasma cells. Renal involvement is the most common with cardiac manifestations being the most common extra renal presentation of the disease. Renal involvement is not always associated with LCDD. Isolated cardiac involvement can manifest in a wide variety of ways: heart failure, cardiomyopathy, arrhythmias, angina, myocardial infarction, etc. We hereby present an unusual case of 59-year-old female who presented to clinic for routine follow up. A murmur on physical exam was evaluated with echocardiogram which led to the discovery of an incidental right atrial mass. Cardiac magnetic resonance imaging was completed 6 months later for follow up which showed increasing size of the mass. The mass was excised and found to be consistent with LCDD. To the best of our knowledge, this is the first reported case of LCDD manifesting as an atrial mass. Through this case report and review of literature we would like to generate awareness among our fellow pathologists and clinicians to maintain a high level of suspicion for LCDD as it can manifest in many unusual ways, with or without kidney involvement.

An Inguinal Perivascular Epithelioid Cell Tumor Metastatic to the Orbit.

Malignant PEComas are rare mesenchymal neoplasms. These tumors harbor distinct myomelanocytic phenotype. The PEComa family of tumors includes lymphangioleiomyomatosis, angiomyolipoma, clear cell sugar tumor of the lung, and myomelanocytic tumor of the falciparum ligament/ligamentum teres. PEComas have no known normal cell counterpart. Majority of PEComas are benign and occur predominantly in the middle-age women. These tumors are commonly encountered in the uterus. Herein, we report a 20-year-old woman with a left inguinal mass metastatic to orbit, brain, lumbar spine, and skin at presentation. To our knowledge, this is the first case of metastatic PEComa to the orbit. This is the third case of primary PEComa of the inguinal area.

Primary Peritoneal Angiosarcoma Metastatic to Liver and Bone without History of Radiation Therapy.

Angiosarcoma is a rare vascular soft tissue tumor of endothelial origin most commonly seen in the elderly as a primary cutaneous head and neck malignancy. Furthermore, a peritoneal angiosarcoma is an exceedingly rare entity. This is the second case of primary peritoneal angiosarcoma reported in literature that is not associated with prior radiotherapy. Herein, we describe a case of primary peritoneal angiosarcoma metastatic to both the liver and bone in a male patient with metachronous renal cell carcinoma and parathyroid adenoma.

Comparison of cell block preparation methods for nongynecologic ThinPrep specimens.

The purpose of this study was to compare four cell block (CB) methods in the setting of nongynecologic ThinPrep (TP) specimens. 48 CBs were prepared from 12 nongynecologic TP specimens using the following CB methods: (1) Inverted filter sedimentation (IFS); (2) Thrombin method; (3) Albumin method; (4) Simple sedimentation. Each CB was assigned a cellularity score: 0 no cells, 1+ hypocellular, 2+ hypocellular with tissue fragments, 3+ cellular. A score of 2+ or 3+ was given for 11/12 of thrombin, 7/12 IFS, 5/12 albumin, and 2/12 simple sedimentation CBs. Thrombin CBs demonstrated a pale background clot with evenly distributed cells. Albumin CBs had a cracked uneven background. IFS CBs had a clear background, but were technically difficult and cells appeared artifactually crowded. In the setting of nongynecologic TP specimens, the thrombin CB was easily prepared and produced the best CB in regards to cellularity, cell distribution, and background quality.

Cytologic findings of lymphangioleiomyomatosis in pleural effusion: a case report.

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a rare disease occurring almost exclusively in females of reproductive age. Patients usually present with insidious and progressive dyspnea. Episodes of hemoptysis, pneumothorax, and chylothorax may occur, and the patient progresses to eventual respiratory failure and death. The characteristic pathologic finding is proliferation of immature smooth muscle cells (LAM cells) in the lungs, lymphatics and lymph nodes of thorax and abdomen/ retroperitoneum. CASE: A 47-year-old woman with a 1-year history of LAM diagnosed on iliac lymph node biopsy presented with progressive dyspnea and pleural effusion. A chest tube was placed. The collected pleural fluid, which represented chylothorax, yielded cohesive clusters of cells consisting of 2 cell populations: an outer, discontinuous layer of flattened cells and an inner portion of ovoid spindle cells. By immunohistochemistry the inner cells stained with smooth muscle actin and were negative for keratin. CONCLUSION: The characteristic constellation of clinical findings and distinctive cytology in conjunction with immunohistochemistry staining can render the diagnosis of LAM in effusions.