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Diagnostic Cytopathology Jun 2024Spindle epithelial tumor with thymus-like elements (SETTLE) is a rare biphasic thyroid tumor with low malignant potential that has a distinct morphology. Despite fine...
Spindle epithelial tumor with thymus-like elements (SETTLE) is a rare biphasic thyroid tumor with low malignant potential that has a distinct morphology. Despite fine needle aspiration (FNA) being a common method for evaluating thyroid nodules and lymph nodes, there are limited cytologic descriptions of SETTLE in the literature due to its rarity. As a result, SETTLE is frequently underdiagnosed or misdiagnosed as medullary carcinoma, thymoma, teratoma, synovial sarcoma, or solitary fibrous tumor, among others. We present a case of a 28-year-old man with a history of a hemithyroidectomy diagnosed as SETTLE found to have a neck nodule along the strap muscle suspicious for recurrence 5 years post-surgery. The ultrasound-guided FNA cytology specimen of the neck nodule showed loosely cohesive, monomorphous ovoid to spindled cells with scant cytoplasm and nuclei with fine to granular chromatin. In addition, there were occasional clusters of cells with a papillary configuration. The tumor cells were associated with magenta, amorphous extracellular material. Immunocytochemical staining of the cell block material revealed that tumor cells were positive for p63, cytokeratin AE1/3, and CK8/18 and negative for TTF-1 and thyroglobulin. Overall, the morphological and immunocytochemical findings were consistent with a local recurrence of SETTLE. The subsequent left anterior strap mass excision revealed a 4 cm encapsulated tumor consistent with SETTLE. Because ofits rarity and low level of awareness, SETTLE poses a diagnostic and therapeutic challenge. We herein present the cytologic findings of monomorphic SETTLE and highlight the potential cytomorphologic and immunophenotypic pitfalls. We also highlight how tumors with high-risk features can be a therapeutic challenge.
Topics: Humans; Male; Adult; Neoplasm Recurrence, Local; Thyroid Neoplasms; Neoplasms, Glandular and Epithelial; Biopsy, Fine-Needle; Biomarkers, Tumor
PubMed: 38520309
DOI: 10.1002/dc.25301 -
Cell Mar 2024Proprioception tells the brain the state of the body based on distributed sensory neurons. Yet, the principles that govern proprioceptive processing are poorly...
Proprioception tells the brain the state of the body based on distributed sensory neurons. Yet, the principles that govern proprioceptive processing are poorly understood. Here, we employ a task-driven modeling approach to investigate the neural code of proprioceptive neurons in cuneate nucleus (CN) and somatosensory cortex area 2 (S1). We simulated muscle spindle signals through musculoskeletal modeling and generated a large-scale movement repertoire to train neural networks based on 16 hypotheses, each representing different computational goals. We found that the emerging, task-optimized internal representations generalize from synthetic data to predict neural dynamics in CN and S1 of primates. Computational tasks that aim to predict the limb position and velocity were the best at predicting the neural activity in both areas. Since task optimization develops representations that better predict neural activity during active than passive movements, we postulate that neural activity in the CN and S1 is top-down modulated during goal-directed movements.
Topics: Animals; Proprioception; Neurons; Brain; Movement; Primates; Neural Networks, Computer
PubMed: 38518772
DOI: 10.1016/j.cell.2024.02.036 -
Cureus Feb 2024Background and objective Rhabdomyosarcoma (RMS) is a rare and malignant mesenchymal tumor characterized by skeletal muscle differentiation. While it is a common soft...
Background and objective Rhabdomyosarcoma (RMS) is a rare and malignant mesenchymal tumor characterized by skeletal muscle differentiation. While it is a common soft tissue sarcoma in children, its incidence significantly decreases with advancing age, rendering it exceptionally rare in individuals aged more than 45 years. This study aimed to shed light on the clinicopathological diversity and subtypes of RMS, thereby providing a comprehensive overview for enabling diagnostic precision and therapeutic strategies in treating this infrequently encountered malignancy in adults. Methodology This was a hospital-based cross-sectional study conducted in the Department of Pathology. Patients who were diagnosed with RMS over a period of three years were included in the study. The demographic features such as age and sex and aspects related to the tumor site, size, subtypes of RMS, and immunohistochemical expression were studied. Results A total of 14 cases were included in our study. The age at diagnosis ranged from four months to 65 years with a male-to-female ratio of 1:2.5. The sites of presentation were head and neck, trunk, pelvis, genitourinary tract, and retroperitoneum. The histological types were embryonal, alveolar, pleomorphic, and mixed and spindle cell types. The tumor cells were positive for immunohistochemistry markers desmin, MyoD1, and vimentin. Conclusion This study delved into the clinicopathological intricacies of RMS, offering comprehensive insights into its diverse subtypes. Our findings underscore the unique presentation of RMS in adults, with trunk and genitourinary tracts emerging as primary sites and alveolar and pleomorphic RMS observed as the predominant histological subtypes. Furthermore, the study sheds light on rare subtypes with distinct anatomical distributions.
PubMed: 38500901
DOI: 10.7759/cureus.54341 -
International Journal of Surgical... Mar 2024Rhabdomyosarcoma is a highly malignant tumor with striated muscle differentiation, which is histologically classified as alveolar, embryonal, pleomorphic, and spindle...
Rhabdomyosarcoma is a highly malignant tumor with striated muscle differentiation, which is histologically classified as alveolar, embryonal, pleomorphic, and spindle cell/sclerosing histological subtype. Rhabdomyosarcoma with rearrangement, which usually occurs in the bone, is a newly identified rare spindle and epithelioid rhabdomyosarcoma with characteristic clinicopathological features and molecular alterations. We report a 39-year-old female patient who underwent local excision of the mandibular lesion. Microscopically, the intraosseous tumor was composed of spindle-shaped, epithelioid, and rhabdomyoblastic cells with atypical nuclei and atypical mitotic figures. In addition, rearrangement was revealed by the fluorescence in situ hybridization. The tumor was thus correctly diagnosed as rhabdomyosarcoma with rearrangement. The patient was scheduled to undergo radiotherapy, and triple-agent chemotherapy after surgery, and no tumor recurrence or metastasis was detected during the 3-month postoperative follow up. Since this tumor is relatively rare and newly recognized, it can be easily misdiagnosed or missed and might be a conundrum of pathological diagnosis. Familiarity with its clinicopathological features and molecular alterations is essential for its correct diagnosis. Therefore, we summarized the clinicopathological, immunohistochemical, and molecular alterations of 43 cases of this rare rhabdomyosarcoma variant in the English-language literature. In addition, the differential diagnosis of this lesion is crucial either.
PubMed: 38500382
DOI: 10.1177/10668969241239676 -
Surgical Case Reports Mar 2024Inflammatory myofibroblastic tumor (IMT) of the stomach is an uncommon mesenchymal neoplasm. We present a case of gastric submucosal tumor (SMT) where the final...
BACKGROUND
Inflammatory myofibroblastic tumor (IMT) of the stomach is an uncommon mesenchymal neoplasm. We present a case of gastric submucosal tumor (SMT) where the final diagnosis was IMT.
CASE PRESENTATION
A 69-year-old man presented with a 24-mm SMT on the posterior wall of the middle third of the stomach that was detected by screening upper gastrointestinal endoscopy. Abdominal contrast-enhanced computed tomography showed that the tumor was well-enhanced. Although endoscopic ultrasonography-guided biopsy was performed, the histological diagnosis was not confirmed preoperatively. Since the tumor was clinically suspected to be a gastrointestinal stromal tumor, we performed gastric wedge resection by laparoscopic-endoscopic cooperative surgery. Pathologically, proliferative spindle cells with a positive reaction for smooth muscle actin, negativity for c-kit, desmin, s-100, CD34, STAT-6, β-catenin and anaplastic lymphoma kinase 1 were identified. Hence, the tumor was finally diagnosed as an IMT originating from the stomach.
CONCLUSIONS
When an SMT of the stomach is identified, the possibility of gastric IMT should be considered.
PubMed: 38485843
DOI: 10.1186/s40792-024-01844-7 -
Hepatology Research : the Official... Mar 2024A 70-year-old man undergoing treatment for immunoglobulin G4-related disease developed a liver mass on computed tomography during routine imaging examination. The tumor...
A 70-year-old man undergoing treatment for immunoglobulin G4-related disease developed a liver mass on computed tomography during routine imaging examination. The tumor was located in the hepatic S1/4 region, was 38 mm in size, and showed arterial enhancement on dynamic contrast-enhanced computed tomography. We performed a liver biopsy and diagnosed moderately differentiated hepatocellular carcinoma. The patient underwent proton beam therapy. The tumor remained unchanged but enlarged after 4 years. The patient was diagnosed with hepatocellular carcinoma recurrence and received hepatic arterial chemoembolization. However, 1 year later, the patient developed jaundice, and the liver tumor grew in size. Unfortunately, the patient passed away. Autopsy revealed that the tumor consisted of spindle-shaped cells exhibiting nuclear atypia and a fission pattern and tested positive for α-smooth muscle actin and vimentin. No hepatocellular carcinoma components were observed, and the patient was pathologically diagnosed with hepatic leiomyosarcoma. Next-generation sequencing revealed somatic mutations in CACNA2D4, CTNNB1, DOCK5, IPO8, MTMR1, PABPC5, SEMA6D, and ZFP36L1. Based on the genetic mutation, sarcomatoid hepatocarcinoma was the most likely pathogenesis in this case. This mutation is indicative of the transition from sarcomatoid hepatocarcinoma to hepatic leiomyosarcoma.
PubMed: 38459823
DOI: 10.1111/hepr.14034 -
Diagnostic Cytopathology Jun 2024A mesonephric-like endometrial adenocarcinoma (ML-EAC) is very rare and has a worse prognosis than other endometrial carcinomas. We describe an ML-EAC and report our...
A mesonephric-like endometrial adenocarcinoma (ML-EAC) is very rare and has a worse prognosis than other endometrial carcinomas. We describe an ML-EAC and report our endometrial cytological findings. A 76-year-old woman presented with irregular genital bleeding and a uterine mass. Endometrial cytology revealed atypical cylindrical or spindle-shaped cells in the form of small aggregates or solitary cells. The cell aggregates exhibited irregularly stacked papillary structures, small glandular structures, and fenestrated structures. The atypical cells had a nucleus with fine-granular chromatin and a granular cytoplasm, and nuclear grooves and intranuclear pseudo-inclusions were present. Hyaline globules were observed in the glandular lumens and in the background. The presumptive histological type was an adenocarcinoma, but the cytological features were different from those of an endometrioid carcinoma. A histological examination of the endometrial biopsy revealed an adenocarcinoma, and a simple hysterectomy was performed. A grayish-white elevated mass measuring 90 mm × 70 mm × 40 mm was observed on the uterine corpus in the hysterectomy specimen. Histologically, the tumor proliferated as complex tubular structures containing eosinophilic colloid-like materials and trabecular structures. The tumor cells were diffuse and positive for GATA-3 and partially positive for thyroid transcription factor-1. Estrogen and progesterone receptors were negative. An ML-EAC was diagnosed. The tumor was invasive and extended beyond one-half of the muscle layer with a high degree of vascular invasion. In conclusion, we need to focus on the various shapes of the cell aggregate, nuclear grooves, and intranuclear pseudo-inclusions of tumor cells to distinguish an ML-EAC from other endometrial carcinomas in endometrial cytology.
Topics: Humans; Female; Endometrial Neoplasms; Aged; Adenocarcinoma; Endometrium
PubMed: 38454318
DOI: 10.1002/dc.25300 -
Croatian Medical Journal Feb 2024Uterine leiomyosarcoma (uLMS) is a rare but aggressive cancer with a high metastatic potential and an unfavorable prognosis. A 54-year-old woman with a history of... (Review)
Review
Uterine leiomyosarcoma (uLMS) is a rare but aggressive cancer with a high metastatic potential and an unfavorable prognosis. A 54-year-old woman with a history of uterine fibroids clinically presented with a painless, palpable left breast mass measuring 20 mm. A core biopsy of the breast mass demonstrated a cellular spindle cell neoplasm (a potentially malignant smooth muscle neoplasm; B4). A wide local breast-mass excision was performed, revealing grade-2 leiomyosarcoma. A re-review of the uterine fibroids revealed that the largest one (200 × 130 mm), initially diagnosed as symplastic leiomyoma, was morphologically identical to the breast lesion. Additional diagnostic work-up revealed multiple liver and pulmonary metastases with a suspected metastatic sclerotic lesion in the L3 projection. The patient was subsequently treated with chemotherapy protocol for metastatic uLMS. The latest follow-up in September 2023 confirmed stable disease. This case highlights the importance of considering unusual metastatic patterns when evaluating breast masses, particularly in patients with a history of non-specific uterine conditions. Comprehensive diagnostic work-up, including imaging and histopathologic examinations, is crucial for an accurate diagnosis of uLMS and appropriate treatment selection. Further studies are needed to better understand the underlying mechanisms and optimal management strategies for metastatic uLMS.
Topics: Female; Humans; Middle Aged; Leiomyosarcoma; Leiomyoma; Antineoplastic Combined Chemotherapy Protocols; Liver; Lung Neoplasms
PubMed: 38433512
DOI: 10.3325/cmj.2024.65.51 -
Modern Pathology : An Official Journal... Apr 2024Atypical spindle cell/pleomorphic lipomatous tumor (ASPLT) is a recently described adipocytic tumor predominantly affecting the subcutaneous soft tissues of adults....
Atypical spindle cell/pleomorphic lipomatous tumor (ASPLT) is a recently described adipocytic tumor predominantly affecting the subcutaneous soft tissues of adults. Previous studies have shown that ASPLT follows a benign clinical course with a 4% to 12% local recurrence rate and no risk of dedifferentiation. Herein, we describe the clinicopathologic and molecular findings of 4 cases of ASPLT showing unequivocal sarcomatous transformation. Three patients were male and one was female, aged 65, 70, 74, and 78 years. Two cases presented as mass-forming lesions, while 1 case was incidentally discovered. The tumors measured 30, 55, 80, and 110 mm and occurred in the chest wall (n = 2) or arm (n = 2); all were subcutaneous. Microscopically, they showed a biphasic appearance comprising a low-grade ASPLT component and a high-grade sarcomatous component. The low-grade components showed features in the spectrum of either atypical pleomorphic lipomatous tumor (n = 2) or atypical spindle cell lipomatous tumor (n = 2). The high-grade components displayed leiomyosarcoma-like (n = 2), pleomorphic liposarcoma-like (n = 1) or undifferentiated sarcoma-like (n = 1) morphology. On immunohistochemistry, tumors were negative for MDM2 and showed loss of RB1 expression. In addition, the leiomyosarcoma-like areas seen in 2 cases were positive for smooth muscle actin and H-caldesmon. Single-nucleotide polymorphism array, performed in 3 cases, showed deletions of TP53, RB1, and flanking genes in both components. In contrast, the sarcomatous components showed more complex genomic profiles with rare segmental gains and recurrent loss of PTEN (n = 3), ATM (n = 2), and CDKN2A/B (n = 2) among other genes. Whole exome sequencing identified a TP53 variant in one case and an ATRX variant in another, each occurring in both tumor components. Limited clinical follow-up showed no recurrence or metastasis after 1 to 13 months (median, 7.5 months) postsurgical excision. Altogether, our data support that ASPLT can rarely develop sarcomatous transformation and offer insights into the molecular mechanisms underlying this event.
Topics: Adult; Humans; Male; Female; Leiomyosarcoma; Biomarkers, Tumor; Liposarcoma; Sarcoma; Lipoma; Soft Tissue Neoplasms
PubMed: 38417627
DOI: 10.1016/j.modpat.2024.100454