Abstract Ectopic hepatocellular carcinoma (EHCC) is an extremely rare neoplasm, especially in the mediastinum, which shares morphologic characteristics with intrahepatic hepatocellular carcinoma (HCC). Its clinical features remain unclear, posing significant diagnostic and therapeutic challenges. The prognosis is also unclear due to its rarity and potential variability. This study reports the first case of EHCC in the mediastinum with subsequent brain metastasis. A 50-year-old man presented with shoulder and chest discomfort persisting for 5 months, accompanied by progressive weight loss and fatigue over the preceding 2 years. Imaging showed a mediastinal mass initially suspected to be lymphoma due to its malignant characteristics. However, histopathological examination identified the lesion as HCC, supported by characteristic immunohistochemical markers, despite normal abdominal imaging. Two months later, the tumor progressed despite intensive radiotherapy, and the patient experienced recurrent seizures. Subsequent brain imaging confirmed multiple intracranial metastases. Unfortunately, the patient died 6 months after diagnosis. The ectopic liver is more susceptible to hepatocarcinogenesis than the main liver; this is attributed to its incomplete functional structure. EHCC can be considered as differential diagnosis of mediastinal masses, even when no intrahepatic HCC is found. The rarity of EHCC in the mediastinum poses difficulties in developing treatment protocols. This case emphasizes the diagnostic challenges and aggressive nature of ectopic HCC and the need for comprehensive management strategies. There are currently no definite guidelines regarding the diagnosis, treatment, and prognosis of EHCC.
ectopic hepatocellular carcinoma ; mediastinum ; metastasis

Humans ; Artificial Intelligence ; Lung Neoplasms/pathology* ; Mediastinum/pathology* ; Lymph Nodes/pathology* ; Neoplasm Staging ; Lymph Node Excision

This article reports a case of primary thyroid diffuse large B-cell lymphoma involving the superior mediastinum with Hashimoto's thyroiditis admitted to the Department of Otolaryngology and Head and Neck Surgery, First Hospital of Jilin University. This patient underwent right thyroid lobectomy and was transferred to the Department of Hematology of the Oncology Center for 6 courses of chemotherapy with R-CHOP protocol. The postoperative recovery was good, and the patient was regularly followed up for 12 months after the operation. The patient's condition was stable, and CT showed no abnormally high metabolism in the operation area indicating the inhibition of tumor activity, superficial lymph nodes and peripheral blood cells were normal. The case encountered many difficulties in the diagnosis process, and the diagnosis was not confirmed after puncture in two Grade III Class A hospitals in China. There are few patients with primary thyroid diffuse large B-cell lymphoma complicated with Hashimoto's thyroiditis, and it is particularly rare to invade the mediastinum. There is no report in China and abroad in the literature we reviewed. Therefore, this article reports the case and retrospectively analyzes the etiology, clinical symptoms, diagnosis and treatment of primary thyroid lymphoma.
Humans ; Mediastinum ; Retrospective Studies ; Hashimoto Disease ; Lymphoma, Large B-Cell, Diffuse ; Thyroid Neoplasms

Esophageal Perforation/etiology* ; Esophagus ; Foreign Bodies/complications* ; Humans ; Magnetic Phenomena ; Mediastinum

Hematologic Diseases ; Hematopoiesis, Extramedullary ; Humans ; Mediastinal Neoplasms/surgery* ; Mediastinum ; Tomography, X-Ray Computed

Child ; Humans ; Mediastinum ; Myoepithelioma/diagnosis*

OBJECTIVE: To validate the value of dual energy CT (DECT) in the differentiation of mediastinal metastatic lymph nodes from non-metastatic lymph nodes in non-small cell lung cancer (NSCLC). METHODS: In the study, 57 surgically confirmed NSCLC patients who underwent enhanced DECT scan within 2 weeks before operation were enrolled. Two radiologists analyzed the CT images before operation. All mediastinal lymph nodes with short diameter≥5 mm on axial images were included in this study. The morphological parameters [long-axis diameter (L), short-axis diameter (S) and S/L of lymph nodes] and the DECT parameters [iodine concentration (IC), normalized iodine concentration (NIC), slope of spectral hounsfield unit curve (λHU) and effective atomic number (Zeff) in arterial and venous phase] were measured. The differences of morphological parameters and DECT parameters between metastatic and non-metastatic lymph nodes were compared. The parameters with significant difference were analyzed by the Logistic regression model, then a new predictive variable was established. Receiver operator characteristic (ROC) analyses were performed for S, NIC in venous phase and the new predictive variable. RESULTS: In 57 patients, 49 metastatic lymph nodes and 938 non-metastatic lymph nodes were confirmed by surgical pathology. A total of 163 mediastinal lymph nodes (49 metastatic, 114 non-metastatic) with S≥5 mm were detected on axial CT images. The S, L and S/L of metastatic lymph nodes were significantly higher than those of non-metastatic lymph nodes (P < 0.05). The DECT parameters of metastatic lymph nodes were significantly lower than those of non-metastatic lymph nodes (P < 0.05). The best single morphological parameter for differentiation between metastatic and nonmetastatic lymph nodes was S (AUC, 0.752; threshold, 8.5 mm; sensitivity, 67.4%; specificity, 73.7%; accuracy, 71.8%). The best single DECT parameter for differentiation between metastatic and nonmetastatic lymph nodes was NIC in venous phase (AUC, 0.861; threshold, 0.53; sensitivity, 95.9%; specificity, 70.2%; accuracy, 77.9%). Multivariate analysis showed that S and NIC were independent predictors of lymph node metastasis. The AUC of combined S and NIC in the venous phase was 0.895(sensitivity, 79.6%; specificity, 87.7%; accuracy, 85.3%), which were significantly higher than that of S (P < 0.001) and NIC (P=0.037). CONCLUSIONS The ability of quantitative DECT parameters to distinguish mediastinal lymph node metastasis in NSCLC patients is better than that of morphological parameters. Combined S and NIC in venous phase can be used to improve preoperative diagnostic accuracy of metastatic lymph nodes.
Carcinoma, Non-Small-Cell Lung/diagnostic imaging* ; Humans ; Lung Neoplasms/diagnostic imaging* ; Lymph Nodes ; Lymphatic Metastasis ; Mediastinum ; Tomography, X-Ray Computed

OBJECTIVE: Primary mediastinal yolk sac tumor, which is also known as endodermal sinus tumor, is a rare but lethal neoplasm and its prognosis is very dismal. The current treatment for this tumor is controversial, and chemotherapy combined with resection of residual lesions is adopted sometimes. We summarized the experience of seven primary mediastinal yolk sac tumors treated with platinum-based chemotherapy and extended resection in Peking University First Hospital. METHODS: Clinicopathological data of the patients with primary mediastinal yolk sac tumor who received operation in Peking University First Hospital between August 2014 and August 2018 were collected and analyzed retrospectively. RESULTS: We experienced seven primary mediastinal yolk sac tumors during this period. Computed tomography scan revealed an anterior mediastinal tumor in all the patients and all of them had markedly raised alphafetoprotein (AFP) and normal β-human chorion gonadotropin (β-HCG). Five patients underwent needle core biopsy before treatment, which showed a mediastinal yolk sac tumor. All of these patients received preoperative platinum-based chemotherapy and they all presented partial response according to computed tomography. Two other patients did not receive preoperative biopsy, so they directly underwent extended resection. All of the seven patients underwent operation successfully and two of them experienced postoperative complications, including one with pneumonia and the other with atelectasis. R0 resection was achieved in six patients and R1 resection was achieved in the other patient. According to postoperative pathology, there were one microcyst subtype, one adenoid subtye, one giant capsule subtype and two hybrid subtypes. Surprisingly, there were no yolk sac tumor tissue in the other two patients after preoperative chemotherapy. All the patients received postoperative chemotherapy, excluded one patient who was unable to tolerate chemotherapy after operation. Three patients experienced postoperative pulmonary metastases within one year and two of them died soon. The other patient received chemotherapy and immunotherapy after recurrence and he was alive at the time of writing. Four other patients were alive without recurrence and metastasis. CONCLUSION Primary mediastinal yolk sac tumor is rare and its prognosis is poor. A multimodality approach including adjuvant chemotherapy and resection of residual lesions is the optimal treatment and it may lead to long-term survival.
Endodermal Sinus Tumor ; Humans ; Male ; Mediastinal Neoplasms ; Mediastinum ; Neoplasm Recurrence, Local ; Retrospective Studies

A 68-year-old woman presented with weight loss of 7 kg over two years. Clinical examination revealed no specific abnormality and the patient was otherwise asymptomatic. Chest radiography performed to screen for malignancy revealed a soft tissue opacity projected over the mediastinum. Computed tomography of the thorax showed an enhancing anterior mediastinal mass with heterogeneous enhancement and contrast pooling in the arterial phase, followed by homogeneous enhancement in the venous phase, consistent with an aneurysm arising from the superior vena cava. This case highlights superior vena cava aneurysms as extremely rare causes of anterior mediastinal masses. Other causes of anterior mediastinal masses were also discussed.
Aged ; Aneurysm ; diagnostic imaging ; Female ; Humans ; Mediastinum ; diagnostic imaging ; Radiography, Thoracic ; Tomography, X-Ray Computed ; Vena Cava, Superior ; diagnostic imaging

Yolk sac tumors are rare malignant germ cell neoplasms that usually arise from the gonads. Extragonadal yolk sac tumors (EGYSTs) frequently occur in the mediastinum in post-pubertal females. EGYSTs in the pelvis are extremely rare, and to date, only thirteen cases have been reported in the English literature. Among them, the primary EGYST of the pelvic peritoneum in post-pubertal females has only been reported in ten cases. The present case describes a 26-year-old female diagnosed with primary peritoneal yolk sac tumor located in the rectouterine pouch. We report clinical and tumor imaging features, including ultrasound, computed tomography (CT), magnetic resonance images (MRI), positron emission tomography-computed tomography (PET-CT), and present a review of the literature.
Adult ; Douglas' Pouch ; Electrons ; Endodermal Sinus Tumor ; Female ; Gonads ; Humans ; Magnetic Resonance Imaging ; Mediastinum ; Neoplasms, Germ Cell and Embryonal ; Pelvis ; Peritoneum ; Ultrasonography ; Yolk Sac