α-Fetoprotein (AFP)-producing gastric carcinoma (GC) (AFPGC) is a special subtype of GC that is clinically characterized by a high incidence of liver metastasis and poor prognosis. The present study reported the case of a patient with AFPGC who showed complete response (CR) after stereotactic body radiotherapy (SBRT) for liver metastasis. A 76-year-old male patient underwent total gastrectomy with D2 lymph node dissection for GC. The excised tumor was diagnosed as AFPGC due to the patient\'s high serum AFP level (3,763 ng/ml) and AFP expression on immunohistochemistry. The patient was diagnosed with liver metastasis two months after the surgery. 18F-fluorodeoxyglucose positron emission tomography indicated that the metastasis was a single recurrent focus. Although the patient underwent seven cycles of chemotherapy with S-1-based regimens, the metastatic tumor showed only a minor response despite the decrease in serum AFP levels. To realize high-quality disease control, SBRT was performed on the liver tumor (total dose of 48 Gy in four fractions). The metastasis showed a significant response two weeks after the completion of SBRT and CR two years later. CR was sustained and the patient survived with no evidence of recurrence 62 months after the diagnosis of liver metastasis. Literature data on the efficacy of radiotherapy for liver metastasis from AFPGC remain scarce. The present case report suggests that SBRT has high efficacy for oligometastatic diseases and may be included as an indication for the treatment of liver metastasis from AFPGC.

A vaginal yolk sac tumor (YST) is a rare malignant germ cell tumor for infants and children, and it has been >50 years since the first case was reported. The treatment strategy has changed markedly in the past 50 years, from radical surgical treatment to conservative surgery combined with chemotherapy, and then to combined chemotherapy alone. The present study reports the case of a primary vaginal YST in a 13-month-old girl that was successfully treated by tumor resection combined with chemotherapy. The clinical symptoms, imaging features and treatment characteristics are described in detail, as well as the postoperative treatment. There was no local recurrence or metastasis for the 2 years of follow-up to date. A literature review was also conducted to investigate the clinicopathological features, treatment and prognosis of this tumor. Overall, surgery combined with bleomycin, etoposide and carboplatin combination chemotherapy can be an effective option for vaginal YST.

The existence of tumor heterogeneity is widely recognized; however, heterogeneity of the antitumor response in multiple tumor nodules in the same patient has not been reported. Sintilimab, a monoclonal antiprogrammed cell death receptor-1 (PD-1) antibody, was used to treat patients with unresectable hepatocellular carcinoma (HCC). In the present study, we report a case of therapeutic heterogeneity in relapsed HCC with lung metastases. A 57-year-old female patient was diagnosed with HCC and underwent radical hepatectomy. One and a half years later, imaging scans found multiple metastatic tumors in the lung, which were accompanied by an increased α-fetoprotein (AFP) level. The patient then started to receive sintilimab. In the first 6 months after sintilimab treatment, all the metastatic nodules regressed gradually and ultimately disappeared, except for one nodule, which remained stable in the following 3 months. Finally, the patient underwent pulmonary lobectomy to remove the remaining nodule. Thereafter, follow-up visits showed the AFP level decreased to normal and imaging scans showed no signs of recurrence, confirming that the patient exhibited a clinically complete response. Pathological assessments showed that in the primary tumor site, the tumor comprised moderately differentiated HCC with a few infiltrated cytotoxic T cells and negative PD-L1 expression. While in the metastatic site, the nodule was composed of poorly differentiated HCC with cytotoxic T-cell infiltration with few cells inside the tumor and expressed PD-L1 in some areas of the tumor. There were dynamic alterations of PD-L1 expression and cytotoxic T-cell infiltration in the primary and relapsed HCC lesions after anti-PD-1 treatment. This case presented the heterogeneities of both the tumor microenvironment and the following antitumor response among the metastatic nodules in the same patient and revealed the importance of comprehensive therapy in cancer treatment.

Germ cell tumors (GCTs) often occur in male testes and female ovaries. Extragonadal GCTs account for approximately 2% to 5% of all GCTs and mainly occur in the mediastinum, retroperitoneum, and pineal gland. In this study, we reported a rare case of gastric adenocarcinoma with GCT components. The patient\'s serum α-fetoprotein (AFP) level was higher than normal. Abdominal computed tomography (CT) showed a 10-cm × 10-cm tumor between the spleen and the bottom of the stomach. Gastric endoscopy indicated an ulcerative lesion extending from the bottom of the stomach to the antrum. Tissue biopsy identified the tumor as an adenocarcinoma. The patient underwent abdominal tumor resection, subtotal gastrectomy, D2 lymphadenectomy, and splenectomy. Postoperative histopathology showed that the tumor was a moderately to poorly differentiated adenocarcinoma. Immunohistochemistry analysis revealed positive staining for AFP, glypican-3, and placental alkaline phosphatase. Gastric adenocarcinoma with GCT components is particularly uncommon and rarely reported. Elevated serum AFP and/or β-human chorionic gonadotropin levels, abdominal CT, histopathology, and immunohistochemistry may help diagnose GCTs. Radical surgery resection is the primary treatment method for GCTs. Adjuvant chemotherapy and radiotherapy are effective for advanced GCTs.

α-fetoprotein (AFP)-secreting gastric cancer (AFP-GC) is a relatively rare, aggressive malignancy among all GC types. However, no GC case with simultaneous expression of AFP and epidermal growth factor receptor 2 (HER2) has been reported to date. To the best of our knowledge, the present report was the first to describe the use of apatinib to treat a patient with advanced GC characterized by AFP-secretion and HER2-positivity. An 86-year-old man with advanced GC was diagnosed with AFP-secretive and HER2-positive GC with liver metastasis at The Affiliated Hospital of Jiujiang University (Jiujiang, China). The patient received first-line (i.e., S-1 plus oxaliplatin) and second-line (i.e., docetaxel) chemotherapy combined with trastuzumab for two cycles, respectively. However, the disease progressed rapidly. Subsequently, apatinib was administered as third-line therapy. After two cycles of apatinib therapy, the patient reported the disappearance of upper abdominal pain and an improvement in his appetite. Furthermore, the AFP level had sharply decreased to 620 ng/ml. Subsequently, upper abdominal computed tomography imaging revealed that the gastric lesion and liver metastatic lesion had reduced in size by 67% and 24%, respectively, suggesting partial remission. Currently, the patient has continued to receive apatinib therapy. It was speculated that AFP-secretion status could contribute to the chemoresistance of HER2-positive GC. Apatinib may be a promising anticancer agent in the case of advanced AFP-producing and HER2-positive GC.

Hepatoid thymic carcinoma is an extremely rare subtype of primary thymus tumor resembling \"pure\" hepatoid adenocarcinomas with hepatocyte paraffin 1 (Hep-Par-1) expression. A 53-year-old man presented with voice change and a neck mass. Multiple masses involving the thyroid, cervical and mediastinal lymph nodes, and lung were detected on computed tomography. Papillary thyroid carcinoma was confirmed by biopsy, and the patient underwent neoadjuvant chemoradiation therapy. However, the anterior mediastinal mass was enlarged after the treatment whereas the multiple masses in the thyroid and neck decreased in size. Microscopically, polygonal tumor cells formed solid sheets or trabeculae resembling hepatocytes and infiltrated remnant thymus. The tumor cells showed immunopositivity for cytokeratin 7, cytokeratin 19, and Hep-Par-1 and negativity for α-fetoprotein. Possibilities of germ cell tumor, squamous cell carcinoma, and metastasis of thyroid papillary carcinoma were excluded by immunohistochemistry. This report on the new subtype of thymic carcinoma is the third in English literature thus far.

Large cell neuroendocrine carcinoma (LCNEC) is a rare and aggressive cancer that typically presents in the lung. The current case report describes a 56 year old male who presented to Strong Memorial Hospital with progressive dyspnea and was revealed to have a large anterior mediastinal tumor with metastases to axillary, hilar and mediastinal lymph nodes. Tumor marker results revealed an elevated plasma level of α-fetoprotein (AFP), which initially pointed towards a diagnosis of teratoma, but the tumor stained positive for neuroendocrine markers CD56, chromogranin, and synaptophysin on biopsy, consistent with LCNEC. AFP-positive tumor cells were identified, and no alternate cause for the elevated AFP was identified. The patient underwent genetic testing revealing the tumor to be ALK, ROS1, KRAS, BRAF and EGFR wild type. The patient received 6 cycles of chemotherapy with cisplatin (80 mg/m2) and etoposide (100 mg/m2) and then radiation with an initial minor response. The patients course was complicated by the development of superior vena cava syndrome requiring emergency stenting. The results of the current case suggest that AFP may be worthy of further exploration as a potential tumor marker in LCNEC.

A 60-year-old male patient presented with a serum α-fetoprotein (AFP) level of 2940.5 ng/mL accompanied by a significant increase in serum globulin. Hepatitis B virus (HBV) DNA was 2.85 × 103 (normal value <1.0 × 103). B-mode ultrasound and magnetic resonance imaging showed characteristic manifestations and he was clinically diagnosed with hepatocellular carcinoma in January 2015. He received radiofrequency ablation and tenofovir disoproxil anti-HBV therapy and his serum AFP and globulin levels were significantly reduced. In March 2018, he presented at our Hematology Department with fatigue and a pale complexion. At that time, his serum AFP level was normal, with hemoglobin 61 g/L and globulin 64.7 g/L. He was diagnosed with multiple myeloma (MM) by bone marrow examination, and immunofixation electrophoresis. The patient received PCD chemotherapy (bortezomib 2.0 g/dL on days 1, 4, 8, and 11 plus cyclophosphamide 0.3 g/dL on days 1-4 plus dexamethasone 20 mg/dL on days 1-2, 4-5, 8-9, and 11-12). The patient finally died of MM complicated by disseminated intravascular coagulation.

Liver cancer is a common malignant disease in China, while the primary hepatic neuroendocrine tumor (PHNET) is extremely rare presented with various manifestations. We herein describe an interesting PHNET case, which was clinically diagnosed as hepatocellular carcinoma (HCC) based on strong clinical evidence and the national guideline, but confirmed to be PHNET by pathology. A42-year-old Chinese male was admitted for persistent upper abdominal pain, and CT scan revealed a huge liver tumor in the left lobe. The tumor presented attributes of tumor rupture, portal vein tumor thrombus, elevated serum AFP level, background hepatitis B virus infection history, and radiological features mimicking typical HCC. After left semi-hepatectomy was performed for curative treatment of the primary \"HCC\", the pathology demonstrated the correct diagnosis be poorly differentiated neuroendocrine carcinoma (NEC). The immunohistochemistry assays showed positive neuroendocrine markers of CgA and Syn and negative HCC markers of Hep Par 1 and GPC3, ruling out concurrent HCC. This case and literature review suggest that in spite of rare incidence, PHNET should be considered as a possible diagnosis when lacking a confirmative pathology result, even when sufficient evidence of typical presentation exist to establish the clinical diagnosis of HCC.

Hepatoid adenocarcinoma of lung (HAL) is a rare and aggressive tumor. The current study reported a new HAL case in the right lower lung with high serum α-fetoprotein (AFP) level in a 71-year-old male patient. After the confirmation of morphology and immunohistochemistry, the patient was diagnosed clinically with HAL and treated with radio-frequency ablation. However, the patient whose disease progressed eventually died 4 months after diagnosis. Whole genome sequencing analysis identified a driver gene mutation in the FAT atypical cadherin 1 gene (FAT1) and the copy number loss. The tumor was microsatellite-stable and tumor mutation burden (TMB) was 1.69 mutations/Mb. PD-L1 expression was negative by IHC. Our finding provide further clues for the molecular basis of HAL and the efficacy of immunotherapy needs to be explored.