Rapidly developing intrathoracic low-grade fibromyxoid sarcoma: A case report.

Low-grade fibromyxoid sarcoma (LGFMS) is a rare mesenchymal tumor that primarily arises in the limbs and trunk of young adults, and rarely in the thoracic cavity. An 84-year-old Japanese woman presented with a right intrathoracic mass which was 8 cm in size. CT-guided needle biopsy did not provide a definitive diagnosis. Perioperatively, a mass was found in the right lower lobe of the lung and was suspected to have invaded the chest wall at the sixth-eighth ribs. A right lower lobectomy and combined chest wall resection were performed. Microscopic examination revealed that the tumor was a low-grade spindle cell tumor originating from the pleura demonstrating focal invasion of the lung. The tumor exhibited positivity for MUC4, and FUS gene translocation was confirmed through fluorescence in situ hybridization. Unfortunately, 10 months postoperatively, tumor recurrence was noted as peritoneal dissemination, and the patient passed away 13 months postoperatively. Although LGFMS may be diagnosed histologically as a low-grade tumor by needle biopsy, in this case, it was highly malignant. Postoperative long-term regular medical follow-up is recommended considering the highly malignant nature of the tumor and the high risk of local recurrence and pulmonary metastasis.

A case of pulmonary pleomorphic carcinoma associated with cystic airspace.

Lung cancer associated with a cystic airspace is frequently misdiagnosed or overlooked. Adenocarcinoma, followed by squamous cell carcinoma, is the most typical histologic type of lung cancer connected to a cystic airspace. Here we present the rare case of lung pleomorphic carcinoma associated with a cystic airspace. We encountered a 74-year-old Japanese man diagnosed by computed tomography (CT) as having a nodule outside a cystic airspace in the lung. Several previous CT images showed that the cystic airspace preceded the nodule. Postsurgery, pathology indicated a diagnosis of pleomorphic carcinoma. Since pulmonary pleomorphic carcinomas pursue an aggressive clinical course, their early detection may contribute to an improved prognosis. Our case demonstrated that pleomorphic carcinoma can arise with cystic airspaces. For early diagnosis of those aggressive lung cancers, chest physicians should carefully examine the walls of cystic airspaces on CT.

Primary adrenal Ewing's sarcoma family of tumors with tumor thrombus of the inferior vena cava: a case report.

BACKGROUND: Ewing's sarcoma is a malignant neoplasm that mainly occurs in skeletal tissue but can rarely arise in soft tissues. Recently, small round cell tumors (including Ewing's sarcoma) caused by chromosomal translocations have been collectively termed Ewing's sarcoma family of tumors. We report a rare case of primary adrenal Ewing's sarcoma family of tumors with tumor thrombus. CASE PRESENTATION: A 22-year-old Asian woman was referred to our hospital with a left retroperitoneal tumor 19 cm in diameter. Tumor thrombus was identified from the left adrenal vein to the inferior vena cava, infiltrating the right atrium. Total tumor excision with left adrenalectomy, nephrectomy, and thrombectomy was performed under hypothermic circulatory arrest, followed by seven courses of adjuvant chemotherapy. The patient has shown no signs of recurrence as of 26 months postoperatively. CONCLUSION: Radical surgery combined with systemic chemotherapy may contribute to good prognosis in patients with primary adrenal Ewing's sarcoma family of tumors.

Allergic Bronchopulmonary Mycosis Complicated with Lung Adenocarcinoma.

Chest computed tomography (CT) of a 76-year-old woman with bronchial asthma showed multiple lung nodules with high CT densities that were compatible with high-attenuation mucoid (HAM) impactions characteristic of allergic bronchopulmonary mycosis (ABPM). Follow-up chest CT revealed increased sizes of multiple lung nodules. However, a left upper lobe nodule showed lower CT density than the other HAM impactions. A transbronchial lung biopsy of that upper lobe nodule revealed lung adenocarcinoma. Measuring the CT density is important for the differential diagnosis of lung nodules when following ABPM patients. Our patient's increased serum carcinoembryonic antigen levels were associated with peripheral blood eosinophilia. Mucoid impaction in the lung was positively stained with carcinoembryonic antigen and showed the distribution of eosinophilic granules.

Successful conversion surgery after FOLFIRINOX therapy in a patient with advanced pancreatic acinar cell carcinoma with a solitary peritoneal dissemination: A case report.

BACKGROUND: Pancreatic acinar cell carcinoma is rare; it accounts for 1% of all malignant pancreatic exocrine tumors. Although surgical resection is an option for curative treatment, the safety and efficacy of conversion surgery in patients with pancreatic acinar cell carcinoma with metastasis remain unknown. CASE: A 67-year-old man with epigastric pain and a pancreatic tumor was referred to our hospital. Computed tomography revealed a large tumor with a maximum diameter of 67 mm at the pancreatic head and a 23-mm mass in the left upper abdominal cavity. Because a definitive diagnosis could not be made based on endoscopic ultrasonography-guided fine needle aspiration biopsy findings, a diagnostic laparoscopy was performed. The tumor in the greater omentum at the left upper abdomen, resected under laparoscopy, was histopathologically diagnosed as pancreatic acinar cell carcinoma. Therefore, the pancreatic tumor was diagnosed as an unresectable pancreatic acinar cell carcinoma with a solitary peritoneal dissemination. The size of the main pancreatic tumor decreased to 15 mm after 18 courses of FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan, and oxaliplatin). Subsequently, the patient underwent conversion surgery, and the initial diagnosis of pancreatic acinar cell carcinoma was confirmed on pathological examination. The patient was discharged 31 days postoperatively, following which he received adjuvant chemotherapy with S-1. No sign of recurrence has been observed for 32 months after surgical resection. CONCLUSION: FOLFIRINOX may be effective in patients with pancreatic acinar cell carcinoma, and conversion surgery after FOLFIRINOX may be applicable to selective patients.

Systemic Abscopal Effect of Low-dose Radiotherapy (2 Gy ×2) against Palatine Tonsil Follicular Lymphoma.

A 52-year-old man presented with palatine tonsillar swelling caused by follicular lymphoma. His tumor burden was low, but exacerbation of snoring and dysphagia was observed. Considering the first wave of coronavirus disease 2019 (COVID-19) pandemic, he received palliative 4-Gy irradiation to the tonsils in 2 fractions, which induced partial regression of tonsillar swellings and eradication of the circulating lymphoma cells. We suggest that low-dose radiotherapy triggered an abscopal effect of lymphoma, which allowed the patient time to receive COVID-19 vaccination before starting immunosuppressive chemo-immunotherapy.

Glucocorticoid-induced redistribution lymphocytosis in mantle cell lymphoma with hyaline vascular Castleman disease-like features.

We report a case of mantle cell lymphoma mimicking Castleman disease. A 76-year-old man presented with generalized lymphadenopathy, splenomegaly, anemia, polyclonal gammopathy, and pulmonary infiltrations. Lymph node biopsy revealed histological features of hyaline vascular Castleman disease. Treatment with prednisolone induced lymphocytosis with immunophenotypic and genetic features of mantle cell lymphoma. A detailed immunohistochemical study of the lymph node demonstrated a mantle cell lymphoma-mantle zone growth pattern. Glucocorticoid-induced distribution lymphocytosis has not been reported in mantle cell lymphoma. Careful observation of circulating lymphocytes during steroid treatment may enable diagnosis of the underlying occult lymphoma in a subset of patients exhibiting clinical manifestations of Castleman disease.

Laryngeal malignant peripheral nerve sheath tumor mixed with high- and low-grade malignancies.

Malignant peripheral nerve sheath tumors (MPNSTs), as defined by immunohistochemical evaluation, are identified along a spectrum ranging from atypical neurofibroma to high-grade MPNST because these tumors are similar in terms of cell shape and tissue components on hematoxylin-eosin (HE) staining. The patient was a 57-year-old male referred to our hospital, with a recurrent red tumor at the anterior commissure of the larynx and submucosal swelling of the right vocal fold. A surgical specimen from a right horizontal partial laryngectomy was evaluated immunohistochemically. A high-grade MPNST lesion was included in the submucosal white tumor, whereas a low-grade MPNST lesion was encountered around the high-grade MPNST lesion. This tumor may involve different malignancies even when it is small. Although intra-tumor heterogeneity in cancers has been reported recently, careful immunohistochemical examination can be important and beneficial for eradicating the tumor while preserving vocal function.

A case of mixed tumor formed by metastasis of urothelial carcinoma and malignant lymphoma to the same lymph nodes.

INTRODUCTION: Mixed tumor in the same lymph nodes is extremely rare and no previous reports have described mixed tumor comprising urothelial carcinoma and malignant lymphoma. CASE PRESENTATION: A 71-year-old woman visited a local clinic with a main complaint of hematuria. Imaging revealed right hydronephrosis and a mid-ureter tumor shadow. Positron emission tomography-computed tomography showed high uptake of fluorodeoxyglucose in para-aortic lymph nodes. Abdominal para-aortic lymph node biopsy was performed. Pathology showed urothelial carcinoma and malignant lymphoma in the same lymph nodes, where a mixed tumor was diagnosed. CONCLUSION: We encountered a case of mixed tumor of urothelial carcinoma and Hodgkin lymphoma, which metastasized to the same tissues.

Prognostic significance of human papillomavirus 16 viral load level in patients with oropharyngeal cancer.

Human papillomavirus (HPV) infection in patients with oropharyngeal squamous cell carcinoma (OPSCC) is a major determinant for better prognosis. However, there remain HPV-positive patients who have poor outcomes. The stratification strategy for detecting high-risk patients among those with HPV-positive OPSCC has not been well delineated, especially for Asian patients. We undertook a retrospective cohort study on the survival rate of 89 Japanese patients diagnosed with primary OPSCC. The tumors were concurrently analyzed for the presence of HPV E6 DNA/mRNA, viral DNA load, p16 expression, viral physical status, and viral variant lineage. Human papillomavirus 16 viral DNA was found in 45 (51%) OPSCCs. Human papillomavirus 16 DNA-positive OPSCCs with higher viral load (classified as HPV16 DNA-medium/high OPSCCs) showed significantly favorable overall survival and progression-free survival compared with HPV16 DNA-positive OPSCCs with lower viral load (<10 copies/cell; HPV16 DNA-low OPSCCs) and HPV16 DNA-negative OPSCCs. E6 mRNA expression was observed in all HPV16 DNA-medium/high OPSCCs but not in HPV16 DNA-low OPSCCs. Notably, p16-positive and HPV16 DNA-negative/low OPSCCs showed significantly worse survival than p16-positive and HPV16 DNA-medium/high OPSCCs and resembled HPV-unrelated OPSCCs with regard to survival and risk factor profile. Although not significant, a trend toward shorter survival was observed for HPV16-integrated OPSCCs. Phylogenetic analysis revealed two major types of HPV16 variants termed Asian (A4) and European (A1/A2/A3) variants, but no difference in survival between these variants was observed. Altogether, these findings suggest that HPV viral load is a potentially informative factor for more accurate risk stratification of patients with OPSCC.

Fumarate hydratase-deficient renal cell carcinoma: A clinicopathological study of seven cases including hereditary and sporadic forms.

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) has been incorporated into the recent international histological classification of renal tumors. However, to date, there are limited studies describing the clinicopathological features of fumarate hydratase (FH)-deficient RCC, including the hereditary (HLRCC) and sporadic forms. Herein, we present a clinicopathological study of seven cases with FH-deficient RCC. The age of patients ranged from 26 to 70 years with mean and median age of 51.7 and 57 years, respectively. The follow-up data of all patients were available. One patient was alive without the disease and five patients were alive with active disease. One patient died of the disease. Family history of RCC, or skin or uterine smooth muscle tumor within second degree of kinship was present in four of seven patients. Metastasis was observed in all tumors. Metastatic sites included bone, lungs, liver, peritoneum, ovaries, tonsils, or lymph nodes. Grossly, the cut surface of the tumor usually showed light brown, brown, or whitish color. Microscopically, the cytoplasm of the tumor cells was predominantly eosinophilic and all tumors displayed various architectural patterns such as papillary, tubular, solid, or microcystic patterns. Furthermore, two tumors demonstrated a tubulocystic pattern. Sarcomatoid change and rhabdoid features were seen in five tumors and two tumors, respectively. Large cytomegaloviral (CMV) inclusion-like eosinophilic nucleoli surrounded by a clear halo were identified in all tumors. All tumors showed negative immunohistochemical reaction for FH protein. False positive results of TFE3 protein were observed in three tumors. Furthermore, a germline mutation of FH gene was identified in one patient with family history of the disease. In conclusion, FH-deficient RCC includes hereditary and sporadic forms. Grossly, this tumor is solitary and occurs unilaterally. Histologically, the tumor is characterized by various patterns such as papillary, tubular, solid, tubulocystic, or microcystic, has eosinophilic cytoplasm and CMV-like high-grade nuclei. FH-deficient RCCs frequently metastasize to other anatomic sites. TFE immunoreactivity may occur in some FH-deficient RCCs, and immunohistochemistry can accurately diagnose these tumors and mutational analysis of FH gene.

A case of spontaneous mesenteric hematoma with diagnostic difficulty.

BACKGROUND: Spontaneous mesenteric hematoma (SMH) is a rare condition characterized by intraperitoneal hemorrhage of unknown etiology. SMH without worsening of general status allows conservative management; however, patients showing chronological changes on imaging require surgical intervention to rule out possible malignancy. CASE PRESENTATION: A 69-year-old man was referred to our hospital to evaluate an abdominal mass with no associated clinical symptoms. He had a history of chronic hepatitis C and diabetes mellitus. Six months earlier, computed tomography (CT) revealed a 75-mm tumor arising from the jejunum, suspected to be a gastrointestinal stromal tumor (GIST) of the small intestine. Following a further 6 months of observation, the patient was referred to our hospital. Abdominal contrast-enhanced CT revealed a well-defined heterogeneous round tumor with a maximum diameter of 75 mm adjacent to the upper jejunum. The tumor was accompanied by calcification at the periphery, with no evidence of augmentation over the prior 6 months. Diffuse lymphadenopathy was observed around the aorta and splenic artery. Under the diagnosis of GIST arising from small intestine, the patient underwent elective surgery. The resection revealed an elastic soft tumor at the mesentery adjacent to the upper jejunum with severe adhesion between the tumor and jejunum. The tumor origin was unclear; thus, we performed mesenteric excision and partial enterectomy without lymph node dissection. The tumor was surrounded by fibrous capsular tissue containing massive hemosiderin deposits and cholesterol crystals showing partial calcification, resulting in a diagnosis of spontaneous hematoma of the mesentery. CONCLUSIONS: We report a case of SMH mimicking small intestinal GIST. It is difficult to diagnose long-established SMH because its radiological features change with time, and more case reports are needed to improve the accuracy of diagnosis.

Intrahepatic bile duct adenoma in a patient with gastric cancer.

We report a case of intrahepatic bile duct adenoma (BDA) detected during laparoscopic distal gastrectomy for gastric cancer. A 70-year-old man was referred to our hospital for the treatment of gastric cancer. Esophagogastroduodenoscopy revealed an irregular, nodular, and elevated lesion on the greater curvature side of the middle third of the stomach. Abdominal contrast-enhanced computed tomography showed wall thickening with homogeneous enhancement in the middle part of the stomach, and no lesions in the liver. The patient underwent laparoscopic distal gastrectomy with regional lymphadenectomy, and during the operation a small whitish nodule was observed on the lateral segment of the liver surface. The lesion was excised by partial resection of the liver for the purpose of both histological diagnosis and treatment. Pathological examination of the liver lesion revealed no structural or cellular atypia, no stromal invasion, and immunohistochemical positivity for CK7 and CK19, but negativity for p53. The final diagnosis was well-differentiated adenocarcinoma invading the gastric serosal layer without lymph node metastasis, and intrahepatic BDA measuring 0.4 × 0.3 cm. Following surgery, the patient remained symptom-free without evidence of recurrence for 5 months. To the best of our knowledge, this is the first case of BDA with gastric cancer. Because it is difficult to distinguish BDA from other liver tumors including metastatic cancer due to its characteristically small size and lack of specific morphological features on standard imaging, surgical resection should be considered as the most suitable approach for both accurate diagnosis and treatment.

Multiple coronary and cerebral aneurysms in a patient with chronic thromboangiitis.

A 73-year-old man had multiple coronary aneurysms that resulted in acute myocardial infarction on the day before surgery for cerebral aneurysms. Emergent coronary angiography revealed that the lesion that caused the myocardial infarction was a distal left circumflex artery, and two huge coronary aneurysms were also found in the left circumflex artery. A two-stage treatment strategy was planned, including coronary aneurysm surgery, followed by cerebral aneurysm surgery. He underwent coronary artery aneurysmorrhaphy with closure of the ostia of the afferent and efferent arteries, and coronary artery bypass grafting with a saphenous vein graft applied to the left circumflex artery. The pathological findings suggested chronic thromboangiitis, as the inflammatory cells were observed to have infiltrated the coronary artery wall. The tissue remodeling of the aneurysmal wall indicated a positive response to tenascin C. We report a case of multiple coronary aneurysms, focusing on the pathological findings. .

Merkel cell polyomavirus and Langerhans cell neoplasm.

BACKGROUND: The relationship between various external agents such as pollen, food, and infectious agents and human sensitivity exists and is variable depending upon individual's health conditions. For example, we believe that the pathogenetic potential of the Merkel cell polyomavirus (MCPyV), the resident virus in skin, is variable and depends from the degree of individual's reactivity. MCPyV as well as Epstein-Barr virus, which are normally connected with humans under the form of subclinical infection, are thought to be involved at various degrees in several neoplastic and inflammatory diseases. In this review, we cover two types of Langerhans cell neoplasms, the Langerhans cell sarcoma (LCS) and Langerhans cell histiocytosis (LCH), represented as either neoplastic or inflammatory diseases caused by MCPyV. METHODS: We meta-analyzed both our previous analyses, composed of quantitative PCR for MCPyV-DNA, proteomics, immunohistochemistry which construct IL-17 endocrine model and interleukin-1 (IL-1) activation loop model, and other groups' data. RESULTS: We have shown that there were subgroups associated with the MCPyV as a causal agent in these two different neoplasms. Comparatively, LCS, distinct from the LCH, is a neoplastic lesion (or sarcoma) without presence of inflammatory granuloma frequently observed in the elderly. LCH is a proliferative disease of Langerhans-like abnormal cells which carry mutations of genes involved in the RAS/MAPK signaling pathway. We found that MCPyV may be involved in the development of LCH. CONCLUSION: We hypothesized that a subgroup of LCS developed according the same mechanism involved in Merkel cell carcinoma pathogenesis. We proposed LCH developed from an inflammatory process that was sustained due to gene mutations. We hypothesized that MCPyV infection triggered an IL-1 activation loop that lies beneath the pathogenesis of LCH and propose a new triple-factor model.

Loeys-Dietz syndrome with aortic wall necrosis secondary to external wrapping.

External aortic wrapping may overcompress the aortic wall. An 18-year-old man underwent valve-sparing aortic root replacement for annuloaortic ectasia caused by Loeys-Dietz syndrome. External Dacron graft wrapping was performed to protect the ascending aorta. A year later, he underwent mitral valve repair. Intraoperatively, after unwrapping the external graft, the wrapped ascending aortic wall appeared necrotic. Histopathology showed damaged smooth muscle cells in the adventitia and outer media with unaffected inner layers and an intact intimal surface. Ischaemic necrosis of the aortic wall was associated with arterial insufficiency secondary to overcompression of the aortic wall that was already weakened by Loeys-Dietz syndrome. We describe a patient with Loeys-Dietz syndrome in whom pathognomonic necrosis in the wrapped aortic wall was observed histopathologically.

Pathological investigation of graft-related oesophageal fistula.

Oesophageal fistulae after thoracic endovascular aneurysm repair (TEVAR) for thoracic aortic aneurysm (TAA) have been reported, although the causes are unknown. One hypothesis is that the structural configuration of the aortic aneurysm, as it protrudes towards the oesophagus, may affect oesophageal fistula formation. The pathological findings of an oesophageal fistula following TEVAR are reviewed here. This report presents the case of a 68-year-old man with a stent graft-related oesophageal fistula after TEVAR for TAA. The oesophageal fistula suddenly appeared on the 11th day after TEVAR, and oesophagectomy was performed, without stent graft extirpation. The pathological findings showed neutrophil infiltration from the adventitia to the mucosa and congestion in the capillaries of the oesophageal wall around the site of penetration and no bacterial infection. There have been reports with logical hypotheses about the causes of stent graft-related oesophageal fistulae. Our pathological findings support the theory that pressure necrosis or ischaemic insult by physical compression of a rigid thrombosed aneurysm may result in fistula formation. For descending aortic aneurysms that protrude toward the oesophagus, caution must be exercised to prevent oesophageal fistula formation after TEVAR.