Histological spectrum of angiofibroma of soft tissue: histological and genetic analysis of 13 cases.

AIMS: Angiofibroma of soft tissue (AFST) is a rare soft tissue neoplasm characterized by a fibroblastic cytomorphology and a prominent vascular structure. AFSTs possess a novel fusion gene, i.e. NCOA2-AHRR/AHRR-NCOA2 or GTF2I-NCOA2, providing a useful approach to diagnosing AFST. Morphologically, AFSTs span a wide spectrum, making diagnosis a challenge. The aim of this study was to review AFST cases and to report previously unknown histological features, which we confirmed by genetic analysis. METHODS AND RESULTS: We reviewed 276 cases diagnosed as solitary fibrous tumours/haemangiopericytomas (232 cases), unclassified tumours of fibroblastic differentiation (36 cases), and recently diagnosed AFSTs (eight cases), and retrieved 13 cases compatible with AFST. Immunohistochemical staining was performed for these cases, all 13 of which were analysed by reverse transcription polymerase chain reaction and fluorescence in-situ hybridization. The histological findings were as follows: amianthoid fibres, extravasation of red blood cells, haemosiderin deposition, aggregates of foamy histiocytes, cystic change, necrosis, and haemorrhage. Immunohistochemically, the tumour cells were positive for epithelial membrane antigen (four of 13 cases), desmin (six of 13 cases), CD163 (13 of 13 cases), CD68 (seven of 13 cases), oestrogen receptor (13 of 13 cases), progesterone receptor (three of 13 cases), and STAT6 (one of 13 cases, weak nuclear staining), but they were negative for CD34, α-smooth muscle actin, muscle-specific actin, S100, pan-cytokeratin, MDM2, and CDK4. The AHRR-NCOA2 fusion gene was detected in eight cases, and NCOA2 gene rearrangement in nine cases. CONCLUSION: We revealed the previously unreported histological variation and immunohistochemical findings of AFST, and confirmed them by using genetic methods. The results suggested that AFST should be considered in the diagnosis of fibrous or fibrohistiocytic tumours with the above histological features.

Synchronous double primary lung cancers with different response to pemetrexed.

We describe the case of a 74-year-old male patient with synchronous double primary lung cancers: adenocarcinoma in the right lower lobe and squamous cell carcinoma in the left upper lobe (LUL). These tumors were difficult to differentiate radiographically from a single metastatic primary cancer, but their eventual diagnoses were triggered by their responses to chemotherapy, which included pemetrexed. After two courses of chemotherapy with pemetrexed and carboplatin, the right lower lobe mass had partially resolved; however, the LUL mass had increased. When S-1 was used as fourth-line chemotherapy, the size of the LUL mass decreased. Pemetrexed is a potentially useful drug for treating nonsquamous cell carcinoma, but may not be appropriate in cases with a coexisting squamous cell carcinoma. Our experience with this interesting case leads us to propose that S-1 monotherapy may provide a treatment option in pemetrexed-refractory cases.

Pedunculated inverted hyperplastic polyp of the sigmoid colon treated with endoscopic polypectomy.

A case of inverted hyperplastic polyp of the sigmoid colon is reported. The patient was a 67-year-old woman who visited our hospital for further evaluation of constipation. Colonoscopy revealed a pedunculated polyp with linear central depression, about 12 mm in diameter, in the sigmoid colon. Excluding the polyp, there was no lesion in the colorectum. Endoscopic polypectomy was performed. Histological examination of the specimen revealed a stalked polyp that had scattered goblet cells and elongated tubules with serrated profiles in the superficial portion. The nodules of deep tubules impinged on the muscularis mucosae. Proliferation of fibromuscular tissue was not seen in the polyp. There was no evidence of malignancy. This polyp was diagnosed as an inverted hyperplastic polyp. Pedunculated-type inverted hyperplastic polyp of the colon is rare.

[A case of liposarcoma of the ascending colon mesenterium].

We encountered a rare case of liposarcoma of the ascending colon mesenterium. A 53-year-old man visited our hospital because of a mass, 12x8cm in diameter, in the right upper abdomen. On computed tomography (CT), the tumor showed irregular density with a smooth surface and was enhanced irregularly. A part of the tumor protruded into the colon in the upper portion of the ascending colon. The tumor was surgically resected by right hemicolectomy. Histological diagnosis of the tumor was well-differentiated liposarcoma, sclerosing variant. Radiological findings seemed to reflect the pathological findings well.

A ruptured large extraluminal ileal gastrointestinal stromal tumor causing hemoperitoneum.

We describe an 87-year-old woman with a large ileal gastrointestinal stromal tumor (GIST) causing hemoperitoneum. A CT scan demonstrated a large heterogeneous mass measuring about 13 cm multiply 11 cm in the pelvis and hemoperitoneum, with a non-uniform enhancement pattern. The mass was diagnosed as a GIST originating from the gastrointestinal tract. She underwent an urgent laparotomy and an ileal GIST with a rupture was found 130 cm from the anal to the Treitz's ligament. Hemoperitoneum caused by ileal GIST rupture is a rare condition. Bleeding in the large tumor leading to rupture of the capsule might cause hemoperitoneum in the present case.

Magnifying endoscopy for intestinal follicular lymphoma is helpful for prompt diagnosis.

The representative endoscopic features of primary intestinal follicular lymphoma are well known as small whitish polypoid nodules, but a magnified view has only been described in a few case reports. Herein, we report a case with intestinal follicular lymphoma in which magnifying endoscopy with narrow band imaging was helpful for prompt diagnosis. A 57-year-old Japanese woman underwent surveillance esophagogastroduodenoscopy. The endoscopic examination revealed confluent whitish granules in the duodenum, distinct from the nodules or polyps that are typical findings of intestinal follicular lymphoma. Magnifying endoscopy visualized whitish enlarged villi, and narrow band imaging emphasized an elongated and coiled vascular pattern. Based on these features, intestinal follicular lymphoma was highly suspected, and subsequent histological study confirmed the diagnosis. This case demonstrates that magnifying endoscopy with narrow band imaging was useful for the detection and prompt diagnosis of intestinal follicular lymphoma. The pathological features of intestinal follicular lymphoma are also discussed.

Cavitary pulmonary involvement of diffuse large B-cell lymphoma transformed from extra nodal marginal zone B-cell lymphoma MALT type.

We describe a case of pulmonary diffuse large B-cell lymphoma (DLBCL), which was thought to arise from extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). A 68-year-old woman presented with a 2-month history of cough and bloody sputum. The chest X-ray and computed tomography revealed a mass with cavitation in the right lower lobe. Transbronchial biopsy specimens revealed a granulomatous infiltration without malignant cells. However, diagnosis of MALT lymphoma was established from gastric biopsy specimen. Subsequently, a right lower lobectomy was performed because of hemoptysis. Examination of the resected specimen revealed a diffuse large B-cell lymphoma, which was considered to have transformed from MALT lymphoma, because both lung and stomach lesions had the chromosomal translocation t(11;18)(q21;q21) in common. In addition, there were no nodules, masses, alveolar or interstitial infiltrates in the lung fields, which are usually observed in the case of marginal zone B-cell lymphoma of bronchial mucosa-associated lymphoid tissue. These findings indicate that involvement of DLBCL have to be considered in patients with MALT lymphoma and cavitary lesion of the lung.

Centrally located squamous cell carcinoma of the lung mimicking endobronchial tuberculosis.

Here we report a case of centrally located squamous cell carcinoma of the lung mimicking endobronchial tuberculosis. On the basis of the white light bronchoscopic (WLB) findings, bronchial tuberculosis was initially suspected. But transbronchial biopsy of the lesion revealed squamous cell carcinoma. Autofluorescence imaging bronchovideoscopy (AFI) showed the lesion area as magenta. After four cycles of chemotherapy, the magenta area was markedly shrunk on AFI. Performance of AFI might be useful for differentiating centrally located lung cancer from endobronchial tuberculosis.

Inflammatory myoglandular polyp causing hematochezia.

A case of inflammatory myoglandular polyp (IMGP) causing hematochezia is reported. The patient was a 33-year-old man who visited our hospital for further evaluation of hematochezia. Colonoscopy revealed a red, hard, spherical peduncular polyp with erosion and mucous exudation, about 20 mm in diameter, in the descending colon. Excluding the polyp, there was no lesion in the colorectum. Endoscopic polypectomy was performed. Histological examination of the specimen revealed inflammatory granulation tissue in the lamina propria, proliferation of smooth muscle, and hyperplastic glands with variable cystic changes. This polyp was diagnosed as an IMGP. The symptom of hematochezia was resolved after endoscopic resection. Our case shows that treatment is necessary for IMGP if intestinal bleeding occurs and endoscopists should be aware of the endoscopic characteristics of IMGP.