Distinctive clinicopathological features of adenocarcinoma in situ and minimally invasive adenocarcinoma of the lung: A retrospective study.

OBJECTIVES: The aim of this study was to investigate distinguishing clinicopathological features, in addition to histological invasiveness, in adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) of the lung. MATERIALS AND METHODS: Patients with lung adenocarcinoma who underwent surgery at our hospital between 2007 and 2014 were reviewed, focusing on computed tomography (CT) images, operative procedures and clinical outcomes, histopathology, Ki-67 immunostaining, and EGFR-mutation status. EGFR mutations were examined using a peptide nucleic acid-locked nucleic acid PCR clamp method. Group comparisons were investigated by Mann-Whitney U or Fisher's exact tests. RESULTS: Of 629 patients with lung adenocarcinoma who underwent surgery, 91 (14%) of 103 AIS (n = 34) or MIA (n = 69) tumors were reviewed. The ratio of male to female patients with MIA compared to AIS was significantly higher (p < 0.02). Of 103 tumors, 99 (96%) were non-mucinous. By CT, 74% of AIS appeared as pure ground-glass nodules and 75% of MIAs as part-solid ground-glass nodules. Pathological tumor diameters and Ki-67 labeling index (LI) values were significantly greater for MIAs compared to AIS (p < 0.001 for both). A Ki-67 LI of ≥2.8% indicated the presence of an MIA rather than an AIS. EGFR mutations were more frequently detected in MIAs (33/69, 48%) than AIS (9/34, 26%; p = 0.055). The ratio of exon 19 deletions to exon 21 missense mutations in MIAs tended to be higher than those in AIS (p = 0.06). Patients did not experience a local recurrence or metastasis after AIS and MIAs were removed by wedge resection, segmentectomy or lobectomy. Five-year recurrence-free survival rates were 100%. CONCLUSION: Despite similar surgical outcomes for AIS and MIAs, we found differences in terms of gender, tumor diameters, CT findings, Ki-67 LI and a subset of EGFR mutations, highlighting the validity of classifying the two subtypes.

Characterization of Three Fungal Isomaltases Belonging to Glycoside Hydrolase Family 13 That Do not Show Transglycosylation Activity.

α-1,6-Glucosidase (isomaltase) belongs to glycoside hydrolase (GH) families 13 and 31. Genes encoding 3 isomaltases belonging to GH family 13 were cloned from filamentous fungi, Aspergillus oryzae (agl1), A. niger (agdC),and Fusarium oxysporum (foagl1), and expressed in Escherichia coli. The enzymes hydrolyzed isomaltose and α-glucosides preferentially at a neutral pH, but did not recognize maltose, trehalose, and dextran. The activity of AgdC and Agl1 was inhibited in the presence of 1 % glucose, while Foagl1 was more tolerant to glucose than the other two enzymes were. The three fungal isomaltases did not show transglycosylation when isomaltose was used as the substrate and a similar result was observed for AgdC and Agl1 when p-nitrophenyl-α-glucoside was used as the substrate.

[Tumors of the diaphragm, diagnosis and surgical treatment].

Primary tumors of the diaphragm are very rare, and we often have difficulties in preoperative diagnosis and accurate evaluation of invasion. We experienced 3 surgical cases of tumor of diaphragm:primary mucinous adenocarcinoma, metastatic gastrointestinal stromal tumor, and mesothelioma. Besides computed tomography (CT) and conventional magnetic resonance imaging(MRI), respiratory dynamic cine magnetic resonance imaging (cine MRI) was performed. Cine MRI was acquired using steady state free precession (SSFP) sequence, and about 80 consecutive images of the same slice were taken while a patient breathed deeply. In all cases, cine MRI showed lack of tumor movement along the diaphragm during respiration. During surgery, we found that tumor was originated from diaphragm and there was no adhesion to other organs. Securing a sufficient margin, we resected tumor including the diaphragm. Since the defect of diaphragm was from 4 to 5cm in short diameter, we could close the diaphragm by direct suture. Cine MRI could provide useful information concerning discrimination between diaphragmatic and para-diaphragmatic tumor.

Primary mucinous adenocarcinoma of the posterior mediastinum.

We report a rare case of primary mucinous adenocarcinoma of the posterior mediastinum. A 36-year-old man was referred to our hospital with right flank pain. Computed tomography showed a cystic mass in the posterior mediastinum, and the tumor displaced the diaphragm downward and the inferior vena cava forward. The patient underwent extirpation of the tumor. The cut surface of the resected tumor showed a unilocular cyst filled with abundant gray gelatinous fluid. Microscopically, the tumor had a fibrous capsule lined with cuboidal and columnar malignant epithelial cells with intracellular mucin accumulation and was diagnosed as a mucinous adenocarcinoma.