Follicular adenoma with a papillary architecture originating from an ectopic thyroid gland: a case report.

BACKGROUND: Follicular adenomas with papillary architecture are rare tumors of thyroid origin and are composed of completely encapsulated follicular cells with a papillary architecture lacking the nuclear characteristics of papillary carcinoma. Herein, we present a case of follicular adenoma with papillary architecture originating from an ectopic thyroid gland, diagnosed from a mass in the submandibular region. CASE PRESENTATION: A 70-year-old woman was referred to our hospital with the chief complaint of a painless left submandibular mass that had been present for one year. The patient underwent left submandibular dissection for therapy and diagnosis. Microscopically, papillary lesions with fibrovascular cores were observed in the interior, and the epithelial cells were cylindrical in shape with eosinophilic cytoplasm, round or oval nuclei, with no pathological features, leading to a diagnosis of papillary carcinoma or follicular carcinoma. The mass was diagnosed as a follicular thyroid adenoma with papillary architecture. This is the first report of a follicular adenoma with a papillary architecture originating from an ectopic thyroid gland. CONCLUSION: This experience suggests that follicular adenoma should be included in the differential diagnosis of ectopic thyroid tumors.

Clinical significance of antinuclear antibody as prognostic marker for first-line pembrolizumab in advanced non-small cell lung cancer.

BACKGROUND: The relationship between antinuclear antibody (ANA) and the efficacy of programmed death-1 (PD-1) blockade remains controversial. Here, we investigated the prognostic significance of ANA titer in patients with non-small cell lung cancer (NSCLC) receiving pembrolizumab monotherapy as the first-line treatment, compared with that of platinum-based chemotherapy with PD-1 blockade. METHODS: Our clinical data based on the ANA titer (1:80) were retrospectively reviewed for patients with advanced NSCLC, who were treated with first-line pembrolizumab monotherapy and platinum-based chemotherapy with PD-1 blockade. Immunohistochemical staining for tumor-infiltrating lymphocytes such as CD4, CD8 and Foxp3 was performed. RESULTS: Among 106 patients treated with pembrolizumab, 19 (17.9%) tested high for ANA. Progression-free survival (PFS) and overall survival (OS) were significantly better in patients with high ANA than in those with low ANA, and high ANA was identified as an independent prognostic predictor, particularly in the subgroup with programmed death ligand-1 (PD-L1) ≥ 50%. However, no statistically significant difference in PFS and OS based on the ANA titer was observed in 59 patients treated with combinational chemotherapy and immunotherapy. High numbers of intratumoral Foxp3 and stromal CD8 were significantly associated with low ANA. CONCLUSIONS: Assessment of preexisting ANA titers was useful to prognose PD-1 blockade as a first-line setting, particularly for the PD-L1 ≥ 50% subgroup, but not in the case of combined immunotherapy and chemotherapy.

IgG4-related disease with subcutaneous involvement and the associated diagnostic challenges with MRI.

IgG4-related disease is a rare fibroinflammatory disorder characterized by the infiltration of IgG4-rich plasma cells. Herein, we report a case of IgG4-related disease of the subcutaneous tissue with atypical MRI findings and difficulties in the histopathological examination using needle biopsy. Based on the clinical presentation and MRI findings, the patient was diagnosed with a benign myxoid or cystic tumor. Additionally, histopathological findings from a needle biopsy suggested a myxoma. Therefore, the correct diagnosis of IgG4-related disease was not made preoperatively. The resected specimens confirmed IgG4-related disease with an IgG4/IgG ratio > 80%. Previous reports have shown that the MRI findings of IgG4-related disease mimic both malignancy and inflammation; surprisingly, the features of subcutaneous IgG-related disease, including tail sign, unclear border, and heterogeneous enhancement, were similar to those found in sarcoma. Therefore, histopathological findings are needed for a correct diagnosis. Furthermore, careful examination is essential because the neoplasm and inflammation may overlap with IgG4-related disease, and needle biopsy is not fully reflective of the tumor. As is highlighted in the present case, IgG4-related disease is often misdiagnosed; therefore, clinicians should adequately recognize that even if the histopathological findings in biopsy were consistent with those observed in the MRI, misdiagnosis may occur.

Synovial chondromatosis: Rare involvement of metacarpophalangeal joint and diagnostic challenges in MR imaging.

Synovial chondromatosis (SC) is a rare benign tumor of the cartilaginous tissue that frequently affects large joints intra-articularly. Characteristic imaging findings were reported for the diagnosis of SC. Herein, we report a case of SC of the metacarpophalangeal joint with atypical MRI findings. Considering the clinical presentation, erosion, absence of calcification on X-ray and CT, and low intensity on short tau inversion recovery (STIR), tenosynovial giant cell tumor was the initially diagnosis. However, histopathological findings revealed SC with fibrosis, which was confirmed using Elastica Van Gieson (EVG) staining. In general, low intensity on STIR in SC indicate calcification; however, it can also represent fibrosis in SC. In this case, the diagnosis of SC using MRI was limited highlighting the importance of histopathological findings for an accurate diagnosis of SC.

Effectiveness of clip-and-thread traction-assisted duodenal endoscopic submucosal dissection: a propensity score-matched study (with video).

BACKGROUND AND AIMS: The indications for endoscopic submucosal dissection (ESD) in superficial nonampullary duodenal epithelial tumors (SNADETs) remain controversial because the procedure is technically challenging. Moreover, the effectiveness of clip-and-thread traction-assisted ESD (TA-ESD) for SNADETs has not been assessed. The aim of the current study was to compare the effectiveness of duodenal TA-ESD and conventional ESD for SNADETs. METHODS: SNADETs treated with conventional ESD or TA-ESD between April 2017 and March 2021 at Saitama Medical University International Medical Center were evaluated retrospectively. RESULTS: There were 49 cases of conventional ESD and 32 cases of TA-ESD for SNADETs. Using a propensity score-matched design, we selected 26 pairs of cases with conventional ESD and TA-ESD. In the unmatched cohort, patients treated with TA-ESD were characterized by a higher R0 (no tumor identified at the lateral or vertical margins) resection rate (P = .004), more frequent poor submucosal lifting because of fibrosis (P = .014), and shorter follow-up period (P = .0004) than patients treated with conventional ESD. In the propensity score-matched pairs, patients treated with TA-ESD were characterized by a higher rate of R0 resection (P = .021) and a shorter follow-up period (P = .0061). The findings regarding R0 resection rates were confirmed by multivariate logistic regression models, which found a higher odds ratio (OR) for R0 resection in patients who underwent TA-ESD than in patients who underwent conventional ESD both in the unmatched cohort (OR, 17.0; 95% confidence interval, 1.6-178.8; P = .018) and in the propensity score-matched pairs (OR, 26.7; 95% confidence interval, 1.5-460.2; P = .024). CONCLUSIONS: Our findings suggest TA-ESD may increase the rate of R0 resection in patients with SNADETs in comparison with conventional ESD.

A retrospective cohort study of factors influencing long procedure times in colorectal endoscopic submucosal dissection.

OBJECTIVE: To evaluate the outcomes and factors influencing colorectal endoscopic submucosal dissection (ESD) with a long procedure time. MATERIALS AND METHODS: In this single-center, retrospective study, we included 1,100 patients with 1,199 lesions who underwent colorectal ESD between April 2016 and December 2020. ESD was performed using an advanced system knife for lesions >20 mm. An S-O clip was used as the traction device. The long-time group (LP; procedure time >120 min) and normal-time group (NP; procedure time <120 min) were compared. RESULTS: The procedure times were 166.86 and 44.72 min in the LP and NP groups, respectively. The completion rate was higher in the NP group (96.5% vs. 83.5%, p = .001); the completed lesions were resected en bloc. Multivariate analysis revealed 18.8% and 7.8% of submucosal fibrosis in the LP and NP groups, respectively (odds ratio [OR] = 2.410, p = .026). Compared to the NP group, the LP group presented larger maximum lesion sizes and higher rates of R1 resection, and traction device use. Time to introduction of traction device use was longer in the LP than in the NP group (126.05 vs. 21.72 min; p < .001). Fibrosis tends to occur cecal lesions (OR 2.436, p = .011) and laterally spreading tumor-non-granular-pseudo-depressed (LST-NG-PD) (OR 2.6181, p = .001). CONCLUSIONS: Lesion size and fibrosis were factors associated with a long procedure time in colonic ESD. For fibrotic lesions (LST-NG-PD and cecal lesions), it is necessary to consider early use of traction devices and advisable to plan a strategy for the use of traction devices.

Methotrexate-associated lymphoproliferative disorders of T-cell phenotype: clinicopathological analysis of 28 cases.

Methotrexate-associated lymphoproliferative disorders are categorized as "other immunodeficiency-associated lymphoproliferative disorders in the WHO classification. Methotrexate-associated lymphoproliferative disorder is mainly a B-cell lymphoproliferative disorders or Hodgkin lymphoma type, whereas T-cell lymphoproliferative disorders are relatively rare (4-8%). Only a small number of methotrexate-associated T-cell lymphoproliferative disorders have been detailed thus far. Because of the rarity, methotrexate-associated T-cell lymphoproliferative disorder has not been well studied and its clinicopathological characteristics are unknown. A total of 28 cases of methotrexate-associated T-cell lymphoproliferative disorders were retrospectively analyzed. Histologically and immunohistochemically, they were divided into three main types: angioimmunoblastic T-cell lymphoma (n = 19), peripheral T-cell lymphoma, NOS (n = 6), and CD8+ cytotoxic T-cell lymphoma (n = 3). Among the 28 cases, only one CD8+ cytotoxic T-cell lymphoma case was Epstein-Barr virus-positive. The other 27 cases were negative for Epstein-Barr virus on tumor cells, but scattered Epstein-Barr virus-infected B-cells were detected in 24 cases (89%), implying the reactivation of Epstein-Barr virus caused by immunodeficient status of the patients. After the diagnosis of methotrexate-associated T-cell lymphoproliferative disorder, methotrexate was immediately withdrawn in 26 cases. Twenty (77%) cases presented with spontaneous regression. Compared to methotrexate-associated B-cell lymphoproliferative disorder, patients with methotrexate-associated T-cell lymphoproliferative disorder had a significantly higher proportion of males (p = 0.035) and presence of B-symptoms (p = 0.036), and lower proportion of Epstein-Barr virus+ tumor cells (p < 0.001). Although the difference was not significant, the methotrexate-associated T-cell lymphoproliferative disorder also had more frequent spontaneous regression (p = 0.061). In conclusion, methotrexate-associated T-cell lymphoproliferative disorder was divided into three main types: angioimmunoblastic T-cell lymphoma, peripheral T-cell lymphoma, NOS, and CD8+ cytotoxic T-cell lymphoma. Angioimmunoblastic T-cell lymphoma was the most common type. Methotrexate-associated T-cell lymphoproliferative disorder was characterized by a high rate of spontaneous regression after methotrexate cessation. Epstein-Barr virus positivity was relatively rare in methotrexate-associated T-cell lymphoproliferative disorder, significantly less frequent than methotrexate-associated B-cell lymphoproliferative disorder, suggesting different pathogenesis.

[Left Atrial Myxoma with Ossification;Report of a Case].

A 69-year-old female with left atrial tumor was refered to our hospital for surgical treatment. The tumor was attached to the interatrial septum and resected completely. Histopathological analysis confirmed a myxoma with ossification(mature bone). These findings may support the hypothesis that the undifferentiated mesenchymal cells are the origin of cardiac myxoma.

Clinicopathological and molecular alterations in early gastric cancers with the microsatellite instability-high phenotype.

The relevance of the clinicopathological and molecular features of early gastric cancers (EGCs) having the microsatellite instability (MSI)-high phenotype has not been clearly defined in sporadic gastric carcinogenesis. Here, we examined the clinicopathological and molecular characteristics of EGC according to MSI status in 330 patients with EGC (intestinal-type adenocarcinoma). Tumors were classified as MSI-high (45 cases), MSI-low (9 cases), or microsatellite stable (MSS; 276 cases). The specimens were examined using a combination of polymerase chain reaction (PCR)-microsatellite assays and PCR-pyrosequencing to detect chromosomal allelic imbalances in multiple cancer-related chromosomal loci, MSI, gene mutations (KRAS and BRAF) and methylation status [high methylation epigenome (HME), intermediate methylation epigenome and low methylation epigenome]. In addition, the expression levels of various target proteins were examined using immunohistochemistry. Interestingly, EGC with the MSI phenotype showed distinct papillary features. The expression of gastric mucin was more frequent in EGC with the MSI phenotype, while p53 overexpression was common in EGCs, irrespective of MSI status. The frequency of HME was significantly higher in EGCs with the MSI phenotype than in EGCs with the MSS phenotype. Although there was a low frequency of allelic imbalance in EGCs with the MSI phenotype, some markers of allelic imbalance were more frequently detected in EGCs with the MSI-high phenotype than in EGCs with the MSS phenotype. KRAS and BRAF mutations were rare in EGCs. Thus, the MSI phenotype in EGC is a major precursor lesion in gastric cancer and is characterized by distinct clinicopathological and molecular features.

Subcutaneous porocarcinoma clinically presenting as a soft tissue tumor.

Porocarcinoma is a rare malignancy with glandular adnexal differentiation. A 38-year-old Japanese man noticed a subcutaneous mass in right inguinal region about 20 years prior to being examined. Radiological examinations demonstrated the mass, 11 × 10 cm in size, was in the subcutaneous fat tissue. Recently, the mass grew rapidly, and it was biopsied by an orthopedist based on clinical diagnosis of primary soft tissue tumor. Histopathological examination of the resected specimens also revealed that the tumor lacked involvement to the skin. Microscopically, the tumor was mainly composed of poroid cells with partially obvious squamous differentiation, accompanied by focal ductal structures immunoreactive for CEA and EMA. The tumor contained a low-grade area consisting of poroid cells and high-grade area with squamous differentiation. This histopathological heterogeneity suggested malignant transformation from poroma. The patient had the tumor in almost same size over the period of 20 years, which is the longest in the previous reports. This unique case of subcutaneous porocarcinoma is reported.

Molecular analysis of isolated tumor glands from endometrial endometrioid adenocarcinomas.

We studied the extensive molecular alterations of endometrial endometrioid adenocarcinoma (EEA) using a crypt isolation method. We analyzed copy number variation (CNV) using a single nucleotide polymorphism (SNP) array, genetic mutations (KRAS, BRAF, p53, PIK3CA), DNA methylation and microsatellite instability (MSI) status. In addition, loss of PTEN protein expression was examined. Increased chromosome copy numbers of 1q21.2-44 (22%) and 10q11.21-23.31 (28%) were seen relatively frequently in EEA, and copy-neutral loss of heterozygosity (LOH) was also observed in 10q22.1-26.3 (22%). The CNV patterns of EEA were classified into four groups through hierarchical cluster analysis. Cluster 1 had many CNVs of 10q, and cluster 2 was characterized by MSI status. In cluster 3, increased CNVs of 1q were often seen. In cluster 4, p53 mutations were detected. KRAS and PIK3CA mutations and reduced PTEN protein expression were common to all groups. On the other hand, CpG island methylator phenotype (CIMP) was rare in all groups. The data indicated an association with chromosomal gain of 1q and 10q or 10q copy-neutral LOH in some cases. We suggest that EEA consists of four groups that are characterized with molecular alterations.

Proposal for novel histological findings of colorectal liver metastases with preoperative chemotherapy.

This study aimed to clarify the histological characteristics related to preoperative chemotherapy for colorectal liver metastases (CRLM). Sixty-three patients with CRLM were divided into two groups: CRLM with chemotherapy (41 cases, group A) and CRLM without chemotherapy (22 cases; surgical treatment alone, group S) to identify the histological differences associated with chemotherapy. In addition, we investigated the effects of combination chemotherapy on the histology of metastatic lesions. Infarct-like necrosis (ILN), three-zonal changes, and cholesterol clefts were more frequent in group A than in group S (P < 0.05). ILN and three-zonal changes were more common in the 5-FU with leucovorin and oxaliplatin (FOLFOX), or 5-FU with leucovorin and irinotecan (FOLFIRI) with or without additional bevacizumab groups than in group S (P < 0.05). Cholesterol clefts in the FOLFOX or FOLFIRI with bevacizumab group and foamy macrophages in the FOLFOX or FOLFIRI group were more common than in group S (P < 0.05). Cases with more than three of the four histological findings--i.e. ILN, three-zonal changes, cholesterol clefts, and foamy macrophages--were more frequent in the FOLFOX or FOLFIRI with or without additional bevacizumab groups than in group S (P < 0.05). We showed histological findings for every representative chemotherapy regimen for CRLM to clarify the effects of preoperative chemotherapy.