Evaluation of Clinical Significance of Lymphovascular Space Invasion in Stage IA Endometrial Cancer.

INTRODUCTION: The prognostic significance of lymphovascular space invasion (LVSI) in stage IA endometrial cancer remains unclear. The aim of this study was to evaluate the clinical significance of LVSI in stage IA endometrial cancer. METHODS: Clinical data of patients with stage IA endometrial cancer who underwent initial surgery at our institution between January 2008 and December 2018 were reviewed retrospectively. Information of patients, surgery, and characteristics of cancer were obtained from medical records and pathological reports. RESULTS: Two hundred ninety-seven patients were enrolled in this study. With a median follow-up of 60 months, 15 patients experienced recurrence (5.1%) and 4 patients died of endometrial cancer (1.3%). The recurrence and mortality rates did not differ significantly between the LVSI-positive and -negative groups (p = 0.07 and p = 0.41, respectively). Recurrence-free survival and endometrial cancer-specific survival also did not differ significantly between these groups (p = 0.11 and p = 0.49, respectively). The 5-year endometrial cancer-specific survival rates for tumors with and without LVSI were 97.0% and 98.9%, respectively. Among patients with low-grade tumors, recurrence-free survival and endometrial cancer-specific survival did not differ significantly between patients with tumors with and without LVSI (p = 0.92 and p = 0.72, respectively). The 5-year endometrial cancer-specific survival rates for low-grade tumors with and without LVSI were 100% and 99.3%, respectively. CONCLUSION: LVSI was not a prognostic factor of not only stage IA endometrial cancer but also stage IA low-grade cancer.

Long-term follow up after sentinel node biopsy alone for early-stage cervical cancer.

OBJECTIVE: Sentinel node biopsy alone (SNB) reduces the postoperative complications of pelvic lymphadenectomy, such as lymphedema and lymphangitis; however, the long-term prognosis after SNB is unclear. The objective of this study was to evaluate the long-term outcome and complications of patients with early-stage cervical cancer who underwent SNB for hysterectomy or trachelectomy. METHODS: We performed SNB for cervical cancer using a radioisotope method in 181 patients between 2009 and 2017. If the intraoperative sentinel lymph node evaluation was negative for metastasis, no further lymph nodes were removed. RESULTS: The median age of the patients was 34 years (range, 21-73 years). The International Federation of Gynecology and Obstetrics 2008 stage was IA1 in 6 patients, IA2 in 18, IB1 in 154, and IIA1 in 3. Of the 181 patients (44 with hysterectomy, 137 with trachelectomy), 8 did not undergo pelvic lymphadenectomy because of a false-negative intraoperative diagnosis, 20 received adjuvant therapy after surgery, and 4 (2.2%) experienced recurrence over a median follow-up period of 83.5 months (range, 25-145 months). In the four recurrent cases, recurrence occurred in the pelvis, lung, and bone in one patient each, while the remaining patient developed pelvic and para-aortic lymph node metastases. Of these four patients, one died, and the remaining three are alive without disease after multidisciplinary therapy. The 5-year progression-free and overall survival rates were 98.8% and 99.4%, respectively. Postoperative complications, such as lymphedema, were very low rate. CONCLUSIONS: SNB for early-stage cervical cancer might be safe and effective, with no increase in the recurrence and postoperative complications rate.

A critical review of "uterine leiomyoma" with subsequent recurrence or metastasis: A multicenter study of 62 cases.

AIM: Histopathologic diagnosis of a subset of uterine smooth muscle tumors is challenging. We report a critical review regarding the clinicopathological point of view of 62 cases of subsequently recurred or metastasized leiomyoma. METHODS: Medical records and glass slides of 62 cases of uterine smooth muscle tumor diagnosed as leiomyoma, which subsequently recurred or metastasized, were critically reviewed by pathologists specializing in gynecologic pathology and oncology. RESULTS: In 47 (75.8%) of 62 cases, the diagnosis of leiomyoma was confirmed, including 11 intravascular leiomyomatosis (IVL) and benign metastasizing leiomyoma (BML). In 29 cases (46.8%) laparoscopic surgery was performed, of which morcellator without a bag was employed in 23 cases. Fifteen cases (24.2%) appeared to be underestimated and were re-classified as smooth muscle tumor of uncertain malignant potential (STUMP), leiomyosarcoma, or other malignant mesenchymal tumors. Recurrences in seven cases (11.3%) were interpreted to be a malignant transformation, and one STUMP recurred as STUMP. CONCLUSION: The recurrence or metastasis in cases of "leiomyoma" is attributed to iatrogenic or under-evaluation of primary tumors, although a subset of cases is a rare example of biological progression.

Endometrial endometrioid carcinoma, grade 1, is more aggressive in the elderly than in the young.

AIMS: The aim of this study was to characterise grade 1 (G1) endometrioid carcinoma in the elderly, by using clinicopathological features and immunohistochemical features of surrogate markers of molecular subtypes. METHODS AND RESULTS: We retrospectively analysed tumour samples from 268 patients with G1 endometrioid carcinoma (<40 years, n = 24; 40-59 years, n = 169; ≥60 years, n = 75) for whom long-term clinical follow-up data were available. G1 endometrioid carcinoma in the elderly (≥60 years) was characterised by frequent deep myometrial invasion, less frequent endometrioid intraepithelial neoplasia (EIN), lack of benign hyperplasia (BH), less frequent squamous differentiation, and occasional aberrant p53 expression. In contrast, this condition in the young (<40 years) was characterised by frequent EIN, BH, and squamous differentiation. Univariate analysis revealed that elderly status (≥60 years), International Federation of Obstetrics and Gynecology (FIGO) 2009 stage and aberrant p53 expression were significantly associated with shorter progression-free survival, and multivariate analysis revealed that elderly status and FIGO 2009 stage were independently associated with a poor prognosis. CONCLUSIONS: G1 endometrioid carcinoma in the elderly is more aggressive than that in the young, and elderly status is an independent predictor of shorter progression-free survival in this condition. We propose that type 1 tumours can be subdivided into type 1a (young age at onset and indolent) and type 1b (old age at onset and relatively aggressive).

Concomitant Intraductal Papillary Mucinous Neoplasm in Pancreatic Ductal Adenocarcinoma Is an Independent Predictive Factor for the Occurrence of New Cancer in the Remnant Pancreas.

OBJECTIVE: To determine the factors predicting the subsequent development of pancreatic ductal adenocarcinoma in remnant pancreas (PDAC-RP) after partial pancreatectomy for PDAC. SUMMARY BACKGROUND DATA: PDAC-RP after partial pancreatectomy for PDAC is currently not so rare because of improved prognosis of PDAC patients due to recent advances in surgical techniques and adjuvant therapy. However, the predictive factors related to PDAC-RP remain unknown. METHODS: We retrospectively reviewed the clinicopathological data of a consecutive series of 379 patients with PDAC treated by partial pancreatectomy between 1992 and 2015; 14 patients (3.69%) had PDAC-RP. Clinicopathological variables were compared between PDAC-RP and non-PDAC-RP. RESULTS: In univariate analysis, concomitant intraductal papillary mucinous neoplasm (IPMN) (P = 0.0005), cancer location (body/tail) (P = 0.0060), and lower T factor in UICC (P = 0.0039) were correlated with PDAC-RP development. Multivariate analysis revealed concomitant IPMN (P = 0.0135) to be an independent predictive factor for PDAC-RP. PDAC concomitant with IPMN had higher cumulative incidence of PDAC-RP (47.5%/10 yrs) than PDAC without IPMN (9.96%/10 yrs) (P = 0.0071). Moreover, the density of pancreatic intraepithelial neoplasia lesions in the background pancreas of cases of PDAC concomitant with IPMN (1.86/cm) was higher than that of cases of PDAC without IPMN (0.91/cm) (P = 0.0007). CONCLUSIONS: Concomitant IPMN in PDAC is an independent predictive factor for the development of new PDAC in remnant pancreas. Cancer susceptibility of remnant pancreas after resection for PDAC concomitant with IPMN is probably due to an increased density of pancreatic intraepithelial neoplasia lesions.

Clinicopathological features and phenotypic classification of de novo-type colorectal carcinomas differ from those of colorectal carcinomas derived from flat adenomas.

Since adenoma components disappear with tumor progression, it is not known whether colorectal carcinomas (CRCs) are derived from an adenoma-carcinoma sequence or are de novo. We compared 38 cases of ≤10-mm flat CRCs without an adenoma component (de novo type) with 39 cases of ≤10-mm flat CRCs with an adenoma component (carcinoma in adenoma (CIA) type). Compared to the CIA type, the de novo-type CRCs were more frequently located in the proximal colon; more frequently invaded submucosa, and more frequently had venous permeation. Regarding the phenotypic classification based on the immunohistochemical expressions of CD10, MUC2 and MUC5AC, the incidence of unclassified type (CD10-, MUC2- and MUC5AC-) was significantly more frequent in the de novo (32%) than CIA (5%) type. In one de novo-type case, mismatch repair (MMR) protein loss was judged, because MLH1 and PMS2 protein expressions were immunohistochemically negative. BRAF mutation (V600E) was seen in one de novo-type case and two CIA-type cases, but none of these cases had MMR protein loss. In conclusion, small-intestinal type (CD10+ and MUC5AC-) is the most common in flat CRC and unclassified type is mainly characteristic of de novo type. In this study, small flat CRCs with BRAF mutation do not have MMR protein loss.

Risk factors for failure of vitrectomy cell block technique in cytological diagnosis of vitreoretinal lymphoma.

PURPOSE: To determine the factors that may affect the accuracy of vitrectomy cell block technique in detecting atypical lymphoid cells in patients with vitreoretinal lymphoma (VRL). METHODS: We retrospectively reviewed 43 eyes in 39 patients who underwent vitrectomy for definitive histological diagnosis of VRL with vitrectomy cell block technique and/or smear preparation at Kyushu University Hospital from January 2001 to March 2016. The association of detection of atypical lymphoid cells using vitrectomy cell block technique with the following factors was assessed using logistic regression analysis: age at diagnosis, sex, presence or absence of concurrent cataract surgery with vitrectomy, clinical grading of vitreous haze, presence or absence of subretinal tumor infiltration, interval between initial symptoms and vitrectomy, and presence or absence of systemic corticosteroid therapy before vitrectomy. RESULTS: Atypical lymphoid cells were more significantly detected using vitrectomy cell block technique compared to that using smear preparation (p = 0.018). After adjusting for age and sex, concurrent cataract surgery (odds ratio [OR], 10.41; 95% confidence interval [CI], 1.42-76.41) and subretinal tumor infiltration (OR, 5.06; 95% CI, 1.06-24.32) were significantly associated with failure of histological analysis with vitrectomy cell blocks. In multivariable logistic regression analysis, similar results were obtained, although subretinal tumor infiltration was only marginally associated with the detective capability of the technique. CONCLUSION: Vitrectomy cell block technique significantly improved the definitive diagnosis of VRL. Concurrent cataract surgery with vitrectomy and subretinal tumor infiltration were risk factors for failure in vitrectomy cell blocks.

Amide Proton Transfer MR Imaging of Endometrioid Endometrial Adenocarcinoma: Association with Histologic Grade.

Purpose To evaluate the utility of amide proton transfer (APT) imaging in estimating histologic grades of endometrioid endometrial adenocarcinoma (EEA). Materials and Methods The institutional review board approved this prospective study. Between June 2012 and March 2016, 32 patients with EEA underwent magnetic resonance (MR) imaging. After their surgical procedures, their EEAs were confirmed pathologically and classified into histologic grades: grade 1 (n = 11), grade 2 (n = 11), and grade 3 (n = 10). The APT signal intensities (SIs) and the mean and minimum apparent diffusion coefficients (ADCs) of the three grades were calculated and compared. Spearman rank correlation coefficient was also calculated between the APT SIs and histologic grades, and between the ADCs and histologic grades. Results The Spearman correlation coefficient with histologic grade of the APT SIs, the mean ADC, and the minimum ADC were 0.55 (P = .001), 0.03 (P = .84), and -0.30 (P = .09), respectively. The average APT SIs and the mean and minimum ADCs were 2.2% ± 0.2 (standard deviation), 0.9 × 10-3 mm2/sec ± 0.2, and 0.6 × 10-3 mm2/sec ± 0.1 for grade 1; 3.2% ± 0.3, 0.8 × 10-3 mm2/sec ± 0.1, and 0.5 × 10-3 mm2/sec ± 0.1 for grade 2; and 3.7% ± 0.3, 0.9 × 10-3 mm2/sec ± 0.1, and 0.5 × 10-3 mm2/sec ± 0.1 for grade 3, respectively. The APT SIs of grade 3 EEA were significantly higher than those of grade 1 EEA (P = .01), but other pairwise comparisons did not reveal any significant differences (P = .06-.51). The mean and minimum ADCs showed no significant differences among the three histologic grades (P =.13-.51). Conclusion The APT SI was positively correlated with the histologic grades of EEA. © RSNA, 2017 Online supplemental material is available for this article.

'Microcystic pattern' should be recognised as part of the morphological spectrum of solid-pseudopapillary neoplasm of the pancreas.

AIM: Solid pseudopapillary neoplasm (SPN) is an uncommon pancreatic tumour characterised by solid and pseudopapillary growth patterns. We have observed SPNs can show a microcystic pattern (microcystic SPN), which has been poorly described and may be confused with microcystic neoplasms. We conducted the present study to clarify the clinicopathological and immunohistochemical features of microcystic SPNs. METHODS AND RESULTS: We examined a consecutive series of 44 SPNs and 10 serous cystadenomas (SCAs), and classified them into 13 microcystic SPNs (29.5%) and 31 conventional SPNs (70.5%). Clinicopathological analysis, immunohistochemical staining and mucin histochemistry were performed. Clear cell change, hyalinised stroma and haemorrhage were observed significantly more frequently in the microcystic SPNs compared to the conventional SPNs. Immunohistochemically, the microcystic SPNs showed significantly lower frequencies of CD10 (0%) and CD56 expression (62%) compared to the conventional SPNs (87%; P < 0.001, 90%; P < 0.0085, respectively). There were no significant differences in other clinicopathological and immunohistochemical features between the two groups (i.e. the nuclear expression of ß-catenin, E-cadherin, progesterone receptor (PgR), lack of forkhead box (Fox)L2 and occasional oestrogen receptor (ER), AE1/AE3 expression). Microcystic SCAs lack such a characteristic immunophenotype. The myxoid stroma of microcystic SPNs contained hyaluronan revealed by Alcian blue stain with hyaluronidase digestion. CONCLUSION: We thus conclude that the microcystic pattern should be recognised as a part of the morphological spectrum of SPNs. Our findings may contribute to the correct diagnosis of the pancreatic neoplasms with the microcystic pattern. In addition, we speculate that stromal change caused by an accumulation of hyaluronan may contribute to the microcystic pattern of SPN.

Insulin-like growth factor II messenger RNA-binding protein-3 is an independent prognostic factor in uterine leiomyosarcoma.

AIMS: The aim of this study was to identify the prognostic factors of uterine leiomyosarcoma (ULMS). METHODS AND RESULTS: We reviewed 60 cases of surgically resected ULMSs and investigated conventional clinicopathological factors, together with the expression of insulin-like growth factor II messenger RNA-binding protein-3 (IMP3), hormone receptors and cell cycle regulatory markers by immunohistochemistry. Mediator complex subunit 12 (MED12) mutation analysis was also performed. Univariate analyses revealed that advanced stage (P < 0.0001), older age (P = 0.0244) and IMP3 expression (P = 0.0011) were significant predictors of a poor outcome. Multivariate analysis revealed advanced stage (P < 0.0001) and IMP3 (P = 0.0373) as independent predictors of a poor prognosis. Expressions of cell cycle markers and hormone receptors, and MED12 mutations (12% in ULMSs) were not identified as prognostic markers in this study. CONCLUSIONS: IMP3 expression in ULMS could be a marker of a poor prognosis.

Prognostic outcome and complications of sentinel lymph node navigation surgery for early-stage cervical cancer.

BACKGROUND: To evaluate the prognostic outcome and surgical complications in patients with early-stage cervical cancer who underwent sentinel node navigation surgery (SNNS) for hysterectomy or trachelectomy. METHODS: A total of 139 patients who underwent SNNS using 99mTc phytate between 2009 and 2015 were evaluated. No further lymph node dissection was performed when intraoperative analysis of the sentinel lymph nodes (SLNs) was negative for metastasis. We compared the surgical complications between the SNNS group and 67 matched patients who underwent pelvic lymph node dissection (PLND) after SLN mapping between 2003 and 2008. We also examined the clinical outcomes in the SNNS group. RESULTS: The mean number of detected SLNs was 2.5 per patient. Fourteen of the 139 patients in the SNNS group underwent PLND based on the intraoperative SLN results. The amount of blood loss, the operative time, and the number of perioperative complications were significantly less in the SNNS group than in the matched PLND group. There was no recurrence during a follow-up period ranging from 2 to 88 months (median 40 months) in the SNNS group. CONCLUSIONS: Using SNNS for early-stage cervical cancer is safe and effective and does not increase the recurrence rate. A future multicenter trial is warranted.

Brain-derived neurotrophic factor/tropomyosin-related kinase B signaling pathway contributes to the aggressive behavior of lung squamous cell carcinoma.

The tropomyosin-related kinase (Trk) family consists of TrkA, TrkB, and TrkC, which play essential roles in tumor progression and/or suppression in various cancers. Little is known about the biological significance of the Trk family in human lung squamous cell carcinoma (SCC). Here we investigated the clinical significance of the protein expression of Trk family members in samples from 99 SCC patients, and we explored the relationship between invasion/proliferation activities and Trk expression using lung SCC cell lines to clarify the biological significance of the Trk family in lung SCC. Immunohistochemical high expression of TrkB was significantly correlated with vascular invasion (P=0.004), lymph node metastasis (P<0.001), and advanced stage (P=0.0015). The overall survival of the patients with TrkB-high expression was significantly shorter than those with TrkB-low expression (P=0.0110). TrkA/TrkC expressions were not predictors of poor prognosis. An in vitro assay demonstrated that the inhibition of brain-derived neurotrophic factor (BDNF) (a TrkB ligand) and TrkB by K252a (a Trk inhibitor) or siRNA (BDNF-siRNA, TrkB-siRNA) suppressed the invasion, migration, and proliferative activities of lung SCC cells. The administration of recombinant human BDNF (rhBDNF) enhanced the invasion, migration, and proliferation activities, which were abrogated by K252a. TrkB-siRNA transfection increased the protein expression of E-cadherin and decreased vimentin expressions in lung SCC cells. Matrix metalloproteinase-2 (MMP-2)-mediated gelatin degradations were decreased in lung SCC cells transfected with TrkB-siRNA. Thus, TrkB-high expression is an indicator of poor prognosis in lung SCC, probably due to invasion/proliferation activities promoted by the BDNF/TrkB signaling pathway, which could become a therapeutic target for lung SCC.

Molecular Characteristics of Pancreatic Ductal Adenocarcinomas with High-Grade Pancreatic Intraepithelial Neoplasia (PanIN) Are Different from Those without High-Grade PanIN.

AIMS: We reported that pancreatic ductal adenocarcinomas (PDACs) without high-grade pancreatic intraepithelial neoplasia (PanIN) in the vicinity had worse prognoses than PDACs with high-grade PanIN. However, the molecular characteristics of PDACs with and without high-grade PanIN have not been compared. The aim of this study is to clarify the molecular characteristics of PDACs with and without high-grade PanIN. METHOD AND RESULTS: We reviewed all of a consecutive series of 100 patients with PDACs and divided them into 2 groups: the PDACs with PanIN-2 or PanIN-3 in the background (the PanIN-high group, n = 60) and the PDACs without PanIN-2 or PanIN-3 in the background (the PanIN-low group, n = 40). We evaluated the p53, p16, and SMAD4 expressions in the invasive ductal carcinoma (IDC) components by immunohistochemical staining. KRAS mutation was also analyzed in 80 tumors. The PanIN-low group showed significantly more frequent "high p53 expression" and "loss of SMAD4 expression" than the PanIN-high group (p = 0.048 and p = 0.019, respectively). Loss of p16 expression was not significantly different between the groups. The rate of KRAS wild type was significantly higher in the PanIN-low group than the PanIN-high group (p = 0.024). CONCLUSIONS: Our results demonstrated that the molecular characteristics in the PDACs with high-grade PanIN were different from those in the PDACs without high-grade PanIN. PDACs without high-grade PanIN may develop via a pathway other than the PanIN-carcinoma sequence.

Is Invasive Micropapillary Serous Carcinoma a Low-grade Carcinoma?

"Invasive micropapillary serous carcinoma" has been proposed as a synonym for low-grade serous carcinoma by some expert pathologists. In contrast, Singer and colleagues reported that some serous carcinomas with conspicuous invasive micropapillary pattern (SC-IMPs) can show high-grade nuclear atypia. However, the molecular features of such tumors have not been well documented. The aim of this study was to demonstrate and emphasize the fact that high-grade serous carcinoma confirmed by immunohistochemistry and molecular analysis can show conspicuous invasive micropapillary pattern. We selected 24 "SC-IMPs" and investigated: (1) their morphologic features; (2) the immunostaining pattern of p53 protein; and (3) KRAS/BRAF/TP53 gene mutations. The 24 SC-IMPs were subdivided into low-grade and high-grade tumors based primarily on the nuclear atypia, with the mitotic rate used as a secondary feature: low grade (n=5) and high grade (n=19). Low-grade SC-IMPs were characterized by low-mitotic activity, absence of abnormal mitosis, presence of serous borderline tumor, occasional BRAF mutation, and infrequent TP53 mutation. High-grade SC-IMPs were characterized by high-mitotic activity, presence of abnormal mitosis, conventional high-grade serous carcinoma, frequent TP53 mutation, and lack of KRAS/BRAF mutation. We demonstrated that high-grade serous carcinoma confirmed by aberrant p53 immunostaining and molecular analysis can show conspicuous invasive micropapillary pattern, validating Singer and colleague's report. Serous carcinoma with conspicuous invasive micropapillary pattern should not be readily regarded as low-grade serous carcinoma. Nuclear grade is the most important diagnostic feature in the SC-IMPs.

Primary uterine müllerian mucinous borderline tumor (MMBT) associated with adenomyosis: a case report.

Müllerian mucinous borderline tumors (MMBTs) usually arise from the ovary. The present report is the first case of primary uterine MMBTs associated with adenomyosis. A 51-year-old woman was referred to our hospital for a complex cystic and solid 4×3 cm right adnexal mass. She had a history of a left ovarian endometriotic cyst and had undergone a left oophorectomy 2 yr prior. A laparotomy was performed, and the tumor was found to be originating in the posterior wall of the uterus. She underwent a total abdominal hysterectomy, right salpingo-oophorectomy, and left salpingectomy. Microscopically, the solid portion of the tumor contained papillary proliferations of glands, which were covered by a mucinous epithelium with mild to moderate nuclear atypia, accompanied by stromal infiltration of inflammatory cells. Islands of adenomyosis were also observed around the cyst. These pathologic findings were similar to the features of ovarian MMBT. We diagnosed this tumor as a uterine MMBT, probably arising from adenomyosis.

Dynamics of the neutrophil­to­lymphocyte ratio during lenvatinib treatment for unresectable hepatocellular carcinoma.

Lenvatinib is an approved therapy for advanced hepatocellular carcinoma (HCC). Recently, immune checkpoint inhibitors have been approved as frontline chemotherapies for HCC, and the tumor immune microenvironment (TIME) has been demonstrated to significantly affect HCC treatment. The neutrophil-to-lymphocyte ratio (NLR) is associated with the TIME, and the dynamics of the NLR are associated with prognosis or treatment efficacy in various cancer types. The present study investigated the dynamics of the TIME using the NLR in 101 patients with HCC treated with lenvatinib. Immunostaining for CD8+ tumor-infiltrating lymphocytes (TILs) was also performed in 9 patients who underwent liver tumor biopsy prior to subsequent chemotherapy for progression or discontinuation due to adverse events on lenvatinib treatment. The NLR values measured at the start of treatment (SOT), after 1 month of treatment and after 3 months of treatment were 2.78±2.20, 2.61±1.86 and 2.66±2.36, respectively (P=0.733). Among the patients with no reduction in the initial dose, there was no significant difference between the NLR after 1 month (2.34±0.25) and that at the SOT (2.86±2.33) (P=0.613). In patients who achieved a complete or partial response, the NLR at the time of the best tumor response was 1.65±0.56, which was significantly lower than that at the SOT (2.05±0.78) (P=0.023). In patients who did not respond to lenvatinib, the NLR at the time of disease progression was 3.68±3.19, which was significantly higher than that at the SOT (2.78±1.79) (P=0.043). Overall, 5 out of the 6 patients who did not respond to lenvatinib had low CD8+ TIL counts at disease progression. Although the present study included a limited number of patients, the NLR was associated with the therapeutic effects of lenvatinib. These findings suggest the potential of lenvatinib as an immunomodulator.

Efficacy and histologic frequencies of endoscopic ultrasonography-guided tissue acquisition using conventional fine-needle aspiration needles for gastric subepithelial hypoechoic mass.

Introduction/Purpose: For gastric subepithelial lesions (GSELs) showing a hypoechoic mass (HM) on endoscopic ultrasonography (EUS) imaging, the utility of EUS-guided tissue acquisition using conventional fine-needle aspiration needles (EUS-TA-CFNAN) and the frequency of histological types remain unclear. This study aimed to examine this issue. Methods: This prospective observational study enrolled 291 consecutive patients who underwent EUS-TA-CFNAN for GSELs showing an HM (GSELHM) on EUS imaging. Immunohistochemical analysis was performed for all EUS-TA-CFNAN and surgically resected specimens. The main outcome measures were the technical results of EUS-TA-CFNAN and the frequency of histological types in GSELHM. Results: The endoscopic ultrasound-guided tissue acquisition using conventional fine-needle aspiration needle diagnosis rate for GSELHM was 80.1% (95% confidence interval [CI]: 75.0-84.5, 233/291). It was significantly lower for antrum (P = 0.004) and lesions smaller than 2 cm (P = 0.003). There were no adverse events. The immunohistochemical diagnoses of EUS-TA-CFNAN included 149 cases of gastrointestinal stromal tumour (GIST) (51.2%), 48 cases of leiomyoma (16.5%), 11 cases of schwannoma (3.8%), 8 cases of the ectopic pancreas (2.7%), 5 cases of subepithelial lesion like cancer (1.7%), 12 cases of other lesions (4.1%), and 58 cases of undiagnosable lesions (19.9%). The frequency of malignant or potentially malignant tumour in GSELHM was 55.0% (95% CI: 49.1-60.8, 160/291). Surgery was performed in 149 patients according to the conclusive EUS-TA-CFNAN results, in which the diagnostic accuracy of EUS-TA-CFNAN was 97.3% (95% CI: 94.7-99.9, 145/149). Conclusion: The use of EUS-TA-CFNAN for GSELHMs is safe and accurate. Gastric subepithelial lesions showing a hypoechoic mass have a reasonably high possibility of containing malignant or potentially malignant tumours, including GISTs.

Obstructive Shock Due to a Crushed Left Atrium and Pulmonary Vein by Pulmonary Artery Intimal Sarcoma Successfully Treated with Pulmonary Vein Stenting.

A 46-year-old patient who had undergone right pneumonectomy for pulmonary artery intimal sarcoma presented with hypoxemia. The recurrent sarcoma in the mediastinum revealed external compression to the left pulmonary veins (PVs), leading to obstructive shock and cardiac arrest. Venous artery extracorporeal membrane oxygenation (VA-ECMO) was initiated; however, withdrawal was difficult, and the patient's survival seemed hopeless. However, the patient's condition improved with stenting for the compressed PV; therefore, VA-ECMO was discontinued, and he was discharged on foot. This is the first case report of obstructive shock due to critical PV stenosis caused by compression of a malignant tumor that responded to PV stenting.

High-grade Serous Carcinoma can Show Squamoid Morphology Mimicking True Squamous Differentiation.

Tubo-ovarian high-grade serous carcinoma (HG-SC) and ovarian endometrioid carcinoma (EC) can show overlapping morphologic features, such as glandular and solid patterns. The differential diagnosis of these subtypes is thus sometimes difficult. The existence of "squamous differentiation" tends to lead to a diagnosis of EC rather than HG-SC. We noticed that HG-SC can contain a "squamoid component," but its nature has been poorly investigated. This study was thus established to clarify the nature of this "squamoid component" in HG-SC by investigating its frequency and immunohistochemical features. We reviewed hematoxylin and eosin-stained slides of 237 primary untreated cases of tubo-ovarian HG-SC and identified 16 cases (6.7%) of HG-SC with "squamoid component." An immunohistochemical staining panel (CK5/6, CK14, CK903, p40, p63, WT1, ER, and PgR) was used to analyze all of these 16 cases. We also selected 14 cases of ovarian EC with "squamous differentiation" as a control. The "squamoid component" in HG-SC was completely p40-negative and showed significantly lower expression of CK5/6, CK14, CK903, and p63 than the "squamous differentiation" in EC. The immunophenotype of the "squamoid component" in HG-SC was concordant with the conventional HG-SC component (WT1-positive/ER-positive). Furthermore, all 16 tumors were confirmed to be truly "HG-SC" by the findings of aberrant p53 staining pattern and/or WT1/p16 positivity, and the lack of mismatch repair deficiency and POLE mutation. In conclusion, HG-SC can on rare occasions show a "squamoid component" mimicking "squamous differentiation." However, the "squamoid component" in HG-SC does not represent true "squamous differentiation." The "squamoid component" is one part of the morphologic spectrum of HG-SC, which should be interpreted carefully for the differential diagnosis of HG-SC and EC. An immunohistochemical panel including p40, p53, p16, and WT1 is a useful adjunct to achieve a correct diagnosis.