NKX3.1 Expression in Salivary Gland "Intraductal" Papillary Mucinous Neoplasm: A Low-Grade Subtype of Salivary Gland Mucinous Adenocarcinoma

BACKGROUND

Salivary gland intraductal papillary mucinous neoplasm (SG IPMN) is a recently proposed entity characterized by a papillary-cystic proliferation of mucin-producing cells. Because of overlapping histologic features and a clonal AKT1 p.E17K variant, SG IPMN has been presumed to be a precursor or a low-grade subtype of mucinous adenocarcinoma. NKX3.1 is a tumor suppressor gene located on chromosome 8p and is a known immunohistochemical marker of prostate epithelium and mucinous acinar cells of the intraoral salivary glands.

METHODS

We retrieved 12 SG IPMN cases, and performed histologic and genetic analysis. Given the association of SG IPMN with mucinous acinar cells, we also investigated the performance of NKX3.1 as a marker of this tumor entity.

RESULTS

Diffuse and strong NKX3.1 expression was observed in all SG IPMN cases (12/12, 100%) as well as in normal mucinous acinar cells. In contrast, mucoepidermoid carcinoma and pancreatic IPMN cases as well as normal serous acinar cells were negative for NKX3.1. Genetically, 11 of 12 cases (92%) harbored an AKT1 p.E17K variant. A novel PTEN frameshift deletion (p.G36Dfs*18) was detected in the other single case. At least one of the histologic features implying malignant tumors, such as severe cellular atypia, brisk mitotic activity, high Ki-67 proliferating index, lymphovascular invasion, and lymph node metastasis, was detected in 6 SG IPMN cases (50%).

CONCLUSION

The findings suggest that SG IPMN is a low-grade subtype of mucinous adenocarcinoma which may be derived from mucinous acinar cells of the minor salivary gland.

Yatagarasu: A single-arm, open-label, phase 2 study of apalutamide (APA) plus goserelin (GOS) for patients (pts) with far locally advanced or recurrent/metastatic (fLA/RM) and androgen receptor (AR)-expressing salivary gland carcinoma (SGC)

6079

Background: Overexpression of AR is identified as a potential molecular target of SGC treatment. Combined androgen blockade (CAB) with bicalutamide has been evaluated previously, but the clinical usefulness of CAB with a next generation AR inhibitor has been unclear in SGC. We prospectively assessed the efficacy and safety of APA+GOS for pts with AR-expressing SGC. Methods: Eligible pts had fLA/RM SGC, and AR expression with at least 1% of cell nuclei immunohistochemistry staining positive. Pts were treated with APA 240 mg orally once daily and GOS 3.6 mg subcutaneously once 28 days. Primary endpoint was overall response rate (ORR) by central review according to RECIST v1.1, and a response (complete response [CR] or partial response [PR]) was confirmed by repeat assessments at least 4 weeks after the initial evaluation showing a response. Primary analysis was performed based on first 24 response evaluable (RE) pts who had been observed at least 24 weeks (Primary RE pts). The ORR was tested using exact test based on the binominal distribution, the null hypothesis for ORR of 14% was rejected when at least 8 of the 24 Primary RE pts were responders, and the efficacy was to be declared. Key secondary endpoints included clinical benefit rate (CBR), disease control rate (DCR), duration of response (DOR), and time to response (TTR) in the Primary RE pts, and overall survival (OS), progression free survival (PFS), and safety in the treated pts. Results: Twenty-six of the 31 pts treated with APA+GOS were regarded as RE by central review. For the 24 Primary RE pts, ORR was 25.0% (6/24), while 37.5% (9/24) including unconfirmed PR. Clinical benefit rate and DCR in the Primary RE pts were 50.0% and 70.8%, respectively. At the data cut-off (Apr 28, 2021), 5 of 6 pts with confirmed response were still on protocol treatment. Median PFS and OS in the treated pts were 7.43 months (mos) and not reached, respectively, with the median follow-up period of 8.57 mos. Grade 3 or higher treatment-related adverse events were reported in 4/31 (12.9%) pts, and the events were rash maculo-papular (n=2), anemia (n=1), and leukopenia (n=1). Conclusions: This is the first prospective trial evaluating CAB with APA for AR-expressing SGC. Although this study did not meet the predefined criteria of efficacy, clinically meaningful activity with well-tolerated safety profile of APA+GOS was shown. Clinical trial information: NCT04325828. [Table: see text]

Non-sebaceous lymphadenoma-like mucoepidermoid carcinoma: A case report

Non-sebaceous lymphadenoma is a rare benign salivary gland tumor comprised of non-sebaceous epithelial cells and lymphoid tissue. Although its clinicopathological features have been described, its histogenesis and genetic background have not yet been elucidated. MAML2 rearrangement and the resultant CRTC1/3-MAML2 fusion gene are well-known specific genetic changes in mucoepidermoid carcinoma. Here, we present a case of lymphoepithelial tumor characterized by histomorphology of the non-sebaceous lymphadenoma and CRTC1-MAML2 fusion gene. The patient was an 83-year-old woman with an 8-year history of a solid, well-circumscribed tumor in the parotid gland. Histologically, the tumor was surrounded by thin fibrous connective tissue and was composed of tubular-cystic and solid nests of epithelial cells equally distributed in the lymphoid tissue. The histological features were suggestive of non-sebaceous lymphadenoma. Although the histomorphology was not consistent with mucoepidermoid carcinoma, a diagnosis of non-sebaceous lymphadenoma-like mucoepidermoid carcinoma was made based on the presence of the CRTC1-MAML2 fusion gene. The histological features alone could not establish the diagnosis, and ancillary molecular analysis was required.

The Role of the EZH2 and H3K27me3 Expression as a Predictor of Clinical Outcomes in Salivary Duct Carcinoma Patients: A Large-Series Study With Emphasis on the Relevance to the Combined Androgen Blockade and HER2-Targeted Therapy

Objective

Salivary duct carcinoma (SDC) is a highly aggressive and uncommon tumor arising not only de novo but also in pleomorphic adenoma. Androgen receptor (AR)- and HER2-targeted therapy have recently been introduced for SDC as promising treatment options; however, no predictive biomarkers have yet been established. EZH2 and H3K27me3 are closely linked to the development and progression of various cancers, and EZH2 is also expected to be a desirable therapeutic target. We therefore explored the clinicopathological and prognostic implications of EZH2 and H3K27me3 in a large cohort of SDC patients, focusing on their impact on the therapeutic efficacy of AR- or HER2-targeted therapy.

Materials and Methods

The EZH2 and H3K27me3 immunohistochemical expression and EZH2 Y646 gain-of-function mutation status were examined in 226 SDCs, and the relationship with the clinicopathological factors as well as clinical outcomes were evaluated within the three groups depending on the treatment: AR-targeted (combined androgen blockade with leuprorelin acetate and bicalutamide; 89 cases), HER2-targeted (trastuzumab and docetaxel; 42 cases), and conventional therapy (112 cases).

Results

EZH2 and H3K27me3 were variably immunoreactive in most SDCs. A positive correlation was found between the expression of EZH2 and H3K27me3. The EZH2 expression in the SDC component was significantly higher than that in the pre-existing pleomorphic adenoma component. EZH2 Y646 was not identified in any cases. EZH2-high cases more frequently had an advanced clinical stage and aggressive histological features than EZH2-low cases. An EZH2-high status in patients treated with AR-targeted therapy was associated with a significantly shorter progression-free and overall survival as well as a lower objective response rate and clinical benefit rate. In addition, a H3K27me3-high status in patients treated with AR-targeted therapy was related to a shorter overall survival. Conversely, there was no association between the EZH2 and H3K27me3 expression and the clinical outcomes in the conventional or HER2-targeted therapy groups.

Conclusions

A high expression of EZH2 and H3K27me3 in SDC might be a predictor of a poor efficacy of AR-targeted therapy. Our data provide new insights into the role of EZH2 and H3K27me3 in therapeutic strategies for SDC.

Hypercalcemia associated with dysgerminoma and elevation of calcitriol: A case report and review of the literature

We report on the case of a patient with dysgerminoma, a rare germ cell tumor, which showed hypercalcemia with an elevation of 1α,25-dihydroxycholecalciferol (calcitriol). A 27-year-old nulliparous woman presented with hypercalcemia during the examination of a right ovarian tumor with an elevation of calcitriol, lactate dehydrogenase, and alkaline phosphatase. Fractional excretion of calcium was elevated, and intact parathyroid hormone was suppressed. After undergoing right salpingo-oophorectomy, the patient’s serum calcium and calcitriol returned to the normal range within a week. A literature search was conducted on the topic by reviewing databases for dysgerminoma showing hypercalcemia. We identified 14 patients from the literature and performed a pooled analysis, including the results of our case. However, most cases lack data that can help investigate the potential association between parathyroid hormone, parathyroid hormone-related protein, calcitriol, and phosphorus in hypercalcemia. Thus, more case reports that include additional information are required to fully elucidate the mechanism of hypercalcemia associated with dysgerminoma.

Prediction of non-muscle invasive bladder cancer recurrence using machine learning of quantitative nuclear features

Non-muscle invasive bladder cancer (NMIBC) generally has a good prognosis; however, recurrence after transurethral resection (TUR), the standard primary treatment, is a major problem. Clinical management after TUR has been based on risk classification using clinicopathological factors, but these classifications are not complete. In this study, we attempted to predict early recurrence of NMIBC based on machine learning of quantitative morphological features. In general, structural, cellular, and nuclear atypia are evaluated to determine cancer atypia. However, since it is difficult to accurately quantify structural atypia from TUR specimens, in this study, we used only nuclear atypia and analyzed it using feature extraction followed by classification using Support Vector Machine and Random Forest machine learning algorithms. For the analysis, 125 patients diagnosed with NMIBC were used; data from 95 patients were randomly selected for the training set, and data from 30 patients were randomly selected for the test set. The results showed that the support vector machine-based model predicted recurrence within 2 years after TUR with a probability of 90% and the random forest-based model with probability of 86.7%. In the future, the system can be used to objectively predict NMIBC recurrence after TUR.

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and the Japanese Society of Clinical Cytology: An Extensive Study Containing More Benign Lesions

INTRODUCTION

The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the "neoplastic, benign neoplasm, and low-grade carcinoma" category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system.

METHODS

We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system.

RESULTS

The interobserver agreement was moderate in the JLCS-JSCC (k = 0.499) and PSC (k = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into "negative" or "atypical" by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as "suspicious" or "malignant" by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system.

CONCLUSIONS

The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice.

Efficacy of the Franseen needle for diagnosing gastrointestinal submucosal lesions including small tumors

Background and Objectives:

Several studies have demonstrated that EUS-guided fine-needle biopsy (EUS-FNB) is useful for diagnosing gastrointestinal subepithelial lesions (GI SELs). However, there is limited evidence regarding the use of Franseen needles during EUS-FNB for patients with GI SELs. In addition, the optimal approach for diagnosing small SELs is unclear. This study aimed to evaluate whether EUS-FNB using a Franseen needle was effective for diagnosing GI SELs, including small lesions.

Methods:

Between January 2013 and January 2020, 150 consecutive patients with GI SELs underwent EUS-FNA/FNB to achieve a histological diagnosis. Eighty-six consecutive patients who underwent EUS-FNB using a Franseen needle were compared to 64 patients who underwent EUS-FNA using a conventional needle.

Results:

The diagnostic yield was significantly higher using a Franseen needle than using a conventional needle (85% vs. 75%, P = 0.006). Furthermore, in cases with SELs that were <20 mm, the diagnostic yield was significantly higher using a Franseen needle than using a conventional needle (81% vs. 45%; P = 0.003). Multivariate analysis revealed that obtaining a sufficient diagnostic sample was independently predicted by Franseen needle use (adjusted odds ratio: 2.8, 95% confidence interval: 1.2–6.3; P = 0.01) and tumor size of >20 mm (adjusted odds ratio: 3.4, 95% confidence interval: 1.4–8.2; P = 0.006).

Conclusion:

Even when attempting to diagnose small GI SELs, EUS-FNB using a Franseen needle appears to provide a more efficient acquisition of true histological core tissue than using a conventional needle.

Microsecretory Adenocarcinoma of Salivary Glands: An Expanded Series of 24 Cases

Microsecretory adenocarcinoma (MSA) is a recently described salivary gland tumor with a characteristic histologic and immunophenotypic profile and recurrent MEF2C-SS18 fusions. Because only six cases of MSA have been published, its complete clinicopathologic spectrum is unclear, and its biologic behavior has not been documented. Here, we present an updated and expanded experience of 24 MSA cases. All cases of MSA were obtained from the authors' files. Immunohistochemistry for S100, SOX10, p63, p40, SMA, calponin, and mammaglobin was performed. Molecular analysis was performed by targeted RNA sequencing, SS18 break apart fluorescence in situ hybridization, and/or reverse transcriptase polymerase chain reaction for MEF2C-SS18 fusion. Clinical follow-up was obtained from medical records. A total of 24 MSA cases were collected, from 13 women and 11 men, ranging from 17 to 83 years (mean 49.5 years). The vast majority (23 of 24) arose in the oral cavity, with the palate (n = 14) and buccal mucosa (n = 6) as the most frequent subsites. Tumors showed consistent histologic features including: (1) microcystic tubules, (2) flattened intercalated duct-like cells, (3) monotonous oval hyperchromatic nuclei, (4) abundant basophilic luminal secretions, (5) fibromyxoid stroma, and (6) circumscribed borders with subtle infiltration. The tumors were very consistently positive for S100 (24 of 24), p63 (24 of 24), and SOX10 (14 of 14) and negative for p40 (0 of 21), calponin (0 of 12) and mammaglobin (0 of 16), while SMA (4 of 20) was variable. MEF2C-SS18 fusion was demonstrated in 21 of 24 cases; in the remaining 3 cases with insufficient RNA, SS18 break apart FISH was positive. Treatment information was available in 17 cases, all of which were managed with surgery only. In 14 cases with follow-up (1-216 months, mean 30), no cases recurred or metastasized. MSA is a distinct salivary gland neoplasm with remarkably consistent clinical, histologic, immunophenotypic, and genetic features that generally behaves in an indolent manner following surgery alone. These observations solidify MSA as a unique, low-grade salivary gland carcinoma that warrants inclusion in the next version of the WHO classification of head and neck tumors.

Histopathological characteristics of cervical extensor tissue in patients with dropped head syndrome

Background

To date, the histopathologic characteristics of dropped head syndrome (DHS) have not been reported sufficiently. The present study investigates the histopathology of biopsy specimens from the cervical paravertebral region in patients with DHS.

Methods

Histopathological parameters were evaluated in biopsy specimens of the cervical paravertebral soft tissue from 15 patients with DHS.

Results

Among the 15 cases of DHS examined, skeletal muscle was identified in 7 cases, all of which showed necrosis, microvessel proliferation and atrophy. The ligament was identified in 12 cases, 8 of which showed degeneration. The lag time between the onset of symptoms and the performance of a biopsy in all 8 cases, which showed degeneration was over 3 months. Microvessel proliferation in the ligament was observed in 1 of the 4 cases, in which the lag time between the onset of symptoms and the performance of a biopsy was less than 3 months (acute or subacute phase), and in 7 of the 8 cases, in which the lag time between the symptoms and the performance of a biopsy was over 3 months (chronic phase). Chronic inflammation in the ligament was identified in 1 of the 12 cases.

Conclusions

The identification of necrosis, microvessel proliferation, and atrophy in the skeletal muscle of patients with DHS and the presence of ligament degeneration and microvessel proliferation in the chronic but not acute or subacute phases may suggest that persistent skeletal muscle damage of the cervical paravertebral region causes subsequent ligament damage in patients with DHS.

Expression of L-type amino acid transporter 1 is a poor prognostic factor for Non-Hodgkin's lymphoma

L-type neutral amino acid transporter 1 (LAT1) is a heterodimeric membrane transport protein involved in neutral amino acid transport. LAT1 is highly expressed in various malignant solid tumors and plays an essential role in cell proliferation. However, its role in malignant lymphoma remains unknown. Here, we evaluated LAT1 expression level in tissues from 138 patients with Non-Hodgkin lymphoma (NHL). Overexpression of LAT1 was confirmed in all types of NHL and we found that there is a significant correlation between the level of LAT1 expression and lymphoma grade. The LAT1 expression was higher in aggressive types of lymphomas when compared with static types of lymphomas, suggesting that active tumor proliferation requires nutrient uptake via LAT1. The expression level of LAT1 was inversely correlated with patients’ survival span. Furthermore, pharmacological inhibition of LAT1 by a specific inhibitor JPH203 inhibits lymphoma cell growth. In conclusion, our study demonstrated that LAT1 expression can be used as a prognostic marker for patients with NHL and targeting LAT1 by JPH203 can be a novel therapeutic modality for NHL.

Sarcopenia at the infrahyoid level as a prognostic factor in patients with advanced-stage non-virus-related head and neck carcinoma

PURPOSE

The purpose of this study was to assess whether the infrahyoid skeletal muscle index (IHSMI) can be used instead of the L3 skeletal muscle index (L3SMI) to define sarcopenia and predict prognosis in patients with locally advanced head and neck squamous cell carcinoma (LHNSCC).

METHODS

Patients treated for LHNSCC between January 2009 and April 2018 were assessed. The muscular area at the L3 transverse process and infrahyoid was contoured on absorption-corrected computed tomography prior to treatment. Sarcopenia based on L3SMI (S-L) was defined as values of < 52.4 cm²/m² for men and < 38.5 cm²/m² for women. Sarcopenia based on IHSMI (S-I) was determined via receiver operating curve analysis. Overall survival (OS) and cause-specific survival (CSS) curves were constructed using the Kaplan-Meier method.

RESULTS

In total, 101 patients were analyzed. The median follow-up period was 19 months (range 3-101 month). S-L and S-I were identified in 74 (73.3%) and 56 patients (55.4%), respectively. The 5-year OS rate did not differ between patients with and without S-L (64.9% vs. 79.2%, p = 0.635), whereas the rate was lower in patients with S-I than without S-I (57.1% vs. 93.0%, p = 0.006). Similarly, the 5-year CSS rate did not differ between patients with and without S-L (77.0% vs. 82.3%, p = 0.523), but the rate was lower in patients with S-I (61.2% vs. 93.0%, p = 0.02).

CONCLUSION

Pretreatment S-I, but not S-L, was a good predictor of OS and CSS in patients with LHNSCC.

Salivary mucoepidermoid carcinoma: Histological variants, grading systems, CRTC1/3-MAML2 fusions, and clinicopathological features

AIM

To investigate the histological diversity of salivary mucoepidermoid carcinoma (MEC), its clinicopathological features, and its associations with CRTC1/3-MAML2 fusions.

METHODS

Salivary MEC cases (n=177) were examined for CRTC1/3-MAML2, histological variants were classified, and tumors were graded according to four different grading systems. Adverse histological features considered unusual in MEC were also investigated.

RESULTS

Of the 177 MEC cases, 110 were positive for CRTC1/3-MAML2. The classical variant was most frequent in the fusion-positive, fusion-negative, and all case groups. Clear/oncocytic variant was the second most frequent in the fusion-positive and total case groups. Oncocytic, Warthin-like, and spindle variants were recognized in the fusion-positive group only. Clear cell, sclerosing, mucinous, and central variants were recorded in both fusion-positive and fusion-negative groups. No case was classified as a ciliated variant, as a mucoacinar variant, or as a high-grade transformation. Compared with the classical variant, non-classical variants were characterized by frequent CRTC1/3-MAML2 fusions and a lower clinical stage in all cases. Of four histological features considered unusual in MEC, marked nuclear atypia, frequent mitoses (>10/10HPFs), and extensive necrosis were found independently of the fusion status, and accounted for 3-5% of all cases. However, none of the cases showed overt keratinization. On comparison, the AFIP and modified Healey grading systems downgraded tumors, the Brandwein system upgraded tumors, and the Memorial Sloan Kettering system provided a moderate means of assessment.

CONCLUSION

Recognition of the histological diversity of MEC, its clinicopathological features, and its associations with CRTC1/3-MAML2 fusions is helpful for an accurate diagnosis of this carcinoma.

Mucoepidermoid carcinoma of the lacrimal gland in a patient with the CRTC1-MAML2 fusion gene

Mucoepidermoid carcinoma (MEC) of the lacrimal gland (LG) is a rare entity. A 47-year-old woman was aware of periorbital swelling for 3 months. At presentation, the patient showed periorbital swelling in the right eye. CT scan showed an isodense mass in the anterior superolateral part of the orbit. MRI delineated the mass as enhancing, extra-conal tumor appearing isointense on T1-weighted sequences, and to be of mixed intensity on T2-weighted sequences. The tumor was totally resected. Microscopically, the tumor tissue was comprised of squamous, epithelioid cells, and cells with plump and clear cytoplasm. Necrosis, neural invasion, or mitotic figures were not observed. Immunohistochemical examination revealed intense staining for cytokeratin 7. A subset of the cells was positively stained with periodic acid-Schiff and mucicarmine stains. Genetic analysis revealed the presence of the CRTC1-MAML2 fusion. The CRTC1-MAML2 fusion may be a useful indicator for the prognosis and planning of adjuvant therapy.

Vitreoretinal lymphoma occurring after systemic chemotherapy for primary conjunctival diffuse large B cell lymphoma: A case report

INTRODUCTION

Ocular adnexal lymphoma and vitreoretinal lymphoma are rare forms of non-Hodgkin lymphoma. They are regarded as distinct disease entities due to the differences in molecular mechanism, management, and outcome. We present a rare case of conjunctival diffuse large B cell lymphoma (DLBCL) that developed to vitreoretinal lymphoma after systemic chemotherapy.

PATIENT CONCERNS

A 60-year-old man presented with a left salmon-colored conjunctival mass.

DIAGNOSIS

A biopsy was performed, and histopathologic examination showed DLBCL. Immunohistochemical staining was positive for CD20 with increased κ to λ light chain ratio.

INTERVENTIONS

Bone marrow biopsy also revealed DLBCL. Gallium-67 scintigraphy showed abnormal uptake only in the left orbital lesion. Ann Arbor stage was estimated as IV. The patient underwent systemic combination chemotherapy and immunotherapy.

OUTCOMES

Four months after the last course of chemotherapy, primary conjunctival DLBCL relapsed, manifesting vitreous opacity. Diagnostic vitrectomy confirmed a diagnosis of vitreoretinal lymphoma.

LESSONS

Conjunctival DLBCL and vitreoretinal lymphoma are both DLBCL. After systemic chemotherapy for conjunctival DLBCL, the lymphoma may relapse in intraocular sites as secondary vitreoretinal lymphoma.

Spontaneous regression of malignant lymphoma of the maxillary gingiva following biopsy

A case of spontaneous regression of malignant lymphoma of the maxillary gingiva following a biopsy is reported. An 84-year-old man was referred to the hospital with chief complaints of swelling of the anterior maxillary gingiva. A non-tender swelling with an ulcer was observed. There was no abnormal bone resorption in the anterior maxillary region and no swelling of the cervical lymph nodes. A biopsy was performed, and the patient was diagnosed with diffuse large B-cell lymphoma. The lesion regressed spontaneously 3 weeks after the initial biopsy. Two years have passed since the spontaneous regression and no recurrence has been observed. If malignant lymphoma regresses on biopsy, observation is considered to be sufficient.

A multi-institutional study of salivary gland cytopathology: Application of the Milan System for Reporting Salivary Gland Cytopathology in Japan

Background

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a risk‐stratification reporting system that was introduced in 2018. The objective of this multi‐institutional study was to evaluate the utility of the MSRSGC in Japan.

Methods

In total, 1608 fine‐needle aspiration samples with matching histologic diagnoses were retrieved from 12 large institutions in Japan. The diagnostic categories of the MSRSGC were assigned prospectively or retrospectively, and the results were compared with the histologic diagnoses.

Results

The cases were classified as follows: nondiagnostic, 18.1%; non‐neoplastic, 4.1%; atypia of undetermined significance, 11.5%; neoplasm‐benign, 43.7%; salivary gland neoplasm of uncertain malignant potential, 9.6%; suspicious for malignancy, 3.6%; and malignant, 9.4%. The risk of neoplasm and the risk of malignancy in each MSRSGC category were as follows: nondiagnostic, 72.9% and 13.4%, respectively; non‐neoplastic, 15.2% and 9.1%, respectively; atypia of undetermined significance, 77.9% and 24.9%, respectively; neoplasm‐benign, 99% and 1.8%, respectively; salivary gland neoplasm of uncertain malignant potential, 94.8% and 37%, respectively; suspicious for malignancy, 100% and 89.7%, respectively; and malignant, 100% and 99.3%, respectively. The accuracy of the MSRSGC for diagnosing neoplasms was 97.8%, and its accuracy for diagnosing malignancy was 97.3%. Institutions that used Romanowsky‐stained preparations had lower nondiagnostic rates and lower risks of neoplasm and malignancy in the non‐neoplastic category.

Conclusions

The MSRSGC is useful for risk stratification and quality control. Widespread use of the MSRSGC would improve the accuracy of salivary gland cytology and lead to better patient care in Japan.

This is the first multi‐institutional study of a large‐scale application of the Milan System for Reporting Salivary Gland Cytopathology in Japan. It demonstrates the usefulness of the Milan system in the diagnosis of salivary gland lesions and for the quality control of salivary gland cytology results.

Structural changes in renal arterioles are closely associated with central hemodynamic parameters in patients with renal disease

Although central hemodynamics are known to be closely associated with microvascular damage, their association with lesions in the small renal arteries has not yet been fully clarified. We focused on arterioles in renal biopsy specimens and analyzed whether their structural changes were associated with noninvasive vascular function parameters, including central blood pressure (BP) and brachial-ankle pulse wave velocity (baPWV). Forty-four nondiabetic patients (18-50 years of age) with preserved renal function underwent renal biopsy. Wall thickening of arterioles was analyzed based on the media/diameter ratio, and hyalinosis was analyzed by semiquantitative grading. Associations of these indexes (arteriolar wall remodeling grade index (RG index) and arteriolar hyalinosis index (Hyl index)) with clinical variables were analyzed. Multiple regression analyses demonstrated that the RG index was significantly associated with central systolic BP (β = 0.97, p = 0.009), serum cystatin C-based estimated glomerular filtration rate (β = -0.36, p = 0.04), and high-density lipoprotein cholesterol levels (β = -0.37, p = 0.02). The Hyl index was significantly associated with baPWV (β = 0.75, p = 0.01). Our results indicate that aortic stiffness and abnormal central hemodynamics are closely associated with renal microvascular damage in young to middle-aged, nondiabetic kidney disease patients with preserved renal function.

Relationship between the aortic root Z-score and degree of translamellar mucoid extracellular matrix accumulation

PURPOSES

A retrospective analysis was performed to compare the pathological findings and aortic root Z-score in patients with and without connective tissue disease (CTD).

METHODS

Twenty-two patients {47.5 [15-85] years old, 18 males} underwent surgery for aortic root dilatation without aortic dissection: 10 {40 [16-59] years old} with CTD and 12 {57.5 [15-85] years old} without CTD (non-CTD; p = 0.049). Systemic hypertension (p = 0.043) and the degree of preoperative aortic regurgitation (p = 0.017) were higher in the non-CTD patients than in the CTD patients.

RESULTS

The diameters of the sinotubular junction (STJ) (p = 0.048) and ascending aorta (Asc.Ao.) (p = 0.020) and the Z-scores of the STJ (p = 0.027) and Asc.Ao. (p = 0.009) were significantly higher in the non-CTD patients than in the CTD patients. The degree of translamellar mucoid extracellular matrix accumulation (T-MEMA) of the Asc.Ao. was significantly higher in the non-CTD patients than in the CTD patients (p = 0.037) and was significantly correlated with the Z-scores of the aorta (R = 0.746, p < 0.01 in the sinus of Valsalva and R = 0.382, p = 0.031 in the Asc.Ao.), although there was no significant correlation between the diameter of the STJ and that of Asc.Ao.

CONCLUSIONS

In non-CTD patients, not only the aortic root but also Asc.Ao. tended to dilate with age, and a significant correlation between the Z-scores of the aorta root and the Asc.Ao. and the degrees of T-MEMA was observed.

Increased Plasma Levels of Myosin Heavy Chain 11 Is Associated with Atherosclerosis

Many studies have revealed numerous potential biomarkers for atherosclerosis, but tissue-specific biomarkers are still needed. Recent lineage-tracing studies revealed that smooth muscle cells (SMCs) contribute substantially to plaque formation, and the loss of SMCs causes plaque vulnerability. We investigated the association of SMC-specific myosin heavy chain 11 (myosin-11) with atherosclerosis. Forty-five patients with atherosclerosis and 34 control subjects were recruited into our study. In the atherosclerosis patients, 35 patients had either coronary artery disease (CAD) or peripheral artery disease (PAD), and 10 had both CAD and PAD. Coronary arteries isolated from five patients were subjected to histological study. Circulating myosin-11 levels were higher in the CAD or PAD group than in controls. The area under the receiver operating characteristic curve of myosin-11 was 0.954. Circulating myosin-11 levels in the CAD and PAD group were higher than in the CAD or PAD group, while high-sensitivity C-reactive protein concentrations did not differ between these groups. Multinomial logistic regression analyses showed a significant association of myosin-11 levels with the presence of multiple atherosclerotic regions. Myosin-11 was expressed in the medial layer of human atherosclerotic lesions where apoptosis elevated. Circulating myosin-11 levels may be useful for detecting spatial expansion of atherosclerotic regions.

Predictive and Prognostic Biomarker Identification in a Large Cohort of Androgen Receptor-Positive Salivary Duct Carcinoma Patients Scheduled for Combined Androgen Blockade

Patients suffering from recurrent or metastatic (R/M) salivary duct carcinoma (SDC) are often treated with combined androgen blockade (CAB). However, CAB frequently fails, resulting in a worse prognosis. Therefore, biomarkers that can predict treatment failure are urgently needed. mRNA from 76 R/M androgen receptor (AR)-positive SDC patients treated with leuprorelin acetate combined with bicalutamide was extracted from pre-treatment tumor specimens. AR, Notch, MAPK, TGFβ, estrogen receptor (ER), Hedgehog (HH), and PI3K signaling pathway activity scores (PAS) were determined based on the expression levels of target genes. Additionally, 5-alpha reductase type 1 (SRD5A1) expression was determined. These markers were related to clinical benefit (complete/partial response or stable disease ≥6 months) and progression-free and overall survival (PFS/OS). SRD5A1 expression had the highest general predictive value for clinical benefit and positive predictive value (PPV: 85.7%). AR PAS had the highest negative predictive value (NPV: 93.3%). The fitting of a multivariable model led to the identification of SRD5A1, TGFβ, and Notch PAS as the most predictive combination. High AR, high Notch, high ER, low HH PAS, and high SRD5A1 expression were also of prognostic importance regarding PFS and SRD5A1 expression levels for OS. AR, Notch PAS, and SRD5A1 expression have the potential to predict the clinical benefit of CAB treatment in SDC patients. SRD5A1 expression can identify patients that will and AR PAS patients that will not experience clinical benefit (85.7% and 93.3% for PPV and NPV, respectively). The predictive potential of SRD5A1 expression forms a rational basis for including SRD5A1-inhibitors in SDC patients' treatment.

The Diagnostic Utility of RAS Q61R Mutation-specific Immunohistochemistry in Epithelial-Myoepithelial Carcinoma

Epithelial-myoepithelial carcinoma (EMC) is a rare salivary gland cancer characterized by biphasic tubular structures composed of inner ductal and outer clear myoepithelial cells. Because of its histologic variety and overlap of histologic features with other salivary gland tumors, there are broad differential diagnoses. The HRAS Q61R mutation has been reported to be frequent in and specific to EMC. We evaluated the usefulness of RAS Q61R mutant-specific immunohistochemical (IHC) staining for detecting this genetic alteration in EMC. We investigated 83 EMC cases and 66 cases of salivary gland tumors with an EMC-like component, including pleomorphic adenoma, adenoid cystic carcinoma, basal cell adenoma/adenocarcinoma, and myoepithelial carcinoma. Sanger sequencing was performed for HRAS, KRAS, and NRAS. The diffuse and membranous/cytoplasmic RAS Q61R IHC expression was observed in 65% of EMC cases, in which all cases harbored the HRAS Q61R mutation. IHC-positive cases were present only in de novo EMCs (54/76 cases, 71%) but not in EMCs ex pleomorphic adenoma. The immunoreactivity was almost always restricted to the myoepithelial cells. Conversely, all EMC cases lacking the HRAS Q61R mutation were negative on IHC. In addition, only 3% of EMC-like tumors showed the abovementioned immunopositivity. None of the cases examined carried KRAS or NRAS mutations. IHC for RAS Q61R is highly sensitive and specific for detecting the HRAS Q61R mutation in EMC. Since significant immunopositivity was almost exclusively identified in nearly two thirds of EMCs but seldom in the histologic mimics, the IHC of RAS Q61R is a useful tool for diagnosing EMC in general pathology laboratories.

Neuroendocrine carcinoma of the common bile duct associated with congenital bile duct dilatation: a case report

Background

Cholangiocarcinoma is frequently observed in patients with congenital bile duct dilatation (CBDD). Most cholangiocarcinomas are adenocarcinomas. Other types, especially neuroendocrine carcinomas (NECs), are rare. To the best of our knowledge, this is the third reported case of an NEC of the common bile duct associated with CBDD and the first to receive adjuvant chemotherapy for advanced disease.

Case presentation

A 29-year-old woman presented with upper abdominal pain. Preoperative imaging indicated marked dilatation of the common bile duct and a tumor in the middle portion of the common bile duct. She was suspected of having distal cholangiocarcinoma associated with CBDD and underwent pylorus-preserving pancreaticoduodenectomy. Pathological and immunohistological findings led to a final diagnosis of large-cell NEC (pT3aN1M0 pStageIIB). The postoperative course was uneventful, and she was administered cisplatin and irinotecan every 4 weeks (four cycles) as adjuvant chemotherapy. She has remained recurrence-free for 16 months.

Conclusions

NEC might be a differential diagnosis in cases of cholangial tumor associated with congenital bile duct dilatation. This presentation is rare and valuable, and to establish better treatment for NEC, further reports are necessary.