PD-L1 expression, tumor-infiltrating lymphocytes, mismatch repair deficiency, EGFR alteration and HPV infection in sinonasal squamous cell carcinoma

The antitumor efficacies of immune checkpoint inhibitors (ICIs) and the usefulness of potential predictive markers such as programmed death-ligand 1 (PD-L1) expression, density of tumor-infiltrating lymphocytes (TILs) and microsatellite instability (MSI) in sinonasal squamous cell carcinoma (SNSCC) have not been fully elucidated. We retrospectively analyzed 131 SNSCCs with immunohistochemistry for PD-L1 expression, TIL subpopulations and loss of mismatch repair (MMR) proteins as a surrogate for MSI-high. We also comprehensively evaluated the mutual relationships among these immuno-markers, high-risk human papillomavirus (HPV) infection, epidermal growth factor receptor (EGFR) gene status, and KRAS mutation. PD-L1 expression (tumor proportion score ≥ 1%) was detected in 60 (45.8%) SNSCC cases and was significantly associated with worse overall survival (OS) (p = 0.0240). High density of cluster of differentiation 8 (CD8)-positive TILs was significantly associated with better progression-free survival (PFS) (p = 0.0368), and high density of forkhead box protein P3-positive TILs was significantly associated with better PFS and OS (p = 0.0007 and 0.0143, respectively). With respect to the combination of CD8 + TIL and PD-L1 expression, the high-CD8/PD-L1-negative group showed the most favorable prognosis, whereas the low-CD8/PD-L1-positive group showed the worst prognosis. MMR loss was detected in 3 (2.3%) of the 131 cases. HPV infection (6.1%), EGFR mutation (14.5%), EGFR copy number gain (26%), and MMR loss were essentially mutually exclusive; patients in these molecular groups showed significant differences in prognosis but not in the degree of PD-L1 expression or TILs. Among the nine ICI-treated patients, three (33.3%) were responders, and the EGFR-wild type cases (n = 7) showed better clinical responses to an ICI compared to the EGFR-mutant cases (n = 2). Among the patients with residual/recurrent EGFR-wild type tumors (n = 43), ICI treatment significantly improved OS (p = 0.0281). The results suggest that the evaluation of immuno-markers and molecular subclassification may be helpful for prognostic prediction and selecting an individualized therapeutic strategy for patients with SNSCC.

Rectal Phenotype of Perianal Paget Disease: Rare Concomitant Phenomena

AIM

Classically, 'Paget disease' refers to a distinct histological pattern in breast carcinoma. Here, we review the clinicopathological features of anorectal adenocarcinoma with 'pagetoid' spread.

MATERIALS AND METHODS

Histological and immunohistochemical records for 11 cases of anorectal adenocarcinoma with pagetoid spread among 958 Japanese patients with primary rectal/anal carcinoma were reviewed.

RESULTS

Grossly, nine of 11 cases had areas of invasive carcinoma: Tubular adenocarcinoma in eight and neuroendocrine carcinoma in one. Pagetoid components were positive for cytokeratin 7 in eight cases, cytokeratin 20 and caudal type homeobox 2 in all 11 cases, and p63 in one case, but were negative for estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), gross cystic disease fluid protein-15, and GATA binding protein 3.

CONCLUSION

The prevalence of perianal Paget disease in this series was 1.1%, with two cases of genuine perianal Paget disease with a rectal phenotype without invasive carcinoma. The rectal phenotype of perianal Paget disease may not be associated with HER2 overexpression.

Two case reports of intra-articular nodular fasciitis of the knee confirmed by MYH9-USP6 gene fusion expression

AIM

To describe two cases of intra-articular nodular fasciitis (NF) which developed within the knee joint and were associated with the expression of the MYH9-USP6 gene fusion.

PATIENTS AND METHODS

Two women, 30 and 56 years of age, with no history of joint disease or knee joint trauma, are presented in our cases. We report these cases describing the clinical presentation, assessment, histopathological examination, gene expression, and clinical management.

RESULTS

Both patients presented with knee pain and limitation in the range of flexion. We diagnosed our two cases as intraarticular nodular fasciitis based on histological findings and by the detection of the MYH9-USP6 gene fusion. The transcript of MYH9-USP6 gene fusion was identified by RT-PCR and direct sequencing in both cases.

CONCLUSION

We report the first cases of intra-articular NF involving the knee joint, with identification of a MYH9-USP6 gene fusion by RT-PCR. NF should be considered in the differential diagnosis of intra-articular lesions.

Does the Use of Peripheral Immune-Related Markers Indicate Whether to Administer Pazopanib, Trabectedin, or Eribulin to Advanced Soft Tissue Sarcoma Patients?

Pazopanib, trabectedin, and eribulin are administered for the treatment of soft tissue sarcomas (STSs); however, there is little consensus on which agent should be preferentially used in a clinical setting. This study assessed whether peripheral immune-related markers served as a useful reference when selecting pazopanib, trabectedin, or eribulin. This study included 63 patients who were administered pazopanib, trabectedin, or eribulin for advanced STSs between March 2015 and December 2020. Patients were divided into three groups based on the first drug administered among these three drugs. Differences in overall survival (OS) or progression-free survival (PFS) among the three groups were analyzed. OS showed no significant differences among the drugs administered first. For patients with low neutrophil-to-lymphocyte ratio (NLR), the OS of patients administered pazopanib as the first choice was shorter than the others (hazard ratio [HR] = 9.53, 95% confidence interval [CI] = 1.94–18.13, p = 0.0018). In the low platelet-to-lymphocyte ratio (PLR) subgroup, the OS of the patients administered eribulin for the first choice was longer than that of the others (HR = 0.32, 95%CI = 0.10–0.98, p = 0.046). Therefore, NLR and PLR might be used as prognostic indicators to dictate whether STS patients receive pazopanib, trabectedin, or eribulin.

Clinicopathological and Histopathological Review of Dedifferentiated Liposarcoma: A Comprehensive Study of 123 Primary Tumours

AIMS

Dedifferentiated liposarcoma (DDLS) exhibits varying histopathological features, but their significance for the biological behaviour of this disease has not been fully clarified. This study aimed at elucidating the prognostic factors of DDLS by clinicopathologically reviewing a large case series.

METHODS AND RESULTS

We clinicopathologically reviewed 123 cases of primary de novo DDLS without preoperative treatment, including 81 in the internal trunk (internal DDLS) and 42 in peripheral sites (peripheral DDLS). Univariate and multivariate analyses of their features were also performed for all cases, the internal DDLS group, and the peripheral DDLS group. The results showed that, in all three groups, distant metastasis was significantly associated with shorter overall survival (OS) (univariate analysis, P<0.0001, =0.0011, and 0.0101, respectively), whereas local recurrence showed no significant effect on prognosis. Histopathologically, high mitotic count and the presence of round tumour cells were significantly associated with shorter OS in multivariate analysis of the internal DDLS group (P=0.0022, HR=4.39, 95% CI 1.71-11.28; P=0.0014, HR=7.19, 95% CI 2.14-24.16, respectively). Meanwhile, in the peripheral DDLS group, necrosis and high-grade histological components were significantly associated with shorter OS (univariate analysis, P=0.0068 and 0.0174, respectively).

CONCLUSIONS

The presence of round tumour cells may be one of the histological factors associated with a worse prognosis in DDLS, as previous studies indicated. This work also suggested that distant metastasis may be predictive of prognosis in both internal and peripheral DDLS, instead of local recurrence.

Impact of Nuclear Factor Erythroid 2-Related Factor 2 in Hepatocellular Carcinoma: Cancer Metabolism and Immune Status

We examined phosphorylated nuclear factor erythroid 2–related factor 2 (P‐NRF2) expression in surgically resected primary hepatocellular carcinoma (HCC) and investigated the association of P‐NRF2 expression with clinicopathological features and patient outcome. We also evaluated the relationship among NRF2, cancer metabolism, and programmed death ligand 1 (PD‐L1) expression. In this retrospective study, immunohistochemical staining of P‐NRF2 was performed on the samples of 335 patients who underwent hepatic resection for HCC. Tomography/computed tomography using fluorine‐18 fluorodeoxyglucose was performed, and HCC cell lines after NRF2 knockdown were analyzed by array. We also analyzed the expression of PD‐L1 after hypoxia inducible factor 1α (HIF1A) knockdown in NRF2‐overexpressing HCC cell lines. Samples from 121 patients (36.1%) were positive for P‐NRF2. Positive P‐NRF2 expression was significantly associated with high alpha‐fetoprotein (AFP) expression, a high rate of poor differentiation, and microscopic intrahepatic metastasis. In addition, positive P‐NRF2 expression was an independent predictor for recurrence‐free survival and overall survival. NRF2 regulated glucose transporter 1, hexokinase 2, pyruvate kinase isoenzymes L/R, and phosphoglycerate kinase 1 expression and was related to the maximum standardized uptake value. PD‐L1 protein expression levels were increased through hypoxia‐inducible factor 1α after NRF2 overexpression in HCC cells. Conclusions: Our large cohort study revealed that P‐NRF2 expression in cancer cells was associated with clinical outcome in HCC. Additionally, we found that NRF2 was located upstream of cancer metabolism and tumor immunity.

Pathological review of cardiac amyloidosis using autopsy cases in a single Japanese institution

AIM

Amyloidosis is a systemic or localized disease of protein deposition characterized by amorphous eosinophilic morphology and positivity of Congo Red staining. The typing of amyloidosis is becoming increasingly important because therapeutic agents for each amyloidosis type have been developed. Herein, the authors review the autopsy cases at an institution to reveal the putative Japanese characteristics of each amyloidosis type and evaluate the clinicopathological significance of each type.

MATERIALS AND METHODS

A total of 131 autopsy cases of systemic and localized amyloidosis were retrieved for classification by immunohistochemistry. Immunohistochemistry for transthyretin, amyloid A (AA), immunoglobulin light-chain kappa and lambda, and β2-microglobulin was performed for all cases.

RESULTS

The 131 amyloidosis cases were classified as follows: 71 cases (54.2%) of transthyretin amyloidosis, 32 cases (24.4%) of AA amyloidosis, 8 cases (6.1%) of light-chain amyloidosis, and 5 cases (3.8%) of β2-microglobulin amyloidosis, along with 15 equivocal cases (11.5%). All cases showed myocardial involvement of amyloidosis. Histopathologically, the transthyretin type was significantly associated with the interstitial and nodular patterns, and with the absence of the perivascular and endocardial patterns. The AA type was significantly associated with the perivascular and endocardial patterns, and with the absence of the nodular pattern.

CONCLUSION

The authors revealed the putative characteristics of cardiac amyloidosis in Japan by using autopsy cases. About 90% of amyloidosis cases were successfully classified using only commercially available antibodies.

Carcinoma showing thymus-like differentiation (CASTLE) of the salivary gland: Report of 2 cases of a hitherto under-recognized extrathyroid counterpart

Carcinoma showing thymus-like differentiation (CASTLE) outside the thyroid gland is extremely rare. Here we report two cases of CASTLE of the major salivary gland. The tumors occurred in the parotid gland of a 31-year-old female (Case 1) and in the submandibular gland of a 40-year-old female (Case 2). Both tumors showed a lobulated growth pattern, and were histologically composed of a nested or sheet-like proliferation of carcinoma cells with round- to oval-shaped nuclei, distinct nucleoli and pale eosinophilic cytoplasm, accompanied by various degrees of lymphocytic infiltration. Immunohistochemical staining revealed that the tumors were positive for pan-cytokeratin, p40, CD5, CD117 and bcl-2. In addition, PD-L1 expression was seen in 10-90% of tumor cells. After the initial surgery, Case 1 remained tumor-free for 20 months, while Case 2 suffered lymph node recurrence at 4 months, followed by lung metastasis, which was treated with chemoradiotherapy and anti-PD-1 immune checkpoint inhibitor, resulting in a partial response. The present findings indicate that an extrathyroid counterpart of CASTLE can occur as a primary salivary gland neoplasm. Salivary CASTLEs seem to show a wide range of biological behavior, and long-term follow-up may be needed. Immune checkpoint inhibitor targeting PD-1 might become a promising treatment option in patients with CASTLE; however, further study with a larger number of cases is necessary to establish the optimal therapeutic strategy and prognostic factors for this rare cancer.

The Japanese Society of Pathology Practical Guidelines on the handling of pathological tissue samples for cancer genomic medicine

Clinical cancer genomic testing based on next‐generation sequencing can help select genotype‐matched therapy and provide diagnostic and prognostic information. Pathological tissue from malignant tumors obtained during routine practice are frequently used for genomic testing. This article is aimed to standardize the proper handling of pathological specimens in practice for genomic medicine based on the findings established in “Guidelines on the handling of pathological tissue samples for genomic medicine (in Japanese)” published by The Japanese Society of Pathology (JSP) in 2018. The two‐part practical guidelines are based on empirical data analyses; Part 1 describes the standard preanalytic operating procedures for tissue collection, processing, and storage of formalin‐fixed paraffin‐embedded (FFPE) samples, while Part 2 describes the assessment and selection of FFPE samples appropriate for genomic testing, typically conducted by a pathologist. The guidelines recommend that FFPE sample blocks be used within 3 years from preparation, and the tumor content should be ≥30% (minimum 20%). The empirical data were obtained from clinical studies performed by the JSP in collaboration with leading Japanese cancer genome research projects. The Japanese Ministry of Health, Labour, and Welfare (MHLW) recommended to comply with the JSP practical guidelines in implementing cancer genomic testing under the national health insurance system in over 200 MHLW‐designated core and cooperative cancer genome medicine hospitals in Japan.

Successful management of Wilms tumor accompanied by traumatic renal injury: a case report

When a tumor and trauma coexist, the treatment strategy must be established while considering their interaction. We herein report a 5-month-old girl with Wilms tumor complicated by blunt renal trauma. She was involved in a traffic accident and had hemorrhagic shock due to renal bleeding. We performed hemostasis by transcatheter arterial embolization. Ten days later, we extirpated the potential malignant tumor and left kidney. We were able to complete the surgery without rupture or major bleeding. Postoperative histopathology confirmed Wilms tumor. In the year since she received postoperative chemotherapy, there has been no recurrence. When we were deciding the treatment strategy, we first had to determine how much the renal trauma had affected the tumor staging. The second issue was when to extirpate the tumor after managing the trauma. There are no standard criteria for such situations at present, so we referred to the criteria concerning the bed rest period in cases of traumatic kidney injury and previous case reports and decided to wait over a week from the injury treatment to perform surgery. As a result, we were able to remove the tumor completely without any rupture or major bleeding.

Targeting Pin1 renders pancreatic cancer eradicable by synergizing with immunochemotherapy

Pancreatic ductal adenocarcinoma (PDAC) is characterized by notorious resistance to current therapies attributed to inherent tumor heterogeneity and highly desmoplastic and immunosuppressive tumor microenvironment (TME). Unique proline isomerase Pin1 regulates multiple cancer pathways, but its role in the TME and cancer immunotherapy is unknown. Here, we find that Pin1 is overexpressed both in cancer cells and cancer-associated fibroblasts (CAFs) and correlates with poor survival in PDAC patients. Targeting Pin1 using clinically available drugs induces complete elimination or sustained remissions of aggressive PDAC by synergizing with anti-PD-1 and gemcitabine in diverse model systems. Mechanistically, Pin1 drives the desmoplastic and immunosuppressive TME by acting on CAFs and induces lysosomal degradation of the PD-1 ligand PD-L1 and the gemcitabine transporter ENT1 in cancer cells, besides activating multiple cancer pathways. Thus, Pin1 inhibition simultaneously blocks multiple cancer pathways, disrupts the desmoplastic and immunosuppressive TME, and upregulates PD-L1 and ENT1, rendering PDAC eradicable by immunochemotherapy.

Reevaluation of concurrent acetylcholinesterase and hematoxylin and eosin staining for Hirschsprung's disease

BACKGROUND

Acetylcholinesterase (AChE) histochemistry has been widely performed for the histopathological diagnosis of Hirschsprung's disease (HD). However, we occasionally come across diagnostic difficulties. We conducted concurrent AChE histochemistry and hematoxylin and eosin (HE) staining to validate the ancillary value of this technique.

METHODS

Of 177 patients diagnosed using AChE histochemistry from January 2014 to December 2016, 90 patients underwent formalin-fixed paraffin-embedded HE staining. The histopathological findings and diagnostic abilities were investigated and compared retrospectively.

RESULTS

The sensitivity, specificity, accuracy, and kappa index of AChE histochemistry and HE staining were 94.1%, 100%, 98.9%, and 0.964 and 76.5%, 84.9%, 83.3%, and 0.530, respectively. The specificity, accuracy and kappa index of AChE histochemistry were significantly higher than those of HE staining (P < 0.001, <0.001, and <0.05). Hematoxylin and eosin staining supported the suspected diagnosis of total colon aganglionosis at the initial biopsy; furthermore, HE staining helped confirm the distinct shape of ganglion cells and hypertrophic nerve bundles.

CONCLUSION

We re-confirmed that AChE histochemistry is an excellent method for diagnosing HD. Although the diagnostic ability of HE staining is limited, it has acceptable utility as an ancillary method. Thus, AChE staining is a useful test and it should be performed together with HE staining.

Parosteal osteosarcoma with a manifestation of subperiosteal low-grade central osteosarcoma

We report the peculiar case of a parosteal osteosarcoma arising beneath the periosteum in a 12-year-old boy. He complained of difficulty in left knee flexion. Plain radiography showed a uniformly dense mineralized mass in the bone cortex and parosteal ossified nodules at the metaphysis and diaphysis of the left distal femur. Periosteal reaction was not evident. Uniquely, plain radiography had a smooth outline and revealed gradually thickening mass toward the center. Histologically, the tumor showed a proliferation of spindle-shaped cells with parallel-oriented dense bone trabeculae and hyaline cartilaginous tissue disclosing mild atypia. The periosteum was inverted along the polypoid mass, but there was no periosteum at the top. Immunohistochemically, the spindle cells, including those at the top of the polypoid mass, and cartilaginous cells were positive for MDM2 and CDK4. MDM2 gene amplification was detected in these cells by fluorescence in situ hybridization. Despite the peculiar feature of plain radiography, the lesion was diagnosed as parosteal osteosarcoma. This case report presents a case of parosteal osteosarcoma arising beneath the periosteum, although it is postulated to arise in the outer layer of the periosteum. The unique radiographic findings in this case suggest an association of parosteal osteosarcoma with vigorous bone growth before closure of the growth plate.

Expression of CD44 variant 9 induces chemoresistance of gastric cancer by controlling intracellular reactive oxygen spices accumulation

BACKGROUND

CD44 variant 9 (CD44v9) has been reported to suppress reactive oxygen spices (ROS) in association with antioxidant factors such as glutathione (GSH) and glutathione peroxidase 2 (GPx2), resulting in promoted tumor growth.

METHODS

CD44v9 and GPx2 expression were investigated by immunohistochemistry in resected specimens from 193 gastric cancer (GC) patients without preoperative chemotherapy and in pretreatment biopsy specimens from 29 GC patients with preoperative chemotherapy. We analyzed the relationship between CD44v9 expression and clinicopathological factors, prognosis, and pathological response to chemotherapy. In GC cell lines, we examined the relationship between CD44v9 expression and chemotherapeutic sensitivity.

RESULTS

In patients without preoperative chemotherapy, CD44v9 expression was significantly associated with depth of invasion, lymphatic permeation, vascular invasion, distant metastasis and GPx2 expression. In multivariate analysis, CD44v9 expression was an independent poor prognosis factor for overall survival and recurrence-free survival. In patients with preoperative chemotherapy, CD44v9 expression was significantly associated with worse pathological response and GPx2 expression. In GC cell lines, downregulation of CD44v9 expression enhanced chemotherapeutic sensitivity to 5-fluorouracil with changing GSH and ROS levels.

CONCLUSIONS

CD44v9-positive expression was associated with chemotherapeutic resistance by controlling intracellular accumulated ROS, suggesting that CD44v9 may be a predictive biomarker for chemotherapy in GC.

Successful management to prevent early graft loss due to Seventh-day Syndrome after liver retransplantation: A case report and literature review

Graft loss characterized by sudden deterioration after initial favorable recovery of the allograft function within the first week after liver transplantation was reported as "seventh-day syndrome." The outcome of seventh-day syndrome is extremely poor, and its etiology and management are not still established. We herein reported a seventh-day syndrome case who was successfully managed by immediate desensitization after liver retransplantation and reviewed by English literature. A 19-year-old woman who had underwent the first liver transplantation when she was 2-year-old. She developed graft failure due to chronic rejection and was on the waiting list for retransplantation. An evaluation of panel-reactive antibody showed high positivity, but there were no preformed donor-specific antibodies. Plasma exchange was performed one-time just before retransplantation and the mean fluorescence intensity significantly decreased. The second liver was successfully transplanted, and post-operative course was uneventful. However, on post-operative day 5, her body temperature elevated and thereafter, her liver enzymes dramatically elevated. We immediately started a desensitization consisted of plasma exchange, intravenous immunoglobulin, and anti-CD20 antibody. The peak level of AST and ALT was 5799 IU/L and 3960 IU/L, respectively. The pathological findings of liver biopsy revealed some central venous endotheliitis and massive centrilobular hemorrhagic hepatocellular necrosis. These findings were not typical for antibody-mediated rejection, but the desensitization was effective and liver graft was successfully rescued. The only way to prevent early graft loss due to seventh-day syndrome is thought to be an immediate decision to start intensive desensitization.

CDK4: A Novel Therapeutic Target for Extramammary Paget's Disease

BACKGROUND

The outcome of extramammary Paget's disease (EMPD) is poor when it progresses to metastasis because of the lack of effective systemic therapies. Recently, CDK4-targeted therapy has attracted attention as a potential therapeutic target for some cancers. The aim of this study was to analyze the impact of CDK4 expression on the survival of patients with EMPD.

METHODS

We retrospectively reviewed 110 patients with EMPD. We conducted immunohistochemical analysis of CDK4 and cyclin D1 expression, and assessed the association between their expression and survival.

RESULTS

Most EMPD lesions (108/110, 98.2%) were positive for CDK4 staining and there was a positive correlation between CDK4 expression and cyclin D1 expression (r = 0.54, p < 0.001). Tumor thickness (p = 0.0003) and the presence of regional lymph node metastasis (p = 0.015) were significantly associated with high CDK4 expression. Regarding invasive EMPD, the multivariate analysis did not show the correlation between the expression of CDK4/cyclin D1 and survival outcomes (HR: 3.14, p = 0.14).

CONCLUSION

The overexpression of CDK4 was identified as a major risk factor for disease progression. CDK4-targeted therapy could thus be a novel treatment option for unresectable EMPD.

Effect of the 2013 ASCO-CAP HER2 Testing Guideline on the Management of IHC/HER2 2+ Invasive Breast Cancer

BACKGROUND/AIM

With advances in anti-HER2 treatment and improved prognoses of HER2-positive breast cancer, the American Society of Clinical Oncology and the American Society of Pathologists (ASCO/CAP) have revised the HER2 diagnostic guidelines several times. We examined how to respond clinically to the revisions of the interpretation of the immunohistochemistry (IHC) method.

PATIENTS AND METHODS

We re-evaluated 254 patients diagnosed as HER2 IHC equivocal, who underwent fluorescence in situ hybridization (FISH) before and after the IHC diagnostic criteria update in 2013.

RESULTS

Twenty of 131 (15.3%) IHC equivocal cases by the ASCO/CAP 2007 guideline were IHC score 3+ and one of 20 (0.76%) was negative for FISH. Five of 123 (4.1%) IHC equivocal cases by the ASCO/CAP 2013 guideline were negative for IHC as per the 2007 guideline and four were positive for FISH.

CONCLUSION

After revision of the ASCO/CAP 2013 guideline, 3.3% of HER2-negative cases before the revision should have received anti-HER2 treatment.

Trop2 Expression in Extramammary Paget's Disease and Normal Skin

Extramammary Paget's disease (EMPD) is a rare skin cancer arising in the apocrine gland-rich areas. Most EMPD tumors are dormant, but metastatic lesions are associated with poor outcomes owing to the lack of effective systemic therapies. Trophoblast cell surface antigen 2 (Trop2), a surface glycoprotein, has drawn attention as a potential therapeutic target for solid tumors. Sacituzumab govitecan, an antibody-drug conjugate of Trop2, has recently entered clinical use for the treatment of various solid cancers. However, little is known about the role of Trop2 in EMPD. In this study, we immunohistochemically examined Trop2 expression in 116 EMPD tissue samples and 10 normal skin tissues. In normal skin, Trop2 was expressed in the epidermal keratinocytes, inner root sheaths, and infundibulum/isthmus epithelium of hair follicles, eccrine/apocrine glands, and sebaceous glands. Most EMPD tissues exhibited homogeneous and strong Trop2 expression, and high Trop2 expression was significantly associated with worse disease-free survival (p = 0.0343). These results suggest the potential use of Trop2-targeted therapy for EMPD and improve our understanding of the skin-related adverse effects of current Trop2-targeted therapies such as sacituzumab govitecan.

A case of primary orbital solitary fibrous tumor with lung metastases 41 years after initial treatment

Here, we report a case of an orbital solitary fibrous tumor (SFT) with multiple local recurrences, even after orbital exenteration, and lung metastases after 41 years. The report discusses the clinical and histopathological findings of this case. A 34-year-old female patient with an orbital SFT was treated with orbital exenteration after local resection failed to prevent a recurrence. Ten years later, the patient underwent radiation therapy, followed by two rounds of gamma knife treatment, leading to remission. Forty-one years after the first treatment, the patient, at the age of 75 years, was found to have lung metastases along with orbital recurrence for the eighth time. The patient underwent radiation therapy but died from radiation pneumonitis. Our case emphasizes the need for long-term follow-up of patients with orbital tumors, even after orbital exenteration, to monitor for metastasis.

Impact of Metabolic Activity in Hepatocellular Carcinoma: Association With Immune Status and Vascular Formation

We evaluated the prognostic value of fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in hepatocellular carcinoma (HCC). Their association with programmed death ligand 1 (PD-L1) expression and vascular formation was further investigated. In this retrospective study, using a database of 418 patients who had undergone ¹⁸F-FDG PET/CT before hepatic resection for HCC, immunohistochemical staining of PD-L1, clusters of differentiation (CD) 8, CD68, and CD34 was performed. Patients with a high maximum standardized uptake value (SUVmax) on ¹⁸F-FDG PET/CT showed a significantly worse recurrence-free survival (RFS) (hazard ratio [HR]: 1.500; 95% confidence interval [CI]: 1.088-2.069; P = 0.0133) and overall survival (OS) (HR: 2.259; 95% CI: 1.276-4.000; P = 0.0052) than patients with a low SUVmax. Logistic regression analysis showed that a high SUVmax in HCC was significantly associated with PD-L1-positive expression (odds ratio: 4.407; 95% CI: 2.265-8.575; P < 0.0001). SUVmax values of HCC were associated with intratumoral CD8-positive T-cell counts (P = 0.0044) and CD68-positive macrophage counts (P = 0.0061). Stratification based on SUVmax, PD-L1 expression, and the vessels that encapsulate tumor clusters (VETC) status was also significantly associated with RFS and OS. SUVmax, VETC, and PDL1 expression were independently predictive of survival on multivariable analysis. Conclusion: Our large cohort study showed that a high SUVmax on ¹⁸F-FDG PET/CT is associated with a poor clinical outcome and PD-L1 expression in patients with HCC. Additionally, stratification of patients based on the combination of SUVmax, PD-L1 expression, and the VETC status predicts poor clinical outcome.

Neoantigens elicit T cell responses in breast cancer

Neoantigens are tumour-specific antigens that arise from non-synonymous mutations in tumour cells. However, their effect on immune responses in the tumour microenvironment remains unclear in breast cancer. We performed whole exome and RNA sequencing of 31 fresh breast cancer tissues and neoantigen prediction from non-synonymous single nucleotide variants (nsSNVs) among exonic mutations. Neoantigen profiles were determined by predictive HLA binding affinity (IC₅₀ < 500 nM) and mRNA expression with a read count of ≥ 1. We evaluated the association between neoantigen load and expression levels of immune-related genes. Moreover, using primary tumour cells established from pleural fluid of a breast cancer patient with carcinomatous pleurisy, we induced cytotoxic T lymphocytes (CTLs) by coculturing neoantigen peptide-pulsed dendritic cells (DCs) with autologous peripheral lymphocytes. The functions of CTLs were examined by cytotoxicity and IFN-γ ELISpot assays. Neoantigen load ranged from 6 to 440 (mean, 95) and was positively correlated to the total number of nsSNVs. Although no associations between neoantigen load and mRNA expression of T cell markers were observed, the coculture of neoantigen-pulsed DCs and lymphocytes successfully induced CTLs ex vivo. These results suggest that neoantigen analysis may have utility in developing strategies to elicit T cell responses.

Programmed Death-Ligand 1 Expression and Tumor-Infiltrating Lymphocytes in Temporal Bone Squamous Cell Carcinoma

OBJECTIVES/HYPOTHESIS

The tumor immune microenvironment in temporal bone squamous cell carcinoma (TBSCC), including the programmed death-ligand 1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs), has not been established.

STUDY DESIGN

Retrospective cohort study.

METHODS

We performed immunohistochemistry analyses to retrospectively analyze 123 TBSCC cases for PD-L1 expression and TILs and their prognostic significance. We also evaluated the prognostic correlations between these immunomarkers and the therapeutic responses to chemoradiotherapy (CRT).

RESULTS

PD-L1 expression (≥1%) was detected in 62 (50.4%) TBSCC cases and was significantly associated with worse prognosis: progression-free survival (PFS), P < .0001; overall survival (OS), P = .0009. A high density of CD8⁺ TILs was significantly associated with better prognosis (PFS, P = .0012; OS, P = .0120). In contrast, a high density of Foxp3⁺ TILs tended to be associated with an unfavorable prognosis (PFS, P = .0148; OS, P = .0850). With regard to the tumor microenvironment subtypes defined by CD8⁺ TILs and PD-L1 expression, the CD8^low /PD-L1⁺ group showed significantly worse prognosis. Among the 36 neoadjuvant CRT-treated cases, PD-L1 expression was significantly associated with worse OS (P = .0132). Among the 32 CRT-treated cases without surgery, a high density of CD8⁺ TILs tended to be more highly associated with complete response to CRT compared to a low density of CD8⁺ TILs (P = .0702).

CONCLUSIONS

These results indicate that the evaluation of the tumor immune microenvironment may contribute to the prediction of prognoses and the selection of an individualized therapeutic strategy for patients with TBSCC.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Lymphocyte-C-reactive protein ratio as a prognostic marker associated with the tumor immune microenvironment in intrahepatic cholangiocarcinoma

BACKGROUND

Changes in immune cell and inflammation-associated protein levels, either independently or in combination, are commonly used as prognostic factors for various cancers. The ratio of lymphocyte count to C-reactive protein concentration (lymphocyte-CRP ratio; LCR) is a recently identified prognostic marker for several cancers. Here, we examined the prognostic value of LCR and its relationship to various aspects of the tumor immune microenvironment in patients with intrahepatic cholangiocarcinoma (ICC).

METHODS

This was a single-center, retrospective study of patients who underwent surgical resection for ICC between 1998 and 2018. Patients were dichotomized into high- and low-LCR status groups, and the relationships between LCR status, prognosis, and other clinicopathological characteristics were analyzed. Tumor-infiltrating CD8+ and FOXP3s+ lymphocytes and tumor expression of CD34 and programmed death-ligand 1 were evaluated by immunohistochemical staining of resected tumors.

RESULTS

A total of 78 ICC patients were enrolled and assigned to the high (n = 44)- and low (n = 34)-LCR groups. Compared with the high-LCR group, patients in the low-LCR group had a significantly higher serum CA19-9 level (median 20.6 vs. 77.3 U/mL, P = 0.0017) and larger tumor size (median 3.5 vs. 5.5 cm, P = 0.0018). LCR correlated significantly with tumor microvessel density (r = 0.369, P = 0.0009) and CD8+ T lymphocyte infiltration (r = 0.377, P = 0.0007) but not with FOXP3+ T lymphocyte infiltration or tumor PD-L1 expression. Low-LCR status was significantly associated with worse overall survival by multivariate analysis (P = 0.0348).

CONCLUSIONS

Low-LCR status may reflect a poor anti-tumor immune response and predict worse outcomes in ICC patients.

Clinical significance of signal regulatory protein alpha (SIRPα) expression in esophageal squamous cell carcinoma

Signal regulatory protein alpha (SIRPα) is a type I transmembrane protein that inhibits macrophage phagocytosis of tumor cells upon interaction with CD47, and the CD47‐SIRPα pathway acts as an immune checkpoint factor in cancers. This study aims to clarify the clinical significance of SIRPα expression in esophageal squamous cell carcinoma (ESCC). First, we assessed SIRPα expression using RNA sequencing data of 95 ESCC tissues from The Cancer Genome Atlas (TCGA) and immunohistochemical analytic data from our cohort of 131 patients with ESCC. Next, we investigated the correlation of SIRPα expression with clinicopathological factors, patient survival, infiltration of tumor immune cells, and expression of programmed cell death‐ligand 1 (PD‐L1). Overall survival was significantly poorer with high SIRPα expression than with low expression in both TCGA and our patient cohort (P < .001 and P = .027, respectively). High SIRPα expression was associated with greater depth of tumor invasion (P = .0017). Expression of SIRPα was also significantly correlated with the tumor infiltration of M1 macrophages, M2 macrophages, CD8⁺ T cells, and PD‐L1 expression (P < .001, P < .001, P = .03, and P < .001, respectively). Moreover, patients with SIRPα/PD‐L1 coexpression tended to have a worse prognosis than patients with expression of either protein alone or neither. Taken together, SIRPα indicates poor prognosis in ESCC, possibly through inhibiting macrophage phagocytosis of tumor cells and inducing suppression of antitumor immunity. Signal regulatory protein alpha should be considered as a potential therapeutic target in ESCC, especially if combined with PD‐1‐PD‐L1 blockade.

Prognostic Impact of Vessels that Encapsulate Tumor Cluster (VETC) in Patients who Underwent Liver Transplantation for Hepatocellular Carcinoma

BACKGROUND

There is limited published information about prognostic value of vessels that encapsulate tumor cluster (VETC) based on their involvement with immune cells in hepatocellular carcinoma (HCC). Our goal was to evaluate prognostic impact of VETC in patients who underwent living-donor liver transplantation (LDLT) for HCC, focusing on the involvement of VETC with immune status in tumor microenvironment (TME).

METHODS

Using a database of 150 patients who underwent LDLT for HCC, immunohistochemical staining of CD34 for VETC, angiopoietin-2 (Ang-2), CD3, and CD68, was reviewed with patients' clinicopathological factors.

RESULTS

A strong correlation between VETC pattern and malignant potential in HCC was observed; larger tumor size (P < 0.001), more numbers of tumors (P = 0.003), higher α-fetoprotein levels (P = 0.001), higher des-γ-carboxy prothrombin levels (P = 0.022), microvascular invasion (P < 0.001), and poor differentiation (P = 0.010). Overall survival (OS) of patients with VETC⁽⁺⁾ was significantly lower than those with VETC^(-) (P = 0.021; 5-year OS rates, 72.0% vs. 87.1%). Furthermore, the ratio of CD3⁽⁺⁾ cells was significantly lower in VETC⁽⁺⁾ group (P = 0.001), indicating that VETC activity may be strongly correlated with lymphocyte activity. Moreover, combination status of VETC⁽⁺⁾/CD3^low was an independent risk factor for mortality (hazard ratio 2.760, 95% confidence interval 1.183-6.439, P = 0.019). Additionally, the combination of VETC expression with immune status (low CD3 levels) enabled further classification of patients based on their clinical outcome.

CONCLUSIONS

Our results show the prognostic impact of VETC expression, tumor-infiltrating lymphocytes (TILs), and their combination in the setting of LDLT for HCC, which can be a novel prognostic biomarker for mortality after LDLT.

Histological categorisation of the desmoplastic reaction is a predictor of patient prognosis in oesophageal squamous cell carcinoma

AIMS

Histological categorisation of the desmoplastic reaction (DR) is an independent prognostic factor in colorectal cancer. However, it is unknown whether DR categorisation is predictive of oesophageal squamous cell carcinoma (OSCC) outcomes. This study aimed to evaluate the prognostic value of DR categorisation in OSCC patients.

METHODS AND RESULTS

Data were collected from 118 patients with OSCC who underwent a curative oesophagectomy with T2 or deeper wall invasion. The DR in each tumour was classified as mature, intermediate or immature based on the presence or absence of keloid-like collagen and myxoid stroma. We identified 49 mature DR tumours, 41 intermediate DR tumours and 28 immature DR tumours. The 5-year overall survival (OS) rate was highest in the mature DR group (42.8%), followed by the intermediate DR group (25.0%) and the immature DR group (19.9%) (P = 0.022, log-rank test; P = 0.006, log-rank trend test). The 5-year disease-specific survival (DSS) rate was also highest in the mature DR group (48.5%), followed by the intermediate DR group (30.8%) and the immature DR group (26.8%) (P = 0.031, log-rank test; P = 0.010, log-rank trend test, respectively). Multivariate analysis revealed that an immature DR was an independent poor prognostic factor of OS and DSS (P = 0.002 and P = 0.004).

CONCLUSIONS

DR categorisation of OSCC stroma following oesophagectomy is a useful diagnostic tool and an independent prognostic marker.

The effects of ARID1A mutations on colorectal cancer and associations with PD-L1 expression by stromal cells

Background

ARID1A is a component of the SWI/SNF complex, which controls the accessibility of proteins to DNA. ARID1A mutations are frequently observed in colorectal cancers (CRCs) and have been reported to be associated with high mutational burden and tumor PD‐L1 expression in vitro.

Aim

To clarify the role of ARID1A mutation in CRC.

Method and results

We used next generation sequencing (NGS) and immunohistochemistry on clinically obtained samples. A total of 201 CRC tissues from Niigata University and Niigata Center Hospital were processed by NGS using the CANCERPLEX panel. Immunohistochemistry for ARID1A, PD‐L1, MLH1, and MSH2 was performed on 66 propensity‐matched (33 microsatellite instability‐high [MSI‐H] and 33 microsatellite‐stable [MSS]) cases among 499 cases from Kyushu University. TCGA data were downloaded from cBioPortal. NGS showed significantly more mutations in ARID1A mutated CRCs (p = 0.01), and the trend was stronger for right‐sided CRCs than left‐sided. TCGA data confirmed these findings (p < 0.01). BRAF V600E and ATM mutations were also found at higher frequencies. Immunohistochemistry showed that 30% of MSI‐H CRCs had ARID1A loss, while this was true in only 6% of MSS CRCs. In both MSI‐H and MSS, PD‐L1 expression by stromal cells was enhanced in the ARID1A‐mutant groups (90% vs 39% in MSI‐H, 100% vs 26% in MSS).

Conclusion

We found a higher mutational burden in ARID1A‐mutant CRCs, and IHC study showed that ARID1A loss was correlated with high PD‐L1 expression in stromal cells regardless of MSI status. These data support the idea that mutant ARID1A is a potential biomarker for CRCs.

Quantification of HER family dimers by proximity ligation assay and its clinical evaluation in non-small cell lung cancer patients treated with osimertinib

OBJECTIVES

The epidermal growth factor receptor (EGFR, also known as Her1) is a member of the human epidermal growth factor receptor (HER) family of proteins and a target of tyrosine kinase inhibitors (TKIs) in the treatment of non-small cell lung cancer (NSCLC) positive for activating mutations ofEGFR. Signal transduction by HER family proteins is dependent on their homo- or heterodimerization, but little is known of the relation between the relative proportions of such dimers of Her1 and sensitivity to EGFR-TKIs. We here investigated the feasibility of assessing this relation with the in situ proximity ligation assay (PLA) technique, which is able to detect the interaction of two proteins of interest when they are in close proximity.

MATERIALS AND METHODS

In situ PLA was applied to detect Her1 homodimers and Her1 heterodimers in NSCLC cell lines and tissue specimens positive for EGFR activating mutations.

RESULTS

In situ PLA allowed visualization and quantitative assessment of Her1 homodimers as well as of Her1 heterodimers with Her2, Her3, or Her4 not only in NSCLC cell lines but also in NSCLC tissue specimens obtained from various anatomic sites and by different collection methods. Treatment of NSCLC cell lines with EGFR-TKIs resulted in a decrease in the number of Her1 dimers, with the effect on homodimers being greater than that on heterodimers. A high ratio of Her1 heterodimers to homodimers was associated with poor progression-free survival in NSCLC patients treated with osimertinib.

CONCLUSION

In situ PLA allows the detection of HER family dimers in NSCLC tissue, and quantitative assessment of Her1 homo- and heterodimers may prove informative for prediction of the response of NSCLC patients to EGFR-TKI treatment.

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).

Histological background of dedifferentiated solitary fibrous tumour

AIMS

Dedifferentiation is a histological phenomenon characterised by abrupt transition of histology to a sarcomatous component with high-grade malignant potential in solitary fibrous tumour (SFT). The authors histologically reviewed SFT cases to reveal the histological background of dedifferentiated SFTs.

METHODS

Clinicopathological and histopathological findings of 145 SFT cases were reviewed. Immunohistochemical staining and genetic analysis were also performed.

RESULTS

The non-dedifferentiated components showed a cellular component in 45 of 145 (31%), high mitotic rate (≥4/10 high-powered field) in 12 of 145 (8.2%) tumours, necrosis in 7 of 145 (4.8%) tumours, multinodular growth pattern in 39 of 132 (29.5%) available tumours and intratumoural fibrous septa in 37 of 131 (28.2%). Immunohistochemically, the non-dedifferentiated components were positive for CD34 in 128 of 141 (90.7%), bcl-2 in 101 of 133 (75.9%), nuclear pattern of β-catenin in 64 of 127 (50.3%) and p16 in 22 of 140 (15.7%). Loss of Rb protein expression was detected in 17 of 110 (15.4%) cases. Statistically, cellular component, multinodular structure, p16 overexpression and Rb protein loss were significantly associated with dedifferentiation. Moreover, cellular component and multinodular structure were significantly associated with p16 overexpression and Rb protein loss. All the non-deddifferentiated components showed wild type of p53 expression. The dedifferentiated components of all 10 dedifferentiated tumours presented positivity for p16 in 9 of 10 (90%) and mutational type of p53 in 5 of 10 (50%). Loss of Rb protein expression was detected in 6 of 10 (60%).

CONCLUSIONS

The authors propose that cellular or multinodular transformation may be associated with dedifferentiation. They also suggest that cellular and multinodular transformation may be associated with p16 overexpression and Rb downregulation.

Prognostic implications of the coexisting precursor lesion types in invasive gallbladder cancer

Invasive gallbladder carcinoma (GBC) is preceded by two main types of precursor lesions: intracholecystic papillary-tubular neoplasms (ICPNs) and biliary intraepithelial neoplasias (BilINs). Invasive GBCs with an ICPN component have more favorable prognoses than those without an ICPN component. Some BilINs show a relatively exophytic papillary pattern but do not meet the ICPN criteria; at our institution, we call these papillary neoplasias. To clarify the clinical significance of papillary neoplasia, we herein examined 80 invasive GBCs and classified them into three groups based on the type of preinvasive lesions: those with ICPN (ICPN group, n = 35), those with papillary neoplasia (pap-neoplasia group, n = 13), and those without ICPN/papillary neoplasia (group without ICPN/pap-neoplasia, n = 32). We then compared the prognostic differences and characterized the tumors of each group by determining the immunohistochemical expressions of various biomarkers. The overall survival periods of the ICPN and pap-neoplasia groups were significantly longer than that of the group without ICPN/pap-neoplasia (P < 0.0001, P = 0.0036, respectively). Multivariate analysis revealed that lacking ICPN/papillary neoplasia was independently associated with poor prognosis (P = 0.0007), as were poor differentiation (P = 0.0395), presence of preoperative symptoms (P = 0.0488), and advanced stage (P = 0.0234). Invasive components of the ICPN and pap-neoplasia groups were characterized by higher expressions of p16 and p53 compared with those of the group without ICPN/pap-neoplasia. The prognoses of the invasive GBCs with either papillary neoplasia or ICPN were thus more favorable than those of the invasive GBCs without ICPN/pap-neoplasia. Invasive GBCs with exophytic papillary preinvasive lesions (ICPN and papillary neoplasia) may be biologically different from those without such lesions.

p16 overexpression and Rb loss correlate with high-risk HPV infection in oropharyngeal squamous cell carcinoma

AIMS

p16 is a sensitive surrogate marker for transcriptionally active high-risk human papillomavirus (HR-HPV) infection in oropharyngeal squamous cell carcinoma (OPSCC), but it is not sufficient in all clinical settings.

METHODS AND RESULTS

We examined the p16 and Rb expression status in 177 OPSCC cases by immunohistochemistry and the presence of transcriptionally active HR-HPV infection by mRNA in-situ hybridisation. The 177 cases were divided into p16⁺ /HPV⁺ (n = 105, 59.3%), p16⁺ /HPV^- (n = 8, 4.5%) and p16^- /HPV^- (n = 64, 36.2%) groups. The p16⁺ /HPV^- and p16^- /HPV^- groups had a trend towards worse overall survival (OS) or significantly worse OS than the p16⁺ /HPV⁺ group (n = 105) (P = 0.0610, P = 0.0004, respectively). We divided the Rb status into preserved expression (> 90%, n = 68), partial loss (PL) (10-90%, n = 97) and complete loss (CL) (< 10%, n = 12). Among the HPV-positive cases (n = 105), the Rb pattern was typically PL (n = 97, 92.4%) and rarely CL (n = 8, 7.6%), but never preserved expression (0%). In contrast, among the HPV-negative cases (n = 72), the Rb pattern was typically preserved expression (n = 68, 94.4%) and rarely CL (n = 4, 5.6%), but never PL (0%). Compared to p16 alone, the combination of p16 overexpression and Rb-PL/CL showed equally excellent sensitivity (each 100%) and improved specificity (97.2 versus 88.9%) and positive predictive values (98.1 versus 92.9%).

CONCLUSIONS

These results suggest that the combined use of p16 and Rb immunohistochemistry could be a reliable, cost-effective method to predict HR-HPV infection in OPSCCs; however, HPV specific testing is necessary on inconclusive cases. We propose a diagnostic algorithm for practical use of these markers.

Myxoepithelioid tumour with chordoid features: a clinicopathological, immunohistochemical and genetic study of 14 cases of SMARCB1/INI1-deficient soft-tissue neoplasm

AIMS

Complete loss of SMARCB1/INI1 in soft-tissue tumours such as malignant rhabdoid tumour, epithelioid sarcoma, myoepithelial tumour of soft tissue and extraskeletal myxoid chondrosarcoma is often associated with high-grade malignancy and poor prognosis. The diagnosis is sometimes challenging, owing to histological similarities, so careful differential diagnosis is required. Therefore, soft-tissue tumours with complete SMARCB1/INI1 loss could potentially include an unknown entity.

METHODS AND RESULTS

We analysed 160 cases of SMARCB1/INI1-deficient soft-tissue tumour, and found 14 cases that were not classifiable into already existing categories and had common clinical and histological features. These involved two male and 12 female patients, ranging in age from 20 years to 61 years. The tumours were located in the the puboinguinal region (n = 13) and pelvic cavity (n = 1). Histologically, the tumours showed relatively uniform epithelioid to spindle-shaped cells with myxoid stroma. All tumours showed immunoreactivity for brachyury, epithelial membrane antigen, and progesterone receptor, and 12 of 14 cases did so for oestrogen receptor. Variable positive staining for α-smooth muscle actin, S100 and glial fibrillary acidic protein (GFAP) was seen. NR4A3 and EWSR1 gene rearrangements were not detected in 13 and 11 examined cases, respectively. Clinical follow-up data for the 14 patients showed that 13 were alive without disease and one had been lost to follow-up; four patients developed local recurrence and/or metastases.

CONCLUSION

The designation 'myxoepithelioid tumour with choroid features' (METC) was proposed as a tumour with intermediate malignancy controllable with appropriate treatment, including the entity of myoepithelioma-like tumour of the vulvar region. METC represents a novel and independent subset that is histologically, biologically and clinically distinct from already existing SMARCB1/INI1-deficient soft-tissue tumours.

A deep learning model to detect pancreatic ductal adenocarcinoma on endoscopic ultrasound-guided fine-needle biopsy

Histopathological diagnosis of pancreatic ductal adenocarcinoma (PDAC) on endoscopic ultrasonography-guided fine-needle biopsy (EUS-FNB) specimens has become the mainstay of preoperative pathological diagnosis. However, on EUS-FNB specimens, accurate histopathological evaluation is difficult due to low specimen volume with isolated cancer cells and high contamination of blood, inflammatory and digestive tract cells. In this study, we performed annotations for training sets by expert pancreatic pathologists and trained a deep learning model to assess PDAC on EUS-FNB of the pancreas in histopathological whole-slide images. We obtained a high receiver operator curve area under the curve of 0.984, accuracy of 0.9417, sensitivity of 0.9302 and specificity of 0.9706. Our model was able to accurately detect difficult cases of isolated and low volume cancer cells. If adopted as a supportive system in routine diagnosis of pancreatic EUS-FNB specimens, our model has the potential to aid pathologists diagnose difficult cases.

Serum NT-proBNP levels and histopathological myocardial fibrosis in autopsied cases from a Japanese community: The Hisayama Study

BACKGROUND

natriuretic peptide is associated with myocardial fibrosis in animal models and among patients with heart disease. However, it remains unclear whether serum N-terminal pro-B-type peptide (NT-proBNP) levels are associated with histopathologically proven myocardial fibrosis among individuals without apparent heart disease. This study aimed to evaluate the association between serum NT-proBNP levels and the histopathologically estimated myocardial fibrotic area in autopsied samples from a community.

METHODS

we selected 63 cases without apparent heart disease with available data of serum NT-proBNP concentrations within six years before death (average age: 82 years; male: 52%) from autopsied cases in a community, and evaluated the percentage areas of myocardial fibrosis in four cardiac segments from each case (i.e. 252 cardiac segments in total). The association between serum NT-proBNP levels and the percentage area of myocardial fibrosis was estimated using a linear mixed model for repeated measures.

RESULTS

serum NT-proBNP levels were positively correlated with myocardial fibrotic area [Pearson's correlation coefficient: r = 0.49 (95% confidence interval: 0.28-0.66), p <0.001]. Serum NT-proBNP levels were significantly associated with the percentage areas of myocardial fibrosis after adjusting for potential confounding factors. There was no evidence of heterogeneity in the association between the subgroups with and without reduced estimated glomerular filtration rate (<60 mL/min/1.73 m²).

CONCLUSIONS

the present study demonstrated that elevated serum NT-proBNP levels were associated with the histopathologically measured myocardial fibrotic area in autopsied cases from a community. These findings may help clarify the association between elevated serum NT-proBNP levels and myocardial fibrosis and their influence on prognosis.

The association between the expression of PD-L1 and CMTM6 in undifferentiated pleomorphic sarcoma

BACKGROUND

Undifferentiated pleomorphic sarcoma (UPS) is a sarcoma with a poor prognosis. A clinical trial, SARC028, revealed that treatment with anti-PD-1 drugs was effective against UPS. Studies have reported that UPS expresses PD-L1, sometimes strongly (≥ 50%). However, the mechanism of PD-L1 expression in UPS has remained unclear. CKLF-like MARVEL transmembrane domain containing 6 (CMTM6) was identified as a novel regulator of PD-L1 expression. The positive relationship between PD-L1 and CMTM6 has been reported in several studies. The aim of this study was thus to examine CMTM6 expression in UPS and evaluate the relationship between PD-L1 and CMTM6 in this disease.

MATERIALS AND METHODS

Fifty-one primary UPS samples were subjected to CMTM6 and PD-L1 immunostaining. CMTM6 expression was assessed using proportion and intensity scores. CMTM6 gene copy number was also evaluated using a real-time PCR-based copy number assay. We also analyzed the mRNA expression and copy number variation of PD-L1 and CMTM6 in The Cancer Genome Atlas (TCGA) data.

RESULTS

TCGA data indicated that the mRNAs encoded by genes located around 3p22 were coexpressed with CMTM6 mRNA in UPS. Both proportion and intensity scores of CMTM6 positively correlated with strong PD-L1 expression (≥ 50%) (both p = 0.023). CMTM6 copy number gain increased CMTM6 expression. Patients with UPS with a high CMTM6 intensity score had a worse prognosis for overall survival.

CONCLUSIONS

UPS showed variation in CMTM6 copy number and CMTM6 expression. CMTM6 expression was significantly correlated with PD-L1 expression, especially with strong PD-L1 expression.

Morphological, immunohistochemical, and genomic analyses of papillary renal neoplasm with reverse polarity

Papillary renal neoplasm with reverse polarity (PRNRP) is a recently proposed entity of renal tumor. It shows a far better prognosis than papillary renal cell carcinoma (PRCC) and frequently has KRAS missense mutation. In this study, we compared 14 cases of PRNRP and 10 cases of PRCC type 1 (PRCC1) and type 2 (PRCC2) from clinical, morphological, immunohistochemical, and molecular biological perspectives. We subjected all PRNRP and PRCC cases to immunohistochemical analysis. Whole-exome sequencing using next-generation sequencing (NGS) was performed for six cases of PRNRP, three cases of PRCC1, and four cases of PRCC2. A search for KRAS gene mutation in the remaining eight cases of PRNRP was performed by polymerase chain reaction (PCR) sequencing. The results showed that all cases of PRNRP were pT1N0M0, none of which followed a course of recurrence or tumor-related death. Immunohistochemical analysis revealed diffuse staining of CK7, EMA, PAX8, and GATA3 but weak or negative staining of CD10, CD15, and AMACR in PRNRP. By NGS and PCR, KRAS missense mutation was detected in 11 of 14 PRNRP cases, although pathogenic KRAS mutation was not observed in PRCC1 and PRCC2. NGS analysis revealed less tumor mutation burden in PRNRP than in PRCC. PRNRP also showed no specific chromosomal copy number abnormalities, including gains of 7 and 17. In conclusion, we propose that PRNRP is a distinct condition from PRCC.

ARID1A Deficiency Is Associated With High Programmed Death Ligand 1 Expression in Hepatocellular Carcinoma

The clinicopathological features of carcinomas expressing AT-rich interaction domain 1a (ARID1A) and programmed death ligand 1 (PD-L1) in HCC are poorly understood. Here, we examined ARID1A and PD-L1 expression in surgically resected primary hepatocellular carcinoma (HCC) and the association of ARID1A and PD-L1 expression with clinicopathological features and patient outcomes. Their association with ARID1A expression and tumor-associated CD68-positive macrophage was further explored. Using a database of 255 patients who underwent hepatic resection for HCC, immunohistochemical staining of ARID1A, PD-L1, and CD68 was performed. We also analyzed the expression PD-L1 after ARID1A knockdown in HCC cell lines. Samples from 81 patients (31.7%) were negative for ARID1A. Negative ARID1A expression was significantly associated with male sex, high alpha-fetoprotein, high des-gamma-carboxyprothrombin, large tumor size, high rate of poor differentiation, microscopic intrahepatic metastasis, and PD-L1 expression. In addition, negative ARID1A expression was an independent predictor for recurrence-free survival, overall survival, and positive PD-L1 expression. Stratification based on ARID1A and PD-L1 expression in cancer cells was also significantly associated with unfavorable outcomes. PD-L1 protein expression levels were increased through phosphoinositide 3-kinase/AKT signaling after ARID1A knockdown in HCC cells. HCC with ARID1A-low expression was significantly correlated with high levels of tumor-associated CD68-positive macrophage. Conclusion: Our large cohort study showed that ARID1A expression in cancer cells was associated with a poor clinical outcome in patients with HCC, PD-L1 expression in cancer cells, and tumor microenvironment. Therefore, ARID1A may be a potential molecular biomarker for the selection of patients with HCC for anti-programmed death 1/PD-L1 antibody therapy.

Nectin Cell Adhesion Molecule 4 (NECTIN4) Expression in Cutaneous Squamous Cell Carcinoma: A New Therapeutic Target?

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer, and its incidence is rising because of the aging population. Nectin cell adhesion molecule 4 (NECTIN4) is involved in the progression of tumors and has attracted interest as a potential therapeutic target. However, little is known about the expression and significance of NECTIN4 in cSCC. The aim of this study was to determine the expression and function of NECTIN4 in cSCC. Immunohistological NECTIN4 expression was investigated in tissues from 34 cSCC patients. Using an A431 human SCC cell line, the role of NECTIN4 in the regulation of cell–cell attachment and migration and proliferation was assessed. NECTIN4 was expressed in most cSCC tissues and on the plasma membrane of A431 cells. Silencing of NECTIN4 prevented cell–cell attachment and induced the expression migration-related molecules, leading to an increase in cell migration. Knockdown of NECTIN4 downregulated extracellular signal-regulated kinase signaling, decreased cyclin D1 expression, and inhibited cell proliferation. These results show that NECTIN4 is expressed in cSCC and functions in the regulation of cell–cell interactions, as well as in the migration and proliferation of SCC cells. NECTIN4-targeted therapy may serve as a novel and promising treatment for cSCC.

Cytolytic activity score as a biomarker for antitumor immunity and clinical outcome in patients with gastric cancer

BACKGROUND

A simple measure of immune cytolytic activity (CYT) base on mRNA expression levels of two genes, GZMA and PRF1, was recently reported. Here, we aimed to evaluate the CYT score's potential as a measure of antitumor immunity and predictor of clinical outcome in gastric cancer (GC) patients.

MATERIALS AND METHODS

We evaluated the correlations between tumor-infiltrating immune cells and the CYT score in 238 GC samples from The Cancer Genome Atlas (TCGA). Next, we investigated CYT score associations with molecular subtypes, somatic mutation load, and immune checkpoint molecules in GC samples from TCGA and Asian Cancer Research Group (ACRG). Moreover, we evaluated the clinical significance of the CYT score calculated by reverse transcription (RT)-quantitative PCR (qPCR) data in 123 GC samples and the association of the CYT score with the response to anti-PD-1 therapy in 7 GC samples from Kyushu University Hospital.

RESULTS

The CYT score positively correlated with the proportions of tumor-infiltrating CD8+ T cells and macrophages and negatively correlated with the proportion of regulatory T cells in GC tissues. A high CYT score was associated with common immune checkpoint molecules, a high mutation, the Epstein-Barr virus subtype, and the microsatellite instability subtype in GC. Moreover, a low CYT score was a poor prognosis factor in patients with GC. Finally, the CYT score was higher in a responder to anti-PD-1 therapy compared to nonresponders.

CONCLUSION

The CYT score reflects antitumor immunity and predicts clinical outcome in GC patients.

Brachyury expression in intracranial SMARCB1-deficient tumors: important points for distinguishing poorly differentiated chordoma from atypical teratoid/rhabdoid tumor

Loss of SMARCB1 protein expression has recently been identified in a variety of tumor types such as poorly differentiated chordoma (PCh) and malignant rhabdoid tumor (MRT) including atypical teratoid/rhabdoid tumor (AT/RT). PCh is characterized by poorly differentiated epithelioid tumor cells, sheet arrangement, and coexpression of nonepithelial and epithelial markers. Rhabdoid cells are sometimes present. Therefore, the differentiation of these tumors is often difficult. Brachyury is a transcription factor within the T-box family typically expressed in notochord tissue and chordomas. Some studies have reported high specificity and sensitivity of brachyury expression in chordomas. In the present study, we analyzed immunohistochemical brachyury expression in SMARCB1-deficient tumors and discuss important clinicopathological and diagnostic points, especially in cases of intracranial SMARCB1-deficient tumors with brachyury expression. Brachyury and cytokeratin immunoexpression status was examined in 42 formalin-fixed paraffin-embedded SMARCB1-deficient tumor specimens (PCh, 6 cases; extra-central nervous system [CNS] MRT, 26 cases; AT/RT, 10 cases) and 25 cases of conventional chordoma (CCh). All cases of PCh and CCh showed diffuse immunopositivities for cytokeratin 8, pan-cytokeratin, and brachyury. Brachyury immunoexpression was present in 2 extra-CNS MRT (8%) and 5 AT/RT (50%) cases, but immunopositivity was focal not diffuse. Indeed, in almost all cases of AT/RT (cytokeratin 8, 7/10 cases; pan-cytokeratin, 7/10 cases) and extra-CNS MRT (cytokeratin 8, 23/26 cases; pan-cytokeratin, 25/26 cases), fewer than 50% of cells showed immunoreactivity. Although the histological and clinical features of PCh resemble those of AT/RT, semiquantitative evaluations of the degree of brachyury and cytokeratin immunoexpressivity may help to distinguish PCh from AT/RT.

En Bloc Resection for a Malignant Spine Tumor After Balloon Kyphoplasty: Histological Findings of a Retrieved Vertebral Body: A Case Report

CASE

A 45-year-old woman with severe back pain underwent percutaneous curettage and balloon kyphoplasty (BKP) of a lesion believed to be aneurysmal bone cyst. Three months after BKP, local recurrence was observed, and the histological diagnosis was revised to malignant tumor. Thus, we performed a total en bloc spondylectomy, and the L3 vertebral body was resected. She was reconstructed by titanium expandable cage, rod, and pedicle screws. We observed viable tumor cells and foreign body reaction adjacent to the polymethylmethacrylate cement, carrying no bone necrosis.

CONCLUSIONS

The long-term durability and safety of BKP for metastatic spine disease should be further clarified.

CMTM6 Stabilizes PD-L1 Expression and Is a New Prognostic Impact Factor in Hepatocellular Carcinoma

CKLF-like MARVEL transmembrane domain containing 6 (CMTM6) was identified as a regulator of programmed death ligand 1 (PD-L1), which induces antitumor immunity in several cancers. This study aimed to clarify the relationship between CMTM6 and PD-L1 expression and clinical outcomes in patients with hepatocellular carcinoma (HCC). In total, 259 patients with HCC who had undergone hepatic resection were enrolled. Immunohistochemical staining for CMTM6 and PD-L1 was performed. The relationships between CMTM6 expression and the clinicopathological characteristics and outcomes were analyzed. Additionally, the stabilization of PD-L1 expression and regulation of malignant activities by CMTM6 were examined in vitro. Our patients were divided into high (n = 65, 25.1%) and low (n = 194, 74.9%) CMTM6 expression groups. High CMTM6 expression was significantly associated with malignant aggregates, including poor differentiation (P < 0.0001), microscopic intrahepatic metastasis (P = 0.0369), and multiple intrahepatic recurrences (P = 0.0211). CMTM6 expression was significantly correlated with PD-L1 expression in HCC tissues (P < 0.0001). The patients were classified into three groups: high CMTM6/PD-L1 positive (n = 21), high CMTM6/ PD-L1 negative (n = 44), and low CMTM6 (n = 194) expression pattern groups. Overall survival was significantly different among the three groups (P < 0.0001). Additionally, immunohistochemical double staining revealed that CMTM6 and PD-L1 were co-expressed on HCC cells. In vitro, PD-L1 expression was enhanced at late time points in the presence of CMTM6 expression. CMTM6 also regulated epithelial-to-mesenchymal transition and stemness phenotypes in HCC cells. Conclusion: Our large cohort study found that CMTM6 co-expressed with PD-L1 was strongly associated with the clinical outcome in patients with HCC. The evaluation of CMTM6 combined with PD-L1 in HCC might be useful for patient selection in immune checkpoint therapy.

Three cases of synovial sarcoma of gastric wall: A case report and review of the literature

Synovial sarcoma (SS) is a malignant soft tissue neoplasm that occurs in various parts of the human body, but most commonly affects the extremities. Its diagnosis of synovial sarcoma often requires adjunctive techniques such as immunohistochemical staining and molecular studies, especially for synovial sarcoma at unusual locations. SS at a gastrointestinal location is exceedingly rare. We report here three cases of primary gastric synovial sarcoma. Malignant gastric mesenchymal tumor has many differential diagnoses other than synovial sarcoma, such as gastrointestinal stromal tumor (GIST), leiomyosarcoma, schwannoma, malignant peripheral nerve sheath tumor (MPNST) and so on. In our three cases, using reverse transcription polymerase chain reaction (RT-PCR) and direct sequencing, we detected an SS18-SSX1 fusion gene, which is specific to synovial sarcoma. In addition, we found the reduced expression of SMARCB1/INI1 in the tumor cells in two of the three cases. Through histopathological, immunohistochemical, and molecular analyses, we confirmed the diagnosis of primary gastric synovial sarcoma.

GLI2 but not GLI1/GLI3 plays a central role in the induction of malignant phenotype of gallbladder cancer

We previously reported that Hedgehog (Hh) signal was enhanced in gallbladder cancer (GBC) and was involved in the induction of malignant phenotype of GBC. In recent years, therapeutics that target Hh signaling have focused on molecules downstream of smoothened (SMO). The three transcription factors in the Hh signal pathway, glioma‑associated oncogene homolog 1 (GLI1), GLI2, and GLI3, function downstream of SMO, but their biological role in GBC remains unclear. In the present study, the biological significance of GLI1, GLI2, and GLI3 were analyzed with the aim of developing novel treatments for GBC. It was revealed that GLI2, but not GLI1 or GLI3, was involved in the cell cycle‑mediated proliferative capacity in GBC and that GLI2, but not GLI1 or GLI3, was involved in the enhanced invasive capacity through epithelial‑mesenchymal transition. Further analyses revealed that GLI2 may function in mediating gemcitabine sensitivity and that GLI2 was involved in the promotion of fibrosis in a mouse xenograft model. Immunohistochemical staining of 66 surgically resected GBC tissues revealed that GLI2‑high expression patients had fewer numbers of CD3+ and CD8+ tumor‑infiltrating lymphocytes (TILs) and increased programmed cell death ligand 1 (PD‑L1) expression in cancer cells. These results suggest that GLI2, but not GLI1 or GLI3, is involved in proliferation, invasion, fibrosis, PD‑L1 expression, and TILs in GBC and could be a novel therapeutic target. The results of this study provide a significant contribution to the development of a new treatment for refractory GBC, which has few therapeutic options.