Effects of laser pulse duration on the formation dynamics of laser-induced periodic nanostructures.

Formation dynamics of laser-induced periodic surface structures (LIPSSs) on the SiC substrates were described with varying pulse numbers and pulse duration. As the number of laser pulses increases, two significant transformations become evident in the progression of structural formations. First from surface roughening with nanoparticles to LIPSS with the period that is slightly shorter than the laser wavelength. Second it turns to LIPSS with a period less than half the laser wavelength. It is found that maintaining the crystallinity is the key to changing the structures. In the cases of longer pulse width than sub-nanoseconds, no LIPSS formations are observed or LSFL does not change to HSFL because the irradiated area is poly-crystallized.

Apocrine carcinoma with marked sebocyte-like cytological features: A report of two cases.

Apocrine carcinoma cases with sebaceous differentiation have not been reported and can be misdiagnosed as sebaceous carcinoma. We present two cases of apocrine carcinoma with marked sebocyte-like cytological features. Tumors were observed in the left axilla of a 68-year-old man (Case 1) and the right axilla of a 72-year-old man (Case 2). Both patients presented with multiple lymph node metastases. Histopathology revealed densely distributed solid nests of tumor cells containing foamy cytoplasm and enlarged round nuclei with prominent nucleoli. The tumor cells diffusely expressed adipophilin, PRAME (cytoplasmic pattern), androgen receptor, BerEP4, and GCDFP15 but did not express p63 in both cases. PIK3CA E726K and H1047R mutations were detected in Cases 1 and 2, respectively. Tumor location in the axilla, the presence of eosinophilic granular cytoplasm, prominent nucleoli, and PIK3CA mutations, immunoreactivity for BerEP4 and GCDFP15, and lack of p63 immunoexpression findings matched apocrine carcinoma characteristics, but not sebaceous carcinoma. Thus, apocrine carcinoma can demonstrate intracytoplasmic lipid accumulation and rarely exhibit sebocyte-like cytological features. Apocrine carcinoma should be distinguished from sebaceous carcinoma due to the former's higher metastatic potential and lack of association with Muir-Torre syndrome.

Loss of p16 Immunoexpression and Deletions of CDKN2A in the Progression of Extramammary Paget Disease: An Immunohistochemical and Genetic Study of 24 Invasive/Metastatic Cases.

ABSTRACT: Information regarding the genetic alterations in extramammary Paget disease (EMPD) is scarce. This study investigated the significance of CDKN2A and MTAP alterations in EMPD progression using immunohistochemistry and panel DNA sequencing. In total, 24 invasive/metastatic EMPD cases were included in this study. The immunoexpression of p16 and MTAP in the primary in situ, primary invasive, and metastatic tumor components was evaluated. Panel DNA sequencing was performed for metastatic tumor components in 5 of the 24 cases. Immunoexpression of p16 in the in situ tumor component was at least partially preserved in all 19 tested cases (100%). By contrast, the invasive tumor component was diffusely or partially lost in 18 (81.8%) of 22 tested cases. Regarding the foci of lymph node metastasis, 13 (81.2%) of the 16 patients showed a significant loss of p16 expression. Loss of MTAP immunoexpression was observed less frequently compared with the loss of p16 expression. CDKN2A homozygous deletions were confirmed in all 5 tested cases by sequencing, whereas MTAP deletions were detected in only 2 cases. In conclusion, p16 expression loss and CDKN2A deletions can be frequently seen in invasive/metastatic cases of EMPD.

A Japanese case of familial malignant melanoma with germline CDK4 variant incidentally diagnosed by cancer genome profiling.

Familial malignant melanoma (FMM) is a hereditary tumor that is quite rare in Japan; to date, the germline CDK4 variant has scarcely been reported around the world. Thus, we report on a woman with FMM who developed salivary gland cancer, for which a germline pathogenic variant of CDK4 was incidentally identified through comprehensive genomic profiling. She had a history of multiple atypical nevi and a facial melanoma since her 30 s and multiple family histories of melanoma; however, none of her relatives were aware of its heredity. Genetic counseling and skin surveillance were performed. Precision medicine for cancer can discover this rare genetic syndrome and provides us with the opportunity to manage the health of patients and their relatives.

Clinicopathologic and genetic characterization of invasive melanoma with BRAF V600K mutation: A study of 16 cases.

BACKGROUND: The clinicopathologic and genetic features of cutaneous melanoma with a BRAF V600K mutation are not well-known. We aimed to evaluate these characteristics in comparison with those associated with BRAF V600E. METHODS: Real-time polymerase chain reaction (PCR) and/or the MassARRAY® system were used to detect BRAF V600K in 16 invasive melanomas and confirm BRAF V600E in another 60 cases. Immunohistochemistry and panel next-generation sequencing were used to evaluate protein expression and tumor mutation burden, respectively. RESULTS: The median age of melanoma patients harboring the BRAF V600K mutation (72.5 years) was higher than those with the BRAF V600E (58.5 years). The two groups also differed in sex (13/16 [81.3%] male in the V600K group vs. 23/60 [38.3%] in V600E) and in the frequency of scalp involvement (8/16 [50.0%] in V600K vs. 1/60 [1.6%] in V600E). The clinical appearance was similar to a superficial spreading melanoma. Histopathologically, non-nested lentiginous intraepidermal spread and subtle solar elastosis were observed. One patient (1/13, 7.7%) had a pre-existing intradermal nevus. Diffuse PRAME immunoexpression was seen in only one (14.3%) of seven tested cases. Loss of p16 expression was observed in all 12 cases (100%) analyzed. The tumor mutation burden was 8 and 6 mutations/Mb in the two tested cases. CONCLUSIONS: Melanoma carrying the BRAF V600K mutation showed the predominance on the scalp of elderly men, lentiginous intraepidermal growth, subtle solar elastosis, possible existence of intradermal nevus component, frequent loss of p16 immunoexpression, limited immunoreactivity for PRAME, and intermediate tumor mutation burden.

Co-existence of BRAF V600E-mutated malignant melanoma and BRAF V600E-mutated Langerhans cell histiocytosis: A case report.

Langerhans cell histiocytosis (LCH) is a neoplastic condition of Langerhans cells, and can be associated with other neoplasms, especially BRAF-mutant hematological tumors and papillary thyroid carcinoma. Here we present the first case of co-existing LCH and low cumulative sun damage (low-CSD) melanoma, both of which had a BRAF V600E mutation. A 49-year-old man had a 45 × 43 × 15 mm semi-pedunculated, pigmented tumor in his back but had no other systemic symptoms. Histopathology revealed a 2-mm-sized incidental focus of LCH within a large lesion of low-CSD melanoma. Diffuse immunoexpression of CD1a, langerin/CD207, S100 protein, and BRAF (VE1) was observed in the focus of LCH. Sanger sequencing with microdissection confirmed BRAF V600E mutation in the component of LCH. Interestingly, the advanced melanoma also harbored the same BRAF V600E mutation, although the significance of this tumor combination is still unknown.

Topical corticosteroid therapy for facial acneiform eruption due to EGFR inhibitors in metastatic colorectal cancer patients: a randomized controlled trial comparing starting with a very strong or a weak topical corticosteroid (FAEISS study, NCCH1512, colorectal part).

BACKGROUND: Although pre-emptive therapy with oral tetracycline, moisturizer, sunscreen, and topical corticosteroid is useful for preventing acneiform eruption (AfE) due to epidermal growth factor receptor (EGFR) inhibitors, no studies have examined the efficacy of topical corticosteroids themselves, or investigated the optimal potency of corticosteroid for treating facial AfE (FAfE). PATIENTS AND METHODS: Screened patients with RAS wild-type colorectal cancer started pre-emptive therapy with oral minocycline and moisturizer on initiation of cetuximab or panitumumab therapy. Patients who developed grade 1 or 2 FAfE were randomly allocated to two groups: a ranking-down (RD) group that started with a very strong corticosteroid and serially ranked down every 2 weeks unless FAfE exacerbated; and a ranking-up (RU) group that started with a weak corticosteroid and serially ranked up at exacerbation. FAfE grade, patient quality of life, and adverse events (AEs) with topical corticosteroid were evaluated every 2 weeks. The primary endpoint was the total number of times grade 2 or higher FAfE was identified in the central review of the 8-week treatment period. RESULTS: No significant differences in total numbers of grade 2 or higher FAfE or in AEs caused by topical corticosteroids were observed between groups during the 8 weeks. Incidence of grade 2 or higher FAfE tended to be lower in the RD group during the first 2 weeks. CONCLUSION: Considering the long-term care of FAfE, the RU regimen appears suitable and should be considered the standard treatment for FAfE due to EGFR inhibitor therapy. TRIAL REGISTRATION: UMIN Clinical Trials Registry (UMIN000024113).

Sweat Gland Carcinoma With Neuroendocrine Differentiation of the Areola as a Potential Clinicopathologic Mimicker of Male Breast Carcinoma and Syringocystadenocarcinoma Papilliferum.

ABSTRACT: Sweat gland carcinoma with neuroendocrine differentiation (SCAND) is a newly proposed tumor entity of primary cutaneous apocrine/eccrine adnexal tumor with neuroendocrine differentiation. The histopathologic variations are not yet well known. In this article, we present a case of SCAND mimicking male breast cancer and syringocystadenocarcinoma papilliferum. A 68-year-old man presented with a reddish 12-mm nodule on his left areola. No lymph node or distant metastases were observed. The patient was disease free 1 year and 9 months after the tumor was surgically resected but died of cerebral hemorrhage. Histopathological examination revealed a predominantly intradermal tumor with marked syringotropism, mimicking a component of mammary ductal carcinoma in situ. In addition, another tissue section displayed a cup-shaped papillated tumor with syringocystadenocarcinoma papilliferum-like features, which were also seen because of marked syringotropism. Diffuse immunoexpression of cytokeratin 7, cytokeratin 19, chromogranin A, synaptophysin, INSM1, estrogen receptor, carcinoembryonic antigen, epithelial membrane antigen, and GATA3 was observed in the tumor, but no BRAF immunoexpression was seen. The present case would help us to understand the histopathological variation and differential diagnosis of SCAND. The histopathological diagnosis of male breast cancer or syringocystadenocarcinoma papilliferum should be made by ruling out SCAND.

Large Cell Neuroendocrine Carcinoma of the Skin/Conjunctiva: A Series of 6 Cases including 1 Combined Case With Squamous Cell Carcinoma.

ABSTRACT: This study sought to reveal the clinicopathologic characteristics of large cell neuroendocrine carcinoma (LCNEC) of the skin/conjunctiva. The retrieved patients included 3 men and 3 women with a median age of 85 (63-95) years. All lesions occurred on the face, including the ears, with a median tumor size of 11.5 (7-65) mm. Lymph node metastasis was observed in 5 (83%) of 6 cases, and distant metastasis was noted in 2 (33%). One patient (17%) who had a 13-mm-sized tumor died of the tumor 13 months after excision. All tumors were mainly located in the dermis, and one of them also exhibited intraepithelial spreading. The cytology resembled that of an LCNEC in other organs. No adnexal differentiation was observed. Five cases were of the pure type, but one had a component of squamous cell carcinoma. Immunoreactivities for CAM5.2, CK7, CK19, BerEP4, epithelial membrane antigen, neuron-specific enolase, synaptophysin, c-KIT, GATA3, and bcl-2 were frequently present, but CK20, neurofilament, Merkel cell polyomavirus large T antigen, mammaglobin, estrogen receptor, HER2, and TTF1 were completely negative in all cases. Mutant-pattern immunostaining of p53, PTEN, and Rb was frequently observed. The Ki67 rate exceeded 70% in all cases. LCNEC of the skin/conjunctiva is a morphologically-defined group of primary cutaneous/conjunctival neuroendocrine neoplasm, although it may be heterogeneous similar to other-site LCNEC or Merkel cell carcinoma. This study highlighted the predominant location for the face, high metastatic and lethal potential, possible combination with other tumor components, and frequent mutant-type immunoexpressions of p53, PTEN, and Rb in this tumor group.

Characteristic Clinicopathological Features of Secondary Extramammary Paget Disease With Underlying Anorectal Adenocarcinoma: Evenly Circumferential Perianal Distribution, Fibroepithelioma of Pinkus-like Changes, and Subepidermal Mucin Deposits Without Invasive Tumor Cells.

ABSTRACT: This study aimed to identify the clinical and histopathological characteristics of secondary extramammary Paget disease (EMPD) with underlying anorectal adenocarcinoma so as to differentiate it from primary cutaneous EMPD. Seventeen and 8 cases of primary and secondary EMPD with anorectal adenocarcinoma, respectively, were retrieved from the pathology archive and the clinical and histopathological features reviewed. The tumor samples from 21 cases were totally resected specimens, whereas 3 and 1 of secondary and primary cases were punch biopsied, respectively. All 8 (100%) cases of secondary EMPD presented evenly distributed perianal lesions. By contrast, 4 of 17 (23.5%) primary EMPD cases had perianal skin lesions and displayed an uneven, asymmetrical distribution around the anus. Fibroepithelioma of Pinkus-like changes and subepidermal mucin deposits with no or few invasive tumor cells were observed in 6 (75%) and 3 (37.5%) of the 8 secondary EMPD cases, respectively, although 3 secondary case samples were small biopsy specimens. Both the histopathological changes were not observed in any of the 17 primary EMPD cases. Evenly circumferential perianal distribution, fibroepithelioma of Pinkus-like changes, and subepidermal mucin deposits without invasive tumor cells were characteristic to cases of secondary EMPD with anorectal adenocarcinoma. These clinicopathological features could be used to differentiate between secondary and primary EMPD.

Large Plaque-type Blue Nevus with GNAQ Q209P Mutation, Involving Mammary Gland Tissue: Under-Recognized Mammary Condition as an Origin of Primary Mammary Melanocytic Tumors.

ABSTRACT: Plaque-type blue nevus is a rare variant of blue nevi that was first described in 1954. This article presents clinical, macroscopic, histopathological, and genetic findings for a case of large plaque-type blue nevus expanding into the mammary gland tissue as well as the skin of the right breast. A 63-year-old woman presented with a congenital, large, blue-colored macule limited to the hypochondriac area of the right breast. A nodule 8 mm in diameter was also present in the mammary gland tissue. Magnetic resonance imaging was unable to detect diffuse melanin deposition in the mammary gland tissue, but pigmentation in the whole mammary parenchyma was observed in the cut surfaces of the mastectomy specimen. Histopathology revealed a sparse distribution of dendritic melanocytes in whole sections of the mammary fibrous tissue and partial sections of the dermis. The histopathological criteria for atypical cellular blue nevus were fulfilled for the mammary tumor. Nodal blue nevus was diagnosed in the sentinel lymph node. Sanger sequencing confirmed the GNAQ Q209P mutation, which was also identified in all 4 literature cases of plaque-type blue nevus, but rarely in conventional blue nevi and uveal melanoma. It should be noted that plaque-type blue nevus can expand into the mammary gland tissue, even if the pigmented lesion does not exist on the overlying breast skin. The mammary condition can be the origin of primary mammary melanocytic tumors. Mosaicism of the GNAQ Q209P mutation can be a characteristic genetic alteration to extensive blue nevi, including plaque-type blue nevus.

Adherence to a topical moisturizing preparation for regorafenib-related hand-foot skin reaction.

OBJECTIVE: Application of topical moisturizing preparations is important for the prevention and palliation of hand-foot skin reaction induced by multi-kinase inhibitor. Application adherence of topical moisturizing preparations in clinical practice has rarely been reported. This study investigated the factors affecting adherence to the application of topical moisturizing preparations in patients administered regorafenib. METHODS: The subjects were patients administered regorafenib (n = 118). Consumption of a urea-based moisturizing ointment, hand-foot skin reaction grade (CTC-AE ver 3.0), treatment duration, and dose of regorafenib, factors that might affect the onset of symptoms and adherence, including age, sex, presence of a key person, working status, performance status, past use of capecitabine or epidermal growth factor receptor antibodies, and relative dose intensity were retrospectively investigated. The adherence to the topical moisturizing ointment (<21 g per week) was judged as poor. The data were analyzed by logistic regression analysis. RESULTS: Working status was associated with poor adherence, showing a positive correlation (odds ratio; 3.024, p = 0.023). In contrast, symptom grade of hand-foot skin reaction and regorafenib relative dose intensity showed negative correlation with poor adherence (odds ratio; 0.971, p = 0.012, and 0.485, p < 0.001, respectively). CONCLUSIONS: The results suggest that adherence decreases in patients with working. The relative dose intensity of regorafenib decreased when adherence to topical moisturizing ointments decreased. Severe hand-foot skin reaction could be associated with adherence. Patients consciously might not apply the ointment when hand-foot skin reaction did not become severe. It will be problematic for medical personnel to motivate patients for improving adherence to the use of moisturizing ointments.

A phase I and pharmacokinetic study of taladegib, a Smoothened inhibitor, in Japanese patients with advanced solid tumors.

Background This phase I dose-escalation study investigated the safety of the Smoothened inhibitor taladegib in Japanese patients with advanced solid tumors. Methods Patients received taladegib orally once daily for 28-day cycles, using a 3 + 3 dose-escalation method. The primary objective was the safety and tolerability of taladegib at doses up to the global recommended dose (400 mg). Secondary objectives included pharmacokinetics, changes in skin glioma-associated oncogene homolog 1 (Gli1) transcript levels, and antitumor activity. Results Nineteen patients received treatment (100 mg: 3; 200 mg: 3; 400 mg: 13). No dose-limiting toxicities (DLTs) were observed at doses of 100 mg or 200 mg; 3 of the 9 patients evaluable for DLTs at the 400 mg dose level experienced DLTs (thrombocytopenia: 1; decreased appetite: 2). The most commonly reported treatment-related adverse events were dysgeusia (13/19, 68.4%), decreased appetite (12/19, 63.2%), nausea (9/19, 47.4%), fatigue (9/19, 47.4%), and vomiting (6/19, 31.6%). The pharmacokinetic profile suggested that exposure to taladegib was higher in Japanese than non-Japanese patients, possibly related to differences in body weight and/or drug formulation. At all dose levels, a high level of inhibition of skin Gli1 transcript levels was observed after 15 and 30 days of exposure to taladegib. Partial response was achieved by 1 patient (basal cell carcinoma of the skin) and stable disease by 4 patients. Conclusions Taladegib doses of 100 mg and 200 mg, but not the global recommended dose of 400 mg, were well tolerated in this population of Japanese patients with advanced solid tumors.

Safety, tolerability, and pharmacokinetic profile of dabrafenib in Japanese patients with BRAF V600 mutation-positive solid tumors: a phase 1 study.

Background Dabrafenib is a BRAF inhibitor that has demonstrated clinical activity with a good tolerability profile in patients with BRAF V600E mutated metastatic melanoma. This study evaluated the safety and tolerability, pharmacokinetics and preliminary efficacy of dabrafenib in Japanese patients. Methods This phase I, open-label, dose escalation study was conducted in 12 Japanese patients with BRAF V600 mutation positive solid tumours. Primary endpoint was safety, assessed by monitoring and recording of all adverse events (AEs), serious AEs, drug-related AEs; secondary endpoints were pharmacokinetic profiles and efficacy measured by tumour response. This study is registered with ClinicalTrials.gov, number NCT01582997. Results Of the 12 patients enrolled, 3 each received 75 mg and 100 mg dabrafenib while 6 received 150 mg dabrafenib twice daily orally. Melanoma and thyroid cancer were the primary tumours reported in 11 (92%) and 1 (8%) patients respectively. Most AEs were grade 1 or 2 and considered related to study treatment. Most common AEs reported in the 12 patients were alopecia in 7 (58%); pyrexia, arthralgia and leukopenia in 6 (50%) each, hyperkeratosis and nausea in 4 (33%) each. Partial response as best overall response was reported in 7 of 12 (58%) patients and in 6 (55%) with malignant melanoma. No dose-limiting toxicity (DLTs) were reported during the DLT evaluation periods. Conclusions Dabrafenib was well tolerated and rapidly absorbed administered as single- or multiple dose. Comparable safety and pharmacokinetic profiles were observed compared with non-Japanese patients. Dabrafenib has promising clinical activity in Japanese patients with BRAF mutated malignant melanoma.

Randomized phase III trial of adjuvant therapy with locoregional interferon beta versus surgery alone in stage II/III cutaneous melanoma: Japan Clinical Oncology Group Study (JCOG1309, J-FERON).

The Dermatologic Oncology Group of Japan Clinical Oncology Group has started a randomized phase III trial to confirm the superiority of adjuvant therapy with locoregional interferon beta in overall survival over surgery alone for patients with pathological stage II/III cutaneous melanoma (JCOG1309). Patients in the interferon beta arm receive intra- or subcutaneous injections of interferon beta directly into the surgical site at a flat dose of 3 million units once per day. Treatment is repeated for 10 consecutive days every 8 weeks for a total of 3 courses during the induction phase, then 1-day injection every 4 weeks for 2.5 years. A total of 240 patients will be accrued from 17 Japanese institutions within 6.5 years. Primary endpoint is overall survival. Secondary endpoints are relapse-free survival, distant metastasis-free survival, pattern of recurrence, and adverse events. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000017494 [http://www.umin.ac.jp/ctr/index.htm].

Treatment strategy for cutaneous apocrine carcinoma.

BACKGROUND: Cutaneous apocrine carcinoma (CAC) is a rare adnexal carcinoma with only scattered reports about long-term follow-up. The aim of this study is to demonstrate clinical findings in the prognosis of CAC and discuss the treatment procedure. METHODS: The subjects were nine patients with a histological diagnosis of CAC who underwent wide excision and regional lymph node dissection as the initial treatment at Shizuoka Cancer Center Hospital. We examined the gender, age, site of involvement, additional treatment to prevent recurrence/metastasis, additional treatment after metastasis, and the follow-up data of the study patients. Then, we calculated the recurrence and 5-year (overall/recurrence-free) survival rates. RESULTS: The men-to-women ratio was 8:1. The patients ranged in age from 47 to 81 years (median, 67 years). The primary lesion was in the axilla in five patients and in the vulva in the other four patients. The follow-up period ranged from 9 to 204 months (median, 44 months). The recurrence-free 5-year survival rate was 63 %, and the overall 5-year survival rate was 75 %. CONCLUSIONS: We recommend wide local excision for a primary lesion and prophylactic regional lymph node dissection at initial therapy because of the high frequency of regional metastasis of CAC. Although CAC responds poorly to chemotherapy and radiotherapy, adjuvant radiotherapy may be used in advanced local or regional disease.

Accuracy of real-time ultrasound elastography in the differential diagnosis of lymph nodes in cutaneous malignant melanoma (CMM): a pilot study.

BACKGROUND: We investigated the diagnostic ability of real-time elastography to differentiate between reactive and metastatic lymph nodes in cutaneous malignant melanoma (CMM) patients and to determine the optimum cutoff value for elastography scores for diagnosis CMM. METHODS: Twenty lymph nodes (metastatic, n = 13; reactive, n = 7) from 12 patients with CMM were examined by both elastography and B-mode ultrasound in this prospective study. Elastographic patterns were given scores of 1-5 according to the percentage of high elasticity (hard) areas in the lymph node. Elastographic patterns 1, 2, 3, 4, and 5 were assigned elastography scores (ES) of 1, 2, 3, 4, and 5, respectively. B-mode ultrasound diagnosis was performed on the basis of the morphological patterns (balloon-shaped lymph node and loss of central echoes). The sensitivity, specificity, and accuracy were calculated, and receiver operating characteristic analysis was performed, comparing with elastograms and B-mode images, with histological findings as the reference standard. RESULTS: Sensitivity, specificity, and accuracy of elastography were 100, 71, and 90 %, respectively, with an ES cutoff value of 3; 92, 100, and 95 % for elastography with an ES cutoff value of 4; and 77, 57, and 70 % for B-mode ultrasound. CONCLUSION: Elastography can enhance the diagnostic accuracy of ultrasound for differentiating between reactive and malignant lymph nodes in CMM and might eliminate the need for sentinel lymph node biopsy. The optimum ES cutoff value for reactive versus metastatic lymph nodes is 4.

Impact of Mutations in Subunit Genes of the Mammalian SWI/SNF Complex on Immunological Tumor Microenvironment.

BACKGROUND/AIM: Recently, inactivating somatic mutations of SWI/SNF chromatin-remodeling genes in cancers have been reported. However, few studies have been performed regarding the immunological analysis of the tumor microenvironment (TME) in chromatin remodeling complex gene-mutated tumors. In the present study, we identified cancer patients harboring various mammalian SWI/SNF complex mutations and investigated the immunological features in those mutated cancers. PATIENTS AND METHODS: Cancer patients harboring any type of chromatin remodeling complex gene mutation were selected and clinicopathological features were compared between chromatin remodeling complex gene expression-low and expression-high groups. Specifically, expression levels of immune response-associated genes and cancer-associated genes were compared between the SMARCA4 expression-low and expression-high groups using volcano plot analysis. RESULTS: Among cancers harboring PBRM1, SAMRACA4 and ARID2 gene mutations, T-cell marker and mature B-cell marker genes were up-regulated in the tumor. Specifically, T-cell effector genes (CD8B, CD40LG), central memory marker genes (CD27, CCR7) and mature B-cell marker genes (CD20, CD38, CD79 and IRF4) were up-regulated, and cancer-associated genes including MYB, MYC and AURKB genes were down-regulated in the SMARCA4 expression-low group. Remarkably, heatmap of gene expression and immunohistochemistry (IHC) data demonstrated that the tertiary lymphoid structure (TLS) gene signature of mature B cells was up-regulated in SMACA4 gene-mutated stomach cancers. CONCLUSION: These results suggest that immune tumor microenvironment status, such as mature B cell recruitment featuring the TLS gene signature and immune activation mediated by cancer signal down-regulation, might contribute to the classification of SMARCA4 gene-mutated tumors as immune checkpoint blockade therapy-sensitive target tumors.