A case of hyalinizing trabecular tumor of the thyroid: diagnostic significance of PAX8-GLIS3 fusion.

BACKGROUND: Hyalinizing trabecular tumor (HTT) is an uncommon follicular cell-derived thyroid tumor classified as a low-risk neoplasm by the World Health Organization Classification of Tumors of Endocrine Organs, 5th edition. The PAX8-GLIS3 gene fusion is reportedly a pathognomonic genetic alteration of HTT. CASE PRESENTATION: A 43-year-old Japanese female was incidentally discovered to have an 8-mm, well-defined, hypoechoic mass in the left lobe of the thyroid gland by ultrasound examination. Contrast-enhanced computed tomography scan revealed a solid mass exhibiting slight homogeneous enhancement in the lower pole of the thyroid gland. The mass was diagnosed as atypia of undetermined significance by fine-needle aspiration cytology. The patient underwent left hemithyroidectomy with routine central compartment dissection. Histologic findings revealed tumor cells with elongated nuclei and intranuclear pseudoinclusions arranged with trabeculae architecture or small nests in hyalinized stroma. Weak membranous and cytoplasmic staining was found by MIB1 (Ki-67) immunostaining. The final diagnosis was HTT of the thyroid gland. Next-generation sequencing genetic analysis of a surgical specimen revealed no pathologic mutations, including BRAF, H/K/NRAS, or RET-PTC fusions. The PAX8-GLIS3 fusion was detected by RT-PCR. CONCLUSIONS: A rare case of HTT was demonstrated through imaging, cytologic, histologic and molecular investigations. PAX8-GLIS3 fusion detected by RT-PCR and Sanger sequencing was confirmed to be a genetic hallmark of HTT.

Prognostic impact of tumor-associated neutrophils in breast cancer.

OBJECTIVES: Neutrophils are the most common type of leukocyte in mammals and play an essential role in the innate immune system and anti-cancer responses. However, recent studies identified the presence of tumor-associated neutrophils (TANs) as a poor prognostic factor. The present study investigated whether relationships exist between TANs and the clinicopathological factors and genetic status of breast cancer. METHODS: A total of 196 breast cancer patients with sufficient biopsy, breast-conserving surgery, or mastectomy specimens between 2014 and 2021 in Hokuto Hospital were included. RESULTS: TANs were individually counted in the tumor stroma (TS) and tumor nest (TN). A higher density of TANs in both TS and TN correlated with tumor size (TS P = 0.010; TN P = 0.001), a high histological grade (TS P < 0.001; TN P < 0.001), the histological type (TS P = 0.009; TN P = 0.034), a high ratio of lymph node metastasis (TS P < 0.001; TN P < 0.001), an advanced stage of cancer (TS P < 0.001; TN P = 0.002), intrinsic subtypes (TS P < 0.001; TN P < 0.001), ERBB2 (TS P < 0.001; TN P < 0.001), MAP3K1 (TS P = 0.002; TN P = 0.023), and TP53 (TS P < 0.001; TN P < 0.001). A higher density of TANs in TS and TN also correlated with shorter disease-free survival and overall survival (P < 0.001). CONCLUSION: The present results suggest that a higher density of TANs correlates with unfavorable prognostic factors in breast cancer. Further research on clinicopathological and genetic factors associated with TANs in breast cancer is needed.

Impact of Tumor Grade Distribution on Genetic Alterations in Clear Cell Renal Cell Carcinoma and Prostate Cancer.

BACKGROUND/AIM: A genomic analysis based on next-generation sequencing is important for deciding cancer treatment strategies. Cancer tissue sometimes displays intratumor heterogeneity and a pathologic specimen may contain more than two tumor grades. Although tumor grades are very important for the cancer prognosis, the impact of higher tumor grade distribution in a specimen used for a genomic analysis is unknown. PATIENTS AND METHODS: We retrospectively analyzed the data of 61 clear cell carcinoma and 46 prostate cancer patients that were diagnosed between December 2018 and August 2022 using the GeneRead Human Comprehensive Cancer Panel or SureSelect PrePool custom Tier2. Genome annotation and curation were performed using the GenomeJack software. RESULTS: Tumor mutation burden (TMB) was increased in proportion to the higher tumor grade distribution in grade 2 clear cell renal cell carcinoma (ccRCC). In PC, Grade Group 3/4 specimens that included an increased distribution of Gleason pattern 4 had more frequent gene mutations. CONCLUSION: Our results suggest the importance of selecting the maximum distribution of higher tumor grade areas to obtain results on the precise gene alterations for genomics-focused treatments.

Salivary Duct Carcinoma Arising in the Submandibular Gland in a Patient with Neurofibromatosis Type 1.

A 71-year-old man with neurofibromatosis type 1 (NF1) presented to our department with a 1-week history of a painful mass in the left submandibular area. Computed tomography (CT) and magnetic resonance imaging revealed an irregular-shaped tumor with a diameter of 2.0 cm in the left submandibular gland and a metastatic lymph node with a diameter of 1.0 cm adjacent to the tumor. Fluorodeoxyglucose-positron emission tomography/CT revealed increased uptake in the tumor. Fine-needle aspiration cytology revealed atypical cells, suggesting salivary duct carcinoma (SDC). Left neck dissection with resection of the tumor and submandibular gland was performed under general anesthesia. Histologic examination revealed ductal formation with a solid, cystic, cribriform, and papillary structure with intraductal comedonecrosis, diagnosing as SDC originating in the submandibular gland (pT3N1M0 pStage III). Mutational analysis of 160 cancer-related genes by next-generation sequencing (NGS) revealed a germline and frameshift mutation in the NF1 gene (p.R2408Kfs*14) and a somatic and frameshift mutation in the TP53 gene (p.C176Wfs*22). The patient received postoperative radiotherapy to the left neck area at 66 Gy. No evidence of recurrence or metastasis has been observed as of 10 months postoperatively. This is the first reported case of SDC in the submandibular gland in a patient with NF1. The mutational data by NGS may contribute to a better understanding of the oncogenesis of SDC in patients with NF1.

Germline BRCA2 variant with low variant allele frequency detected in tumor-only comprehensive genomic profiling.

Germline BRCA1/2 variants in comprehensive genomic profiling (CGP) often exhibit variant allele frequency (VAF) exceeding 50%. However, when genomic loss occurs at the ipsilateral allele, including the germline variant in tumor cells, the VAF is low. This case report presents a patient with uterine sarcoma with a pathogenic BRCA2 mutation and low VAF in tumor-only CGP, which was later identified as a germline variant. When genomic alterations in BRCA1/2 are identified in tumor-only CGP, the possible germline origin of the variants should be considered, even if their VAF is very low.

BRAF V600E mutation co-existing with oncogenic mutations is associated with aggressive clinicopathologic features and poor prognosis in papillary thyroid carcinoma.

BACKGROUND: The aim of this study was to evaluate the correlation among mutations in cancer-related genes, clinicopathologic features, and clinical outcome in classical papillary thyroid carcinoma (PTC). PATIENTS AND METHODS: A total of 130 patients with classical PTC who underwent curative surgery between April 2012 and June 2023 at Hokuto Hospital were included. Mutations in targeted regions of 160 cancer-related genes were detected by next-generation sequencing (NGS)-based cancer panel testing. RESULTS: The BRAF V600E mutation was detected in 108 (83.1%) of 130 PTC patients. Among the 108 patients with the BRAF V600E mutation, other co-existing oncogenic mutations were found in 12 (9.2%) patients. When we divided into 3 groups of no mutations, BRAF V600E mutation alone, and BRAF V600E and other oncogenic mutations, significant differences were observed in terms of tracheal invasion (P = 0.0024), and bilateral neck lymph node metastasis (P = 0.0047). Kaplan-Meier analysis of overall survival (OS) revealed patients with BRAF V600E and other oncogenic mutations had significantly poorer survival than those with BRAF V600E mutation alone (P = 0.0026). Multivariate cox proportional hazard analysis revealed BRAF V600E and other oncogenic mutations was an independent prognostic factor for OS (HR: 10.559; 95%CI: 1.007-110.656, P = 0.0493). CONCLUSIONS: The BRAF V600E mutation co-existing with other oncogenic mutations but not the BRAF V600E mutation alone was associated with aggressive clinicopathologic features, resulting in poor prognosis in patients with classical PTC. Detection of oncogenic mutations using NGS-based cancer panel testing could enhance understanding of the clinical features of classical PTC.

Cancer gene analysis of liquid-based cytology specimens using next-generation sequencing: A technical report of bimodal DNA- and RNA-based panel application.

BACKGROUND: As liquid-based cytology (LBC) specimens harbor high-quality DNA, genomic analysis using LBC specimens is beneficial for integrative diagnosis. This study aimed to clarify the feasibility of LBC specimens for a bimodal application of DNA- and RNA-based next-generation sequencing (NGS) panels. METHODS: LBC specimens were prepared from cultured human cancer HEC59 cells using commercially available fixatives (Cellprep, CytoRich Red, and SurePath solutions), and were subjected to NGS for a feasibility study. Clinical LBC specimens of thyroid and salivary gland tumors were prepared using CytoRich Red solution. After DNA and RNA extraction, NGS analyses were performed in a single run using combined DNA- and RNA-based custom-made cancer panels for the detection of gene mutations and fusions. RESULTS: High-quality DNA and RNA were obtained, and the expected gene mutations and fusions were detected in HEC59 cells using all types of LBC fixatives. Most available clinical cases (18 out of 20) exhibited pathogenic gene mutations (15 cases) and fusion genes (3 cases) using the bimodal DNA- and RNA-based panels. Overall, 18 cases (90%) showed oncogenic mutations or fusion genes of diagnostic values. CONCLUSION: Simultaneous application of bimodal DNA- and RNA-based gene panels was useful in NGS analysis using residual LBC specimens for integrative diagnosis. Residual LBC specimens for genomic analysis, including fusion gene analysis, are particularly useful for obtaining genomic information before surgical resection.

Renal Cell Carcinoma Metastasizing to the Cricoid Cartilage Presenting With Subglottic Stenosis: A Case Report and Literature Review.

A 72-year-old Japanese man with a 4-month history of hoarseness and 1-week history of difficulty breathing was admitted to our department. He underwent right total nephrectomy for primary clear cell-type renal cell carcinoma (RCC) 6 years ago and left partial nephrectomy for the metastasis 4 years ago. Flexible laryngeal fiberscope examination revealed bilateral subglottic stenosis without obvious mucosal lesions. Enhanced computerized tomography (CT) scan of the neck revealed that the cricoid cartilage had become bilaterally expansive and tumorous lesion exhibiting enhancement. We performed tracheostomy on the appointed day and biopsied the tumor in the cricoid cartilage via the skin incision. Results of histologic and immunohistologic examinations for AE1/AE3, CD10, and vimentin positivity were consistent with clear cell-type RCC. Chest and abdomen CT scans revealed a few tiny metastases in the upper lobe of the left lung but no recurrence in the abdomen. At 2 weeks from the day of tracheostomy, total laryngectomy was performed. Postoperatively, the patient was treated transorally with axitinib (10 mg/day) and as of 12 months he remains alive with unchanging lung metastasis. Next-generation sequencing of targeted regions using a surgical specimen from the tumor revealed a frameshift mutation in the von Hippel-Lindau gene (p.T124Hfs*35) and a missense mutation in the TP53 gene (p.H193R).

Epstein­Barr virus­associated lymphoepithelial carcinoma arising in the parotid gland: A case report and literature review.

A 60-year-old woman presented with a 3-year history of a slow-growing, painless mass in their left parotid gland. Ultrasonography revealed a well-circumscribed, lobulated, hypoechoic mass measuring 19x12x10 mm in the left parotid gland. Computed tomography revealed a well-circumscribed, solid mass with homogeneous enhancement. Fluorodeoxyglucose-positron emission tomography revealed uptake by the tumor but no uptake in other organs, including the nasopharynx. The patient underwent superficial parotidectomy with adequate safety margins and selective neck dissection followed by radiotherapy. No facial paralysis or recurrence of the tumor had been observed as of 20 months post-operation. Histologically, the tumor was composed of sheets of syncytial cancer cells with prominent nucleoli in a dense lymphoplasmacytic background. Epstein-Barr virus (EBV)-encoded RNA in situ hybridization was diffusely positive in the tumor cells. These findings indicated that the tumor was an EBV-associated lymphoepithelial carcinoma. Metastasis, especially from the nasopharynx, was excluded endoscopically and radiologically. Targeted next-generation sequencing of 160 cancer-related genes using the surgical specimen revealed no mutations, including known significant mutations detected in EBV-associated nasopharyngeal carcinoma.

Derivative Chromosome 3 Loss from t(3;6)(q12;q14) Followed by Differential VHL Mutations Underlie Multifocal ccRCC.

BACKGROUND/AIM: The Von Hippel-Lindau (VHL) gene encodes a protein (pVHL) that plays an important role in proteasome degradation of hypoxia inducible factor α (HIFα) through E3 activation. Accumulation of HIFα by loss of functional pVHL promotes tumorigenesis, thus, VHL has tumor suppressor gene capability in clear cell renal cell carcinoma (ccRCC). VHL is the most frequently mutated gene in ccRCC. The complete loss of VHL is mainly achieved by loss of chromosome 3p, which has a VHL coding region in combination with mutation or hypermethylation of the remaining copy of VHL. Given the risk of constitutional chromosome 3 translocation for RCC, it is important to detect the translocation and understand the mechanism underlying the development of multifocal ccRCC. CASE REPORT: A 67-year-old female patient diagnosed with multifocal RCC underwent robot-assisted partial nephrectomy (RAPN) for three kidney tumors. A cancer gene panel test using next generation sequencing (NGS) detected differential VHL mutations (c.533T>G; p.L178R, c.465_466insTA; p.T157Ifs*3, c.343C>A; p.H115N), while VHL mutation was not detected in peripheral blood DNA. A tendency toward copy number loss of genes on der(3) was also detected in all tumors, but not in the germline one. A karyotype analysis revealed a germline translocation between 3 and 6, t(3;6)(q12;q14). CONCLUSION: Chromosome 3 translocation and loss of derivative chromosome containing 3p and subsequent somatic differential VHL mutations in this case strongly support the previously proposed three-step model to explain the development of familial conventional ccRCC.

Two Distinct Neural Mechanisms Underlying Acupuncture Analgesia.

Acupuncture analgesia is a traditional treatment with a long history, although it lacks scientific evidence. It is reportedly associated with the central nervous system, including various brain regions, from the cortices to the brain stem. However, it remains unclear whether the distributed regions behave as a single unit or consist of multiple sub-units playing different roles. Magnetoencephalography is a neuroimaging technique that can measure the oscillatory frequency of neural signals and brain regions. The frequency band of neural signals allows further understanding of the characteristics of the acupuncture-related neural systems. This study measured resting-state brain activity using magnetoencephalography in 21 individuals with chronic pain before and after acupuncture treatment. The subjective level of pain was assessed using a visual analog scale, and brain activity was compared to identify the brain regions and the frequencies associated with acupuncture analgesia. Here, we categorized the changes in resting-state brain activity into two groups: low-frequency oscillatory activity (<3 Hz) in the left middle occipital and right superior partial lobule and high-frequency oscillatory activity (81-120 Hz) on both sides of the prefrontal, primary sensory, and right fusiform gyri. These findings suggest that acupuncture analgesia influences two or more sub-units of the neural systems, which helps us understand the neural mechanisms underlying acupuncture analgesia.

The oligodendroglial histological features are not independently predictive of patient prognosis in lower-grade gliomas.

The relevance of oligodendroglial histological features to patient prognoses is controversial. 93 LrGGs resected for about 2 decades were re-assessed based on WHO2007 with special interest to pure oligodendroglial diagnosis (oligodendroglioma or anaplastic oligodendroglioma) and presence of CFO features. Those histological features, patients OS, and tumor chromosomal/genetic characteristics were correlated each other in each of the 3 IDH-1p/19q-based molecular groups. There was significant association between 1p19q status with the oligodendroglial histological diagnosis as well as presence of CFO in the entire cohort. The oligodendroglial diagnosis was associated with longer OS in IDHmut/codel group; however, this association was not significant in the multivariate analyses. In IDHmut/noncodel and IDH-wildtype groups, the oligodendroglial diagnosis was not associated with patient OS. Presence of CFO was not associated with patient OS in any molecular groups. Gain of 8q was associated with the oligodendroglial diagnosis in IDHmut/noncodel group. Neither the oligodendroglial diagnosis nor CFO was predictive for the methylation status of the MGMT gene in any molecular groups. The oligodendroglial histological features are not independently predictive of either patient prognosis or chemotherapeutic response in LrGGs, leaving the possibility of marginal favorable association only in IDHmut/codel tumors.

Sclerosing Polycystic Adenosis Arising in the Parotid Gland Without PI3K Pathway Mutations.

A 15-year-old old Japanese male with a 2-month history of swelling of his left subauricular area was admitted to our department. A thumb-sized, hard mass with mild tenderness was palpated on the left parotid gland. Ultrasonography revealed a well-circumscribed, hypoechoic mass exhibiting heterogeneity in the left parotid gland measuring 1.7 × 1.5 × 1.3 cm. Computed tomography scan revealed a well-circumscribed, solid mass exhibiting slight peripheral enhancement in the left parotid gland. Magnetic resonance imaging revealed a hypointense mass in the left parotid gland on both T1- and T2-weighted images. Clinicoradiologic findings suggested a benign or low-grade malignant parotid tumor. The patient underwent left superficial parotidectomy with adequate safety margins. The facial nerve was identified and preserved. Neither facial paralysis nor tumor recurrence was observed as of 1 year postoperatively. Histologically, the nodule consisted of a vaguely nodular arrangement of variably sized ducts and acini in a hyalinized fibrous background with focal myxoid changes. The ductal/acinar component exhibited a bilayered arrangement of cuboidal luminal and flattened abluminal cells exhibiting a variety of epithelial proliferative patterns, including micropapillary and cribriform. Areas of oncocyte-like changes with intracellular coarse eosinophilic granules, apocrine-like feature, foamy/vacuolated changes, and clear cells were noted in the proliferating epithelium. Immunohistologically, the luminal cells were positive for gross cystic disease fluid protein-15. The Ki-67 labeling index was 2-3%. The histologic features and immunohistologic profile were consistent with sclerosing polycystic adenosis. Targeted next-generation sequencing of 160 cancer-related genes using the surgical specimen revealed no mutations, including known significant mutations in PTEN, PIK3CA, or PIK3R1.

Prognostic impact of serum procalcitonin in non-small cell lung cancer.

INTRODUCTION: Increased serum procalcitonin (PCT), a well-known biomarker for sepsis, has been reported in several cancer types. We aimed to investigate the prognostic impact of PCT in non-small cell lung cancer (NSCLC). METHODS: Medical records of 51 consecutive patients with NSCLC (Aichi Medical University Hospital) admitted between July 2017 and July 2018 were retrospectively reviewed. The patients were divided into PCT-low (PCT < 0.1 ng/mL) and PCT-high (PCT ⩾ 0.1 ng/mL) groups, and their clinical characteristics and survival were compared. RESULTS: In contrast to the PCT-low group (n = 24), the PCT-high group (n = 27) showed significantly worse Performance Status (PS) and overall survival (OS) (PS 0-2/3-4, 16/8 versus 12/15, p = 0.034; median OS, not reached versus 127 days, p < 0.001), irrespective of the presence of infection (p = 0.785). Multivariate analysis showed that the disease stage (IV versus I-III) and high PCT level (⩾0.1 versus <0.1 ng/mL) were significantly worse prognostic factors with hazard ratios of 3.706 (p = 0.023) and 3.951 (p = 0.010), respectively. CONCLUSION: The results suggest that serum PCT in NSCLC was elevated regardless of the presence of infection. Higher PCT levels are associated with poor PS and shorter OS in NSCLC.

Resection of a desmoid-type fibromatosis with a CTNNB1 p.S45P mutation using a cervico-thoracic approach: A case report and literature review.

Desmoid-type fibromatosis (DF) is a rare, locally infiltrative, and fibroblastic proliferative disease. DF usually arises from abdominal fascial tissue, but in rare cases, it can occur in extra-abdominal areas. A 73-year-old Japanese male complained of a painless, left anterior neck mass of 3-month duration. Computed tomography revealed the mass measured 9 × 7 × 6 cm and extended to the anterior mediastinum, with invasion of the left clavicle. En bloc resection of the tumor with the left sternoclavicular joint and the medial portion of the left clavicle was performed by cervico-thoracic approach with L-shaped partial sternotomy. Histopathologic examination showed fascicular growth of spindle-shaped cells separated by abundant collagen. Immunohistologic examination revealed nuclear staining of ß-catenin and cytoplasmic staining of vimentin. Genetic analysis of 160 cancer-related genes by next-generation sequencing (NGS) demonstrated only a missense mutation in the CTNNB1 gene (c.133T>C, p.S45P). DF extending from the neck to the anterior mediastinum is rare. We report the complete resection of a large-sized DF with the clavicular invasion. A low-frequency CTNNB1 mutation of DF was identified. Genetic analysis with NGS was beneficial for the diagnosis.

Next-generation sequencing in residual liquid-based cytology specimens for cancer genome analysis.

BACKGROUND: Cancer genome profiling of cytology specimens using next-generation sequencing (NGS) requires adequate and good-quality DNA. Genomic examination of cytology samples was conventionally performed on cell block (CB) or smear specimens than on residual liquid-based cytology (LBC) specimens, which are high-quality DNA sources even after long-term storage. METHODS: We estimated tumor fractions of 37 residual LBC specimens, including 30 fine needle aspiration (FNA) samples from the thyroid (12 papillary thyroid carcinomas and two malignant lymphomas), lymph node (13 metastatic carcinomas and one malignant lymphoma), and breast cancer (one phyllodes tumor and one invasive ductal carcinoma), two pancreatic carcinoma samples, and five liquid (ascites, pleural effusion, and cerebrospinal fluid) samples. The DNA was extracted from all samples and subjected to NGS using a customized cancer gene panel comprising 28 cancer-related genes. RESULTS: NGS analysis revealed somatic mutations corresponding to pathological diagnosis with adequate variant allele frequency (VAF) in 24 LBC specimens, which had significantly higher tumor fraction (72.5% ± 4.9%). Ten cases, including the five fluid samples, had very small tumor fractions (7.5% ± 2.3%) to obtain sufficient VAF. Other two samples had high tumor fractions but showed very low VAF, indicating the presence of fusion genes. The remaining one sample yielded no DNA recovery. CONCLUSION: The residual LBC specimens collected by FNA from the thyroid gland and lymph node were verified to carry high tumor fraction and could serve as an alternate source for molecular testing to screen and diagnose cancers without the use of CB or smears.

A post-transcriptional program of chemoresistance by AU-rich elements and TTP in quiescent leukemic cells.

BACKGROUND: Quiescence (G0) is a transient, cell cycle-arrested state. By entering G0, cancer cells survive unfavorable conditions such as chemotherapy and cause relapse. While G0 cells have been studied at the transcriptome level, how post-transcriptional regulation contributes to their chemoresistance remains unknown. RESULTS: We induce chemoresistant and G0 leukemic cells by serum starvation or chemotherapy treatment. To study post-transcriptional regulation in G0 leukemic cells, we systematically analyzed their transcriptome, translatome, and proteome. We find that our resistant G0 cells recapitulate gene expression profiles of in vivo chemoresistant leukemic and G0 models. In G0 cells, canonical translation initiation is inhibited; yet we find that inflammatory genes are highly translated, indicating alternative post-transcriptional regulation. Importantly, AU-rich elements (AREs) are significantly enriched in the upregulated G0 translatome and transcriptome. Mechanistically, we find the stress-responsive p38 MAPK-MK2 signaling pathway stabilizes ARE mRNAs by phosphorylation and inactivation of mRNA decay factor, Tristetraprolin (TTP) in G0. This permits expression of ARE mRNAs that promote chemoresistance. Conversely, inhibition of TTP phosphorylation by p38 MAPK inhibitors and non-phosphorylatable TTP mutant decreases ARE-bearing TNFα and DUSP1 mRNAs and sensitizes leukemic cells to chemotherapy. Furthermore, co-inhibiting p38 MAPK and TNFα prior to or along with chemotherapy substantially reduces chemoresistance in primary leukemic cells ex vivo and in vivo. CONCLUSIONS: These studies uncover post-transcriptional regulation underlying chemoresistance in leukemia. Our data reveal the p38 MAPK-MK2-TTP axis as a key regulator of expression of ARE-bearing mRNAs that promote chemoresistance. By disrupting this pathway, we develop an effective combination therapy against chemosurvival.

Lung Adenocarcinoma with Cheek Dysesthesia as an Initial Symptom: A Case Report and Literature Review.

Metastasis from lung carcinoma to the sphenoid bone is rare. Patients with symptoms related to sphenoid bone metastasis as the initial presentation of carcinoma are thus also rare. Herein, we report the case of a patient presenting with only cheek dysesthesia as the first sign of lung adenocarcinoma. The 74-year-old woman presented with a 2-month history of left cheek dysesthesia. CT showed a tumor around 2.5 cm in diameter with heterogeneous enhancement of the central focus at the left foramen rotundum in the sphenoid bone. We endoscopically biopsied the tumor through the left sphenoid sinus. Results of histologic examination were consistent with lung adenocarcinoma. FDG-PET/CT analysis demonstrated lung carcinoma that had already metastasized to mediastinal lymph nodes and multiple bones, such as the ribs and lumbar vertebras, in addition to the sphenoid bone. As EGFR gene mutation (p.L858R) was identified, the patient was treated with oral gefinitib. This treatment proved quite effective, and the patient remains alive without tumor growth as of 18 months.

Comprehensive validation of liquid-based cytology specimens for next-generation sequencing in cancer genome analysis.

In addition to conventional cytology, liquid-based cytology (LBC) is also used for immunocytochemistry and gene analysis. However, an appropriate method to obtain high quality DNA for next-generation sequencing (NGS) using LBC specimens remains controversial. We determined the optimal conditions for fixation with an alcohol-based fixative for LBC and DNA extraction using cultured cancer cell lines and clinical specimens. The extracted DNA was processed for NGS after the DNA quality was confirmed based on the DNA concentration and degree of degradation. The optimal conditions for cultured cells to obtain high quality DNA were to fix the cells at a density of 6 × 103 or 2 × 104 cells/mL and to use the magnetic bead-based DNA extraction method. Even after storing the fixed cells for 90 days, DNA extracted using the above and other extraction kits, including membrane-based methods, did not undergo degradation. Furthermore, 5-year-old residual LBC samples demonstrated high DNA quality that was suitable for NGS. Furthermore, a cancer genome panel analysis was successfully performed with DNA extracted from cultured cells fixed at 6 × 103 cells/mL for 90 days, and with DNA from residual LBC samples even after 1 year of storage. Residual LBC samples may be a useful source of DNA for clinical NGS to promote genome-based cancer medicine.