Outcomes after sublobar resection versus lobectomy in non-small cell carcinoma in situ.

OBJECTIVE: Guidelines for treatment of non-small cell lung cancer identify patients with tumors ≤2 cm and pure carcinoma in situ histology as candidates for sublobar resection. Although the merits of lobectomy, sublobar resection, and lymphoid (LN) sampling, have been investigated in early-stage non-small cell lung cancer, evaluation of these modalities in patients with IS disease can provide meaningful clinical information. This study aims to compare these operations and their relationship with regional LN sampling in this population. METHODS: The National Cancer Database was used to identify patients diagnosed with non-small cell lung cancer clinical Tis N0 M0 with a tumor size ≤2 cm from 2004 to 2017. The χ2 tests were used to examine subgroup differences by type of surgery. Kaplan-Meier method and Cox proportional hazard model were used to compare overall survival. RESULTS: Of 707 patients, 56.7% (401 out of 707) underwent sublobar resection and 43.3% (306 out of 707) underwent lobectomy. There was no difference in 5-year overall survival in the sublobar resection group (85.1%) compared with the lobectomy group (88.9%; P = .341). Multivariable survival analyses showed no difference in overall survival (hazard ratio, 1.044; P = .885) in the treatment groups. LN sampling was performed in 50.9% of patients treated with sublobar resection. In this group, LN sampling was not associated with improved survival (84.9% vs 85.0%; P = .741). CONCLUSIONS: We observed no difference in overall survival between sublobar resection and lobectomy in patients with cTis N0 M0 non-small cell lung cancer with tumors ≤2 cm. Sublobar resection may be an appropriate surgical option for this population. LN sampling was not associated with improved survival in patients treated with sublobar resection.

Displasia epitelial corneal / Corneal epithelial dysplasia

Las neoplasias intraepiteliales córneo-conjuntival son lesiones premalignas, mal delimitadas, de crecimiento lento y escaso potencial de malignización. Solo el 9 por ciento progresa a carcinoma invasor de células escamosas. Posee varias formas de presentación y tiene múltiples dilataciones vasculares. La displasia epitelial corneal primaria es una forma poco frecuente de neoplasia intraepitelial córnea-epitelial. Se presenta un caso clínico confirmado por estudios anatomopatológicos. En el presente estudio se observó respuesta satisfactoria luego de un mes de tratamiento tópico con 5FU, sin efectos colaterales. El seguimiento durante tres años no ha mostrado signos de recidiva(AU)

Corneal-conjunctival intraepithelial neoplasms are premalignant, poorly demarcated, slow-growing lesions with low malignant potential. Only the 9 percent progresses to invasive squamous cell carcinoma. It appears in several forms and presents multiple vascular dilatations. Primary corneal epithelial dysplasia is a rare form of corneal-epithelial intraepithelial neoplasia. We present a clinical case, confirmed by anatomopathologic studies. In the present study we observed a satisfactory response after one month of topical treatment with 5FU, with no side effects. Follow-up for three years has shown no signs of recurrence(AU)

Histopathological Characteristics and Therapeutic Outcomes of Endoscopic Submucosal Dissection for Gastric High-Grade Intraepithelial Neoplasia.

Background: The endoscopic resection of suspected gastric high-grade intraepithelial neoplasia (HGIN) may incidentally cause the patient to suffer from early gastric cancer (EGC), complicating the subsequent clinical management. Identifying the risk factors for such misstaging may help guide the clinical management. Methods: The information obtained from 123,460 patients, who underwent conventional upper gastrointestinal endoscopy at the First Affiliated Hospital of Nanjing Medical University from January 2010 to December 2015, were retrospectively reviewed. Patients with an initial diagnosis of HGIN underwent endoscopic submucosal dissection (ESD), and received a final diagnosis of EGC. The risk factors for the upgraded pathology and noncurative resection were analyzed. Results: Among the 134 patients initially diagnosed with HGIN, 35 (26.12%) patients were finally diagnosed with EGC after ESD. A lesion size of ≥2 cm (odds ratio [OR] = 5.16, 95% confidence interval [CI] = 2.04-13.05; P < .01), ≤4 biopsies taken (OR = 2.73, 95% CI = 1.15-6.48; P < .05), and the presence of upper gastrointestinal bleeding (UGIB; OR = 15.64, 95% CI = 1.29-189.75; P < .05) were the independent risk factors for upgraded pathology. In addition, patients >65 years old (OR = 0.022, 95% CI = 0.901-6.549; P < .05) or with a lesion size of ≥2 cm (OR = 4.237, 95% CI = 1.650-10.878; P < .01) were more likely to endure the noncurative resection. Conclusion: For suspected gastric HGIN patients, age, lesion size, the number of biopsies, and UGIB should be taken into account before deciding on the ESD.

Risk factors for esophageal squamous cell carcinoma and its histological precursor lesions in China: a multicenter cross-sectional study.

BACKGROUND: Despite research efforts, the causative factors that contribute to esophageal squamous cell carcinoma (ESCC) in high-risk areas have not yet been understood. In this study, we, therefore, aimed to describe the risk factors associated with ESCC and its precursor lesions. METHODS: We performed an endoscopic examination of 44,857 individuals aged 40-69 years from five high incidence regions of China in 2017-2018. Participants were classified as 4 groups of normal control, esophagitis, low-grade intraepithelial neoplasia (LGIN) and high-grade intraepithelial neoplasia/esophageal squamous cell carcinoma (HGIN/ESCC) using an unconditional logistic regression determine risk factors. RESULTS: We identified 4890 esophagitis, 1874 LGIN and 437 HGIN/ESCC cases. Crude odds ratios (ORs) and adjusted odds ratios were calculated using unconditional logistic regression. Drinking well and surface water, salty diet, and positive family history of cancer were the common risk factors for esophagitis, LGIN and HGIN/ESCC. History of chronic hepatitis/cirrhosis was the greatest risk factor of esophagitis (adjusted OR 2.96, 95%CI 2.52-3.47) and HGIN/ESCC (adjusted OR 1.91, 95%CI 1.03-3.22). Pesticide exposure (adjusted OR 1.20, 95%CI 1.05-1.37) was essential risk factor of LGIN. CONCLUSIONS: Among individuals aged 40-69 years in high incidence regions of upper gastrointestinal cancer, the results provided important epidemiological evidence for the prevention of different precancerous lesions of ESCC.

On the origin of germ cell neoplasia in situ: Dedifferentiation of human adult Sertoli cells in cross talk with seminoma cells in vitro.

Germ cell neoplasia in situ (GCNIS) is the noninvasive precursor of testicular germ cell tumors type II, the most common cancer in young men, which originates from embryonic germ cells blocked in their maturation. GCNIS is associated with impaired Sertoli cells (SCs) that express fetal keratin 18 (KRT18) and the pluripotency factor SRY-Box transcription factor 2 (SOX2). According to the current theory concerning the origin of GCNIS, these SCs are prepubertal cells arrested in their maturation due to (epi)genetic anomalies and/or environmental antiandrogens. Thus, they are unable to support the development of germ cells, which leads to their maturational block and further progresses into GCNIS. Alternatively, these SCs are hypothesized to be adult cells dedifferentiating secondarily under the influence of GCNIS. To examine whether tumor cells can dedifferentiate SCs, we established a coculture model of adult human SCs (FS1) and a seminoma cell line similar to GCNIS (TCam-2). After 2 wk of coculture, FS1 cells showed progressive expression of KRT18 and SOX2, mimicking the in vivo changes. TCam-2 cells showed SOX2 expression and upregulation of further pluripotency- and reprogramming-associated genes, suggesting a seminoma to embryonal carcinoma transition. Thus, our FS1/TCam-2 coculture model is a valuable tool for investigating interactions between SCs and seminoma cells. Our immunohistochemical and ultrastructural studies of human testicular biopsies with varying degrees of GCNIS compared to biopsies from fetuses, patients with androgen insensitivity syndrome, and patients showing normal spermatogenesis further suggest that GCNIS-associated SCs represent adult cells undergoing progressive dedifferentiation.

Transforming acidic coiled-coil protein-3: a novel marker for differential diagnosis and prognosis prediction in endocervical adenocarcinoma.

BACKGROUND: Endocervical adenocarcinoma (ECA) is further classified as human papillomavirus (HPV)-associated (HPVA) or non-HPVA (NHPVA), per the International Endocervical Adenocarcinoma Criteria and Classification (IECC). HPVA is a glandular tumor with stromal invasion and/or exophytic expansile-type invasion, associated with the typical molecular characteristics of high-risk HPV (HR-HPV) infection. Transforming acidic coiled-coil protein-3 (TACC3),an oncogene that is frequently abnormally expressed,represents a vital biomarker for multiple human malignancies. This study aimed to examine the role of TACC3 in the diagnosis and prognosis of ECA. METHODS: We analyzed 264 patients with ECA who underwent surgical resection, classifying their tumors into HPVA and NHPVA subtypes. The expression levels of TACC3, P16, MLH1, PMS2, MSH2, MSH6 and Ki-67 in tumors were evaluated by tissue microarray using immunohistochemistry (IHC). HPV subtypes were identified in formalin-fixed paraffin-embedded (FFPE) ECA tissues by the polymerase chain reaction (PCR). RESULTS: ECA samples showed increased TACC3 expression relative to adjacent non-carcinoma samples. TACC3 expression was higher in HPVA than in NHPA. In the HPVA subtype, high TACC3 expression was significantly correlated with P16-positive, Ki-67-high expression. Furthermore, TACC3 levels were significantly related to tumor histological type (P = 0.006), nerve invasion (P = 0.003), differentiation (P = 0.004), surgical margin (P = 0.012), parametrium invasion (P = 0.040), P16 expression (P < 0.001), and Ki-67 (P = 0.004). Additionally, Kaplan-Meier analysis showed that TACC3 upregulation was associated with poor overall survival (OS, P = 0.001), disease-free survival (DFS, P < 0.001), and recurrence survival (P < 0.001). Multivariate analysis indicated that elevated TACC3 expression served as a marker to independently predict ECA prognosis. ROC curve analyses indicated that TACC3, P16, and HPV subtypes showed similar utility for distinguishing HPVA from NHPVA, with areas under the ROC curves of 0.640, 0.649, and 0.675, respectively. The combination of TACC3 and HPV subtypes improved the diagnostic performance of ECA compared with TACC3, P16, and HPV subtypes alone. CONCLUSIONS: Taken together, our findings identify that TACC3 is a promising complementary biomarker for diagnosis and prognosis for patients with ECA.

RPL34-AS1-induced RPL34 inhibits cervical cancer cell tumorigenesis via the MDM2-P53 pathway.

Ribosomal proteins (RPs) are important components of ribosomes and related to the occurrence and development of tumors. However, little is known about the effects of the RP network on cervical cancer (CC). In this study, we screened differentially expressed RPL34 in CC by high-throughput quantitative proteome assay. We found that RPL34 acted as a tumor suppressor and was downregulated in CC and inhibited the proliferation, migration, and invasion abilities of CC cells. Next, we verified that RPL34 regulated the CC through the MDM2-P53 pathway by using Act D medicine, MDM2 inhibitor, and a series of western blotting（WB）assays. Moreover, an antisense lncRNA, RPL34-AS1, regulated the expression of RPL34 and participated in the tumorigenesis of CC. RPL34 can reverse the effect of RPL34-AS1 in CC cells. Finally, by RNA-binding protein immunoprecipitation (RIP) assay we found that eukaryotic initiation factor 4A3 (EIF4A3), which binds to RPL34-AS1, regulated RPL34-AS1 expression in CC. Therefore, our findings indicate that RPL34-AS1-induced RPL34 inhibits CC cell proliferation, invasion, and metastasis through modulation of the MDM2-P53 signaling pathway, which provides a meaningful target for the early diagnosis and treatment of CC.

Vulvar Intraepithelial Neoplasia: A Review of the Disease and Current Management.

IMPORTANCE: Vulvar intraepithelial neoplasia (VIN) represents an increasingly common, yet challenging diagnosis that shares many common risk factors with cervical intraepithelial neoplasia. However, unlike cervical intraepithelial neoplasia, effective screening and treatment strategies are much less defined for patients with VIN. OBJECTIVE: The objective of this article is to review the underlying risk factors leading to the development of VIN, identify special populations at risk for VIN, and outline acceptable treatment strategies. EVIDENCE ACQUISITION: This literature review was performed primarily using PubMed. RESULTS: Vulvar intraepithelial neoplasia can be separated into usual VIN (uVIN) and differentiated VIN (dVIN). The more common uVIN is related to underlying human papillomavirus infection, whereas dVIN occurs in the setting of other vulvar inflammatory conditions such as lichen sclerosis. Differentiated VIN carries a higher risk of progression to invasive malignancy. Extramammary Paget disease is a rare intraepithelial adenocarcinoma unrelated to uVIN and dVIN, although management is similar. CONCLUSIONS AND RELEVANCE: Vulvar intraepithelial neoplasia is a preinvasive neoplasia of the vulva with few robust strategies for surveillance or management. Careful examination with targeted biopsy is warranted for suspicious lesions, and a combination of surgical and medical management can be tailored for individual patient needs.

Whole-Exome and Transcriptome Analysis of UV-Exposed Epidermis and Carcinoma In Situ Reveals Early Drivers of Carcinogenesis.

Squamous cell carcinoma in situ (SCCIS) is a prevalent precancerous lesion that can progress to cutaneous squamous cell carcinoma. Although SCCIS is common, its pathogenesis remains poorly understood. To better understand SCCIS development, we performed laser captured microdissection of human SCCIS and the adjacent epidermis to isolate genomic DNA and RNA for next-generation sequencing. Whole-exome sequencing identified UV-signature mutations in multiple genes, including NOTCH1-3 in the epidermis and SCCIS and oncogenic TP53 mutations in SCCIS. Gene families, including SLFN genes, contained UV/oxidative-signature disruptive epidermal mutations that manifested positive selection in SCCIS. The frequency and distribution of NOTCH and TP53 mutations indicate that NOTCH mutations may precede TP53 mutations. RNA sequencing identified 1,166 differentially expressed genes; the top five enriched gene ontology biological processes included (i) immune response, (ii) epidermal development, (iii) protein phosphorylation, (iv) regulation of catalytic activity, and (v) cytoskeletal regulation. The NEURL1 ubiquitin ligase, which targets Notch ligands for degradation, was upregulated in SCCIS. NEURL1 protein was found to be elevated in SCCIS suggesting that increased levels could represent a mechanism for downregulating Notch during UV-induced carcinogenesis. The data from DNA and RNA sequencing of epidermis and SCCIS provide insights regarding SCCIS formation.

Histological criteria for "intraepithelial squamous cell carcinoma" of the esophagus: continued dialogue between Ukrainian and Japanese pathologists.

BACKGROUND: Patients with esophageal squamous cell carcinoma (SCC) have a poor prognosis mostly due to the late diagnosis. A morphological method is still the main diagnostic method for SCC. The aim of the study was to find out which histological criteria, namely Western or Japanese criteria, for early stage SCC are used by pathologists in Ukraine as compared with their Japanese colleagues. METHODS: 14 Ukrainian and 6 Japanese pathologists have participated in this study. Virtual slides for research were provided by National Cancer Research Center (Tokyo, Japan) in 2018. Each of the pathologists has used these slides and presented the conclusion via the Internet. RESULTS: Essential diagnostic discrepancies were revealed: a number of biopsy specimens was diagnosed by Japanese pathologists as "noninvasive carcinoma", while Ukrainian pathologists classified the specimens as high-grade or low-grade dysplasia, indefinite for neoplasia, or reactive/regenerative lesions. CONCLUSION: The adoption of a unified concept of criteria for non-invasive (intraepithelial) carcinoma underlies early endoscopic/surgical treatment, which significantly increases the survival rate of patients with SCC. A solid common approach to the diagnosis between Western and Japanese pathologists, as well as endoscopists, is necessary to ensure timely treatment and increase survival rate of patients with SCC.

Association of antiretroviral therapy with anal high-risk human papillomavirus, anal intraepithelial neoplasia, and anal cancer in people living with HIV: a systematic review and meta-analysis.

BACKGROUND: The effect of antiretroviral therapy (ART) on the natural history of anal high-risk HPV and anal lesion progression is not well established. We reviewed the association of ART and other HIV-related factors on anal HPV infection, anal intraepithelial neoplasia (AIN), and anal cancer among people living with HIV. METHODS: For this systematic review and meta-analysis, we searched MEDLINE and EMBASE for studies published between Jan 1, 1996, and Oct 30, 2019, that reported the association of HIV-related exposures (ART or highly active ART [HAART], HIV-RNA plasma viral load [PVL], and nadir or current CD4 cell count) with outcomes of anal high-risk HPV prevalence, incidence, and persistence; prevalence, incidence, progression, or regression of anal histological and cytological abnormalities; and anal cancer incidence. Effect estimates were extracted whenever available; otherwise, they were calculated from raw data. We assessed the risk of bias of included studies using the Newcastle-Ottawa scale, and random-effects meta-analyses were done to examine heterogeneity using the I2 statistic. This study is registered on the PROSPERO database, CRD42018007271. FINDINGS: We identified 6777 studies, of which 5377 were excluded before full-text review. 122 studies providing estimates for 130 distinct populations matched the inclusion criteria. The populations comprised 417 006 people living with HIV (women, men who have sex with men, and men who have sex with women). 41 (32%) population estimates were not stratified by sex or sexual orientation. People living with HIV receiving ART had 35% lower high-risk HPV prevalence than ART-naive people (crude odds ratio [OR] 0·65, 95% CI 0·54-0·79; I2 12·1%, p=0·31) in 18 studies, and prolonged ART use was associated with a 10% reduction per year in high-risk HPV prevalence in two studies (adjusted OR 0·90, 0·85-0·95; I2 0%, p=0·88). People living with HIV with undetectable PVL had lower HSIL-AIN2+ prevalence than those with detectable PVL (crude OR 0·84, 0·72-0·98; I2 0%, p=0·80) in 16 studies, particularly if sustained for more than 1 year (crude OR 0·62, 0·47-0·81; I2 0%, p=0·51). ART was not associated with anal cancer incidence when adjusted for years living with HIV in three studies (adjusted hazard ratio [HR] 1·11, 95% CI 0·68-1·80; I2 0%, p=0·57), but ART users with sustained undetectable HIV PVL had 44% lower risk of anal cancer than those without (adjusted HR 0·56, 0·44-0·70; I2 0%, p=0·94) and for each increase in nadir CD4 cell counts of 100 cells per µL, there was a 40% decrease in anal cancer incidence (crude HR 0·60, 0·46-0·78; I2 21·7%, p=0·26). INTERPRETATION: Effective ART use and early initiation at high nadir CD4 counts might reduce anal high-risk HPV infection and anal cancer risk. Although most studies were cross-sectional in design and few adjusted for potential confounders, this analysis provides comprehensive estimates of the effect of ART and HIV-related factors on the natural history of anal HPV-related disease in people living with HIV. FUNDING: EU Marie Sklodowska-Curie Actions programme.

Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas.

the bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin. Consequently, preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of molecular, histological and pathophysiological features. Intraepithelial neoplasms are reported in biliary tract, as biliary intraepithelial neoplasm (BilIN), and in pancreas, as pancreatic intraepithelial neoplasm (PanIN). Both can evolve to invasive carcinomas, respectively cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary neoplasms arise in biliary tract and pancreas. Intraductal papillary neoplasm of the biliary tract (IPNB) share common histologic and phenotypic features such as pancreatobiliary, gastric, intestinal and oncocytic types, and biological behavior with the pancreatic counterpart, the intraductal papillary mucinous neoplasm of the pancreas (IPMN). All these neoplastic lesions exhibit similar immunohistochemical phenotypes, suggesting a common carcinogenic process. Indeed, CCA and PDAC display similar clinic-pathological features as growth pattern, poor response to conventional chemotherapy and radiotherapy and, as a consequence, an unfavorable prognosis. The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells.

Human Papillomavirus-Independent Squamous Lesions of the Vulva.

The pathogenesis of vulvar squamous neoplasia has 2 pathways: human papillomavirus (HPV)-dependent and HPV-independent. The HPV-dependent pathway in the vulva follows the same progression as HPV-dependent lesions elsewhere in the gynecologic tract-HPV infection results in high-grade squamous intraepithelial lesion with subsequent progression to basaloid squamous cell carcinoma. The HPV-independent pathway is more complex, with a variety of precursor lesions and molecular alterations. Although the most recognized form of HPV-independent vulvar lesion is differentiated vulvar intraepithelial neoplasia, recent explorations have elucidated new precursors. This review provides an update on HPV-independent risk factors and precursor lesions for squamous cell carcinoma of the vulva.

High-risk Human Papilloma Virus Testing Improves Diagnostic Performance to Predict Moderate- to High-grade Anal Intraepithelial Neoplasia in Human Immunodeficiency Virus-infected Men Who Have Sex With Men in Low-to-Absent Cytological Abnormalities.

BACKGROUND: Screening methods for anal squamous intraepithelial lesions (SILs) are suboptimal. We aimed to determine the diagnostic performance of a composite endpoint comprising anal liquid-based cytology (aLBC) and high-risk human papillomavirus (HR-HPV) testing to predict histological high-grade SILs (hHSILs). METHODS: From the SeVIHanal cohort, human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) who had an aLBC with concomitant HR-HPV testing were included. hHSILs were determined by high-resolution anoscopy (HRA)-guided biopsy. RESULTS: A total of 705 visits obtained from 426 patients were included. The prevalence of HR-HPV among aLBC results were 51.9% (133/215) normal, 87.9% (20/232) low-grade SILs (LSILs), and 90.9% (149/164) high-grade SILs; P (linear association) < .001. Low prevalence of hHSILs was only observed for the composite aLBC/HR-HPV testing endpoint "normal/noHR-HPV" (10%) and "LSIL/noHR-HPV" (4%). The prognostic values (95% confidence interval) for HR-HPV to predict hHSILs in normal cytology were positive predictive value (PPV), 29.3% (25.6%-33.3%); negative predictive value (NPV), 90.2% (82.8%-94.7%); sensitivity, 83% (69.2%-92.4%); and specificity, 44.1% (36.4%-51.9%). Corresponding figures for cytologic LSILs were PPV, 39.2% (37.4%-41.1%); NPV, 96.4% (78.9%-99.5%); sensitivity, 98.8% (93.3%-99.9%); and specificity, 17.9% (12.1%-24.9%). A positive interaction and a synergistic effect for the composite endpoint were observed (relative excess risk = 1.50, attributable proportion of histological results to interaction = 0.17, synergy index = 1.24). CONCLUSIONS: HRA should not be indicated in the setting of LSILs/noHR-HPV following aLBC-based screening. In contrast, HIV-infected MSM with normal aLBC/HR-HPV infection should be considered for HRA. CLINICAL TRIALS REGISTRATION: NCT03713229.

Vulvar Cancer as a Result of GATA2 Deficiency, a Rare Genetic Immunodeficiency Syndrome.

BACKGROUND: Vulvar cancer has become more prevalent, and its causes include chronic dermatoses and human papillomavirus (HPV)-mediated disease. Younger immunocompromised women can also be affected. We describe a case of vulvar carcinoma as a result of GATA2 deficiency. CASE: A 19-year-old woman presented to our gynecologic oncology clinic for management of a large vulvar mass. She was diagnosed with stage IB vulvar carcinoma after vulvectomy. GATA2 deficiency was the contributing factor causing vulvar carcinoma. CONCLUSION: GATA2 deficiency causes immunodeficiency in young women, and patients with early-onset HPV-related disease, a family or personal history of leukemia, recurrent infection, or immune irregularities should be screened. Health care providers for these women are often obstetrician-gynecologists, who can provide diagnosis, treatment, referral, and prevention of HPV-related diseases.

[Beyond actinic keratoses: Field cancerization of the skin]. / Au-delà des kératoses actiniques, le champ de cancérisation cutané.

Lesions occurring in actinic keratoses (AK) form erythematous, squamous, crusty and keratotic papules that appear on skin chronically exposed to the sun due to ultraviolet radiation. They are formed by the proliferation of atypical keratinocytes limited to the epidermis and may progress to squamous cell carcinoma in situ and to cutaneous squamous cell carcinoma (CEC). Although low, the metastatic risk associated with the CEC is not negligible. The concept of field cancerization was introduced in 1953 following studies of neoplastic lesions of the oral mucosa. A cancer field is a normal-looking pre-tumoral zone with subclinical, multifocal anomalies, which may constitute a base for new neoplastic lesions. Such fields are frequently seen in areas of photo-exposed skin and around the edges of AK and CEC. In this event, treatment should not be limited to visible or palpable AK lesions, and if a cancer field is suspected, treatment involving the physical destruction or elimination of atypical keratinocytes from the entire area should be considered. Such an approach may improve the long-term prognosis, reduce treatment costs and ensure optimal cosmetic outcome.

Loss of Tight Junction Protein Claudin 18 Promotes Progressive Neoplasia Development in Mouse Stomach.

BACKGROUND & AIMS: Loss of claudin 18 (CLDN18), a membrane-spanning tight junction protein, occurs during early stages of development of gastric cancer and associates with shorter survival times of patients. We investigated whether loss of CLDN18 occurs in mice that develop intraepithelial neoplasia with invasive glands due to infection with Helicobacter pylori, and whether loss is sufficient to promote the development of similar lesions in mice with or without H pylori infection. METHODS: We performed immunohistochemical analyses in levels of CLDN18 in archived tissues from B6:129 mice infected with H pylori for 6 to 15 months. We analyzed gastric tissues from B6:129S5-Cldn18tm1Lex/Mmucd mice, in which the CLDN18 gene was disrupted in gastric tissues (CLDN18-knockout mice), or from control mice with a full-length CLDN18 gene (CLDN18+/+; B6:129S5/SvEvBrd) or heterozygous disruption of CLDN18 (CLDN18+/-; B6:129S5/SvEvBrd) that were infected with H pylori SS1 or PMSS1 at 6 weeks of age and tissues collected for analysis at 20 and 30 weeks after infection. Tissues from CLDN18-knockout mice and control mice with full-length CLDN18 gene expression were also analyzed without infection at 7 weeks and 2 years after birth. Tissues from control and CLDN18-knockout mice were analyzed by electron microscopy, stained by conventional methods and analyzed for histopathology, prepared by laser capture microdissection and analyzed by RNAseq, and immunostained for lineage markers, proliferation markers, and stem cell markers and analyzed by super-resolution or conventional confocal microscopy. RESULTS: CLDN18 had a basolateral rather than apical tight junction localization in gastric epithelial cells. B6:129 mice infected with H pylori, which developed intraepithelial neoplasia with invasive glands, had increasing levels of CLDN18 loss over time compared with uninfected mice. In B6:129 mice infected with H pylori compared with uninfected mice, CLDN18 was first lost from most gastric glands followed by disrupted and reduced expression in the gastric neck and in surface cells. Gastric tissues from CLDN18-knockout mice had low levels of inflammation but increased cell proliferation, expressed markers of intestinalized proliferative spasmolytic polypeptide-expressing metaplasia, and had defects in signal transduction pathways including p53 and STAT signaling by 7 weeks after birth compared with full-length CLDN18 gene control mice. By 20 to 30 weeks after birth, gastric tissues from uninfected CLDN18-knockout mice developed intraepithelial neoplasia that invaded the submucosa; by 2 years, gastric tissues contained large and focally dysplastic polypoid tumors with invasive glands that invaded the serosa. CONCLUSIONS: H pylori infection of B6:129 mice reduced the expression of CLDN18 early in gastric cancer progression, similar to previous observations from human gastric tissues. CLDN18 regulates cell lineage differentiation and cellular signaling in mouse stomach; CLDN18-knockout mice develop intraepithelial neoplasia and then large and focally dysplastic polypoid tumors in the absence of H pylori infection.