Reiko Furuta

Predicting the progression of cervical precursor lesions by human papillomavirus genotyping: A prospective cohort study

Only a subset of cervical precursor lesions progress to cervical cancer and because of the lack of the predictive markers, it cannot be ascertained which lesions will progress or not. To estimate the risk of disease progression associated with human papillomavirus (HPV) genotypes, we followed 570 Japanese women with cytological LSIL (low‐grade squamous intraepithelial lesion) and histological CIN (cervical intraepithelial neoplasia) grade 1–2 lesions (479 CIN 1; 91 CIN 2) at 3 to 4 month intervals for a mean follow‐up period of 39.1 months. At entry, we detected HPV DNA in cervical samples by polymerase chain reaction‐based methodology. Over the period of follow‐up period, 46 lesions progressed to CIN 3 while 362 regressed to normal cytology. Women with multiple HPV infections were more likely to have persistent lesions (hazard ratio [HR] for regression, 0.65; 95% confidence interval [CI], 0.42–1.02; p = 0.07); however, multiple infections did not increase the risk of progression (HR for progression, 1.04; 95% CI, 0.37–2.94; p = 0.94). After adjusting for CIN grade and womens age, HRs for progression to CIN 3 (vs. women with low‐risk types or negative for HPV DNA) varied markedly by HPV genotype: type 16 (11.1, 95% CI: 1.39–88.3); 18 (14.1, 0.65–306); 31 (24.7, 2.51–243); 33 (20.3, 1.78–231); 35 (13.7, 0.75–251); 52 (11.6, 1.45–93.3); 58 (8.85, 1.01–77.6); other high‐risk types (4.04, 0.47–34.7). HPV 45 was not detected in our study subjects. The cumulative probability of CIN 3 within 5 years was 20.5% for HPV 16, 18, 31, 33, 35, 52 and 58; 6.0% for other high‐risk types; 1.7% for low‐risk types (p = 0.0001). In conclusion, type‐specific HPV testing for women with LSIL/CIN 1–2 lesions is useful for identifying populations at increased or decreased risk of disease progression.

High K-ras mutation rates in goblet-cell-type adenocarcinomas of the lungs

Adenocarcinomas of the lungs show a variable histology. We have subclassified such lesions into five cell types: hobnail, columnar, polygonal, mixed and goblet cell types, and investigated their relationships with K-ras mutations. Codons 12, 13 and 61 of the K-ras gene in 120 surgically resected pulmonary adenocarcinomas were examined by the mutation-allele-specific amplification method. Point mutations were observed in 10% of the adenocarcinomas limited to K-ras codon 12 and the commonest base substitution (nine cases) was a G to T transversion. Of the five types, goblet cell lesions demonstrated the highest mutation index, which at 100% (6/6) was significantly different from that of all other cell types. No relationship between K-ras mutation and cigarette smoking was observed. From these findings, it appears that development of goblet-cell-type adenocarcinomas of the lung may involve different carcinogenic mechanisms from adenocarcinomas of other subtypes.

Prevalence of human papillomavirus in mobile tongue cancer with particular reference to young patients

The carcinogenetic role of human papillomavirus (HPV) in mobile tongue cancer remains unclear because of conflicting results reported in the literature. This disparity is likely to be due to variations in the samples and methods used. Furthermore, despite a tendency for increased prevalence of mobile tongue cancer in young adults, only a few reports specifically in young patients have been published. In the present study on 32 patients, including six in their 20s, we genotyped the prevalence of HPV using a highly sensitive detection tool in fresh‐frozen samples from surgical specimens and a novel detection device with electrochemical DNA chip and loop‐mediated isothermal amplification. In addition, we confirmed HPV prevalence by in situ hybridization and immunohistochemistry for the p16INK4a protein, regarded as a biomarker of HPV‐associated cancers. The frequency of 13 genotypes of high‐risk HPV was 0/32 (0%), which was further confirmed by in situ hybridization. Overexpression of p16INK4a protein was observed in six of the 32 patients (19%), with four (67%) also overexpressing p53. Because there is usually a lack of p53 overexpression in HPV‐associated cancer, it is unlikely that p16INK4a protein overexpression is correlated with HPV infection. Consequently, it is unlikely that HPV infection plays an important role in mobile tongue carcinogenesis, in particular in young adults. In addition, our data suggest that the overexpression of p16INK4a protein is not an appropriate biomarker for HPV association in mobile tongue carcinogenesis. (Cancer Sci 2012; 103: 161–168)

Tobacco smoking and regression of low-grade cervical abnormalities

The role of tobacco smoking in the multistage carcinogenesis at the cervix is not fully understood because of a paucity of prospective data. To assess the relationship between smoking and spontaneous regression of cervical precursor lesions, a total of 516 women with low‐grade squamous intraepithelial lesion (LSIL) were monitored by cytology and colposcopy every 4 months. Probability of LSIL regression within 2 years was analyzed in relation to smoking behaviors, with regression defined as at least two consecutive negative Pap smears and normal colposcopy. Women’s age, initial biopsy results, and human papillomavirus (HPV) genotypes were included in the multivariate models for adjustments. Our study subjects included 258 never‐smokers and 258 smokers (179 current and 79 former smokers). During a mean follow‐up time of 39.8 months, 320 lesions regressed to normal cytology. Probability of regression within 2 years was significantly lower in smokers than in never‐smokers (55.0%vs 68.8%, P = 0.004). The risk of LSIL persistence increased with smoking intensity and duration and with younger age at starting smoking (P = 0.003, P < 0.001, and P = 0.03, respectively). Smokers had twice as high a risk of persistent HPV infection compared to never‐smokers (odds ratio, 2.50; 95% confidence interval, 1.30–4.81; P = 0.006). In young women, passive smoking since childhood reduced probability of regression within 2 years (56.7%vs 85.9%, P < 0.001). Further adjustments for a wide range of cervical cancer risk factors did not change the findings. In conclusion, tobacco smoking may interfere with regression of cervical precursor lesions. Childhood exposure to second‐hand smoke may increase a risk of persistent cervical abnormalities among young women. (Cancer Sci 2010)

Early invasive cervical adenocarcinoma: its potential for nodal metastasis or recurrence

Objective To investigate the potential for nodal spread or recurrence in patients with early invasive cervical adenocarcinoma. The possible application of the International Federation of Gynecology and Obstetrics (FIGO) classification (1994) to this variant was also examined.

Mixed squamous cell and glandular papilloma of the lung: A case study and literature review

Mixed squamous cell and glandular papilloma (mixed papilloma) of the lung is an extremely rare neoplasm, with only 10 cases reported so far in the English literature. We present a case study of endobronchial mixed papilloma with immunohistochemical and etiological investigations. A 49‐year‐old male with a smoking history complained of hemoptysis, presented with a lung mass closely adjacent to large vessels in the computed tomography findings, and underwent lobectomy. The 3.0‐cm sized polypoid tumor was histologically diagnosed as endobronchial mixed papilloma. Immunohistochemically, intracellular mucin was positive for MUC5AC, which is expressed in tracheobronchial goblet cells. CAM5.2 and CK19 were diffusely positive, indicating that the tumor originated from the columnar epithelium by squamous metaplasia. CEA and CA19‐9 were focally positive. A human papillomavirus (HPV) investigation with in situ hybridization using a wide spectrum probe and a newly‐developed PCR system did not detect any HPV infection. Including this case with a detailed HPV investigation, all of the reported cases of mixed papilloma were HPV‐negative, and a literature review including newly‐reported cases indicated a high frequency of smoking in such cases. Endobronchial mixed papillomas might have a smoking‐related etiology.

Loss of heterozygosity and the smoking index increase with decrease in differentiation of lung adenocarcinomas: etiologic implications.

To better understand causative relations of smoking to lung adenocarcinomas, the frequency of loss of heterozygosity (LOH) of all autosomal chromosomes was compared among the three grades of histological differentiation with 119 pulmonary adenocarcinomas (AC) and 41 squamous cell carcinomas (SCC), using Southern blotting. The fractional allelic loss (FAL) values, defined as (number of chromosome arms with LOH)/(number of informative arms), and smoking index (a product of number of cigarettes per day and duration in years) for all ACs were 0.19 and 520 whereas those for SCCs were 0.34 and 1,160, respectively. Those for well- (n=33), moderately (n=63) and poorly (n=23) differentiated ACs were 0.100, 0.197, 0.295 and 310, 480, 1,010, respectively. These results showed that less differentiated ACs are more similar to SCC in terms of LOH frequency and smoking.

Neutralizing Antibodies against Human Papillomavirus Types 16, 18, 31, 52, and 58 in Serum Samples from Women in Japan with Low-Grade Cervical Intraepithelial Neoplasia

ABSTRACT We have very limited information on serum neutralizing antibody in women naturally infected with the human papillomaviruses (HPVs) that are causally associated with cervical cancer. In this study, serum samples collected from 217 Japanese women with low-grade cervical intraepithelial neoplasia were examined for their neutralizing activities against HPV16, -18, -31, -52, and -58 pseudovirions. Eighty-four patients (39%), 35 patients (16%), 17 patients (8%), and 1 patient were positive for neutralizing antibodies against one, two, three, and four of these types, respectively. Presence of neutralizing antibody did not always correlate with detection of HPV DNA in cervical swabs collected at the time of blood collection. The neutralizing titers of the majority of sera, ranging between 40 and 640, were found to be conserved in the second sera, collected 24 months later, independently of emergence of HPV DNA in the second cervical swabs. The data strongly suggest that HPV infection induces anti-HPV neutralizing antibody at low levels, which are maintained for a long period of time.

HLA class II DRB1*1302 allele protects against progression to cervical intraepithelial neoplasia grade 3: a multicenter prospective cohort study.

Objective Genetic variations in human leukocyte antigens (HLA) class II regions may influence the risk of cervical cancer by altering the efficiency of the immune responses to human papillomavirus antigens. This prospective study was designed to evaluate the effects of HLA class II alleles on the natural course of cervical precursor lesions. Methods We followed a total of 454 Japanese women with cytological low-grade squamous intraepithelial lesion (LSIL) and histological cervical intraepithelial neoplasia grades 1 to 2 (CIN1-CIN2). Patients were tested for HLA class II alleles and cervical human papillomavirus DNA at the time of entry and then monitored by cytology and colposcopy every 4 months for a mean follow-up of 39.0 months. We analyzed cumulative probabilities of cytological regression to at least 2 consecutive negative Papanicolaou tests and histological progression to biopsy-positive CIN3. Results During the follow-up period, 39 lesions progressed to CIN3, and 282 lesions regressed to normal cytology. Progression to CIN3 did not occur in DRB1*1302-positive women, and this protective effect of DRB1*1302 was statistically significant (P = 0.03). Low-grade squamous intraepithelial lesion regressed to normal cytology more quickly in DRB1*1302-positive women than in DRB1*1302-negative women (median time, 8.9 months vs 14.2 months), although the difference was not statistically significant (P = 0.16). The risk of LSIL persistence or progression to CIN3 within 5 years was not affected by any other HLA class II alleles. Conclusion By using a prospective study design, we demonstrated the protective effect of the DRB1*1302 allele against progression to CIN3 among Japanese women with LSIL.

Potential impact of combined high‐ and low‐risk human papillomavirus infection on the progression of cervical intraepithelial neoplasia 2

Few studies have examined the effect of combined low‐risk human papillomavirus (LR‐HPV) and high‐risk human papillomavirus (HR‐HPV) infection on the progression of cervical intraepithelial neoplasia (CIN)2 to CIN3. This multi‐institutional prospective cohort study investigated the risk of progression of CIN2 with various combinations of HR‐HPV and LR‐HPV infection.