Very early cytological and DNA-cytometric diagnosis of in situ carcinoma in an immunosuppressed liver transplant recipient

Diagnostic accuracy of brush biopsy-based cytology for the early detection of oral cancer and precursors in Fanconi anemia

BACKGROUND

Individuals with Fanconi anemia (FA) have a 500-fold to 700-fold elevated risk, much earlier onset, and limited therapeutic options for oral squamous cell carcinoma (SCC) compared with the general population. The early detection of SCC, or preferably its precursors, is mandatory to retain curative therapeutic options. Due to frequent synchronic and metachronic oral lesions, tissue biopsies, as usually recommended by guidelines, often are not feasible. In the current study, an alternative strategy for early detection using oral brush biopsy-based cytology was validated regarding its diagnostic accuracy.

METHODS

Over a 12-year period, the oral cavities of a large cohort of 713 individuals with FA were inspected systematically and brush biopsy-based cytology of 1233 visible oral lesions was performed. In cases of inconclusive cytology, analysis of DNA ploidy was performed whenever possible. The results were correlated to a long-term clinicopathological follow-up reference standard.

RESULTS

A total of 737 lesions were suitable for statistical analysis, including 86 lesions with at least high-grade oral epithelial dysplasia in 30 patients. For cytology, the sensitivity and specificity were 97.7% and 84.5%, respectively. Additional analysis of DNA ploidy increased the sensitivity and specificity to 100% and 92.2%, respectively.

CONCLUSIONS

Careful inspection of the oral cavity of individuals with FA followed by brush biopsy-based cytology appears to identify visible oral, potentially malignant and malignant lesions that warrant treatment. Approximately 63% of SCC and precursor lesions are detected at a noninvasive or early stage. Negative cytology or a lack of DNA aneuploidy can exclude high-grade oral epithelial dysplasia or SCC with high accuracy and thus reduce the need for invasive diagnostic biopsies.

Quantitative prediction of oral cancer risk in patients with oral leukoplakia

Exfoliative cytology has been widely used for early diagnosis of oral squamous cell carcinoma. We have developed an oral cancer risk index using DNA index value to quantitatively assess cancer risk in patients with oral leukoplakia, but with limited success. In order to improve the performance of the risk index, we collected exfoliative cytology, histopathology, and clinical follow-up data from two independent cohorts of normal, leukoplakia and cancer subjects (training set and validation set). Peaks were defined on the basis of first derivatives with positives, and modern machine learning techniques were utilized to build statistical prediction models on the reconstructed data. Random forest was found to be the best model with high sensitivity (100%) and specificity (99.2%). Using the Peaks-Random Forest model, we constructed an index (OCRI2) as a quantitative measurement of cancer risk. Among 11 leukoplakia patients with an OCRI2 over 0.5, 4 (36.4%) developed cancer during follow-up (23 ± 20 months), whereas 3 (5.3%) of 57 leukoplakia patients with an OCRI2 less than 0.5 developed cancer (32 ± 31 months). OCRI2 is better than other methods in predicting oral squamous cell carcinoma during follow-up. In conclusion, we have developed an exfoliative cytology-based method for quantitative prediction of cancer risk in patients with oral leukoplakia.

Oral Cancer and Oral Precancerous Lesions in Inflammatory Bowel Diseases: A Systematic Review

Oral cancer is historically linked to well-known behavioural risk factors such as tobacco smoking and alcohol consumption. Other risk factors include age over 40, male sex, several dietary factors, nutritional deficiencies, viruses, sexually transmitted infections, human papillomavirus, chronic irritation, and possibly genetic predisposition. Precancerous lesions in the oral cavity include leukoplakia, erythroplakia, and lichen planus. Histology of oral cancer varies widely but the great majority are squamous cell carcinomas.Epidemiological studies and cancer registries have shown a consistently increased risk of oral malignancies in kidney, bone marrow, heart, or liver transplantation, in graft vs host disease, and in patients with HIV infection. Because of the increasing use of immunosuppressive drugs in patients with inflammatory bowel disease, it is useful to more accurately delineate the consequences of chronic immunosuppression to the oral cavity. Oral cancer and precancerous oral lesions in patients with inflammatory bowel disease [IBD] have been scarcely reported and reviews on the topic are lacking.We conducted a literature search using the terms and variants of all cancerous and precancerous oral manifestations of inflammatory bowel diseases. By retrieving the existing literature, it is evident that patients with IBD belong to the high-risk group of developing these lesions, a phenomenon amplified by the increasing HPV prevalence. Education on modifiable risk behaviours in patients with oral cancer is the cornerstone of prevention.Oral screening should be performed for all IBD patients, especially those who are about to start an immunosuppressant or biological drug.

Quantitative risk stratification of oral leukoplakia with exfoliative cytology

Exfoliative cytology has been widely used for early diagnosis of oral squamous cell carcinoma (OSCC). Test outcome is reported as “negative”, “atypical” (defined as abnormal epithelial changes of uncertain diagnostic significance), and “positive” (defined as definitive cellular evidence of epithelial dysplasia or carcinoma). The major challenge is how to properly manage the “atypical” patients in order to diagnose OSCC early and prevent OSCC. In this study, we collected exfoliative cytology data, histopathology data, and clinical data of normal subjects (n=102), oral leukoplakia (OLK) patients (n=82), and OSCC patients (n=93), and developed a data analysis procedure for quantitative risk stratification of OLK patients. This procedure involving a step called expert-guided data transformation and reconstruction (EdTAR) which allows automatic data processing and reconstruction and reveals informative signals for subsequent risk stratification. Modern machine learning techniques were utilized to build statistical prediction models on the reconstructed data. Among the several models tested using resampling methods for parameter pruning and performance evaluation, Support Vector Machine (SVM) was found to be optimal with a high sensitivity (median>0.98) and specificity (median>0.99). With the SVM model, we constructed an oral cancer risk index (OCRI) which may potentially guide clinical follow-up of OLK patients. One OLK patient with an initial OCRI of 0.88 developed OSCC after 40 months of follow-up. In conclusion, we have developed a statistical method for qualitative risk stratification of OLK patients. This method may potentially improve cost-effectiveness of clinical follow-up of OLK patients, and help design clinical chemoprevention trial for high-risk populations.

The use of quantitative cytology in identifying high-risk oral lesions in community practice

OBJECTIVE

This study evaluated whether quantitative cytology (QC) can disclose abnormal DNA content (aneuploidy) and abnormal nuclear morphology of high-risk potentially malignant disorders (PMDs) of the oral mucosa found in the community in reference to clinicohistopathologic features.

STUDY DESIGN

A total of 171 patients at community-based clinic with suspicious oral lesions were evaluated with concurrent but independent histopathologic and QC assessments.

RESULTS

QC-positive results were associated with oral lesions with higher clinical risk factors: large size, nonhomogeneous surface texture, and located at high-risk anatomic sites. Only 3% of benign/reactive and 5% of low-risk PMDs were QC positive, while 92% of high-risk PMDs and 88% of squamous cell carcinomas (SCCs) were QC positive. The sensitivity and specificity of QC for detection of high-grade dysplasia/SCC were 89% and 97%.

CONCLUSIONS

QC could serve as an adjunctive tool for the detection of high-risk PMD/SCC requiring immediate clinical care.

[Performance of conventional oral brush biopsies]

BACKGROUND

This study evaluated the performance of oral brush biopsies using standard morphological analysis and haematoxylin and eosin (HE) staining for detecting oral squamous cell carcinomas and their respective precursor lesions

PATIENTS AND METHODS

Brush biopsies were obtained in 169 consecutive patients who underwent routine biopsies and histological examination for clinically suspicious oral lesions. Air-dried smears were processed by acetone fixation and HE staining. Cytological assessment used well-established criteria of atypia to classify the specimen as either "tumor negative" (no signs of atypia, no malignant cells) or "tumor positive" (malignant cells, any sign of atypia or doubtful cells).

RESULTS

Despite a sufficient number of cells, a definite cytological diagnosis could not be established in six cases. According to the criteria specified above, these specimens were classified as "tumor positive." The cytological analysis identified 49 out of 62 oral malignancies (sensitivity 79%). Seven out of 107 benign lesions were classified as false positive (specificity 93%). The positive and negative predictive values were each 88%.

CONCLUSION

Oral brush biopsies will identify only about 80% of oral malignancies when the smears are processed by routine HE stains and are analysed via standard morphological criteria. Thus, this technique should not be used for diagnostic proof or to exclude malignant cells in a lesion suspicious for cancer. However, oral brush biopsy provides a versatile back-up strategy to uncover the true nature of the disease if a lesion is clinically considered benign by mistake.

Verrucous carcinoma of the buccal mucosa: histopathological, cytological and DNA-cytometric features

We describe a patient with an exophytic oral lesion diagnosed as verrucous carcinoma. The lesion existed without metastases, at least 5 years. Local excisions led to recurrences and continuous expansion. Scalpel biopsies for histopathological and polymerase chain reaction examination were obtained from characteristic regions of the lesion. Brush biopsies for exfoliative cytology (EC) were taken, in order to screen the mucosal area covered by the lesion. After Feulgen restaining of the smears, nuclear DNA contents were measured using a TV image analysis system. An exophytic lesion of the buccal mucosa was diagnosed as low-grade malignant through histopathology and EC combined with DNA-image cytometry (peritetraploid DNA-aneuploidy). Due to almost normal microscopic appearance of the epithelium of verrucous carcinoma, thorough cytological/DNA-cytometric and histological examinations are needed. Brush biopsies of such neoplastic oral lesions showing DNA-aneuploidy with peritetraploid stemlines should be used for diagnosis and follow-up examination of these patients.

[Oral cytology: historical development, current status, and perspectives]

Oral cytology has aroused new interest caused by introduction of the cytobrush as a sampling device and the use of additional analytical methods. By brushing it is possible to reach deeper layers of the oral mucosa where squamous intraepithelial neoplasia (SIN) begins. The biological potential of the oral epithelial cells obtained can be evaluated by the following additional methods: computer-assisted image analysis (OralCDx), DNA cytometry, immunohistochemistry, monolayer cytology, and molecular biological analysis. All of those methods can increase sensitivity (up to 100%) and specificity (up to 100%) of oral brush biopsy. Nevertheless, there are reports that oral epithelial carcinomas were not identified. No comparative study exists allowing conclusions to be drawn about the value of the single methods. Immunocytochemistry with commercial antibodies against laminin-5 is generally available and methodologically easy. Oral brush biopsy as a non invasive diagnostic method can be useful for the early detection of oral mucosal lesions. Positive findings or progression of the lesion despite negative findings are indications to refer the patient to a specialized clinic where a surgical biopsy should be performed, followed by histopathological analysis. Histopathology remains the gold standard for the definitive diagnosis of oral malignant lesions.

High-molecular tenascin-C as an indicator of atypical cells in oral brush biopsies

Tumour-invasion like wound healing is characterised by the formation of an extracellular matrix with a high tenascin-C content. The tenascin-C molecule undergoes alternative splicing. Analysis using antibody BC2 indicates that especially the high-molecular tenascin-C (hm tn-C) variants are typically tumour-associated, while distribution in normal tissue is restrictive. This study investigated whether hm tn-C is a suitable indicator of atypical cells with invasive potential in oral brush biopsies. One hundred fifty nine consecutive oral brush biopsies with histopathological diagnoses were analysed for the identification of atypical cells. A standardised haematoxylin and eosin staining plus standardised immunocytochemistry using the monoclonal anti-hm tn-C antibody was performed. The bound hm tn-C antibodies were detected with the streptavidine/alkaline phosphatase technique in the autostainer. Conventional cytology produced four false-positives when identifying atypical cells in brush biopsies of inflammatory/benign hyperproliferative mucosa (specificity 96%), while 10 in 52 carcinomas and three of eight recurrences were not identified (sensitivity 78%). Ten of these 13 non-identified tumours could be marked when adding the hm tn-C assay (increasing specificity to 99%). Combining the two assays also reduced the false-positive outcomes from four to one (increasing sensitivity to 95%). The positive and negative predictive values were 92 and 88% for conventional cytology vs 98 and 97% for the dual assay. (1) A 95%-sensitivity proves hm tn-C assisted conventional cytology to be a suitable means of identifying atypical cells in oral brush biopsies. (2) The positive (98%) and negative (97%) predictive values obtained approximate hm tn-C assisted conventional cytology to laminin-5 (100/97%).

Cytologic and DNA-cytometric examination of oral lesions in lichen planus

BACKGROUND

The aim of the present study was to evaluate the diagnostic value of exfoliative cytology (EC) and DNA image cytometry applied to oral lesions of lichen planus (LP; n = 56), in order to detect or exclude malignant transformation.

METHODS

Brush and excisional biopsies were obtained from 56 patients. In cases of oral LP in which brush biopsies were suspicious for tumor cells, nuclear DNA contents were measured, using a TV Image Analysis System.

RESULTS

In 50 patients EC yielded tumor cell-negative, doubtful in four cases and suspicious results obtained in two cases. DNA image cytometry revealed DNA-aneuploidy only in the two suspicious cases. The comparison between cytologic/DNA-cytometric diagnosis and biopsy histology resulted in a total agreement (LP without dysplasia: 54 and squamous cell carcinoma in LP: two cases).

CONCLUSIONS

In conclusion, cytology with DNA-cytometry is a highly sensitive, specific, and non-invasive method, which can be used for periodical follow up of oral LP lesions in order to early detect or exclude malignancy.