Flow cytometric analysis of DNA content in squamous carcinoma of the tongue: the relationship to host and tumour factors and survival

Correlation Between Histological Grading and Ploidy Status in Oral Leukoplakia, Oral Submucous Fibrosis, and Oral Squamous Cell Carcinoma: A Flow Cytometric Analysis

Background:

Methods to analyze progression of carcinogenesis and stage of cancer are vital nowadays due to the high prevalence of these lesions. DNA ploidy analysis is one such important method in early diagnosis and improving prognosis.

Aims and Objectives:

The aim of this study was to correlate histopathological grading and DNA ploidy in oral leukoplakia, oral submucous fibrosis (OSMF), and oral squamous cell carcinoma (OSCC) cases.

Materials and Methods:

Our study included 80 subjects, grouped into 4 groups of 20 each of OSCC, leukoplakia, OSMF, and healthy individuals. Histopathological grading was carried out in study cases, DNA ploidy was estimated using flow cytometry, and both the findings were correlated.

Results:

Among the 20 cases of leukoplakia group, 6 cases showed aneuploidy and 14 showed diploidy. In the 20 cases of OSF group, 2 cases showed aneuploidy and 18 showed diploidy, and in the 20 cases of OSCC group, 10 showed aneuploidy and 10 showed diploidy. Most of the aneuploidy cases showed severe dysplasia.

Conclusion:

Analysis of DNA ploidy status can serve as a diagnostic tool for early detection of malignancies owing to the subjective nature of traditional histopathological grading.

DNA ploidy status as a prognostic marker and predictor of lymph node metastasis in laryngeal carcinoma

In patients with laryngeal carcinoma, nodal metastasis, recurrence after radiotherapy, and prognosis are important factors in clinical decision-making. Parameters such as tumor stage are considered insufficient for predicting these important items. The DNA ploidy status of the tumor may be a useful additional marker. The DNA ploidy status of 38 laryngeal cancers was determined by flow cytometry. Correlations were studied with TNM stage, differentiation, survival rate, relapse risk, recurrence after radiotherapy, and nodal metastasis. A positive correlation of DNA ploidy status with the development of lymph node metastases was found for diploid and peridiploid versus aneuploid tumors (DNA index, <1.4 versus > or = 1.4; p = .007). No correlation was found between ploidy status and recurrence after radiotherapy. The overall survival rate (p = .01), but not the disease-specific survival rate or the relapse risk, showed a correlation with the ploidy status. The DNA ploidy status may be a useful marker for metastatic behavior in head and neck squamous cell carcinoma and may therefore be helpful in decision-making concerning elective treatment of the neck.

Can flow cytometrically determined DNA ploidy and S-phase fraction predict regional metastasis in squamous cell carcinoma of the oral cavity?

BACKGROUND

The value of flow cytometric analysis of DNA ploidy and S-phase fraction (SPF) as an indicator of regional metastasis in oral cancer is currently being debated. Intratumoral heterogeneity makes this problem complex.

METHODS

Intratumoral DNA ploidy heterogeneity and intratumoral SPF variation were examined using multiple specimens from 31 surgically resected specimens taken from patients with oral cancer without preoperative therapy. Flow cytometric analysis of single biopsy specimens from 79 patients with oral cancer was also undertaken to ascertain their value as indicators of regional metastasis.

RESULTS

Forty-five percent (14 of 31) of tumors showed intratumoral ploidy heterogeneity. Intratumoral SPF variation in the 31 tumors ranged from 0.2% to 6.9% (mean, 3.3%). Multivariate analysis showed that a SPF greater than 27% was the most important parameter for predicting regional metastasis.

CONCLUSIONS

DNA ploidy is heterogeneous within a tumor, whereas SPF is relatively stable and can be correlated with regional metastasis in oral cancer.

Squamous carcinoma of the tongue: review

Carcinoma of the tongue is a common condition treated by oral and maxillofacial surgeons. The tongue is a complex anatomical site at the entrance of the oropharynx, bounded by the floor of mouth and lingual mandibular cortex; its form and mobility are crucial for efficient swallowing; speech, and the appreciation of taste. Single and multiple treatments have been used, but the tongue remains a difficult area to assess and treat. In this paper, we have attempted to review some of the papers published over the last 20 years with particular reference to prognosis and functional outcome. We have dealt exclusively with squamous cell carcinoma of the tongue and its management by surgery, radiotherapy, brachytherapy, photodynamic therapy, and chemotherapy.

The significance of DNA flow cytometry in predicting survival and delayed clinical manifestation of occult lymph node metastasis to the untreated neck in patients with oral squamous cell carcinoma

A total number of 116 clinically neck-negative patients with squamous cell carcinoma of the oral cavity who underwent radical primary tumour surgery without simultaneous neck treatment were entered into this prospective study. The 5 year overall survival rate was 87% for patients with flow cytometrically diploid tumours and 58% for the aneuploid group (P < 0.05). By multivariate survival analysis, tumour stage (P < 0.05) and DNA ploidy (P < 0.05) were significantly associated with the outcome. The cumulative 3 year rate of delayed clinical manifestation of lymph node metastasis to the previously untreated neck was 12.6% for patients with flow cytometrically diploid tumours and 41.3% for the aneuploid group (P < 0.01). By multivariate analysis, the DNA ploidy status of the primary tumour was the only factor among tumour stage, localization and degree of histological differentiation predictive of occult metastasis development (P < 0.05). Also, patients with T1 tumours who frequently are not considered to benefit from elective neck dissection were at high risk of subclinical lymph node involvement if the primary tumours were aneuploid (47%), whereas only 10% of the diploid T1 sample showed occult neck disease. Particularly in patients with less extensive oral carcinomas, DNA aneuploidy is therefore an important decisive factor in elective neck dissection.

Nuclear DNA content and p53 overexpression in stage I squamous cell carcinoma of the tongue compared with advanced tongue carcinomas

AIMS

To evaluate the predictive value of the nuclear DNA content (image cytometry) and p53 overexpression (immuno-histochemistry using antibody CM-1) in uniformly treated stage I carcinomas of the mobile tongue. Also, to compare stage I carcinomas with advanced tongue carcinomas (stages II-IV).

METHODS

Archival formalin fixed, paraffin wax embedded tumour specimens from 54 patients with stage I squamous cell carcinoma and 37 patients with advanced squamous cell carcinoma were analysed. Mean follow up time of the stage I carcinomas was 71 months (median, 62.5; range, 6-175).

RESULTS

Twenty three patients (stage I) had recurring disease: 10 had local recurrence (in the tongue) and 13 had regional recurrence (cervical metastases). Locally recurring stage I carcinomas had a more pronounced DNA deviation than the other stage I carcinomas and this degree of deviation was comparable with the DNA content of advanced carcinomas. Stage I carcinomas that developed regional recurrences overexpressed p53 more frequently. In Cox multivariate regression analysis of time to recurrence, DNA deviation was a significant parameter in tumours that recurred locally (p = 0.032). p53 overexpression was the only parameter close to significance for regional recurrence (p = 0.065).

CONCLUSIONS

Nuclear DNA content and p53 immunostaining are of value for the prediction of recurrence of stage I squamous cell carcinomas of the mobile tongue. Stage I tongue carcinomas that are prone to local recurrence show the same DNA content as do advanced tongue carcinomas.

Nodal metastases: predictive factors

Squamous cell carcinoma of the upper respiratory and digestive tract has a high risk for neck metastasis, which reduces the probability of regional control and survival. We analyzed the literature and our own experience to review the possible risk factors for the occurrence of metastasis. The most significant risk factors were: tumor site and size, grade of histologic differentiation, tumor thickness (tongue and floor of mouth carcinoma), vascular embolization, and perineural infiltration. A series of biomarkers has been studied over the last 10 years, but no one has proved to be significant enough for clinical use. Based on several multivariate analysis, it is recommended elective treatment of the neck for high-risk patients.

Can we detect or predict the presence of occult nodal metastases in patients with squamous carcinoma of the oral tongue?

BACKGROUND

When to do a neck dissection as part of the surgical treatment for a patient with squamous carcinoma of the oral tongue is controversial, particularly when the primary can be resected without entering the neck. If the patient who is at high risk for having occult nodal disease in the neck can be identified, node dissection with the glossectomy could be justified. To better identify patients for this procedure, we correlated various tumor and patient factors along with preoperative diagnostic studies with the presence or absence of pathologically positive nodes in a group of patients who underwent node dissection.

METHODS

Ninety-one previously untreated patients with biopsy-proved squamous carcinoma of the oral tongue were prospectively studied. All patients had a glossectomy and neck dissection as their initial treatment. The pathology findings (ie, lymph nodes with squamous cancer) were correlated with many preoperative and intraoperative factors, and a statistical analysis was made.

RESULTS

The use of computed tomography and ultrasound was not better than the clinical examination in determining the presence or absence of nodal metastases. The best predictors were depth of muscle invasion, double DNA aneuploidy, and histologic differentiation of the tumor.

CONCLUSIONS

All patients with stage T2-T4 squamous cancers of the oral tongue should have an elective dissection of the neck. Patients with T1N0 cancer who have a double DNA-aneuploid tumor, depth of muscle invasion > 4 mm, or have a poorly differentiated cancer should definitely undergo elective neck dissection. Ultrasound and computed tomography are of little value in predicting which patients have positive nodes.