Flow cytometric analysis of posterior oropharyngeal tumors

DNA analysis of squamous cell carcinoma in the oral cavity by image cytometry and its rating in the assessment of tumor prognosis

Image cytometric measurements on the DNA content of squamous cell carcinoma of the oral cavity were carried out to evaluate its relationship with clinicopathological features. In the prospective study 52 patients with operable oral cavity carcinoma in stage T1-4 and N0-3 were studied. The tumors were classified according to the TNM classification (UICC 1987) and graded histopathologically. A positive correlation between tumor size and ploidy status was observed. There was a significant correlation between ploidy status and histologically confirmed cervical lymph node metastases (P < 0.03). A relationship between histopathological grading and ploidy status was not found. The cumulative 5-year survival rate was significantly higher (P < 0.03) among patients with diploid DNA findings than among those with nondiploid findings. When assessing the prognosis of squamous cell carcinoma, DNA cytometry analysis should be used as an additional method. Particularly the primarily existing, significantly higher N stage, a higher frequency of metastases, and a significantly lower survival rate with nondiploid tumors underline the importance of this examination method.

The relation of radiosensitivity of hypopharyngeal squamous cell carcinoma to DNA ploidy

PURPOSE

The purpose of this study was to examine the radiosensitivity of T1, N0, M0 squamous cell carcinomas of the hypopharynx treated solely with external beam radiation.

MATERIALS AND METHODS

Nuclear DNA content and cell cycle kinetics of 29 archival paraffin-embedded specimens suitable for interpretation were analyzed with an ELITE flow cytometer (Coulter Diagnostics, Opa Locka, FL).

RESULTS

In the radiosensitive group with no evidence of disease for 36 months, 86% of the tumors were diploid and 14% were aneuploid. The mean DNA index for this group was 1.02. In the radioresistant group, with recurrence within 36 months, 80% of the tumors were aneuploid, and 20% were diploid. The mean DNA index for this group was 1.32.

CONCLUSIONS

The findings could have clinical significance because if aneuploidy occurs in an early hypopharyngeal squamous cell carcinoma, the clinician might select surgical resection over radiation therapy.