T3N0 glottic carcinoma: DNA S-phase as a predictor of the outcome after radiotherapy

Prognostic relevance of cell proliferation in head and neck tumors

Cell proliferative activity has been extensively investigated in head and neck tumors. Ki67/MIB-1 immunostaining, tritiated thymidine or bromodeoxyuridine labeling indices, DNA S-phase fraction, proliferating cell nuclear antigen expression, potential doubling time and analysis of the nucleolar organizer region associated proteins (AgNORs) have shown significant correlation with prognosis in 4806 cases of tumors of the oral cavity, salivary glands, pharynx and larynx. However, this was not observed in 2968 other reported cases. Discrepancies may depend on various factors: the heterogeneity of the series, which include tumors from various anatomic sites and patients treated with different therapy, and the lack of standardization of methods for assessing cell proliferation. Furthermore, none of the methods currently applied can by themselves define the actual proliferative activity, as it depends both on the proportion of cells committed to the cycle (growth fraction) and the speed of the cell cycle. Indeed, the actual proliferative activity of a tumor could well be measured by the equation [PA = Ki67 or MIB-1 scores x AgNORs], as we did in pharyngeal carcinoma. Provided that large and homogeneous series are evaluated by standardized methods, cell proliferative activity can still be regarded as an inexpensive and reliable prognostic factor in head and neck tumors.

Cell proliferation activity and kinetic profile in the prognosis and therapeutic management of carcinoma of the pharynx and larynx

Prognosis and management of carcinoma of the pharynx and larynx is now based on the morphologic analysis of the tumor spreading, differentiation grading, and type of microscopic invasion. The DNA ploidy status and the cell proliferation activity analyzed by flow cytometry give us complementary information about the prognosis and the management and support of the patients. We performed a study of 91 cases of carcinoma of the larynx and pharynx by means of flow cytometry. Forty-three patients were treated by surgery alone, and 48 patients also received radiotherapy. Fifty-five were aneuploid (60%); this percentage increased to 74% in the pharynx area and fell to 47% at the larynx level. The aneuploid tumors showed worse behavior in the patients treated by surgery alone compared with those who also received radiotherapy. The S-phase fraction was high in aneuploid tumors, in positive lymph nodes, and in advanced stages. The S-phase fraction was higher in poorly differentiated tumors. In patients treated by surgery alone, we noticed that by combining both cytometric variables two different kinetic profiles could be defined related to the patients' behavior. The diploid tumors with a low S phase had the greatest rates of survival, whereas diploid tumors with a high rate of S phase and aneuploids had a lower rate.

Prognostic factors in carcinoma of the larynx: relevance of DNA ploidy, S-fractions and localization of the tumour

The influence of the cell cycle profile and the site of the primary tumour on the overall survival were examined in 36 patients with squamous cell carcinoma of the larynx. DNA ploidy (p = 0.0091), the overall proliferative activity (p = 0.0001), the overall proliferative activity of diploid tumour cells (p = 0.0017) and primary tumour site (p = 0.0008) were found to be significant single prognostic factors of the overall survival. Multivariate analysis showed that only the overall proliferative activity was prognostically significant (p = 0.013). The results of the study show that the supraglottic site of the tumours correlates significantly with DNA ploidy (p = 0.0334) and the overall proliferative activity of tumour cells (p = 0.0159), whereas the correlation with proliferative activity of diploid tumour cells (p = 0.1416) has not been confirmed by this study. Glottic tumours showed a prognostically significant correlation with the overall proliferative activity (p = 0.0037) and proliferative activity of diploid tumour (p = 0.0054). Such a prognostic correlation was not found for DNA ploidy (p = 0.6542).

Oestrogen increases S-phase fraction and oestrogen and progesterone receptors in human cervical cancer in vivo

Although cancer of the cervix is traditionally considered not to be responsive to steroid hormones, an in vitro study has reported that the addition of oestrogen increased cellular proliferation in a cervix cancer cell line that was inhibited by progesterone. We investigated whether the reported in vitro effects of oestrogen and progesterone on cellular proliferation can be replicated in locally advanced cervical cancer in vivo and whether these effects, if any, are related to oestrogen and progesterone receptor (ER and PgR) content of the tumour. One hundred post-menopausal patients with locally advanced cervical cancer were systematically allocated by rotation to the four treatment groups: (1) control group receiving no treatment; (2) ethinyl oestradiol 50 micrograms: (3) norethisterone 5 mg: (4) a combination of ethinyl oestradiol and norethisterone. Hormone treatment (five doses) was given orally every 12 h. Tissue biopsies were taken before and 12 h after the last hormone treatment. S-phase fraction (SpF) was measured by flow cytometry, and ER and PgR were measured by enzyme immunoassay. Results were analysed using two-factor analysis of variance, the factors being oestrogen-absent or present- and progesterone-absent or present. The main effects of oestrogen were increases in SpF, ER and PgR, which were statistically significant (P = 0.0056, 0.0009 and 0.01 respectively), indicating that there is much greater change in these three parameters in the presence of oestrogen (mean changes 7.808%, 6.258 fmol mg-1 and 12.716 fmol mg-1 for SpF, ER and PgR respectively) than in its absence (mean change -1.986%,-3.041 fmol mg-1 and 1.736 fmol mg-1 respectively). The progestogen main effect and the oestrogen-progestogen interaction were not significant. The rise in SpF, ER and PgR in the presence of oestrogen had a correlation coefficient with the initial ER values of -0.0565, -0.2863 and -0.1230 respectively, none being statistically significant, suggesting that the oestrogen actions were not strictly related to baseline ER concentrations. The combined median baseline ER and PgR values of the four groups were 1.48 fmol mg-1 and 0.80 fmol mg-1 respectively. Our results show that oestrogen is capable of increasing SpF in locally advanced cervical cancer in vivo and may help to revive interest in the use of oestrogen as a radiosensitizing agent in the treatment of this disease.

Head and neck cancer

This synthesis of the literature on radiotherapy for head and neck cancer is based on 424 scientific articles, including 3 meta-analyses, 38 randomized studies, 45 prospective studies, and 246 retrospective studies. These studies involve 79174 patients. The literature review shows that radiotherapy, either alone or in combination with surgery, plays an essential role in treating head and neck cancers. When tumors are localized, many tumor patients can be cured by radiotherapy alone and thereby maintain full organ function (1, 2). Current technical advancements in radiotherapy offer the potential for better local tumor control with lower morbidity (3). This, however, will require more sophisticated dose planning resources. To further improve treatment results for advanced tumors, other fractionation schedules, mainly hyperfractionation, should be introduced (5). This mainly increases the demands on staff resources for radiotherapy. The combination of radiotherapy and chemotherapy should be subjected to further controlled studies involving a sufficiently large number of patients (4, 5). Interstitial treatment (in the hands of experienced radiotherapists) yields good results for selected cancers. The method should be more generally accessible in Sweden. Intraoperative radiotherapy should be targeted for further study and development.

Flow cytometric DNA analysis and lysosomal cathepsins B and L in locally advanced laryngeal cancer. Relationship with clinicopathologic parameters and prognostic significance

BACKGROUND

The traditional factors of locally advanced laryngeal squamous cell carcinoma (LSCC) have limited predictive value for the identification of high risk patients. Therefore, it is extremely important to define prognostic factors that identify the more aggressive types. Reliable and reproducible prognostic indicators are being investigated to help clinicians identify high risk groups and address more rational treatment.

METHODS

Flow cytometric DNA ploidy and S-phase fraction (SPF) measurements were performed on frozen tumor tissues from a consecutive series of 71 patients with Stage III and IV LSCC: Lysosomal cathepsin B and L activity levels were determined biochemically in matched paired sets of tumor tissue and normal mucosa samples.

RESULTS

By univariate analysis, lymph node positivity, poor histologic differentiation, DNA aneuploidy, high SPF, and high tumor/mucosa ratio of cathepsin B activity were significantly related to risk of relapse, whereas only DNA aneuploidy and high SPF proved to be significantly related to risk of death. Multivariate analysis showed that high histologic grade and high SPF values (> 15.1%) were independent prognostic factors related to risk of relapse (relative risk [RR] = 3.54; 95% confidence limits [CL] = 1.05-12.0; and RR = 4.22; CL = 1.54-11.6, respectively), whereas only high SPF was related to risk of death (RR = 3.63; CL = 1.17-11.3).

CONCLUSIONS

S-phase fraction is an independent predictor of relapse free and overall survival in patients with locally advanced LSCC. On the basis of these findings, SPF should be used in addition to other established prognostic factors to refine the prognostic assessment of these patients further. More studies are needed for a better evaluation of the prognostic significance of DNA ploidy and that of lysosomal cysteine proteinases in these tumors.