Ploidy and Proliferation Evaluated by Flow Cytometry. An Overview of Techniques and Impact in Oncology

Distinctive chromosomal instability patterns in oral verrucous and squamous cell carcinomas detected by high-resolution DNA flow cytometry

BACKGROUND

Oral verrucous carcinomas (OVCs) are characterized by better prognosis than oral squamous cell carcinomas (OSCCs). Because chromosomal instability (CIN) in solid tumors is indicative of prognosis, this study investigated whether OVCs and OSCCs were characterized by differences in CIN biomarkers.

METHODS

Fresh or frozen multiple tissue samples were submitted to high-resolution DNA flow cytometry (hr DNA-FCM).

RESULTS

DNA aneuploid sublines were detected in 6 of 9 OVCs (66.7%) and in 20 of 25 OSCCs (80.0%). Multiple DNA aneuploid sublines were observed, respectively, in 2 of 6 (33.3%) DNA aneuploid OVCs and in 14 of 20 (70%) DNA aneuploid OSCCs (P = .163). OVCs were mainly characterized by DNA Index (DI) values in the near-diploid region (DI≠1 and DI < 1.4), whereas aneuploid OSCCs carried most frequently multiple aneuploid sublines with high DI values (DI ≥ 1.4). DNA near-diploid and high aneuploid sublines were, respectively, 87.5% and 12.5% for the OVCs versus 30% and 70% for the OSCCs (P = .004).

CONCLUSIONS

Present data suggest that OVCs are characterized by a lower degree of CIN and tumor heterogeneity than OSCCs, such that they appear as "frozen" in an early stage of DNA near-diploid aneuploidy, as previously observed for oral preneoplastic lesions. These DI characteristics, which can easily be obtained by hr DNA-FCM, appear to reflect the well-known differences in aggressiveness and prognosis of OVCs and OSCCs.

Neuroblastoma in adolescents

BACKGROUND

Neuroblastoma (NB) occurs rarely during adolescence, and information is scarce on its characteristics and clinical course in this age group.

METHODS

Patients with NB who were included in the Italian Neuroblastoma Registry were considered for the current study. The clinical characteristics and survival of adolescents (age at diagnosis between 10 yrs and 18 yrs) were compared with those of children (ages 1-9 yrs). Infants (age < 1 yr) were excluded because of their well known favorable clinical course.

RESULTS

Between 1116 children and 53 adolescents who were evaluated, no differences were documented with regard to the primary tumor site and the prevalence of advanced stage at diagnosis. If only patients with Stage IV NB were considered, then adolescents were less likely to be diagnosed with bone/bone marrow metastases (77%) compared with children (94%; P = 0.038), but adolescents were more likely to have metastases at unusual sites, such as the lung parenchyma or the central nervous system (23% vs. 7%, respectively; P = 0.005). With regard to biologic characteristics, adolescents did not differ significantly from children, although they always had a lower prevalence of unfavorable markers. In particular, MYCN amplification was documented in 21% of children and in 11% of adolescents (P = 0.173). At age 10 years, adolescents had a 20% overall survival rate and a 22% event-free survival rate. Adolescents who had resectable disease had a 73% overall survival rate, which was worse compared with the rate among children with the same disease stage (89%), although the difference did not reach statistical significance (P = 0.159). No differences in survival were observed among patients with Stage IV NB, and adolescents had a probability of survival almost identical to that among children (6% vs. 16%, respectively; P = 0.481). However, when the analysis was restricted to events that occurred after patients developed a recurrence, even if the final outcome was poor for both groups, the difference was statistically significant (P = 0.022) mostly because of the more indolent disease course observed among the adolescents. This effect was even more evident for patients with Stage IV NB. When the 6-year cut-off point was used to separate children from adolescents, a significantly worse overall survival rate (P = 0.036) was documented for adolescents who had resectable disease (81% vs. 93% in children).

CONCLUSIONS

NB in adolescents had clinical and biologic characteristics similar to those observed among children. The clinical course of NB probably is correlated significantly with age at diagnosis, but information is scarce on the role of the biologic risk factors in this age group. The authors were able to identify a group of patients with a cut-off age between 6 years and 10 years that had a more indolent course but a worse prognosis.

Il valore predittivo della citometria a flusso nei carcinomi superficiall della vescica di basso grado

Flow cytometry (FCM) enables ploidy and proliferative tissue activity (PHASE S) to be quickly and objectively measured. This method is of predictive value regarding the biological behaviour of bladder tumours. The authors used FCM in a 5-year-follow-up study of 75 patients with papillary bladder carcinoma, who underwent therapeutic or staging transurethral resection in 1989. Results show a strict correlation between stage-ploidy-Progression as well as the significance of S-PHASE cells in relation to low-grade diploid tumours.

Potential doubling time in head and neck tumors treated by primary radiotherapy: preliminary evidence for a prognostic significance in local control

PURPOSE

The aim of the study was to determine preliminarily whether cell kinetic parameters evaluated using in vivo infusion of bromodeoxyuridine (BrdUrd) and flow cytometry, play a role as prognostic factors of loco-regional control in squamous cell head and neck carcinoma treated with radiotherapy.

METHODS AND MATERIALS

Between April 1989 and December 1991, 42 patients with unresectable Stage II-IV squamous cell carcinoma of the oral cavity, pharynx or larynx were given an infusion of BrdUrd solution prior to primary tumor biopsy sampling at 4-6 hr later. The simultaneous labeling S-phase fraction (LI) and duration (Ts) as well as the estimated potential doubling time (Tpot) were measured using flow cytometric analysis of BrdUrd and DNA content. Twenty-six patients received standard radiotherapy (70 Gy/35 fractions/7 weeks) whereas 15 patients were treated with the concomitant boost technique (75 Gy/40 fractions/6 weeks).

RESULTS

A complete set of flow cytometric data was available for 31 patients. The median value of LI, Ts, and Tpot were 9%, 9 hr and 5 days, respectively. Univariate analysis among the patients treated homogeneously by standard radiotherapy, indicated that local control was affected by Tpot value (p = 0.02). When the same analysis was performed for the patients treated with either standard radiotherapy or concomitant boost regimen, we found a p = 0.04. Thus, patients with a tumor Tpot value < or = 5 days had a significantly lower three-year local control than patients with Tpot > 5 days. Log-rank test univariate analysis showed, in addition, that nodal status was the strongest prognostic factor of local control (p = 0.005). Age, tumor stage, tumor site, performance status, grading, radiotherapy regimen, DNA ploidy and LI value were, instead, not significantly related to loco-regional control. Finally, when comparing the type of radiotherapy for tumors with Tpot < or = 5 days, we found a trend toward a better local control after concomitant boost regimen, with respect to standard regimen (p = 0.06).

CONCLUSION

The present preliminary results suggest that Tpot could play a role as additional prognostic factor influencing the disease outcome in head and neck carcinoma treated by radiotherapy.

DNA aneuploidy is an independent factor of poor prognosis in pancreatic and peripancreatic cancer

The purpose of this study was to investigate the clinical significance of DNA ploidy, as assessed by flow cytometry, for pancreatic and peripancreatic cancers. Between 1988 and 1990, we examined fresh/frozen samples from 49 patients who had histologically confirmed adenocarcinomas of the bilio-pancreatic carrefour: They had 23 cancers of the pancreas, 21 of the Vater's papilla, and 5 of the common bile duct. All patients were selected among a cohort of subjects who underwent Endoscopic Retrograde Cholangio Pancreatography (ERCP) and/or surgery. No prognostic impact of age, sex, stage, and surgical treatment on survival was observed by univariate analysis. When the affected organ was considered, a statistically significant difference in survival was observed: At 88 wk, survival was 0% for pancreatic and common bile duct cancer patients, and 18.2% at 175 wk for Vater's papilla cancer patients (p = 0.04). In addition, we found, irrespective of affected organ, that the patients with DNA diploid tumors had a statistically significant survival advantage as compared to those with DNA aneuploidy (p = 0.02). Furthermore, the statistically significant prognostic power of DNA ploidy was confirmed when patients with tumors of the pancreas and those with tumors of the Vater's papilla were separately analyzed.(ABSTRACT TRUNCATED AT 250 WORDS)

Dna Flow Cytometry in Bladder Tumours: New Perspectives

An International “DNA Cytometry Consensus Conference” was held in October 1992, in Maine (USA): The Author reports the opinions concerning bladder tumours, expressed by the experts at the Conference. Models for future studies with Flow Cytometry are also reported.

Activity of 4-HPR in superficial bladder cancer using DNA flow cytometry as an intermediate endpoint

The ability of the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4-HPR) to affect the outcome of previously resected superficial bladder cancer was investigated in a pilot study using DNA content flow cytometry and conventional cytology as intermediate endpoints. Twelve patients were treated with oral 4-HPR (200 mg daily) and compared with 17 non-randomized, untreated controls. The median interval between transurethral resection and 4-HPR administration was 5.5 months (range 0-36). The median follow-up period was 12 months (range 3-31) in the 4-HPR group and 9 months (range 2-22) in the control group. The proportion of patients with DNA aneuploid stemlines in bladder-washed cells decreased from 7/12 (58%) to 5/11 (45%) in the 4-HPR group, but increased from 7/17 (41%) to 10/17 (59%) in the control group. In patients with stable diploid profiles, mean (+/- SE) S-phase and G2+M-phase fractions decreased in the course of retinoid treatment from basal levels of 15.2 +/- 4.1% to 7.5 +/- 3.3% and 10.3 +/- 2.2% to 5.2 +/- 0.4%, respectively. The same parameters in the control group changed from basal levels of 14.6 +/- 3.4% to 12.4 +/- 2.7% and 9.8 +/- 1.6% to 12.6 +/- 1.6%, respectively. Positive or suspicious cytologic examinations were present in 3/12 (25%) treated cases prior to 4-HPR administration and all subsequently reverted to normal. The same parameter in the control group increased from 4/17 (24%) to 6/17 (35%) during follow-up. Impaired adaptation to darkness was recorded in 4 patients, and transient dermatologic alterations were observed in one-third of the patients, requiring dose reduction in one case.(ABSTRACT TRUNCATED AT 250 WORDS)