DNA image cytometry: a prognostic tool in rectal cancer?

Stage-specific frequency and prognostic significance of aneuploidy in patients with sporadic colorectal cancer--a meta-analysis and current overview

PURPOSE

Aneuploidy has long been suggested as an independent prognostic marker for colorectal cancer (CRC) patients and could thus aid for individualized medicine. However, due to a large spectrum of deviating studies, expert panels do not recommend ploidy assessment. In order to clarify a potential bias of stage-specific frequency of aneuploidy, we now conducted a meta-analysis combined with a systematic review regarding aneuploidy and prognosis.

METHODS

A systematic, web-based search process retrieved 1935 studies published in English between 1990 and 2011. The defined endpoint for the meta-analysis was an increase in aneuploidy frequency between early- (Dukes A, B and UICC I, II; n = 3632 samples) and late-stage (Dukes C, D and UICC III, IV; n = 3440 samples) colorectal carcinomas.

RESULTS

Of 1935 studies initially identified, 17 image (2130 patients) and 20 (7023 patients) flow cytometric studies were analyzed in detail. The meta-analysis (7072 patients) revealed late-stage CRC to be more frequently aneuploid than early-stage CRC (odds ratio 1.51, 95 % CI 1.37-1.67; p = 0.0007). Independent of tumor stage, the overall range of aneuploidy was 39 to 81 % (median 58 %), and altogether, 21 (54.1 %) studies described a significant prognostic impact of aneuploidy for overall, disease-specific, and recurrence-free survival, respectively.

CONCLUSIONS

A substantial number of studies showed a prognostic importance of aneuploidy in CRC. Furthermore, the higher frequency of aneuploidy in late-stage CRC implies an increase in genomic instability with CRC progression, indicating aneuploidy to be also a stage-specific prognostic marker.

Factors influencing survival after resection of pancreatic cancer. A DNA analysis and a histomorphologic study

BACKGROUND

The influence of DNA content on prognosis in stomach cancer has been investigated rarely, and the results are controversial.

METHOD

The prognostic relevance of the DNA content and histomorphologic parameters was evaluated in 41 patients after resection of pancreatic cancer.

RESULTS

In the univariate analysis, the DNA content, tumor size, lymph node status, tumor stage, nuclear grade, and type of resection had a statistically significant influence on the prognosis. No association was found between the DNA content and the histomorphologic features. Apart from the operative procedure, the DNA content was the strongest indicator of prognosis in the multivariate analysis.

CONCLUSIONS

Further investigations are necessary to find out if DNA analysis can be performed preoperatively on material obtained by fine-needle aspiration.

Prognostic value of DNA analysis in colorectal carcinoma

BACKGROUND

Reported experiences regarding the prognostic significance of DNA content in colorectal carcinoma have been a matter of controversy.

METHODS

DNA analysis with image cytometry was performed in 137 patients with colorectal cancer. Only patients who had resection without tumor residual and who did not die postoperatively as a consequence of the operation were entered in the study. At the time of DNA analysis, neither the histomorphologic data nor the relapse-free survival time of the patients were known.

RESULTS

In this investigation the DNA content of tumor cells had no univariate or multivariate influence on the relapse-free survival time. The prognosis was dependent on the tumor localization, depth of tumor infiltration, lymph node metastasis, and grade.

CONCLUSIONS

DNA content provides no additional prognostic information in colorectal carcinoma.

Multifactorial analysis of local recurrences in rectal cancer, including DNA ploidy studies: a predictive model

DNA ploidy studies were performed in 188 patients operated on for rectal cancer. In order to define different risk groups of patients, a stepwise logistic regression was carried out in 138 patients who underwent abdominal "curative" resections. Thirty-seven variables were analyzed. Although several variables were significant, only three improved the prognostic value: (1) more than three positive lymph nodes (p = 0.0007); (2) macroscopic local tumor invasion (p = 0.01); and (3) DNA ploidy (p = 0.03). Standardized discriminant coefficients were used to obtain a model and format for predicting local recurrences. This is the first time that a predictive model for rectal cancer, using DNA ploidy as a variable, is reported. Based on calculated discriminant values (DV), patients can be divided into three subgroups: (1) low risk for local recurrences (DV < -1.9, n = 56)--local recurrences were observed in two patients (3.6%); (2) moderate risk (DV between -1.9 and -0.6, n = 55)--local recurrences occurred in nine patients (16.4%); and (3) high risk (DV > -0.6, n = 27)--local recurrences occurred in 14 patients (51.8%). This predictive model for local recurrences has much better prognostic value than Dukes' staging (p < 0.0001).

Staging and surgery for colorectal cancer

Staging of colorectal cancer has become increasingly important to select groups of patients for limited or more extensive surgery, and for adjuvant radiotherapy and chemotherapy. The main treatment is still surgery, but subgroups may benefit from adjuvant therapy, even accepting additional side effects. Accurate staging is necessary to define different treatment groups. A critical review is given of the present methods of clinicopathological staging.

DNA image cytometry in stomach carcinoma. Its relation to histomorphologic parameters and its influence on prognosis

BACKGROUND

The influence of DNA content on the prognosis in stomach cancer is controversial.

METHOD

After curative resection of stomach carcinomas (adenocarcinomas [n = 58]; signet ring cell carcinomas [n = 24]; undifferentiated carcinomas [n = 21]), the influence of the DNA content and histomorphologic parameters on the prognosis was examined.

RESULTS

In the multivariate regression analysis, the prognosis depended on the lymph node status (P = 0.0009), pT stage (P = 0.02), tumor localization (P = 0.03), and histologic type (P = 0.05). The prognosis was independent of the DNA content. Furthermore, the degree of differentiation, operative procedure, safety distance, size of the tumor, and sex and age of the patient also did not influence the prognosis.

CONCLUSIONS

The DNA content of the tumor cells in stomach carcinoma does not influence prognosis.