Marjo Hahka-Kemppinen

Tumor doubling times in metastatic malignant melanoma of the uvea: Tumor progression before and after treatment

OBJECTIVE To obtain estimates of growth rate of metastatic uveal melanoma to infer appropriate follow-up programs and to assess the impact of current chemoimmunotherapy regimens. DESIGN Retrospective case series. PARTICIPANTS Of 70 consecutive patients diagnosed with metastatic uveal melanoma from 1986 through 1998, 37 patients who attended regular follow-up and had measurable metastases were eligible for this study. METHODS Tumor doubling time (DT) was calculated by the Schwartz formula using three presumed sizes of metastasis at last negative follow-up. DT was compared according to tumor characteristics, and time of micrometastasis was estimated. MAIN OUTCOME MEASURES Doubling time of untreated and treated metastases. RESULTS Doubling time of untreated metastases ranged from 34 to 220 days (median, 63 days). Regardless of the presumed size of metastasis at last screening, two thirds of the metastases had a DT between 30 and 80 days. No significant correlation between DT and the observed disease-free interval was detected. Assuming constant growth rate, most metastases had predictably initiated within 5 years before primary treatment. Mean DT during active treatment of metastases in 18 patients who did not show an objective response ranged from 25 to 2619 days (median, 255 days). CONCLUSIONS Based on the estimated growth rates, a rational follow-up interval to detect metastatic uveal melanoma would be 4 to 6 months. Primary uveal melanomas that develop clinically detectable metastasis after conservative therapy may micrometastasize several years before treatment. These estimates are rough and must be confirmed by prospective studies. Current chemoimmunotherapy regimens slow down the growth rate of metastases even if objective response is not obtained.

High expression levels of collagenase-1 and stromelysin-1 correlate with shorter disease-free survival in human metastatic melanoma.

Matrix metalloproteinases (MMPs) are proteolytic enzymes capable of degrading extracellular matrix. Their role has been emphasized in tumor invasion, metastasis and tumor‐induced angiogenesis. We studied the expression of collagenase‐1 (MMP‐1), stromelysin‐1 (MMP‐3) and collagenase‐3 (MMP‐13) in 70 melanoma metastases obtained from 56 patients treated with combined chemoimmunotherapy. The patients were divided into 2 groups using a cut‐off point of 0% for MMP‐1 expression and 20% for MMP‐3 expression. We found that patients with MMP‐1 positive metastases (n = 38) had significantly shorter disease‐free survival compared to patients with MMP‐1 negative metastases (n = 18) (median 11.2 vs. 17.0 months, p = 0.0383). The disease‐free survival of patients with high levels of MMP‐3 expression in their metastases (≥20% positive tumor cells, n = 14) was also significantly shorter compared to patients with lower levels of expression (n = 42) (median 5.1 vs. 14.0 months, p = 0.0294). The expression of MMP‐13 did not correlate to survival parameters. We also found that the presence of melanin, a pigment produced by melanocytes, correlated with high expression levels of MMP‐1 (p = 0.0002), MMP‐3 (p < 0.0001) and MMP‐13 (p = 0.0009). The high expression levels of MMP‐13 were also associated with the presence of visceral metastases (p = 0.0284). Our findings suggest that MMP‐1 and ‐3 may have a special role in melanoma metastasis formation and thus they could be used to measure the biological activity of the disease.

A prognostic model and staging for metastatic uveal melanoma

To identify factors that independently contribute to overall survival in Stage IVB uveal melanoma and to subcategorize by prognosis.

Analysis of G1/S checkpoint regulators in metastatic melanoma

We have analyzed the expression of the CDKN1A (p21CIP1), CDKN1B (p27Kip1), TP53, RB1 and MDM2 proteins and tumor cell proliferation by immunohistochemical staining in 59 cases of metastatic melanoma. The genomic status of the CDKN2A (INK4‐ARF, p16/p14ARF), CDKN2B (p15) and CDKN2C (p18) genes was determined by PCR‐SSCP (single‐strand conformation polymorphism) in 46 of these cases. These results were correlated with various clinico‐pathological parameters, including the outcome of combined chemoimmunotherapy. We found positive correlations between the expression of CDKN1A and MDM2 (r = 0.5063, P = 0.001), between the expression of CDKN1B and RB1 (r = 0.5026, P = 0.001), and between RB1 expression and tumor cell proliferation (0.5564, P < 0.001). Two mutations in the CDKN2A (p16) gene were detected, including a novel base change AAC→ATC (Asn to Ile) at codon 71, that also changes the codon 85 of the alternative reading frame gene p14ARF from CAA to CAT (Gln to His). Homozygous deletion at exon 2 of the CDKN2A (INK4‐ARF) gene was detected in six cases. In seven cases, the 540C→G polymorphism in the 3′UTR of the CDKN2A (p16) gene was found in linkage disequilibrium with the 74C→A polymorphism in intron 1 of the CDKN2B gene (P < 0.0001). These cases had significantly lower expression of the TP53 protein (P = 0.0032). Both 540C→G and 580C→T polymorphisms in the 3′UTR of the CDKN2A (p16) gene were associated with significantly shorter progression time from primary to metastatic disease (P = 0.0071). We conclude, that although none of the analyzed cell cycle regulators could be singled out as a major prognostic factor, G1/S checkpoint abnormalities remain one of the most significant factors in the development of malignant melanoma. Genes Chromosomes Cancer 28:404–414, 2000.

Prognostic value of tumour vascularity in metastatic melanoma and association of blood vessel density with vascular endothelial growth factor expression.

Tumour angiogenesis is essential for tumour growth and metastasis. Several lines of evidence indicate that vascular endothelial growth factor (VEGF) is a major regulator both of physiological and pathological angiogenesis. In this study we assessed the blood vessel density and VEGF expression of 94 melanoma metastases of 70 patients by immunohistochemistry, utilizing antibodies against human platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) and VEGF. The number of blood vessels ranged from 4 to 131 vessels/high power field (HPF), with a mean value of 32 vessels/HPF (+/-21) and a median of 29 vessels/ HPF. Survival since diagnosis of the primary disease and from the start of chemoimmunotherapy, as well as the disease-free survival period, was significantly shorter in the high vascularity group of patients compared with the low vascularity group (P< 0.05 and P< 0.01, respectively). A high overall expression of VEGF in the metastatic melanoma samples was observed. The degree of VEGF expression appeared to have a strong association with the blood vessel density (P= 0.017). This study demonstrates the clinical role of tumour vascularity in the prognosis of patients with metastatic melanoma. In addition, the strong association between vascularity and VEGF expression suggests a crucial role for this growth factor in the neovascularization of metastatic melanoma.

Integrin chains beta1 and alphav as prognostic factors in human metastatic melanoma.

The expression pattern of integrin-type cell adhesion receptors is often changed during malignant transformation. In the present work, we studied the prognostic significance of beta1 and alphav integrin chains for survival of patients with metastatic melanoma. The expression levels of beta1 integrin were also compared with those of Bcl-2, an anti-apoptotic protein, the presence of which is associated with treatment response and survival in melanoma. The expression of beta1 and alphav integrins in 68 melanoma metastases obtained from 55 patients treated with combined chemoimmunotherapy was studied by immunohistochemistry using anti-beta1 and anti-alphav antibodies. The patients were divided into two groups (using a cut-off point of >/= 81%) for beta1 integrin expression levels and into three categories (negative/low, median, high) for alphav integrin expression levels. All tumours were positive for beta1 integrin, and the tumours (n = 6) which had the highest alphav score were also strongly positive for beta1 (94%; P = 0.0055). Patients (n = 43) with 80% or less beta1 integrin-positive tumour cells in their samples had a median disease-free survival (DFS) of 17.0 months, and patients (n = 12) with 81% or more beta1 integrin-positive tumour cells had a DFS of only 5.7 months (P = 0.0001). Patients (n = 32) with low alphav integrin expression levels had shorter DFS (median 12.3 months; P = 0.0146) than patients (n = 20) with median expression levels (median 16.7 months; P = 0.0146). However, three patients who had a very strong alphav expression in their tumours had a median DFS of only 1.8 months (P = 0.0146). Median level expression of beta1 integrin was associated with the presence of Bcl-2 in tumour cells (P = 0.0033). Our results suggest that beta1 and alphav integrin chains are independently expressed in metastatic melanoma and may have an effect on the metastatic potential of melanoma cells.

Chemoimmunotherapy with Bleomycin, Vincristine, Lomustine, Dacarbazine (BOLD), and Human Leukocyte Interferon for Metastatic Uveal Melanoma

A Phase II trial comprising patients with metastatic uveal melanoma (Stage IVB) was undertaken to determine the activity of bleomycin, vincristine, lomustine, and dacarbazine (BOLD) chemotherapy with human leukocyte interferon, as well as the progression‐free and overall survival of the patients according to the substage before treatment.

Serum adhesion molecules and interleukin-2 receptor as markers of tumour load and prognosis in advanced cutaneous melanoma

Cell adhesion molecules are cell surface glycoproteins that may act as mediators in the metastatic process. Soluble interleukin-2 receptor (sIL-2R) is an immunological marker that may also serve as an indicator of tumour progression. Normal and neoplastic cells are capable of releasing these molecules into circulation. We evaluated the association between pretreatment serum levels of soluble intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1 (sVCAM-1) and sIL-2R and metastases and survival in 50 patients with advanced melanoma. The patients with liver and/or bone metastases had significantly higher sICAM-1 levels than those with soft tissue and/or lung involvement (P=0.002). In addition, there was a trend towards higher sIL-2R levels in patients with more metastatic sites (P=0.07). In univariate analysis, the number of metastatic sites (P=0.0001, odds ratio (OR) 3.0, 95% confidence interval (CI): 1.7-5.3), the metastatic site (P=0.01, OR 2.3, 95% CI: 1.2-4.4) and the levels of sICAM-1 (P=0.011, OR 2.5, 95% CI: 1.2-5.0), sVCAM-1 (P=0.036, OR 2.1, 95% CI: 1.0-4.3) and sIL-2R (P=0.0016, OR 3.0, 95% CI: 1.5-6.0) were found to be statistically significant prognostic factors for survival. In multivariate analysis, the number of metastatic sites was the dominant prognostic indicator. After it was excluded from the analysis, the sIL-2R level and the metastatic site were found to be significant. It can be concluded, that high sICAM-1 levels suggest liver metastases and sIL-2R seems to serve as a marker of tumour load in metastatic melanoma. Furthermore, the sIL-2R level appears to add to clinical data predicting the patients outcome.

Immunohistochemically Detectable Bcl-2 Expression in Metastatic Melanoma: Association with Survival and Treatment Response

Objective: The antiapoptotic protein Bcl-2 is supposed to influence the treatment responsiveness of different malignancies. In the present study the prognostic and predictive significance of Bcl-2 expression for survival and response to an administered therapy was explored in patients with metastatic melanoma. Also, the correlation between Bcl-2 expression and proliferation activity of tumor cells was defined to examine the regulatory role of Bcl-2 in proliferation. Materials and Methods: Sixty metastatic melanomas obtained from patients treated with chemoimmunotherapy were examined by immunohistochemistry with anti-Bcl-2 and anti-Ki-67 (MIB-1) antibodies. Proliferation activity was expressed in percentages as MIB-1 index. Results: The presence of Bcl-2 immunoreactivity was associated with a significantly lower MIB-1 index (p = 0.016), and a longer disease-free survival (p = 0.004). The lack of Bcl-2 expression was related to a higher response rate to therapy in comparison to a diffuse and focal pattern of Bcl-2 expression (p = 0.017). Although the presence of Bcl-2 immunoreactivity as such did not correlate with survival after the initiation of chemoimmunotherapy, the focal Bcl-2 expression pattern was strongly associated with a worse prognosis compared to a diffuse expression or a lack of Bcl-2 staining (p < 0.0001). Conclusions: Our results support the role of Bcl-2 in the regulation of cell proliferation and suggest that an increase of metastatic potential and progression of malignant melanoma is associated with a loss of Bcl-2 expression. The lack of Bcl-2 expression could be a predictor of the response to chemoimmunotherapy, whereas the Bcl-2 expression pattern, possibly indicating the heterogeneity of the tumors, might be a potential prognostic factor for survival after the initiation of therapy.

VASCULARITY AND PROGNOSIS OF METASTATIC MELANOMA

The clinical role of vascularity was examined in metastatic melanoma, analyzing the correlation of the blood vessel density and prognosis. Our study included 51 specimens of metastatic melanoma tissue samples from 31 patients treated with combined chemo‐immunotherapy. PECAM‐1 (CD31) was used for assessing vascularity by immunohistochemical staining. On the basis of blood vessel counts, patients were classified into 2 main groups: low and high vascularity. A higher blood vessel density was found to be associated with shorter survival, estimated from the primary diagnosis of the disease (38 months), compared with patients with low blood vessel counts (68 months). A similar tendency was observed when vascularity was correlated to the survival period after the detection of the first metastases (13 vs. 30 months) and with survival since the initiation of chemo‐immunotherapy (8 vs. 16 months). When vascularity and some common prognostic factors, such as age, sex, DNA ploidy and WHO tumor response, were used for a Cox multivariate analysis, vascularity turned out to be the most significant independent prognostic factor. Our results suggest that counting the blood vessels identified by immunohistochemical staining for the endothelial cell‐specific CD31 is a powerful predictor for prognosis in patients with metastatic melanoma and should be considered when selecting patients for therapy. Int. J. Cancer 74:326‐329, 1997.