Metastatic Relapse In Patients Research Articles

Jorge clinical study: 10-year outcomes of risk-adapted radiotherapy defined by multiparametric MRI for prostate cancer.

To analyze the 10-year biochemical relapse-free survival (BRFS), locoregional relapse-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS) in patients diagnosed with localized prostate adenocarcinoma treated with radiotherapy (RT) ± androgen deprivation therapy (ADT), according to the risk groups based on multiparametric magnetic resonance imaging (mpMRI) instead of digital rectal exam (DRE). We retrospectively evaluated 140 consecutive patients diagnosed with localized prostate adenocarcinoma, stratified into different risk groups-low (LR), intermediate (IR), and high (HR) by mpMRI results. After a median follow-up of 104months, in LR group (n = 15), 10-year BRFS was 86.7%, 10-year LRFS was 86.7%, 10-year MFS was 93.3%, and 10-year OS was 100%. In IR group (n = 80), 10-year BRFS was 80.5%, 10-year LRFS was 86.1%, 10-year MFS was 92.6%, and 10-year OS was 76%. In HR group (n = 45), 10-year BRFS was 72.8%, 10-year LRFS was 78.7%, 10-year MFS was 82.1%, and 10-year OS was 77% (2 deaths from prostate cancer). According to mpMRI results, 36 (25.7%) patients change the risk group and 125 (89.28%) patients change the TNM stage. There was a trend for higher metastatic relapse in patients who switched from IR to HR (due to mpMRI) versus the patients who remained in the IR (20%, vs. 1.81% p = 0.059). Multivariate analysis showed that locoregional relapse was strongly associated with distant relapse (OR = 9.28; 95%CI: 2.60-33.31). There were no cases of acute grade 3 toxicity. Late grade 3 genitourinary, gastrointestinal, and sexual toxicity were 2.8%, 0.7%, and 1.2%, respectively. This is the first study with a 10-year median follow-up of patients diagnosed with localized prostate cancer treated with radiotherapy according to the risk groups established by mpMRI. Our findings show that mpMRI is a key tool to diagnose and establish risk groups in these patients, to optimize their treatment.

DIPG-38. PATIENT-DERIVED THREE-DIMENSIONAL AVATARS REVEAL CELL-AUTONOMOUS MECHANISMS DRIVING INVASION AND METASTATIC PROGRESSION IN DIFFUSE MIDLINE GLIOMAS

Abstract Diffuse midline gliomas H3K27-altered are pediatric tumors associated with dismal survival after diagnosis that are characterized by their ability to infiltrate the entire central nervous system. We show that the extent of tumor invasion and metastatic progression represent critical adverse prognostic factors affecting the survival of DMG patients. Yet, no genetic alterations associate to the tumor progression patterns. We therefore used glioma stem cells collected at diagnosis to create patient-specific 3D avatars. We found that their invasive behaviour faithfully predicts metastatic relapse in patients, thus proving DMG spread is mainly an autonomous ability of tumor cells. This relevant modelling strategy revealed the existence of phenotypic entities associated with distinct migration modalities and capacities. Using transcriptomics of both organoids and primary tumors, we identified the biological programs associated with variable invasiveness. Importantly, we show that Bone Morphogenetic Protein 7 (BMP7) signalling is a crucial tumour-autonomous regulator of DMG invasiveness via the control of a phenotypic switch. We further deciphered effectors downstream of BMP7 stimulation as actionable targets to reduce invasion. These findings have two possible therapeutic applications. First, glioma stem cell 3D models represent a tool for tumor phenotypic stratification to rapidly predict patients with exacerbated invasiveness and increased risk of metastatic progression. This may allow to propose whole-brain or cranio-spinal irradiation within weeks after diagnosis to prevent the appearance of distant foci. Second, targeting autocrine and short-range BMP7-related signalling may become a useful adjunct to the current therapeutics, which are mainly directed to control the disease locally.

Abstract 1939: Multimodal prediction of metastatic relapse using federated deep learning outperforms state-of-the-art methods in soft-tissue sarcoma

Abstract Soft Tissue sarcomas (STS) are a group of heterogeneous and complex diseases. Being able to predict the appearance of metastases is key to inform clinical decisions, especially the prescription of perioperative chemotherapy. While multiple methods including multivariable nomograms have been developed to tackle this issue, we leveraged artificial intelligence (AI) to extract information from raw images with Deep-Learning. In this study, we developed SarcNet: a multimodal deep-learning algorithm based on histological slides and clinical variables to predict metastatic relapse in patients affected with limbs and trunk wall STS. Two independent series were investigated simultaneously: Centre Léon Bérard, n=221 and Institut Bergonié, n=390. This study was able to gather a sufficient number of patients in this rare disease by training all the algorithms in a multicentric fashion using Federated Learning (FL). It is one of the first real-world applications of FL in Healthcare which allows to keep patients’ data behind hospital firewalls. The SarcNet algorithm achieved unprecedented performance. By leveraging an AI-driven analysis of digitized whole slide images in addition to clinical variables, our multimodal model achieved a 0.80 AUC to predict 5-year MFS (metastatic free survival) compared to 0.77 for Sarculator (current state-of-the-art nomogram). It also greatly outperformed current standard of care practices like FNCLCC grading that reached an AUC of 0.70. Interpretability investigations of the SarcNet model highlighted histological patterns that drive the prediction of metastatic relapse such as atypia, tumoral cellularity and mitosis. This model could lead to more informed clinical decisions by identifying high-risk patients that could benefit from perioperative chemotherapy. Finally, deeper investigations of the model and the highlighted biomarkers could lead to a better understanding of metastatic relapse in STS Performance of models to predict 5y MFS (AUC evaluated in 5 repeated 5-fold cross validation) Methods Whole cohort (n=611) IB (n=390) CLB (n=221) SarcNet 0.800, 95% CI [0.786-0.814] 0.770, 95% CI [0.750-0.791] 0.842, 95% CI [0.824-0.859] Sarculator 0.767, 95% CI [0.752-0.783] 0.736, 95% CI [0.718-0.755] 0.808, 95% CI [0.785-0.831] FNCLCC (French Federation of Centers for the Fight against Cancer) grading 0.699, 95% CI [0.684-0.714] 0.723, 95% CI [0.708-0.738] 0.637, 95% CI [0.612-0.663] Citation Format: Charles Maussion, Jean-Michel Coindre, Jean-Yves Blay, Kathryn Schutte, Axel Camara, François Le Loarer, Raul Perret, Myriam Jean-Denis, Alexandra Meurgey, Françoise Ducimetiere, Antoine Giraud, Jean-Baptiste Courrèges, Clément Gautier, Etienne Bendjebbar, Jean Du Terrail, Antoine Italiano, Marie Karanian. Multimodal prediction of metastatic relapse using federated deep learning outperforms state-of-the-art methods in soft-tissue sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1939.

Outcome of Patients with Soft-Tissue Sarcomas: An Age-Specific Conditional Survival Analysis.

Soft-tissue sarcomas (STSs) are a group of rare cancers that can occur at any age. Prognostic outcomes of patients with STS are usually established at the time of the patient's initial disease presentation. Conditional survival affords a dynamic prediction of prognosis for patients surviving a given period after diagnosis. Estimates of conditional survival can provide crucial prognostic information for patients and caregivers, guide subsequent cancer follow-up schedules, and impact decisions regarding management. This study aims to estimate conditional survival and prognostic factors in patients with STS according to age at diagnosis (≤75 years and ≥75 years). A total of 6,043 patients with nonmetastatic STS at first diagnosis who underwent complete surgical resection (R0 or R1) were assessed. Cox proportional hazards regression was used to establish prognostic factors of conditional metastasis-free survival and overall survival at 1, 2, and 5 years after diagnosis. Elderly patients have more adverse prognostic features at presentation and tend to receive less aggressive treatment than do younger patients. However, at baseline as well as at each conditional survival time point, the 5-year estimated probability of metastatic relapse decreases in both young and elderly patients and is almost identical in both groups at 2 years and 5 years after initial diagnosis. Prognostic factors for metastatic relapse and death change as patient survival time increases in both young and elderly patients. Grade, the strongest prognostic factor for metastatic relapse and death at baseline, is no longer predictive of metastatic relapse in patients surviving 5 years after initial diagnosis. Leiomyosarcoma is the histological subtype associated with the highest risk of metastatic relapse and death in young patients surviving 5 years after initial diagnosis. The positive impact on the outcome of peri-operative treatments tends to decrease and disappears in patients surviving 5 years after initial diagnosis. Conditional survival estimates show clinically relevant variations according to time since first diagnosis in both young and elderly patients with STS. These results can help STS survivors adjust their view of the future and STS care providers plan patient follow-up. For patients with sarcoma who are followed up years after being treated for their disease, a common scenario is for the patient and caregivers to ask practitioners what the longer-term prognosis may be. The question posed to practitioners may be, "Doc, am I now cured? It's been 5 years since we finished treatment." Survival probability changes for patients who survive a given period of time after diagnosis, and their prognosis is more accurately described using conditional survival. By analyzing more than 6,000 sarcoma patients, an overall improvement was found in the risk of relapse as patients conditionally survive. Prognostic factors for metastatic relapse and death change as patient survival time increases in both young and elderly patients.

Genetic traits for hematogeneous tumor cell dissemination in cancer patients.

Metastatic relapse in patients with solid tumors is the consequence of cancer cells that disseminated to distant sites, adapted to the new microenvironment, and escaped systemic adjuvant therapy. There is increasing evidence that hematogeneous dissemination starts at an early stage of cancer progression with single tumor cells or cell clusters leaving the primary site and entering the blood circulation. These circulating tumor cells (CTCs) can extravasate into secondary tissues where they become disseminated tumor cells (DTCs). Patients might relapse years after initial resection of the primary tumor when DTCs become overt metastases. Current diagnostic strategies for stratification of therapies against metastatic cells focus on the primary tumor tissue. This approach is based on the availability of stored primary tumors obtained at primary surgery, but it ignores that the DTCs might have evolved over years, which can affect the antimetastatic drug response. However, taking biopsies from metastatic tissues is an invasive procedure, and multiple metastases located at different sites in an individual patient show marked genomic heterogeneity. Thus, capturing CTCs from the peripheral blood as a "liquid biopsy" has obvious advantages in particular when repeated sampling is required for monitoring therapies in cancer patients. However, the biology behind tumor cell dissemination and its contribution to metastatic progression in cancer patients is still subject to controversial discussions. This manuscript reviews current theories on the genetic traits behind the spread of CTCs and progression of DTCs into overt metastases.

S-20 : Exploiting the type-1 interferon pathway as a biomarker and therapeutic target for metastatic cancer

It has been well described that the initiation and progression of some cancers is tightly controlled by tumour immunosurveillance. Our recent findings suggest that in breast cancer, the balance of pro-tumour and anti-tumour immune responses is critical in dictating metastatic cell survival and outgrowth. We revealed that tumour cells secrete type I IFN and that loss of this signalling is a tumour cell intrinsic mechanism of evading metastasis-specific immune responses and promoting bone metastasis. We have demonstrated that restored type I IFN signalling in mice bearing 4T1.2 breast tumour cells significantly reduces bone metastasis and that metastasis suppression is linked to NK cell activation and decreased accumulation of immune suppressor cells [1] . The key role of the host immune system in responding to tumour cell-derived IFN has also been verified using mice deficient in the type I IFN receptor (Ifnar1). In these studies, the lack of host Ifnar1 increased the incidence of bone metastasis in mice bearing breast tumours of varying metastatic potential. Our current investigations also extend to orthotopic models of prostate cancer where similar observations of increased metastasis are seen in Ifnar1 null animals. Subsequent ex-vivo studies have confirmed a crucial role of IFN signalling to NK cells in tumour cell recognition. These findings have clinical relevance as decreased primary tumour expression of the type I IFN signature or key interferon regulatory factors predict an increased risk of metastatic relapse in breast cancer patients. Additionally, we have now demonstrated potent anti-metastatic effects of IFN-based therapeutics alone or in combination with chemotherapeutics. Our studies are now focused on refining the prognostic markers that best predict metastatic relapse in patients and investigating the therapeutic window where restoring such immune responses is critical in metastasis suppression.

Systemic treatment in the management of head and neck cutaneous malignancies

For many advanced cutaneous malignancies, combined modality approaches with surgery, radiation, and systemic treatment with chemotherapy and/or biotherapy can maximize outcome for skin cancers of head and neck regions. Use of systemic therapies when given together or separately from radiation therapy, as the case may be, can often lead to better outcomes, with less overall morbidity and a higher likelihood of complete extirpative surgery. Good examples of this concept would be the use of concurrent chemoradiation for locally advanced squamous cell carcinoma of the skin, in which very large invasive tumors can be rendered dramatically smaller, if not completely gone. A novel oral biological drug that targets the Hedgehog signaling pathway, vismodegib, can shrink initially locally advanced unresectable basal cell carcinomas to a resectable, if not completely regressed, and hence curable state with the need for less aggressive and potentially disfiguring surgery. Adjuvant systemic therapies given after definitive surgery may also improve survival by reducing the likelihood of metastatic relapse in patients with aggressive melanoma or Merkel cell carcinoma. This review will provide further detail with regard to the use of some of the available systemic treatments for the common cutaneous malignancies of the head and neck, including squamous cell carcinoma, basal cell carcinoma, malignant melanoma, and Merkel cell carcinoma, to provide a better understanding of the multimodality approaches in these malignancies.

Expression of Chemokine Receptor CCR6 as a Molecular Determinant of Adrenal Metastatic Relapse in Patients With Primary Lung Cancer

BackgroundRecent studies suggest that chemokines are involved in organ-specific metastatic relapse. We evaluated the potential implications of chemokine receptors in the development of adrenal metastasis after complete resections of primary non–small-cell lung cancer. Patients and MethodsWe studied a unique cohort of 21 primary lung cancers with matched adrenal metastases for the expression of CX3CR1, CXCR4, CCR6, and CCR7, using immunohistochemistry. ResultsAlthough CXCR4, CX3CR1, and CCR7 were independently expressed in primary and corresponding metastases, CCR6 was clearly overexpressed in adrenal metastases, compared with corresponding primary tumors. Moreover, CCL20, the ligand of CCR6, was preferentially expressed in adrenal tissues that developed metastases. ConclusionWe report for the first time (to the best of our knowledge) a potential role for the CCR6 receptor in the organ orientation of the development of metastases in lung cancer. We demonstrated a statistically significant overexpression of CCR6 in adrenal metastases compared with primary lung tumors, indicating that the increased production of CCL20 in adrenal glands might contribute to the selective recruitment of CCR6-expressing cancer cells in lung cancer. This study, in concordance with the data obtained in animal models, suggests that the chemokine receptor family constitutes a biologic support of the “seed and soil” theory.

Bone marrow micrometastases in different solid tumors: Pathogenesis and importance

Early dissemination of cancer cells from the primary tumor via the circulatory system may result in the formation of microscopic metastatic deposits (micrometastases, MMs) in secondary compartments such as the bone marrow (BM), where there is a favorable environment for their subsequent growth and spread. MMs are considered the main reason for metastatic relapse in patients with early stage solid cancers after resection of the primary tumor. Although the molecular pathways leading to MMs remain only partly understood, there is increasing evidence that the detection of MMs in BM aspirates at the time of primary diagnosis is an independent prognostic factor, with a major influence in the stratification of these patients for adjuvant clinical treatment. Further potential applications of the detection of MMs include their use in monitoring therapeutic response or even in revealing targets for novel systemic therapies. All these intriguing possibilities are intensely investigated and carry great promise for radical improvements in the assessment and treatment of several epithelial cancers which are currently to blame for the majority of cancer-related deaths in the industrialized world.

Genetic polymorphism of CYP2D6: a critical factor for early metastatic relapse in patients treated with adjuvant tamoxifen

Today's drug therapy regimens rely on the anticipated relation between drug dose, acquired plasma level and desired effect. However, the capacity of individual patients to absorb and metabolise drugs may differ significantly, part of which is due to genetic factors. These genetic factors can be used to predict the drug metabolizing potential of patients before starting therapy. A major challenge is to identify the genetic polymorphisms which are relevant for a particular therapy and to determine the clinical consequences with respect to dosing, or choice of drug, based on the outcome of pharmacogenetic analyses. For the cytochrome P450 system, which catalyzes oxidative reactions, many new genetic polymorphisms have been identified in the last years. In this review, the current knowledge of cytochrome P450 polymorphisms with respect to cancer treatment is described, highlighting the potential of reaching considerable benefit from personalized therapy, either by improving efficacy or reducing the toxicity of current treatment regimens. This review specifically addresses the knowledge today on cytochrome P450 pharmacogenetics for tamoxifen, docetaxel, paclitaxel, cyclophosphamide, ifosfamide, imatinib, gefitinib, irinotecan, etoposide, teniposide, thalidomide and vincristine therapies, discussing its current potential for individualized therapy based on cytochrome P450 genetic polymorphisms.

Excellent Local Control Rates and Distinctive Patterns of Failure in Myxoid Liposarcoma Treated With Conservation Surgery and Radiotherapy

To evaluate the local control rates and patterns of metastatic relapse in patients with localized myxoid liposarcoma treated with conservation surgery and radiotherapy (RT). Between 1960 and 2003, 127 patients with non-metastatic myxoid liposarcoma were treated with conservation surgery and RT at our institution. The median patient age was 39 years (range, 14-79 years). Of the 127 patients, 46% underwent preoperative RT (median dose, 50 Gy) and 54% underwent postoperative RT (median dose, 60 Gy). Also, 28% received doxorubicin-based chemotherapy as a part of their treatment. The median follow-up was 9.1 years. The overall survival rate at 5 and 10 years was 87% and 79%, respectively. The corresponding disease-free survival rates were 81% and 73%. The local control rate at > or =5 years was 97%. The actuarial rate of distant metastases at 5 and 10 years was 15% and 24%, respectively. Of the 27 patients who developed distant metastases, 48% did so in the retroperitoneum, 22% in other extrapulmonary soft tissues, 22% in the lung, 15% in bone, and 4% in the liver. The results of our study have shown that RT and conservation surgery for localized myxoid liposarcoma provide excellent local control. Distant metastatic relapse tended to occur in the retroperitoneum and other nonpulmonary soft tissues. Therefore, staging and surveillance imaging should include the abdomen and pelvis, as well as the thorax, for patients with localized myxoid liposarcoma.

Expression of chemokine receptors predicts the site of metastatic relapse in patients with axillary node positive primary breast cancer

BackgroundRecent studies have suggested that chemokine receptors are involved in development of organ-specific pattern of metastases. In the present study, we evaluated the association between the chemokine receptors expressed in primary tumor cells and the site of metastatic relapse in patients with breast cancer. MethodsPrimary tumors were obtained from 142 patients with axillary node–positive breast cancer and stained for CX3CR1, CXCR4, CCR6, and CCR7 expression. All statistical analyses were adjusted for systemic post-operative treatment. ResultsAfter a median follow-up of 13 years, none of the chemokine receptors was associated with overall survival or disease free survival. However, expression of chemokine receptors was found to be associated with increased risk of relapse in certain organs. By estimating the Mantel-Haenszel odds ratios (OR), CXCR4 was associated with increased risk of metastasis to the liver (OR = 3.71, P = 0.005), CX3CR1 was associated with metastasis to the brain (OR = 13.18, P = 0.01). Patients with CCR6 positivity were more likely to develop a first metastasis in the pleura (OR = 2.82, P = 0.06). In addition, CCR7 expression was associated with the occurrence of skin metastases (11% versus 0%, P = 0.017). InterpretationExpression of chemokine receptors in the primary tumor predicts the site of metastatic relapse in patients with axillary node positive breast cancer. This study, in concordance with the data obtained in animal models, suggests that the chemokine receptors family could be the biological support of the ‘seed and soil’ theory.

The pattern of chemokine receptors expressed by tumor cells predicts the site of metastatic relapse in patients with axillary node positive breast cancer

9501 Background: Some types of tumors present an organ-specific pattern of metastases. Although studies performed in animal models present strong evidence for a role of chemokine receptors in this phenomenon, there is no clinical study that specifically correlates the pattern of chemokine receptor expression with the site of metastases. In the present study, we have looked at the correlation between the chemokine receptors expressed by primary tumor cells and the site of metastatic relapse in patients with T1–3N+M0 breast cancer. Methods: CX3CR1, CXCR4, CCR6 and CCR7 expressions were evaluated by immunohistochemistry on primary tumors obtained from 142 patients with T1–3N+M0 breast cancer. These patients were included in a prospective trial between 1972 and 1979. None of the patients received adjuvant chemotherapy. Results: CX3CR1, CXCR4, CCR6, CCR7 expressions were found in 59 (43%), 42 (31%), 45 (34%) and 93 (66%) patients respectively. The expression of chemokine receptors did not correlate with any clinical characteristics, except a higher rate of very young patients (<35 year) in the CXCR4+ subgroup (14% vs 4%, p=0.04). After a median follow-up of 25 years, 75 patients (53%) have presented a metastatic relapse. The expression of chemokine receptors did not predict the metastasis-free survival, nor the overall survival. On the other hand, the pattern of chemokine receptor expression predicted the site of metastatic relapse. CX3CR1 staining predicted the occurence of brain metastases (14% vs 1%, p=0.004). CXCR4 staining predicted the occurrence of liver metastases (38% vs 14%, p=0.001) and lung metastases (28% vs 16%, p=0.05). CCR7 predicted the occurrence of skin metastases (11% vs 0%, p=0.03) and CCR6 predicted the occurrence of malignant pleural effusion (24% vs 10%, p=0.04). Conclusion: The study shows that the pattern of chemokine receptors expressed by tumor cells predicts the site of metastatic relapse in patients with T1–3N+M0 breast cancer. This study, in line with data obtained in animal models, may suggest in a clinical model that the chemokine receptor family could be the biological support of the << seed and soil >> theory. No significant financial relationships to disclose.

Expression of 17-1A antigen and complement resistance factors CD55 and CD59 on liver metastasis in colorectal cancer

Despite radical surgery, the prognosis for colorectal cancer patients with liver metastases has not changed markedly. Furthermore, no standard adjuvant therapeutic regimen has been developed. Adjuvant therapy with monoclonal antibodies (e.g., against 17-1A), which has been shown to be effective in preventing metastatic relapse in patients with Dukes' C colorectal cancer, might be a promising approach for these patients. However, the cytotoxic effects of monoclonal antibodies can be blocked by coexpression of complement resistance factors that inhibit antibody-dependent complement-mediated cytotoxicity. We therefore analyzed immunohistochemically the expression of 17-1A and the membrane-bound complement resistance factors CD55 and CD59 on metastatic tumor cells in the livers of 71 patients with colorectal carcinoma who had undergone resection of their metastases with curative intent. In 67 (94%) of 71 patients, liver metastases with homogeneous expression of 17-1A was seen. Heterogeneous expression of 17-1A was seen in four patients (6%). Heterogeneous expression of CD55 or CD59 was observed in 8 (11%) of 71 patients and 4 (6%) of 71 patients, respectively. None of the patients showed homogeneous expression of either CD55 or CD59. All patients with CD55 or CD59 expression showed homogeneous 17-1A expression, whereas none of the four patients with heterogeneous 17-1A expression was positive for CD55 or CD59. Our data indicate that 17-1A is widely expressed on liver metastases of patients with colorectal carcinoma. Therefore patients with completely resected liver metastases might be suitable candidates for adjuvant therapy with and-17-1A antibody since only a few of these lesions showed coexpression of complement resistance factors.

Early cancer cell dissemination and late metastatic relapse: clinical reflections and biological approaches to the dormancy problem in patients

Two clinical entities, unknown-primary cancer and inadvertent transmission of cancer with organ transplants are reviewed and discussed in the context of early and occult tumor cell dissemination. Both entities are taken as chief witnesses for cell dissemination being an early event in tumor progression. The involuntary transmission of tumor by organ grafts directly supports the notion that very few quiescent cells lodging at improbable sites such as kidney or heart suffice to generate de novo metastatic disease in the organ recipient. As to the nature of the cells and their biological and clinical significance a short review is given on the detection of disseminated cells in bone marrow and their prognostic significance for a metastatic relapse in patients with resected primary tumors. A novel single-cell genomic analysis is described, that allows the detection of multiple chromosomal aberration in single tumor cells.

Micrometastatic bone marrow involvement: detection and prognostic significance.

The present review focuses on the methodology and clinical significance of new diagnostic approaches to identify individual cancer cells present in bone marrow, both as a frequent site of metastasis formation and an indicator organ for hematogenous tumor cell dissemination. The steadily increasing number of studies on this issue is characterized by considerable methodological variations of important variables, such as the size of the study population, and the reliability of monoclonal antibodies used for tumor cell detection. Emerging data indicate that this disturbing heterogeneity might be overcome by the use of reliable and specific anti-cytokeratin antibodies (for example, A45-B/B3) as, for the time, standard markers for the detection of micrometastatic tumor cells in bone marrow. Prospective clinical studies have shown that immunoassays based on anti-CK antibodies identify patients' subgroups with a poor clinical prognosis with regard to early metastasis manifestation and reduced overall survival in various epithelial tumor entities, including breast, colon, rectum, stomach, esophagus, prostate, renal, bladder, and non-small cell lung cancer. The immunocytochemical assays may be therefore used to improve tumor staging with potential consequences for adjuvant therapy, because disseminated cells appeared to be dormant, non-cycling (for example Ki-67 antigen-negative) cells, suggesting a resistance to cell-cycle dependent therapy, such as chemotherapy. Therefore, cell-cycle independent antibody-based immunotherapy might be an interesting option to complement chemotherapy. Another promising clinical application is monitoring the response of micrometastatic cells to adjuvant therapies, which, at present, can only be assessed retrospectively after an extended period of clinical follow-up. The outlined current strategies for detection and characterization of cancer micrometastasis might help to design and control new therapeutic strategies for secondary prevention of metastatic relapse in patients with operable primary carcinomas.

Detection and clinical importance of micrometastatic disease.

Metastatic relapse in patients with solid tumors is caused by systemic preoperative or perioperative dissemination of tumor cells. The presence of individual tumor cells in bone marrow and in peripheral blood can be detected by immunologic or molecular methods and is being regarded increasingly as a clinically relevant prognostic factor. Because the goal of adjuvant therapy is the eradication of occult micrometastatic tumor cells before metastatic disease becomes clinically evident, the early detection of micrometastases could identify the patients who are most (and least) likely to benefit from adjuvant therapy. In addition, more sensitive methods for detecting such cells should increase knowledge about the biologic mechanisms of metastasis and improve the diagnosis and treatment of micrometastatic disease. In contrast to solid metastatic tumors, micrometastatic tumor cells are appropriate targets for intravenously applied agents because macromolecules and immunocompetent effector cells should have access to the tumor cells. Because the majority of micrometastatic tumor cells may be nonproliferative (G0 phase), standard cytotoxic chemotherapies aimed at proliferating cells may be less effective, which might explain, in part, the failure of chemotherapy. Thus, adjuvant therapies that are aimed at dividing and quiescent cells, such as antibody-based therapies, are of considerable interest. From a literature search that used the databases MEDLINE(R), CANCERLIT(R), Biosis(R), Embase(R), and SciSearch(R), we discuss the current state of research on minimal residual cancer in patients with epithelial tumors and the diagnostic and clinical implications of these findings.

Serum testosterone—A significant determinant of metastatic relapse for irradiated localized prostate cancer

Objectives To determine if the serum total testosterone concentration correlates with the outcome for men irradiated for clinically localized prostate cancer. Methods The outcome-local, nodal, distant metastatic, and biochemical—for 486 men with clinically localized prostate cancer treated by radiation and for whom testosterone levels were available was analyzed. No patient received adjuvant androgen ablation. Patient tumor stages were T1: 129 (27%); T2: 187 (38%); and T3/T4: 170 (35%). Median follow-up was 41 months. Results Pretreatment testosterone values ranged from 109 to 1121 ng/dL, with a mean of 417 ng/dL and a median of 398 ng/dL. The distribution of patients according to a four-tier testosterone grouping was testosterone level of 300 ng/dL or less, 108 (22%); testosterone level greater than 300 ng/dL but not more than 400 ng/dL, 141 (29%); testosterone level greater than 400 ng/dL but not more than 500 ng/dL, 123 (25%); and testosterone level greater than 500 ng/dL, 114 (23%). There were statistically significant but trivial correlations between testosterone level and age, T-stage, and acid phosphatase level. There was no correlation between testosterone and prostate-specific antigen (PSA) levels. There was a highly significant correlation between testosterone level and metastatic relapse. Patients with testosterone level greater than 500 ng/dL had a markedly higher 6-year metastatic rate (16%) than those with a testosterone level of 500 ng/dL or less (4%) ( P=0.001). In multivariate analysis, testosterone level was an independent determinant of metastatic relapse, second only to PSA level and of about the same power as T-stage. Gleason grade, although significant, was less so than testosterone level. The correlation of testosterone level to outcome appeared to be specific for metastatic relapse having no relation to local outcome. Likewise, high testosterone levels were not associated with acceleration of postradiation serum PSA kinetics. Conclusions There is a highly significant correlation between pretreatment testosterone level and metastatic relapse in patients with clinically localized prostate cancer treated with radiation. As serum testosterone increases, so too does metastatic relapse. This relationship appears to take a decided turn for the worse at testosterone levels exceeding 500 ng/dL.

Immunocytochemical double staining of cytokeratin and prostate specific antigen in individual prostatic tumour cells

Early dissemination of malignant cells is the main cause for metastatic relapse in patients with solid tumours. By use of monoclonal antibodies (mAbs) specific for cytokeratins, disseminated individual epithelial tumour cells can now be identified in mesenchymal organs such as bone marrow. Further to characterize such cells in patients with prostate cancer, an immunocytochemical procedure was developed for simultaneous labelling of cytokeratin component no. 18 (CK18) and prostate specific antigen (PSA). In a first step, cells were incubated with mAb ER-PR8 against PSA and secondary gold-conjugated goat anti-mouse antibodies. In a second step, biotinylated mAb CK2 to CK18 was applied as primary antibody and subsequently incubated with complexes of streptavidin-conjugated alkaline phosphatase, which were developed with the Newfuchsin substrate. The binding of gold-labelled antibodies was visualized by silver enhancement. The sensitivity and specificity of the technique was demonstrated on cryostat sections of hyperplastic prostatic tissue, and cytological preparations of LNCaP prostatic tumour cells. Double staining was restricted to cells derived from the secretory epithelium of the prostate. Cross-reactivity between both detection systems was excluded by several controls, including the use of unrelated antibodies of the same isotype and the staining of CK18+/PSA- HT29 colon carcinoma cells. CK18+ cells co-expressing PSA were found in bone marrow aspirates from 5 out of 13 patients with carcinomas of the prostate, a finding that is consistent with the relative fraction of double-positive LNCaP cells. The specificity of CK18 for epithelial tumour cells in bone marrow was supported by negative staining of 12 control aspirates from patients with benign prostatic hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)