Serum tumour marker regression rate following chemotherapy for malignant teratoma

Serum Tumour Markers in Testicular Germ Cell Tumours: Frequencies of Elevated Levels and Extents of Marker Elevation Are Significantly Associated with Clinical Parameters and with Response to Treatment

Introduction

Although serum tumor markers beta human chorionic gonadotropin (bHCG), alpha-fetoprotein (AFP), and lactate dehydrogenase (LDH) are well-established tools for the management of testicular germ cell tumours (GCTs), there are only few data from contemporary cohorts of primary GCT patients regarding these biomarkers. Our aim was to evaluate marker elevations in testicular GCTs and to document their associations with various clinical characteristics.

Patients and Methods

A total of 422 consecutive patients with GCTs were retrospectively analysed regarding serum levels of bHCG, AFP, and LDH during the course of treatment. Additionally, the following characteristics were recorded: histology, age, laterality, clinical stage (CS), pT-stage, and tumour size. Marker elevations were first tabulated in dichotomized way (elevated: yes/no) in various subgroups and second as continuous measured serum values. Descriptive statistical methods were employed to look for differences among subgroups and for associations of elevations with clinical parameters.

Results

In all GCT patients, the frequencies of elevated levels of bHCG, AFP, LDH, and bHCG or AFP were 37.9%, 25.6%, 32.9%, and 47.6%; in pure seminomas 28%, 2.8%, 29.1%, and 30.3%; and in nonseminoma 53.0%, 60.1%, 38.7%, and 73.8%. Significant associations were noted with pT-stages >pT1, clinical stages >CS1, tumour size, and younger age. Frequencies of marker elevations dropped significantly after treatment, but LDH levels remained elevated in 30.5%-34.1%. Relapsing patients (n=27) had elevated levels of bHCG, AFP, and LDH in 25.9%, 22.2%, and 29.6%, respectively, thirteen of whom with a changed marker pattern.

Conclusions

The classical GCT-biomarkers correlate with treatment success. Clinical utility is limited due to proportions of < 50% of patients with elevated levels and the low specificity of LDH. The elevation rates are significantly associated with histology, clinical and pT-stages, tumour size, and younger age. Individual marker patterns may change upon relapse. Clinically, ideal biomarkers are yet to be found.

Serum Tumor Marker Half-Life during Chemotherapy in Patients with Germ Cell Tumors

Approximately 80% of previously untreated men with metastatic germ cell tumors will be cured with cisplatin-based chemotherapy. Serum levels of alpha fetoprotein (AFP) or human chorionic gonadotropin (HCG) or both are increased in most of these patients. Pre-treatment clinical characteristics can be used to distinguish between “good” and “poor” risk patients who are either highly likely or unlikely to achieve a complete remission, respectively. A slow rate of decline of either AFP or HCG or both has been associated with an inferior survival in both good and poor risk patients. In multivariate analysis, the pre-treatment risk status and the post-treatment clearance of markers were independent and equal prognostic variables. Similarly, in patients receiving cisplatin + ifosfamide-based salvage chemotherapy, the rate of decline of HCG was an independent predictor variable in addition to the primary site and pre-treatment HCG levels for both overall and event-free survival. Prolonged half-life clearance of serum tumor markers is an important prognostic variable in both previously untreated as well as previously treated germ cel tumor patients. Treatment strategies can be based on marker clearance and prospective clinical trials are warranted.

Afp and Hcg in Germ Cell Tumors

The high specificity and sensitivity of testicular tumor markers make them particularly useful in the management of these neoplasms. Basal value represents an independent prognostic variable, influencing the choice of therapy. An increase in marker level before chemotherapy could also acquire a powerful prognostic significance. The decay curve pattern is indicative of the radicality of surgery. Also during chemotherapy the behavior of markers conditions further therapeutic strategies.

Predicting outcome to chemotherapy in patients with germ cell tumors: the value of the rate of decline of human chorionic gonadotrophin and alpha-fetoprotein during therapy

PURPOSE

The prognostic significance of the rate of decline of the serum tumor marker alpha-fetoprotein (AFP) and human chorionic gonadotrophin (HCG) during the first two cycles of chemotherapy in germ cell tumor (GCT) patients was initially reported by us, but its value has been debated. We re-examined this issue in the context of the International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification system and investigated the role of including in the analysis patients whose markers normalized early.

PATIENTS AND METHODS

One hundred eighty-nine GCT patients with elevated AFP/HCG marker values treated with platinum-based chemotherapy between 1986 and 1998 were included in this analysis. Patients were classified as good, intermediate, or poor risk by the IGCCCG criteria and as having satisfactory or unsatisfactory marker decline. Risk and marker decline were correlated with response, event-free survival, and overall survival.

RESULTS

Satisfactory marker decline predicted improved complete response (CR) proportion and event-free and overall survival (P <.0001). The CR proportion, 2-year event-free, and 2-year overall survival rates for patients with a satisfactory and unsatisfactory marker decline were 92% versus 62%, 91% versus 69%, and 95% versus 72%, respectively. Marker decline remained a significant variable for all three end points when adjusted for risk (P <.01) with the outcome differences most pronounced in the poor-risk group.

CONCLUSION

The rate of marker decline during chemotherapy has prognostic value independent of risk and may play a significant role in the management of poor-risk patients. It is appropriate to include patients whose markers normalized early.

Prognostic significance of marker half-life during chemotherapy in non-seminomatous germ cell testicular tumors

Decrease in serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) levels is considered as a response during chemotherapy of non-seminomatous germ cell testicular tumors, but data on the prognostic significance of marker half-life remains inconclusive. Serum marker half-life was evaluated in 34 patients with elevated markers, receiving chemotherapy (CT). Marker half-life was calculated from the natural logarithm of the sequential AFP or HCG concentrations. The correlation between event-free (EFS) and overall survival (OS) with unfavorable half-lives of AFP and HCG was evaluated. Median actual half-life (AHL) AFP was 3.9 days (range, 1.4-21.5) and median AHL HCG was 4.4 days (range, 1.4-21.0); 82% of the patients had a satisfactory initial decline in AFP, and 71% had a satisfactory initial decline in HCG. There was a significant difference in EFS and OS between the two groups of patients with an AFP half-life < 7 days and > 7 days. HCG half-life did not adversely affect EFS and OS. The correlation of better EFS and OS with appropriate AFP marker half-life during chemotherapy could provide a dynamic method, which could complement the standard baseline prognostic factors, for the prediction of prognosis.

125I-labelled human chorionic gonadotrophin (hCG) as an elimination marker in the evaluation of hCG decline during chemotherapy in patients with testicular cancer

The rate of reduction in the concentration of serum human chorionic gonadotrophin (hCG) following chemotherapy for germ cell tumours may follow a complex pattern, with longer apparent half-life during later stages of chemotherapy, even in patients treated successfully. The commonly used half-life of less than 3 days for hCG to monitor the effect of chemotherapy in patients with germ cell tumours of the testis may represent too simple a model. 125I-labelled hCG was injected intravenously in 27 patients with germ cell tumours and elevated hCG during chemotherapy. The plasma radioactivity and hCG concentrations were followed. During chemotherapy, the plasma disappearance of hCG showed a biphasic pattern, with an initial fast and a later slow component in all patients. Using the steep part of the hCG plasma disappearance curve, five patients who achieved long-term remission had half-lives longer than 3 days (3.6-6.8 days), whereas four out of five patients not achieving long-term remission had half-lives shorter than 3 days. After the third treatment cycle, eight patients who achieved long-term remission had hCG half-lives longer than 3 days (7.4-17.0 days). In these patients, the plasma disappearance of [125I]hCG was equivalent to that of hCG. Thus, the slow decline of hCG represented a slow plasma disappearance rather than a hCG production from vital tumour cells and could, consequently, not be used to select patients for additional or intensified chemotherapy. The concept of a fixed half-life for plasma hCG during treatment of hCG-producing germ cell tumours is inappropriate and should be revised. Difficulties in interpreting a slow decline of hCG may be overcome by comparing the plasma disappearance of total hCG with the plasma disappearance of [125I]hCG.

Testicular cancer

The following article provides a comprehensive review of male germ cell tumors; the pathology and the clinical manifestations of the tumors are discussed, as are the modern concepts of clinical staging. Patients with bulky stage II and stage III non-seminomatous germ cell tumors are treated with chemotherapy. The new international classification system has provided a very useful way to categorize these patients by prognosis. Patients with good- or intermediate-risk tumors may be treated with 3 courses of cisplatin, etoposide, and bleomycin (BEP) or 4 courses of etoposide and cisplatin (EP), and more than 90% of these patients will survive. Randomized trials have shown that, if only 3 courses of chemotherapy are to be given, the substitution of carboplatin for cisplatin and the omission of bleomycin are deleterious to outcome. Patients who still have a significant residual mass and normal markers after treatment should undergo a surgical resection of the residual tumor. Patients who are classified by the international classification system as having poor-risk tumors have about a 50% likelihood of survival, and many of these patients will require surgical resection of a residual tumor after chemotherapy. No randomized trial has proved a regimen to be superior to that of 4 courses of BEP. Currently, an ongoing trial is evaluating the effect of the early use of high-dose therapy in combination with hematopoietic rescue in patients with these types of tumors. Patients with small-volume stage II tumors are generally treated with retroperitoneal lymph node dissection (RPLND). About 25% of the patients selected for this procedure will actually have pathologically negative nodes. Those with positive nodes may elect to receive adjuvant chemotherapy (2 courses of BEP), which will almost always prevent relapse. An alternate approach for patients willing to comply with monthly follow-up is surveillance, with chemotherapy deferred until relapse is noted. About 50% of these patients will be cured with surgery (as many as 75% have microscopic disease only). With careful follow-up, those destined to relapse can be treated promptly and at a time when they have small-volume tumors and an excellent prognosis if they go on to receive chemotherapy. Patients with clinical stage I nonseminomatous germ cell tumors may also undergo RPLND, although an acceptable alternative for these patients is surveillance. The advantages and the disadvantages of each approach are discussed. The overall risk of recurrence is about 30%, but there have been patient groups defined that may vary in risk from 10% to 15% up to 50% or more. Patients with advanced seminoma are treated with chemotherapy. When this procedure is used, outcomes are favorable and all patients are either in good- or intermediate-risk groups, according to the international classification system. Patients with small-volume stage II tumors are treated with radiotherapy. Radiation is also generally used for the treatment of clinical stage I patients, although surveillance is growing in prominence as a means to treat these patients. Late effects of treatment are also discussed in this article. Ejaculatory function can be preserved in most patients who have early stage tumors and who undergo RPLND and in some patients who undergo surgery after chemotherapy. The most troubling effect of chemotherapy is the development of etoposide-induced leukemia, a unique--and fortunately rare--clinical entity.

Treatment of poor-risk germ-cell tumors with high-dose cisplatin and etoposide combined with bleomycin

Seventy-two patients with far advanced ('high-risk') germ-cell tumors were treated with cisplatin 40 mg/m2 i.v. and etoposide 200 mg/m2 i.v. daily for 5 days and bleomycin 15 mg/m2 i.v. once a week. At least 3 cycles of this treatment were given at three-week intervals to all patients. Seventy-five percent of the patients obtained CR and 67% are without evidence of disease after a median observation time of 47 months (range 5 to 80 months). Hematologic toxicity was severe and 10% of the patients died due to treatment-related toxicity. Neurotoxicity was a clinical problem in 58% of the patients. Glomerular filtration rate decreased significantly after 3 cycles (29% +/- 16%). No clinically significant pulmonary toxicity was observed. The specific role of high-dose cisplatin in such intensive treatment has until now been the subject of only one randomized study in which no superiority of high-dose cisplatin was found. Significant improvement of therapeutic outcome over that of today's standard treatment conceivably necessitates an even greater increase in dose intensity of the active drugs--or inclusion of new drugs.

Cisplatinum dose dependent response in germ cell cancer evaluated by tumour marker modelling

This study presents an analysis on longitudinal tumour marker series in twenty-two patients with non-seminomatous germ cell cancers treated with cisplatinum (DDP) based combination chemotherapy. Series of alphafoetoprotein (AFP), human chorionic gonadotrophin (HCG) and lactate dehydrogenase (LDH) were analyzed applying a dynamic mathematical marker model. The model analysis provided quantitated values for growth rate and treatment response in the marker producing cells. The analysis showed that LDH had to be above 2,000 U/l to be a trustworthy tumour marker. HCG producing cells tended to grow faster than AFP producing cells, and were 3-5-fold more sensitive to the chemotherapy given than AFP producing cells. Treatment response versus DDP dose appeared to be bi-phasic, but with no significant change in treatment efficiency within the given range of DDP doses.

Clinical use of tumor markers in oncology

The perfect tumor marker would be one that was produced solely by a tumor and secreted in measurable amounts into body fluids, it should be present only in the presence of cancer, it should identify cancer before it has spread beyond a localized site (i.e., be useful in screening), its quantitative amount in bodily fluids should reflect the bulk of tumor, and the level of the marker should reflect responses to treatment and progressive disease. Unfortunately, no such marker currently exists, although a number of useful but imperfect markers are available. The predominant contemporary markers are discussed here by chemical class, as follows: glycoprotein markers, including carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (beta-hCG), and prostate specific antigen (PSA); mucinous glycoproteins, including CA 15-3, CA 19-9, mucinous-like cancer antigen and associated antigens, and CA 125; enzymes, including prostatic acid phosphatase (PAP), neuron specific enolase (NSE), lactic acid dehydrogenase (LDH), and placental alkaline phosphatase (PLAP); hormones and related endocrine molecules, including calcitonin, thyroglobulin, and catecholamines; and, molecules of the immune system, including immunoglobulins and beta-2-microglobulin. The biologic properties of each group of tumor markers are discussed, along with our assessment of their role in clinical medicine today.

Elevated serum tumor markers in patients with testicular cancer after induction chemotherapy due to a reservoir of markers in cystic differentiated mature teratoma

Elevated serum tumor markers in patients with testicular cancer after induction chemotherapy indicate in most instances the presence of residual malignant disease. We describe 2 patients with elevated tumor markers after chemotherapy and before retroperitoneal lymph node dissection who did not prove to have residual malignant disease but cystic differentiated mature teratoma with a high content of alpha-fetoprotein and beta-human chorionic gonadotropin, respectively, in the cysts. It is postulated that leakage of the contents of these cysts to the plasma compartment was responsible for maintaining elevated serum tumor marker levels. Recognition of such entities is of consequence since unnecessary salvage chemotherapy in these patients may be avoided.

Massive congenital intracranial teratoma diagnosed in utero

The authors describe a case of congenital intracranial teratoma. The patient was diagnosed to be hydrocephalic at 29 weeks' gestation, and to have a huge intraventricular mass lesion at 34 weeks' gestation. Subsequently, the patient underwent subtotal resection of the mass, resulting in a significant decrease in the remarkably elevated alpha-fetoprotein in serum and cerebrospinal fluid. Histological analysis revealed a malignant teratoma, also with alpha-fetoprotein-positive elements in the immunohistochemical study.

The growth rate of metastatic non-seminomatous germ cell testicular tumours measured by marker production doubling time--I. Theoretical basis and practical application

Changes in serum tumour marker levels in non-seminomatous germ cell testicular tumours (NSGCTT) are used to monitor tumour growth and response to treatment. A novel method of calculating the actual tumour marker production (TMP) per day is reported; estimation of the rate of change of TMP is a measure of the tumour growth or regression rate. TMP is calculated mathematically from the rate of increase in serum marker level and its natural half life. TMP is assumed to be proportional to the number of marker producing cells in the tumour. TMP was calculated over the time between orchidectomy and the start of chemotherapy. The rate of increase in TMP with time is expressed as the marker production doubling time (MPDT) and is a measure of the growth rate. In a group of 51 patients with metastatic NSGCTT, TMP varied from 0.012 to 5985 iu/l/day (AFP) and 0.08-5404 iu/l/day (HCG). MPDT varied from 0.5 to greater than 80 days (45 cases) for AFP + ve patients and from 1.8 to greater than 80 days (34 cases) for HCG + ve patients; greater than 80% of cases had a MPDT less than or equal to 32 days. In 45/51 (88%) patients, there was no discrepancy in MPDT between markers. The use of changes in serum marker level to follow tumour progression and regression is simple, but the calculation of actual TMP provides clearer information about the change in number of marker producing cells and can be used as non-invasive method for measuring the tumour growth rate of metastatic disease and response to treatment.

Testicular cancer

Testicular cancer, which predominantly occurs in young men, has become increasingly common; it is presently the most common malignancy in men aged 20-34. Despite a lack of knowledge of aetiology, empirical advances, particularly in the management of patients with advanced disease, have been dramatic. Prior to the development of effective chemotherapy in the 1970s, less than 10% of men with metastatic non-seminomatous germ cell tumours were cured; nowadays approximately 90% of patients are potentially curable. The introduction of effective chemotherapy has led to a reappraisal of surgery and radiotherapy in the management of early stage disease and the introduction of a policy of surveillance in patients without evidence of metastases at the time of removal of the primary tumour. Following chemotherapy, surgery is required in approximately 25% of patients with advanced disease to excise residual masses, which in one-fifth of cases will show evidence of residual malignancy. In a proportion of patients, testicular cancer develops on a background of long-standing infertility, whereas in many men there is temporary oligospermia, despite a previous history of fertility. The majority of patients with prior evidence of spermatogenesis recover this function following chemotherapy and there is no evidence that children fathered by such patients have an increased risk of malformation. Despite physician optimism and excellent prospects for cure, significant psycho-social morbidity is associated with the diagnosis and treatment of testicular cancer. Factors contributing to this are being identified and will lead, hopefully, to the minimisation of such problems by appropriate intervention.

Half-life of alpha-fetoprotein in patients with a teratoma, endodermal sinus tumor, or hepatoblastoma

To evaluate the AFP-concentration postoperatively and/or during chemotherapy treatment, a retrospective study was carried out on 14 patients with a teratoma, endodermal sinus tumor (EST), or hepatoblastoma. Eleven patients were operated. Eight of the 11 patients showed postoperatively a linear decline in their AFP concentration. The half-life was about 6 days. In the group of patients that underwent a noncomplete resection, both a linear and a nonlinear declining pattern was seen. The patients that underwent a complete resection showed only a linear decline in the AFP concentration. No relationship was found between the reduction pattern of the AFP and the development of recurrences. The development of a recurrence was accompanied by an increasing AFP concentration.

Prognosis following chemotherapy for metastatic malignant teratoma

A multiple regression analysis was performed of factors affecting the prognosis of 93 patients with metastatic malignant teratoma treated at the Royal Marsden Hospital between 1979 and 1981. In a subgroup of 53 patients, where exact tumour bulk could be calculated from sequential CT scan slices, a correlation was seen between tumour marker level and volume of metastatic disease. On analysis of the risk of relapse after initial chemotherapy, the independent adverse influence was detected of serum AFP greater than 500 micrograms/l and of bulky disease defined by clinical staging. An adverse influence of high serum HCG levels was not seen, probably due to the small number of patients in this series with this presenting feature.

Yolk sac carcinoma of the testis in children

We reviewed the records of 11 patients with yolk sac carcinoma of the testis seen at the Children's Hospital of Philadelphia from 1971 through 1983. Each child was less than 2 years old at diagnosis, and each had stage I disease (localized to the testicle). Initial management consisted of radical inguinal orchiectomy in all 11 patients. Four patients then underwent retroperitoneal node dissection and none had pathological evidence of retroperitoneal tumor spread. After primary surgical management 5 patients received no further initial treatment. Of these 5 patients 3 are alive with no evidence of disease at 1.5, 2.7 and 4.5 years after diagnosis. The tumor recurred in 2 patients, 1 of whom was salvaged with pulmonary radiation therapy and chemotherapy. The other 6 patients received chemotherapy postoperatively and only 1 has suffered relapse. Over-all, of 3 patients in whom pulmonary metastases developed 1 died of tumor and 1 died of treatment-related pneumonopathy. Our experience and that of others have led us to conclude that patients with localized disease and normal postoperative serum alpha-fetoprotein levels do not benefit from retroperitoneal node dissection, postoperative abdominal irradiation or chemotherapy. Patients with retroperitoneal nodal involvement, widely metastatic disease or recurrent disease can be treated successfully with chemotherapy and in some cases with radiation therapy.

Lactate dehydrogenase as a marker for testicular germ-cell tumours

One hundred and eighty-four patients with testicular germ-cell tumours, 92 with seminoma and 92 with non-seminomatous germ-cell tumours (NSGCT) had total lactate dehydrogenase (LD) assay performed at the time of initial staging following orchidectomy. The proportion of patients with elevated plasma LD and the mean plasma LD increased with advancing stage and increasing tumour bulk for both seminoma and NSGCT. Of patients receiving cytotoxic chemotherapy, 87.5% with seminoma and 63% with NSGCT had elevated plasma LD with subsequent levels reflecting regression or progression of disease. Elevated plasma LD levels were seen in four of seven seminoma, and in 18 of 30 NSGCT patients relapsing after primary treatment. The LD assay provides useful information, and complements the routine measurement of alphafetoprotein (AFP) and beta human chorionic gonadotrophin (beta hCG) in the management of patients with testicular germ-cell tumours.

cis-Diammine-1, 1-cyclobutane dicarboxylate platinum II (carboplatin) in the treatment of testicular germ-cell tumours: a preliminary report

Between 1982 and 1985 47 patients with metastatic testicular germ-cell tumours were treated with carboplatin alone or combined with bleomycin and etoposide and/or vinblastine. Of 14 untreated seminoma patients 13 (93%) are free from active disease at 7-38 months (median 12 months). Twenty patients with untreated advanced non-seminomatous testicular germ-cell tumours have been entered into a study of carboplatin, etoposide and bleomycin (CEB) as first-line treatment. Preliminary data show that of 15 men observed for 6-12 months (mean 7.5 months) 11 are disease-free. Toxicity with the single agent and combination has been mild. Of 12 patients receiving carboplatin alone or in combination for relapse after cisplatin chemotherapy 10 showed no response, one a transient complete response and one a partial response consolidated with radiotherapy. On the basis of these preliminary observations it is concluded that carboplatin is an active drug in testicular germ-cell tumours and that cross resistance with cisplatin may be a significant problem.

Placental alkaline phosphatase as a tumour marker in seminoma using the H17 E2 monoclonal antibody assay

Serum samples from 62 patients with seminoma were assayed for placental alkaline phosphatase-like activity using the monoclonal antibody H17 E2, in order to evaluate its utility as a serum tumour marker. Fifteen of 16 patients (94%) with active seminoma had elevated serum PLAP levels. Sixteen of 46 (35%) of patients considered to be in remission had elevated PLAP levels (false positive rate 35%). Fifteen false positive results were considered attributable to concomitant smoking, and if these patients are excluded, only one false positive case was detected. In 7 out of 7 patients sequential PLAP assays reflected clinical response to treatment.