VP16-213 as a single agent in advanced testicular tumors

Testicular cancer: Biology to bedside

Testicular cancer is the first solid tumor with a remarkably high cure rate. This success was only made possible through collaborative efforts of basic and clinical research. Most patients with distant metastases can be cured. However, the majority of these patients are diagnosed at a young age, leaving many decades for the development of treatment-related complications. This has magnified the importance of research into survivorship issues after exposure to platinum-based chemotherapy. This research, along with research into newer biomarkers that will aid in the diagnosis and surveillance of patients and survivors of testicular cancer, will continue to advance the field and provide new opportunities for these patients. There also remains the need for further therapeutic options for patients who unfortunately do not respond to standard treatment regimens and ultimately die from this disease, including a cohort of patients with late relapses and platinum-refractory disease. Here we discuss the advancements in management that led to a highly curable malignancy, while highlighting difficult situations still left to solve as well as emerging research into novel biomarkers.

Total Synthesis of (+)-Galbulin and Unnatural Lignans

The total synthesis of (+)-galbulin was achieved in 15% yield and 99% ee over eight steps from commercially available 4-veratraldehyde. The key steps include Meyer's asymmetric tandem addition to a chiral 2-oxazoline-substituted naphthalene, a Pd-catalyzed stereospecific decarboxylative γ-arylation, and a formal anti-Markovnikov hydromethylation. In addition, five unnatural lignans were synthesized using the same synthetic strategy.

Long-term complications of chemotherapy for germ cell tumours

Testicular cancer is the most common solid tumour among young males aged 15-35 years. Cisplatin-based combination chemotherapy has changed the outlook of this disease. Disseminated testicular cancer, once uniformly fatal, now has a cure rate of more than 80% with combination chemotherapy. Systematic randomised trials have shown that cisplatin, etoposide and bleomycin (PEB) combination chemotherapy remains the mainstay of treatment. While there is a high cure rate with chemotherapy in patients with this disease, some long-term complications from chemotherapy have now been recognised, including secondary leukaemia, therapy-related solid tumours, nephrotoxicity, neurotoxicity, pulmonary toxicity, vascular toxicity and infertility. Etoposide, a DNA topoisomerase II inhibitor, is a significant risk factor for developing leukaemia; the risk appears to be correlated with the total dose given. Patients receiving cisplatin-based combination chemotherapy for testicular cancer also appear to have a higher relative risk for developing second non-germ cell malignancies; the greatest risks for therapy-related solid tumours were seen with a combination of radiation therapy plus chemotherapy. Long-term vascular toxicities associated with chemotherapy include Raynaud's phenomenon, acute myocardial infarction and cerebrovascular events. Bleomycin is thought to be the most important drug in the pathogenesis of Raynaud's phenomenon, while cisplatin is the most likely agent involved in myocardial infarction. Peripheral neuropathy is the most common form of neurotoxicity observed with cisplatin-based chemotherapy. Risk factors for the development of neural damage include a high cumulative dose of cisplatin, the use of vinblastine and the concomitant development of Raynaud's phenomenon. Cisplatin is also well known to cause significant nephrotoxicity. Approximately 25% of patients present with azoospermia after undergoing combination chemotherapy with a follow up of 2-5 years. Physician awareness of complications associated with chemotherapy is vital to maximise efficacy, minimise toxicity, and preserve quality of life after treatment. Sperm cryopreservation should be considered for patients who desire children. Close monitoring during therapy allows for the early diagnosis of complications, and close follow up of patients after the completion of therapy is necessary to monitor for relapse and development of long-term complications such as myelodysplastic syndrome and leukaemia. Despite these complications, given the potential for cure rates in this young group of patients, the benefits far outweigh the risks.

Chemotherapeutic and surgical strategies for germ cell tumors

Testicular cancer has become a model for a curable neoplasm. Studies of cisplatin combination chemotherapy performed by the author's group allow the following conclusions: (1) short-duration, intensive induction therapy with the most active agents in optimal dosage is more important than maintenance therapy; (2) a modest dose escalation increases toxicity without improving therapeutic efficacy; (3) it is possible to develop curative salvage therapy for refractory germ cell tumors; and (4) preclinical models predicting synergism, such as vinblastine plus bleomycin or cisplatin plus etoposide, have clinical relevance. Testicular cancer has also become a model for new drug development. Cisplatin has been approved by the US Food and Drug Administration for testis and ovarian cancer and VP-16 and ifosfamide for refractory germ cell tumors. The success of these studies confirms the importance of the continued search for new investigational drugs in all solid tumors.

Activity of oxaliplatin in patients with relapsed or cisplatin-refractory germ cell cancer: a study of the German Testicular Cancer Study Group

PURPOSE

To investigate the efficacy and toxicity of oxaliplatin, a diaminocyclohaxane platinum derivative with incomplete cross-resistance to cisplatin in patients with relapsed or cisplatin-refractory germ cell cancer.

PATIENTS AND METHODS

Thirty-two patients with nonseminomatous cisplatin-refractory germ cell cancer or relapsed disease after high-dose chemotherapy (HDCT) plus autologous stem-cell support were treated with single-agent oxaliplatin 60 mg/m(2) on days 1, 8, and 15 repeated every 4 weeks (group 1; n = 16) or oxaliplatin 130 mg/m(2) given on days 1 and 15 of a 4-week cycle (group 2; n = 16). Patients were pretreated with a median of seven (range, three to 13) cisplatin-containing treatment cycles; 78% had received carboplatin/etoposide-based HDCT before oxaliplatin therapy. Twenty-seven patients (84%) were considered refractory (n = 20; 63%) or absolutely refractory (n = 7; 22%) to cisplatin therapy.

RESULTS

Overall, four patients achieved a partial remission (13%; 95% confidence interval, 1% to 24%). Two additional patients achieved disease stabilization. All responses were observed in cisplatin-refractory patients, including three who had not responded to previous HDCT. Patients received a median two cycles of oxaliplatin with a median cumulative dose of 350 mg/m(2). Hematologic toxicity was generally mild, with five patients developing grade 3/4 thrombocytopenia. Nonhematologic side effects consisted mainly of nausea/vomiting. One patient developed grade 3 neurotoxicity.

CONCLUSION

Considering the particularly unfavorable prognostic characteristics of this patient population compared with patients from previous trials for new drugs in germ cell cancer, eg, paclitaxel and gemcitabine, a 13% overall response rate and a 19% response rate in the group treated with oxaliplatin 130 mg/m(2) seems to be of interest. Oxaliplatin may be a palliative treatment option for this patient population, and evaluation in combination regimens is warranted.

Curing metastatic testicular cancer

Our initial studies with cisplatin + vinblastine + bleomycin began 27 years ago in 1974, changing the cure rate for disseminated disease from 5 to 60%. Subsequently, through random prospective clinical trials, we have modified the treatment regimen to reduce both the duration and dosages of the chemotherapy drugs. Cisplatin + etoposide was first used at Indiana University as salvage chemotherapy in 1978, representing the first time that a solid tumor had been cured with second-line chemotherapy. We next did a clinical trial comparing bleomycin + etoposide + cisplatin (BEP) to cisplatin + vinblastine + bleomycin. The BEP regimen was proven to have less toxicity and a higher cure rate and therefore, since 1984, has been standard chemotherapy. More recent studies have evaluated the use of lesser chemotherapy to maintain the same cure rate for patients with good-prognosis disease. Standard therapy for these patients is either three courses of BEP or four courses of EP, and over 90% of these patients will be cured of their disease. Patients who are not cured with their initial BEP chemotherapy are usually treated with salvage chemotherapy. Approximately 50% of these testicular cancer patients will subsequently be cured with salvage chemotherapy with tandem transplant of high-dose chemotherapy with peripheral stem cell rescue. Testicular cancer has become a model for a curable neoplasm. In the early 1970s, metastatic testicular cancer was associated with only 5% survival. Today, with modern chemotherapy and surgery techniques, 80% of patients will survive their disease.

Phase II trial of gemcitabine in refractory germ cell tumors

PURPOSE

This phase II study was designed to determine the toxicity and activity of single-agent gemcitabine in heavily pretreated patients with germ cell tumors.

PATIENTS AND METHODS

From March 1996 through November 1997, 21 patients were enrolled onto a phase II study of gemcitabine 1,200 mg/m2, given on days 1, 8, and 15 every 4 weeks. One patient was unassessable because he never received any gemcitabine. Thirteen of 20 patients had received three prior regimens, and 13 patients were platinum refractory (progression during or within 4 weeks of platinum treatment). There were five extragonadal cases and two patients with late relapse (relapse beyond 2 years).

RESULTS

Gemcitabine was well tolerated. Only one patient had grade 3 or 4 nonhematologic toxicity (grade 3 nausea). Six of 20 patients had grade 3 leukopenia. There were no episodes of granulocytopenic fever, and no patient required platelet transfusion. Three (15%) of 20 patients achieved an objective response, including one complete remission. Three additional patients had a minor radiographic or serologic response.

CONCLUSION

Gemcitabine had definite activity in this heavily pretreated germ cell tumor patient population.

Treatment in germ cell tumours: state of the art

Although the majority of patients with disseminated germ cell tumours can be cured with cisplatin-based chemotherapy, mortality is still up to 20%. Several prognostic factors have been identified to differentiate between patients with a good, intermediate or poor prognosis. In this review we discuss the recent chemotherapy trials, which were designed to reduce toxicity in good-prognosis patients and to improve efficacy in intermediate- and poor-prognosis patients. In good-prognosis patients it is obvious that the omission of bleomycin and the replacement of cisplatin by carboplatin has no place in first-line standard treatment. The reduction of four standard courses of bleomycin, etoposide and cisplatin (BEP) to three is shown possible in one study, but a confirmatory study is currently ongoing in the EORTC. In intermediate- and poor-prognosis patients, the use of new agents or alternating regimens (with or without shortened intervals) did, by now, not improve final outcome. The role of high-dose chemotherapy remains to be determined. Against this background, four courses of standard-dose BEP should still be considered treatment of first choice in the majority of patients with disseminated germ cell tumours. Furthermore, the policy in clinical stage I disease has been reviewed. In clinical stage I seminoma patients the policy is to apply adjuvant radiotherapy, while the strategy in patients with non-seminomatous tumours (surveillance, retroperitoneal lymph node dissection or adjuvant chemotherapy in high-risk patients) depends highly on the local situation, such as the operating skills of the urologist, and on the possibilities for tight follow-up. Of patients with true resistance for up-front BEP chemotherapy 90% will normally die. In patients who achieve a complete response on first-line chemotherapy, but relapse thereafter 30% will have no evidence of disease with second-line chemotherapy (VIP). In this group of patients results with high-dose chemotherapy seem promising, but its value should preferentially be determined in either a randomized fashion or by long-term follow-up from a large group of patients according to a similar protocol. The use of post-chemotherapy surgery is an essential part of management for metastatic non-seminomatous germ cell tumours, while the majority of residual masses in pure seminoma will disappear spontaneously, and frequent follow-up is recommended instead of surgical intervention.

Safety and efficacy of intraperitoneal injection of etoposide in oil suspension in mice with peritoneal carcinomatosis

We compared the safety and efficacy in mice with peritoneal carcinomatosis of two etoposide formulations: an aqueous solution (Etp-sol) and particles suspended in oil (the addition products of iodine and the ethyl esters of the fatty acids obtained from poppy-seed oil (Lipiodol) or sesame oil; Etp-oil). We also investigated tissue distribution of etoposide in rats treated with Etp-oil and Etp-sol. Etoposide was injected intraperitoneally at concentrations ranging from 52 to 392 mg/kg (increasing geometrically by a factor of 1.4). The 50% lethal dose (LD50), determined over a 2-week period of observation, was 135 mg/kg for Etp-oil and 108 mg/kg for Etp-sol. Autopsy findings included macroscopic intestinal bleeding, necrosis of the intestinal mucosa, and pulmonary congestion in mice from both treatment groups. In the efficacy trials. 10(6) P388 leukemia cells were transplanted into CDF1 male mice, and Etp-oil and Etp-sol were injected at doses of 20 mg/kg and 80 mg/kg. In the groups receiving the 20 mg/kg dose, 11 of 19 mice in the Etp-oil group survived to day 60 compared with 3 of 20 mice in the Etp-sol group. Toxicity-related deaths occurred in 1 of 20 mice treated with 80 mg/kg Etp-oil and in 8 of 20 mice treated with 80 mg/kg Etp-sol. No cancer-related deaths were associated with the 80 mg/kg dose in either treatment group. Our findings showed that the Etp-oil was associated with a lower toxicity and a higher efficacy than the Etp-sol. To evaluate tissue distribution, rats were injected intraperitoneally with 5 mg/kg body weight of Etp-sol or Etp-oil. The tissue distribution of etoposide was subsequently analyzed by high performance liquid chromatography. Compared with Etp-sol, Etp-oil delivered significantly greater amounts of etoposide and for a longer period to the omentum, taken as representative of the intraperitoneal tissue, and the etoposide concentration in blood plasma was increased more slowly and decreased more gradually.

[Therapeutic intensification and hematopoietic stem cell autotransplantation in the treatment of solid tumors in adults: principles, realization and application to the treatment of germ cell, trophoblastic, breast, ovarian and small-cell bronchial tumors. 1]

Autologous bone marrow transplantation for the treatment of solid tumors in adults remains an uncommon therapeutic approach. The feasibility of such high-dose therapies is clearly proved, especially with the advent of hematopoietic growth factors and the rescue by the peripheral stem cells to reduce the duration of the chemotherapy-induced myeloid aplasia. The question is to exactly define the place of high-dose therapy in the land of solid tumors. For the treatment of primary chemoresistant gonadal germ-cell tumors, the possibility to cure the patients and the interest of high-dose therapy with autologous bone marrow transplantation are clearly demonstrated. As consolidation for the treatment of poor prognosis tumors, the place of high-dose therapies remains moot. For the treatment of chemoresistant extragonadal germ-cell tumors, especially for primary mediastinal tumors, the level of resistance to cisplatin-based chemotherapy regimens is generally too high to be overcome by intensive therapies given as single course or as tandem courses. However in association with debulking surgery, this therapeutic approach has to be considered for some patients. In the treatment of poor prognosis breast cancer, high-dose therapy with autologous bone marrow transplantation or with peripheral stem cells support is able to convert some patients with partial response into complete responders. However, the consequences on overall survival and on disease-free survival are not evident. For metastatic breast cancer and for poor-prognosis tumors (inflammatory breast cancer, axillary metastatic nodes > or = 8), the interest of high-dose therapy has to be determined by randomized studies. These studies are ongoing in USA and in Europe. For the treatment of poor-prognosis ovarian cancer, the situation is more difficult to appraise. Once again, randomized studies have to be done to precisely define the place of high-dose therapy. In the land of small-cell lung carcinomas, high-dose therapy is actually forsaken by most of authors, even for limited diseases. The results of previous studies are disappointing. Moreover, occult medullary micrometastases involvement is frequent, once again even in limited diseases. However new therapeutic associations, as the ICE regimen (IFM, Carboplatin, VP-16) delivered as single or tandem therapy, have to be studied, especially as early consolidation therapy for the treatment of limited small-cell lung carcinomas.

Malignant germ cell tumors in childhood

The outlook for patients with germ cell tumors was poor before the advent of effective chemotherapy. In this study the outcome of multiagent chemotherapy in children treated for germ cell tumor is assessed. Between January 1984 and December 1990, 107 patients were diagnosed to have germ cell tumors. Postsurgical therapy was based on tumor site, stage, and histology. Combination chemotherapy was employed in patients with Stages I and II disease with postoperative raised tumor markers and all patients with Stages III and IV. Between 1984-1988, patients received cisplatin, vinblastin, bleomycin, and methotrexate (PVB-M), and thereafter between 1988-1990, they received bleomycin, etoposide, and cisplatin (BEP). Of 34 patients treated with PVB-M and 27 treated with BEP, the complete remission rate was 40% and 85%, respectively, and the overall survival was 30% at 5 years for PVB-M and 80% at 3 years for BEP. We conclude that etoposide with cisplatin is superior to vinblastin with cisplatin in the treatment of advanced germ cell tumors because of greater efficacy, decreased toxicity, and better compliance in children.

A phase I/II study of a stepwise dose-escalated regimen of cisplatin, etoposide and ifosfamide plus granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with advanced germ cell tumours

In order to improve the survival of patients with metastatic advanced disease germ cell tumours (according to Indiana University classification), 77 patients were treated by a stepwise dose-escalated combination regimen of platinum (P), etoposide (E) and ifosfamide (I) (PEI) followed by application of granulocyte-macrophage colony-stimulating factor (GM-CSF) (10 micrograms/kg subcutaneously per day at levels 2 and 3) starting the first day after chemotherapy for 10 consecutive days. The maximally tolerated dose was reached at the third dose level with P 30 mg/m2, E 200 mg/m2 and I 1.6 g/m2, all given for 5 days, once every 21 days, for a total of four cycles. Sixty-seven per cent of patients had three or more metastatic sites. Twenty-two per cent of patients had extragonadal primary tumours. 49 (65%) patients achieved complete remission, and 9 additional patients (12%) achieved marker normalisation with unresectable residual disease. After a median follow-up of 27 months, the overall survival is 80%, with 67% of patients remaining free from progression. The dose-limiting toxicities were WHO grades 3/4 mucositis/enteritis in 33% of patients and prolonged thrombocytopenia < 20.000/microliters (> 10 days). Adverse reactions to GM-CSF occurred in 13% of patients. The use of a single haematopoietic growth factor allowed only a moderate increase in dose intensity (factor 1.37). Peripheral blood stem cells will be additionally incorporated into the treatment protocol in order to deliver multiple cycles of an upfront dose-intensified PEI regimen in patients with "poor risk" germ cell tumours with less toxicity.

Treatment of Metastatic Testicular Tumours with Bleomycin, Etoposide, Cisplatin and Vincristine (BEPV)

Between August 1983 and December 1988, 47 patients with metastatic testicular tumours (44 non-seminomatous, three seminomas) were treated with two to six courses of bleomycin, etoposide, cisplatin and vincristine (BEPV). Five stage I tumours were included, three because of raised tumour markers following orchidectomy, one with vascular invasion of spermatic cord vessels and the other with both these features. Forty-four patients (93.6%) are alive and disease free 12–75 months (median 39 months) after completion of BEPV. Further treatment was necessary in 12 of the survivors. Eight had residual disease excised, one of whom received radiotherapy, one additional chemotherapy and one both radiotherapy and chemotherapy. Of the remaining four, two had radiotherapy and two second line chemotherapy. Thirty-one non-seminomatous and the three seminoma patients had small volume disease and all are in complete remission. Ten of the 13 patients with bulky disease are alive. It is concluded that BEPV is a well-tolerated, effective, first line therapy for patients with metastatic testicular tumour.

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.

Modified cisplatin, etoposide (or vinblastine) and ifosfamide salvage therapy for male germ-cell tumors. Long-term results

Between 1985 and 1989, 36 consecutive male patients with advanced germ-cell tumors, who had failed to be cured with either the cisplatin, vinblastine, bleomycin (PVB) or the cisplatin, etoposide, bleomycin (PEB) combinations, entered either of two modified salvage therapy regimens consisting of cisplatin, etoposide, and ifosfamide (PEI) or cisplatin, vinblastine and ifosfamide (PVI). All patients had evidence of active disease. Ifosfamide was given at the dosage of 2.5 gr/m2 (with mesna protection) on days 1 and 2; etoposide and cisplatin were given at the dosage of 100 mg/m2 and 40 mg/m2, respectively, on days 3 to 5. In the PVI schedule, vinblastine 6 mg/m2 was given on day 3. Overall, 20 (56%, C.I. 39 to 72) patients entered complete response (CR) or achieved disease-free status (NED) with post-chemotherapy surgery. After a follow-up of 2 to 7 years, 15 patients (42%, C.I. 24 to 58) remain alive and free of disease. None of the 9 patients unresponsive to the first-line therapy and/or with extragonadal primaries entered CR or achieved the NED status, versus 20 (74%, C.I. 58 to 91) of the 27 patients with primary testicular tumors who were responsive to the first-line therapy (p less than 0.001). PEI was used in 20 of these 27 patients, with excellent results (90% CR and 70% continuously NED) independently of primary therapy, PVB or PEB. By contrast, only 2 of the 7 patients treated with PVI following PEB entered CR. Toxicity was not life-threatening. Nine (25%) patients suffered granulocytopenic fever and 3 (8%) required platelet transfusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined approach (chemotherapy plus surgery) in advanced testis tumours

Eight consecutive patients with stage III or bulky stage II germ cell tumors were treated with 4 cycles of cisplatin, etoposide and bleomycin combination chemotherapy (PEB). 3 patients were in complete remission (CR) after surgery of residual masses. 5 patients received 2–4 additional courses of P.V.I. (cisplatin, vinblastine and iphosphamide) chemotherapy and had complete remission (3 cases after surgery of residual masses). No residual tumor was found in 2 cases at surgery (25%). In the present series 3 patients had extrapulmonary disease, 2 retroperitoneal lymphnodes larger than 10 cm. and pulmonary disease. 1 patient had previous incomplete RPND. After a median follow-up period of 30 months (15–37) all the patients are disease-free with normal levels of AFP and beta HCG. In conclusion we repeat that intensive combination chemotherapy is the key for successful surgery of residual malignancy in patients with disseminated testicular cancer. Second-line of chemotherapy is more favourable than early surgery, in our opinion, for treatment of far-advanced disease.

Low dose bleomycin with etoposide and cisplatin for metastatic testicular teratoma

Thirty-nine men with metastatic testicular teratoma were treated with a combination of bleomycin, etoposide and cisplatin (BEP). Unlike the usual regimen of these 3 agents, bleomycin and cisplatin were given on day 1 only of the cycle, with etoposide for 3 days. Thirty patients (77%) are alive and disease-free after a median follow-up of 31 months--24/25 (96%) with disease confined to lymph nodes but only 6/14 (43%) patients with lung involvement. Modified BEP chemotherapy is a well tolerated alternative to standard BEP chemotherapy for small volume nodal disease; it minimises in-patient time, hospital visits and the risk of bleomycin lung toxicity. However, omission of the weekly doses of bleomycin and shortening of the administration schedule of cisplatin and etoposide may be detrimental in patients with more extensive disease, for whom more intensive therapy may be necessary.

Failure of salvage treatment in metastatic testicular teratoma

From January 1978 to March 1989, 92 consecutive patients with metastatic testicular teratoma have been treated with cisplatin-based chemotherapy. Thirty seven failed to achieve a complete response, and another four subsequently relapsed. These 41 have required further treatment, consisting of surgery (16 patients), radiotherapy (n = 13) and chemotherapy (n = 12). Surgery was generally used for residual masses where tumour markers were normal, radiotherapy for masses where surgery was not possible or for palliation, and second line chemotherapy was used in patients with raised serum tumour markers or in the presence of multiple inoperable pulmonary metastases. Nine of 16 (56%) patients treated surgically are disease-free, including two who had malignant teratoma in the resection specimen. Three of 13 patients irradiated are disease-free, although two of these three had subsequent excision of residual masses. All 12 patients treated with second-line chemotherapy have died. Surgical excision of residual masses appears to be the most effective way of rendering patients disease-free, providing serum tumour markers are normal. Most of these residual masses will consist of differentiated teratoma or necrosis, but it may be possible to salvage patients with residual malignant disease, providing complete clearance can be achieved. Incompletely resected malignant disease carries a poor prognosis, and incompletely resected disease that is histologically benign will run the risk of subsequent relapse. Radiotherapy provides good palliation but is much less effective than surgery as treatment for residual masses, and should only be used if complete excision cannot be accomplished.(ABSTRACT TRUNCATED AT 250 WORDS)

Etoposide therapy for testicular cancer

During the past two decades, dramatic strides have been made in the treatment of metastatic testicular cancer. In the early 1970s, cisplatin, vinblastine, and bleomycin (PVB) produced durable complete remissions (CR) in approximately 70% of treated patients. In the early 1980s, etoposide emerged as the only drug with single-agent activity in cisplatin-refractory patients. Based on preclinical data demonstrating synergy of cisplatin plus etoposide, the two-drug combination proved to be a useful salvage therapy, curing approximately 25% of such patients. Further evaluation of etoposide as part of initial therapy by the Southeastern Cancer Study Group (SECSG) compared PVB with bleomycin, etoposide, and cisplatin (BEP) in previously untreated patients with metastatic germ cell tumors. Not only did BEP have significantly less toxicity, it proved to be superior to PBV in patients with advanced disease. Varying the dose and schedule of etoposide also may provide patients with potentially useful avenues of treatment. High-dose etoposide plus carboplatin in drug-refractory patients has produced durable CR in a cohort of treated patients; it is currently being evaluated as part of initial salvage therapy. The schedule dependency of etoposide in small cell lung cancer led us to evaluate daily oral administration of etoposide in patients refractory to previous etoposide therapy; objective response rates of approximately 15% to 25% were observed. In summary, etoposide remains an integral part of the treatment regimen for testis cancer. However, the incorporation of innovative dose and schedule combinations for etoposide may further improve its therapeutic index for this disease.

Chemotherapy with maximally tolerable doses of VP 16-213 and cyclophosphamide followed by autologous bone marrow transplantation for the treatment of relapsed or refractory germ cell tumors

Eleven patients with advanced nonseminomatous germ cell tumors (NSGCT), who relapsed after or were refractory to standard dose cisplatin-based remission induction chemotherapy, were treated in a phase II clinical trial with VP 16-213 2500 mg/m2 and cyclophosphamide 7 g/m2. Both drugs were given in maximally tolerable doses regarding extramedullary toxicity. Urothelial damage due to cyclophosphamide was prevented by the administration of mesnum. Autologous bone marrow was infused on day 7 to prevent long lasting medullary toxicity. Because of the disappointing results in the first three patients, a second treatment step was added. The next eight patients were treated with 2500 mg/m2 VP 16-213 divided and given on days 1-2-3 and after full bone marrow recovery with total doses of VP 16-213 2000 mg/m2 plus cyclophosphamide 7 g/m2 divided and given on days 29-30-31, followed by autologous bone marrow transplantation (ABMT) on day 35. Toxicity to high-dose VP 16-213 plus cyclophosphamide followed by ABMT consisted of mucositis, nausea, vomiting and diarrhea. No cardiac toxicity or hemorrhagic cystitis occurred. The mean duration of leukopenia and thrombopenia was 14 and 13 days respectively. The additional, preceding treatment with VP 16-213 as a single agent caused mucositis, and leukopenia and thrombopenia for a mean number of 9 and 6 days respectively. Seven responses were obtained: two complete responses of 46 and 66+ weeks respectively and five partial responses with a median response duration of 12 weeks. The median survival time was 40 weeks. This regimen of one or two courses with maximally tolerable doses of VP 16-213 plus cyclophosphamide and ABMT is not sufficient to salvage a substantial number of patients with relapsing or refractory NSGCT.

Growth and chemotherapy of a human germ-cell tumour line (GCT 27)

The human germ-cell tumour cell line GCT 27 growing as subcutaneous xenograft tumours in male nude mice was used in the 4th and 5th passage to study chemotherapeutic drug responses. Recipient mice received 5 Gy whole body irradiation immediately before tumour transplantation. The median take rate was 62% (range 39-73%) and the median volume doubling time 14 days (range 7-28 days). For bleomycin, cisplatin and carboplatin a clear dose response for growth delay was observed. Bleomycin caused substantial weight loss at doses above 75 mg/kg whereas good response to cisplatin was obtained without serious toxic effects. Vinblastine and etoposide exerted no effect when given in non-toxic doses. The response to etoposide was not improved either by fractionated treatment or by combination with verapamil. However, the combination of 20 mg/kg etoposide and 2 mg/kg cisplatin, which when given alone were ineffective, led to a growth delay that was equal to that observed following the administration of higher cisplatin doses. This effect may be explained by the fact that etoposide, as an inhibitor of DNA-topoisomerase II, may interfere with the repair of DNA interstrand cross-links caused by cisplatin.

Treatment of disseminated germ-cell tumors with cisplatin, bleomycin, and either vinblastine or etoposide

Standard chemotherapy for disseminated germ-cell tumors includes a combination of cisplatin, vinblastine, and bleomycin, but this regimen produces substantial neuromuscular toxicity. In a randomized clinical trial in 261 men with disseminated germ-cell tumors, we substituted etoposide for the vinblastine in this regimen in half the patients to compare the efficacy and toxicity of the two treatments. Among 244 patients who could be evaluated for a response, 74 percent of those receiving the regimen including vinblastine and 83 percent of those receiving the regimen including etoposide became disease-free with or without subsequent surgery (P not significant). Among the 157 patients with high tumor volume, 61 percent became disease-free on the regimen that included vinblastine, as compared with 77 percent on the regimen that included etoposide (P less than 0.05). Survival among the patients who received etoposide was higher (P = 0.048). The regimens were similar in terms of myelosuppressive effects and pulmonary toxicity. However, the etoposide regimen caused substantially fewer paresthesias (P = 0.02), abdominal cramps (P = 0.0008), and myalgias (P = 0.00002). We conclude that etoposide with cisplatin and bleomycin is superior to vinblastine with cisplatin and bleomycin in the treatment of disseminated germ-cell tumors because of diminished neuromuscular toxicity and, among patients with advanced disease, better efficacy.

Changes in testicular cancer in Scotland

There are two purposes to this paper. Firstly to describe the temporal pattern of germ-cell testicular cancers in Scotland, both as a single entity and as the histological sub-types (pure) seminoma and teratoma. Incidence rates rose by over 50% between 1959 and 1984, with the rates of seminoma increasing only marginally and the majority of the overall increase accounted for by the substantial increase observed among the sub-type teratoma. Secondly, to investigate the impact of new therapies on the mortality rate from germ-cell testicular cancer in Scotland in the light of improvements in survival rate reported during the last 25 years from clinical trials and clinical series. Noticeable changes have occurred in the temporal pattern of mortality which cannot be explained by changes in incidence. The ever-widening gap between the increasing incidence rate and the declining mortality rate, particularly apparent in the high-risk age group 15-44, indicates an improving prognosis for patients with this malignancy in Scotland.

Application of an in vitro antimetabolic assay to human germ cell testicular tumors for the preclinical evaluation of drug sensitivity

An in vitro assay, which evaluates the effect of drugs on labeled nucleotide precursor incorporation 3H-thymidine and 3H-uridine after 3 hours of in vitro treatment, was applied to human germ cell testicular tumors. The assay was feasible on 78% of the 259 tumors, and the results were evaluable in 95% of these, which shows the good potential of its clinical application. In vitro response rates to conventional agents were comparable to clinical response rates reported in the literature for monochemotherapy regimens, thus demonstrating the accuracy of the assay in reproducing the sensitivity of the tumor type. The specificity of the assay in predicting drug sensitivity of individual tumors was investigated on 28 lesions from 24 patients who had residual disease after surgery. A significant correlation was found between in vitro and clinical sensitivity to the same drugs (P = 0.026), with an overall agreement of 92% when tumor metastases were tested in vitro. In contrast, no significant correlation, and a poor agreement (62%) was found when the primary tumor was tested.

Treatment of persistent or relapsing advanced germ cell neoplasms with cisplatin, etoposide and bleomycin

Twenty-six patients, previously treated with cisplatin, vinblastine and bleomycin (pVB) had residual or recurrent germ cell tumors and were treated with cisplatin, etoposide and bleomycin (peB). Six patients obtained complete response and 11 patients partial response. Of the 11 patients with partial response 5 were disease free after post-chemotherapy surgery. Seven patients are still alive without evidence of disease with a median follow-up of 40 months (range 14+ - 57+ months). One patient died from acute non-lymphocytic leukemia without evidence of germ cell cancer. Toxicity was modest with only three patients having leukopenic fever. Retrospectively, the patients were analyzed in two groups according to their initial prognostic features. Thirteen patients were considered to have unfavourable prognostic factors and all had progress/relapse after treatment with peB. It is concluded that peB might be useful as first line therapy because of modest toxicity and considerable activity in pretreated patients and that more intensive therapy is necessary in patients with unfavourable prognostic features.

Clinical pharmacology of intracarotid etoposide

Pharmacokinetics studies were performed in ten patients who received VP-16 by intracarotid infusion at 100-300 mg/m2. VP-16 was analyzed by high-pressure liquid chromatography. ESTRIP and NONLIN were used to characterize VP-16 pharmacokinetics. VP-16 disappeared biphasically, with a t1/2 beta of 6.1 +/- 1.4 h; the total clearance was 26.8 +/- 2.8 ml/min/m2, and the Vss was 8.8 +/- 1.6 l/m2. The pharmacokinetics was not significantly different after administration by the IV route. However, at a lower dosage, less than 140 mg/m2, the half-life appears to be shorter. This may or may not be significant, since VP-16 pharmacokinetics is quite variable and the number of patients studied is relatively small. Overall, the brain and brain tumor do not appear to have any first-pass effect on VP-16 pharmacokinetics.

Chemotherapy with adriamycin and vincristine alternated with cyclophosphamide and actinomycin D in testicular germ cell tumors refractory to cisplatin, vinblastine and bleomycin

Eighteen patients with testicular cancer refractory to cisplatin, vinblastine and bleomycin (PVB) were treated with a non-cross-resistant regimen including adriamycin, 60 mg/m2 i.v. on day 1, and vincristine, 1.2 mg/m2 i.v. on days 1 and 8, alternated q 3 weeks with cyclophosphamide, 600 mg/m2 i.v. on days 1 and 8, and actinomycin D, 1 mg/m2 i.v. on days 1 and 8. The median number of administered cycles was 8 (range 3-14). The results were analyzed according to previous response to PVB. One of two patients relapsing after the first-line therapy obtained a transient second complete response (CR) (duration 7 months). None of seven patients who showed no response to PVB obtained a CR; in 3/9 patients with a partial response (PR) after PVB, the achievement of CR could not be definitely attributed to salvage therapy. Toxicity was mild; no cardiac failure or drug-related deaths were observed. In conclusion, these two alternating regimens were well tolerated, but this treatment was not found to be useful in patients not responsive to PVB, for whom new and alternative therapies are required. The favorable impact on prognosis, evident only in the subgroup of patients with PR, was probably attributable to PVB rather than to this salvage regimen.

VP 16 plus ifosfamide plus cisplatin as salvage therapy in refractory testicular cancer

In patients with refractory germ cell tumour who fail to achieve complete remission (CR) or which achieve CR but subsequently experience disease progression within 2 months of receiving cisplatin + vinblastine + bleomycin (PVB) the results of further treatment are poor. Similarly, third-line therapy after cisplatin with VP 16 salvage rarely produces clinically significant remission. From February 1983 to October 1984 we treated 53 patients with ifosfamide (1.2 g/m2 per day on days 1-5), VP 16 (75 mg/m2 per day on days 1-5), cisplatin (20 mg/m2 per day on days 1-5), and N-acetylcysteine (2.0 g p.o. every 6 h on days 1-7). This was repeated every 21 days for four to six cycles. One group of patients (group A, 20 pts) had achieved partial remission (PR) but still had nonresectable tumours after PVB therapy; a further group (group B, 4 pts) had achieved CR with PVB but then experienced disease progression within 2 months; the remaining patients (group C, 28 pts) had experienced disease progression after one or more salvage attempts, including therapy with cisplatin and VP 16. Of the original 53 patients, 51 were evaluable for response. Toxicity included moderate to severe myelosuppression in almost all patients, fever/sepsis in 8, creatinine greater than or equal to 6 mg% in 4, and hematuria in 4 patients. There were no drug-related deaths. CR was attained in 17/51 patients (34%), these being 8/20 in group A, 1/4 in group B, and 8/28 in group C, and 10 patients have remained in CR for periods ranging from over 1 month to over 17 months. PR was achieved in 20 patients (40%), but their median duration of remission was only 2 months. We feel these results, obtained in a poor-prognosis patient population, are sufficiently encouraging to warrant further study of this regimen, including investigation of its use as initial salvage therapy following PVB.

Cisplatin, etoposide, bleomycin first-line therapy and early resection of residual tumor in far-advanced germinal testis cancer

Forty consecutive patients with far-advanced germinal testis tumors (lymph node metastases greater than 10 cm, pulmonary nodules greater than 5 cm, extrapulmonary spread, alpha-fetoprotein greater than 1000 ng/ml, human chorionic gonadotropin greater than 50,000 mIU/ml) were treated with five courses of cisplatin, etoposide, and bleomycin (PEB). Twenty-five patients underwent surgery for the removal of residual masses after the first three inductions. Fibrotic-necrotic tissue was resected in 11 cases, 12 had mature teratoma, and residual cancer was found in 2. After the combined-modality treatment, 37 patients (82.5%) entered complete remission (CR): 25 (62.5%) with PEB and 12 (30%) with PEB and complete removal of the residual tumor. One patient progressed on therapy, and two others had incomplete resection of the residual disease. Hematologic toxicity was moderate and gastrointestinal toxicity was very mild. After a median follow-up period of 24 months (range, 13-40), 33 patients (82.5%) remain continuously disease-free, and 4 experienced relapse. Only one of these was salvaged with further surgery and chemotherapy. First-line PEB therapy combined with early resection of residual tumor induced a very high continuous CR rate in patients with far-advanced germinal testis cancer, and toxicity was moderate.

Cisplatin and etoposide salvage therapy and resection of the residual tumor in pretreated germ cell testicular cancer

Thirty-two consecutive patients with pretreated germinal testis cancer received three to four inductions of cisplatin and etoposide therapy (PE). Patients not pretreated, or only partially pretreated with bleomycin (B), also received this drug for a maximum of 12 doses. Sixteen patients underwent secondary surgery for the removal of residual masses. Twelve (37.5%) entered complete remission (CR) with chemotherapy alone, and an additional 9 cases (28%) were rendered tumor-free by surgery. The 21 disease-free patients (65.5%) received two further inductions and no maintenance. Toxicity was moderate, and 1 of the 16 patients who underwent surgery died postoperatively of pulmonary embolism. After a median follow-up period of 26 months (range, 9-60), 2 patients have died in CR and 15 (47%) are currently alive and have been continuously disease-free. The major determinant of tumor response was prior therapy. Eleven of 14 (78%) patients who were not pretreated with cisplatin achieved a continuous disease-free status versus only 4 of the 18 pretreated patients (22%, P less than 0.01). In this set of cases, complete responders to prior PVB therapy did better than incomplete responders treated for tumor progression. It can be concluded that normal-dose PE +/- B therapy, followed by surgical resection of the residual tumor, is a satisfactory salvage therapy in patients not pretreated with cisplatin and is also active in complete responders to prior PVB therapy.

Cisplatin combination chemotherapy for advanced germ-cell testicular tumours

Thirty-six patients with advanced non-seminomatous germ-cell testicular tumours and two patients with advanced seminomas were treated with cisplatin-containing combination chemotherapy. Thirty-four patients received cisplatin 100 mg/m2 iv, vinblastine 0.3 mg/kg iv and bleomycin 30 mg iv (PVB) and three patients received this combination with etoposide (VP16-213) 120 mg/m2 iv on 3 consecutive days substituted for vinblastine (BEP). One patient received cisplatin and bleomycin only. All 35 evaluable patients with non-seminomatous tumours responded; 22 patients (61%) achieved a complete response (CR); 16 of these (73%) are alive with no evidence of disease at follow-up ranging from 18 to 55 months (median 36). Of 13 patients achieving a partial response (PR), 11 have died of progressive disease at 7 to 30 months (median 11) and two are alive with disease which has continued to regress following chemotherapy. Of 32 patients who received adequate chemotherapy, 16 (50%) are alive and disease-free and three (9%) are alive with evidence of disease. The chances of achieving a CR were reduced in those patients with bulky disease or high levels of AFP or beta hCG at presentation but not in those who had received prior radiotherapy. Toxicity was considerable, including alopecia and nausea or vomiting in all patients, and haematological toxicity, neurotoxicity, hearing loss and dyspnoea in a substantial number of patients.

EORTC Genito-Urinary Group studies in advanced testicular cancer--past and future

Two hundred and twenty-eight patients with advanced testicular cancer were entered into a randomized study of chemotherapy comprising cis-platinum (P) 20 mg/m2-, days 1-5 every 3 weeks for four courses, bleomycin (B) 30 mg weekly for 12 weeks, and vinblastine (V) at either the low dose of 0.15 mg/kg or the high dose of 0.20 mg/kg on days 1 and 2 every 3 weeks for four courses. In this interim analysis, 64 patients were randomized to high dose PVB. Forty-five (71%) achieved a complete response, and 13 (25%) a partial response. Seventy patients received low dose PVB of whom 50 (71%) achieved a complete response and 16 (23%) a partial response. Thus there is no difference in the efficacy of this combination chemotherapy with respect to the dose of vinblastine, but the low dose schedule was less toxic (particularly to bone marrow). It was also apparent that the response rate varied with the volume of metastatic disease, irrespective of the dose of vinblastine. Patients with low volume metastases had a complete response rate (CR) of 88%, while those with high volume had a CR rate of 60%. In a second randomization, 68 patients achieving CR were randomized to receive either 1 year of further (maintenance) chemotherapy with cis-platinum and vinblastine, or no further chemotherapy. One of 37 patients (3%) receiving treatment and 2 of 31 patients (6%) not receiving treatment relapsed, with a follow-up of at least 10 months. Thus maintenance chemotherapy appears not to be necessary in the treatment of advanced testicular cancer.

Role of etoposide-based chemotherapy in the treatment of patients with refractory or relapsing germ cell tumors

Forty-nine patients with metastatic germ cell tumors were treated with etoposide 100 mg/m2 and cisplatin 20 mg/m2 intravenously each day for five days as "salvage" chemotherapy. Forty-seven patients had received standard induction regimens for metastatic germ cell tumors before receiving etoposide and cisplatin. Four patients were treated after surgical resection of a single site of relapse (Group I). Forty-five patients had measurable or evaluable disease at the time of treatment. In 17 patients with evaluable disease who had either achieved a prior complete remission or received no prior cisplatin (Group II), eight (47 percent) complete and four (24 percent) partial remission were observed. In 28 patients who had never achieved a prior complete remission (Group III), no complete and five (18 percent) partial responses were observed. Seven of 21 patients in Groups I and II and none of 28 patients in Group III remain alive and free of disease. Assuming prior treatment with cisplatin-based chemotherapy, these data and a review of the published experience with similar salvage regimens for patients with relapsing or refractory germ cell tumors suggest that combination chemotherapy based on etoposide and cisplatin is effective primarily in those patients who achieved a prior complete remission. Such therapy is ineffective in the absence of a prior complete remission probably because the patients have tumors that are largely resistant to cisplatin. Observed responses are probably due to etoposide alone. Investigational therapies should be pursued in those patients whose disease is refractory to current induction regimens.

Five-year survival of patients with disseminated nonseminomatous testicular cancer treated with cisplatin, vinblastine, and bleomycin

Ninety-one patients with disseminated testicular non-seminomas were treated with 3 to 4 cycles of cisplatin, vinblastine, and bleomycin (PVB) induction chemotherapy followed by cisplatin and vinblastine maintenance therapy for 1 year. The follow-up of these patients ranges from 24 to 66 months. Forty-nine (54%) patients achieved complete remission by chemotherapy alone and 14 (15%) were rendered free of tumor by surgery after chemotherapy, for a total complete remission rate of 69%. Three complete responders relapsed within 13 months, and two died. One additional complete responder died of a noncancer-related cause. One of the surgical complete responders relapsed and died. Overall, 58 (64%) patients remain free of disease. The 5-year survival is 95% for complete responders, 32% for partial responders, and 72% overall. This combination regimen has significantly improved the survival of disseminated testicular cancer patients, equaling that of Stage II patients in older literature.

Etoposide: a semisynthetic epipodophyllotoxin. Chemistry, pharmacology, pharmacokinetics, adverse effects and use as an antineoplastic agent

Etoposide (VP 16) is a semi-synthetic derivative of 4'- demethylepipodophyllotoxin , a naturally occurring compound synthesized by the North American May apple (Podophyllum peltatum ) and the Indian species Podophyllum emodi Wallich . Although podophyllotoxins are classical spindle poisons causing inhibition of mitosis by blocking mitrotubular assembly, etoposide inhibits cell cycle progression at a premitotic phase (late S and G2), probably via inhibition of DNA synthesis. There appears to be a selective antileukemic dose response relationship when compared to normal hematopoietic elements. Etoposide is effective when administered orally at about twice the recommended parenteral dosage. Schedule dependency in both animal models and clinical trials has been observed; multiple dosing over three to five consecutive days is superior to weekly single dose administration. Etoposide's dose-limiting toxicity is myelosuppression (leukopenia), which is quite predictable; alopecia and Gl toxicity (nausea, vomiting, stomatitis) occur in about 20-30% of patients given recommended dosages. Etoposide appears to be one of the most active drugs for small cell lung cancer, testicular carcinoma (the Food and Drug Administration approved indication), ANLL and malignant lymphoma. Etoposide also has demonstrated activity in refractory pediatric neoplasms, hepatocellular, esophageal, gastric and prostatic carcinoma, ovarian cancer, chronic and acute leukemias and non-small cell lung cancer, although additional single and combination drug studies are needed to substantiate these data. Its contribution in front-line combination chemotherapeutic regimens for these cancers will be better defined in the forthcoming years. Etoposide appears to have minimal activity in breast cancer and, based on current data, it is inactive against malignant melanoma, colorectal adenocarcinoma and cancer of the head and neck, although the dosage and schedules used in many of the Phase II studies may have been suboptimal.

Ifosfamide in combination chemotherapy for sarcomas and testicular carcinomas

The efficacy of ifosfamide combination chemotherapy was studied in 164 patients, 94 with advanced testicular carcinoma and 70 with metastatic sarcoma. Ifosfamide was given at 40-60 mg/kg/day i.v. on five consecutive days every 3-4 weeks together with mesna prophylaxis with 8 mg/kg i.v. being used at 0, 4 and 8 h after ifosfamide administration. Of 70 sarcoma patients 57 were evaluable for response, of whom 49 had received prior chemotherapy. The overall response rate was 46% (26/57) including 3 complete (CR) and 14 partial remissions (PR). Ninety-four patients with germ cell tumours of the testis were treated. Of 16 seminoma patients 15 achieved CR or PR. Seventy-eight patients with nonseminomatous testicular cancer who had received previous chemotherapy were either treated with ifosfamide/etoposide (n = 63, remission rate: 30%) or ifosfamide/cisplatin (n = 15, CR + PR: 33%). These results indicate that ifosfamide alone or in combination is active in sarcomas, seminomas and teratomas and that further studies are warranted employing the drug in first-line regimens.