Effective treatment of hormonally-unresponsive metastatic carcinoma of the prostate with adriamycin and cyclophosphamide: methods of documenting tumor response and progression

Elevated serum CEA is associated with liver metastasis and distinctive circulating tumor DNA alterations in patients with castration-resistant prostate cancer

BACKGROUND

Elevated serum carcinoembryonic antigen (CEA) is used to identify "treatment emergent" forms of castration-resistant prostate cancer (CRPC) such as aggressive variant prostate cancer (AVPC). However, its individual utility as a prognostic marker and the genetic alterations associated with its expression have not been extensively studied in CRPC.

METHODS

This study retrospectively analyzed clinical outcomes and circulating tumor DNA profiles in 163 patients with CRPC and elevated or normal serum CEA. These same patients were then classified as AVPC or non-AVPC and compared to determine the uniqueness of CEA-associated gene alterations.

RESULTS

Patients with elevated CEA demonstrated higher rates of liver metastasis (37.5% vs. 19.1%, p = 0.02) and decreased median overall survival from CRPC diagnosis (28.7 vs. 73.2 mo, p < 0.0001). In addition, patients with elevated CEA were more likely to harbor copy number amplifications (CNAs) in AR, PIK3CA, MYC, BRAF, CDK6, MET, CCNE1, KIT, RAF1, and KRAS. Based on variant allele frequency we also defined "clonal" single-nucleotide variants (SNVs) thought to be driving disease progression in each patient and found that CEA expression was negatively correlated with clonal AR SNVs and positively correlated with clonal TP53 SNVs. Of these genetic associations, only the increases in clonal TP53 SNVs and KRAS amplifications were recapitulated among patients with AVPC when compared to patients without AVPC.

CONCLUSIONS

Together these findings suggest that CEA expression in CRPC is associated with aggressive clinical behavior and gene alterations distinct from those in AVPC.

Platinum-based chemotherapy for variant castrate-resistant prostate cancer

PURPOSE

Clinical features characteristic of small-cell prostate carcinoma (SCPC), "anaplastic," often emerge during the progression of prostate cancer. We sought to determine the efficacy of platinum-based chemotherapy in patients meeting at least one of seven prospectively defined "anaplastic" clinical criteria, including exclusive visceral or predominantly lytic bone metastases, bulky tumor masses, low prostate-specific antigen levels relative to tumor burden, or short response to androgen deprivation therapy.

EXPERIMENTAL DESIGN

A 120-patient phase II trial of first-line carboplatin and docetaxel (CD) and second-line etoposide and cisplatin (EP) was designed to provide reliable clinical response estimates under a Bayesian probability model with early stopping rules in place for futility and toxicity.

RESULTS

Seventy-four of 113 (65.4%) and 24 of 71 (33.8%) were progression free after four cycles of CD and EP, respectively. Median overall survival (OS) was 16 months [95% confidence interval (CI), 13.6-19.0 months]. Of the seven "anaplastic" criteria, bulky tumor mass was significantly associated with poor outcome. Lactic acid dehydrogenase strongly predicted for OS and rapid progression. Serum carcinoembryonic antigen (CEA) concentration strongly predicted OS but not rapid progression. Neuroendocrine markers did not predict outcome or response to therapy.

CONCLUSION

Our findings support the hypothesis that patients with "anaplastic" prostate cancer are a recognizable subset characterized by a high response rate of short duration to platinum-containing chemotherapies, similar to SCPC. Our results suggest that CEA is useful for selecting therapy in men with castration-resistant prostate cancer and consolidative therapies to bulky high-grade tumor masses should be considered in this patient population.

The role of doxorubicin and epirubicin in the treatment of patients with metastatic hormone-refractory prostate cancer

Advanced hormone-refractory prostate cancer (HRPC) is characterized by prevalently osteoblastic bone metastases which are what mostly affect these patients' quality of life and make the assessment of response to treatment particularly difficult by commonly used criteria. HRPC cannot be cured by any available therapeutic option, and chemotherapy has to be still considered as a palliative treatment. The anthracyclines doxorubicin (Dox) and epirubicin (Epi), alone or in combination with other agents, have been extensively used in the treatment of HRPC, but controversial results have been reported. The majority of reviewed studies reported a pain reduction in >50% of patients receiving Dox or Epi, suggesting a substantial palliative effect by their use in metastatic HRPC. The weekly schedule of anthracyclines seemed to achieve similar results to the 3-weekly schedule but with a better toxicity profile. Although the toxic adverse effects were usually manageable when anthracyclines were combined with other agents, toxicity was severe by a number of aggressive regimens. Docetaxel is today approved for the treatment of HRPC, and must be considered the standard platform on which new agents may be combined. Given that HRPC includes a heterogeneous group of patients with variable rates of tumour growth, the combination of docetaxel with active agents such as anthracyclines may deserve further clinical investigation.

Phase II pilot study of combined chemohormonal therapy with doxorubicin and estramustine in metastatic prostate cancer

Twenty-nine patients with progressive hormone-refractory metastatic adenocarcinoma of the prostate were treated with daily estramustine phosphate at 10 mg/kg, and I.V. doxorubicin 50 mg/m2 every 3 weeks. Twenty-six patients were evaluable. Four of seven patients with nonosseous measurable disease had partial responses lasting 3 to 10 months. Eleven of 19 patients with osseous metastases had stable disease or improvement on bone scan, 6 of these for 7 months or longer. Median time to progression was 20 weeks, and the median survival was 43 weeks.

Combination of epirubicin and cisplatin in hormone-refractory metastatic prostate cancer

Anthracyclines and cisplatin have been shown separately to have modest activity in prostate cancer. The synergism between anthracyclines and cisplatin, with the lack of overlapping toxicities, led to the conduct of this phase II trial of the combination of epirubicin and cisplatin in hormone-refractory metastatic prostate cancer. Twenty-one evaluable patients with hormone-refractory metastatic prostate cancer received epirubicin 100 mg/m2 followed by cisplatin 80 mg/m2 with prehydration and mannitol diuresis. Epirubicin and cisplatin produced a biochemical response (>50% decrease in tumor marker) in 32% of patients, symptomatic improvement in 38%, and a response in measurable and evaluable disease sites in 14%. Toxicities were mainly hematologic, with 77% and 41% >grade 2 neutropenia and thrombocytopenia, respectively. Greater than grade 2 toxicities were: cardiac (three), renal secondary to sepsis (one), nausea and vomiting (two), weakness (one), mucositis (one), and diarrhea (one). The combination of epirubicin and cisplatin was associated with manageable toxicities in this elderly population; however, antitumor activity was marginal in this disease. Participation in clinical trials should continue to be offered to patients with hormone-refractory metastatic prostate cancer.

Prognostic significance of extent of disease in bone in patients with androgen-independent prostate cancer

PURPOSE

To evaluate the prognostic significance of a bone scan index (BSI) based on the weighted proportion of tumor involvement in individual bones, in relation to other factors and to survival in patients with androgen-independent prostate cancer.

PATIENTS AND METHODS

Baseline radionuclide bone scans were reviewed in 191 assessable patients with androgen-independent disease who were enrolled onto an open, randomized trial of liarozole versus prednisone. The extent of skeletal involvement was assessed by scoring each scan using the BSI and independently according to the number of metastatic lesions. The relationship of the scored bone involvement to other known prognostic factors was explored in single- and multiple-variable analyses.

RESULTS

In single-variable analyses, the pretreatment factors found to be associated with survival were age (P = .0446), performance status (P = .0005), baseline prostate-specific antigen (P = .0001), hemoglobin (P = .0001), alkaline phosphatase (P = .0002), AST (P = .0021), lactate dehydrogenase (P = .0001), and treatment (P = .0098). The extent of osseous disease was significant using both the BSI (P = .0001) and the number of lesions present (P = .0001). In multiple-variable proportional hazards analyses, only BSI, age, hemoglobin, lactate dehydrogenase, and treatment arm were associated with survival. When the patient population was divided into three equal groups, with BSI values of < 1.4%, 1.4% to 5.1%, and > 5.1%, median survivals of 18.3, 15.5, and 8.1 months, respectively, were observed (P = .0079).

CONCLUSION

The BSI quantifies the extent of skeletal involvement by tumor. It allows the identification of patients with distinct prognoses for stratification in clinical trials. Further study is needed to assess the utility of serial BSI determinations in monitoring treatment effects. The BSI may be particularly useful in the evaluation of agents for which prostate-specific antigen changes do not reflect clinical outcomes accurately.

Immunomodulatory effect of cyclophosphamide on host humoral immunity in Dunning's R-3327 adenocarcinoma of the prostate

The object of the present investigations was delineation of the exclusive effects of cyclophosphamide (Cytoxan) on host humoral response to tumor, as evaluated by the level of circulating antigen/antibody complexes (AACs), which may reflect the chemo-responsiveness of hosts and provide a rationale for new therapeutic strategies. Our data, recorded in Copenhagen X Fischer rats bearing Dunning's R-3327 Mat Ly-Lu adenocarcinoma of the prostate, show no modulatory effect of cyclophosphamide at 10 mg/kg, a nonspecific immunosuppressive effect at 30 mg/kg, and a definite immunostimulatory effect on host humoral immunity at 100 mg/kg. Sequential determination of AAC levels at different stages of tumor growth, i.e. from the primary to the metastatic stage, performed with the original purpose of demonstrating that any disturbance in the immunoregulatory mechanism of the host was due to cyclophosphamide rather than to changes in tumor load, revealed that levels of AACs parallel disease progression in the initial stages of primary tumor growth but rapidly decrease to near-normal levels in the presence of heavy tumor burden.

Update in the management of prostate cancer

Prostate cancer remains one of the commonest malignancies in our community, and it appears that its incidence is rising because of the increasing proportion of the aged population. Improved technology, including the development of new tumour markers and tumour imaging techniques, and a gradually increasing community awareness of this disease, may allow earlier diagnosis. In turn, as the proportion of patients presenting with early stage disease increases, improved approaches to the treatment of localized cancer may thus yield increased community cure rates. The mainstay of treatment of advanced disease remains hormonal manipulation. The introduction of the LHRH agonists has provided an alternative to surgical castration, but has not resulted in an improved response rate or survival from first-line therapy. We believe that these agents do not offer a major benefit, when compared with the simple procedure of orchidectomy, notwithstanding the psychological sequelae of castration. With a median survival of less than five years after hormonal manipulation, many patients still require salvage treatment after relapse. New hormonal therapies yield objective and subjective response rates of approximately 15% and 30%, respectively, but the median survival from the time of hormonal failure remains less than one year. Cytotoxic chemotherapy has not provided a panacea, but has shown definite evidence of antitumour activity in this disease. The use of relatively non-toxic single cytotoxic drugs can provide effective palliation of symptoms in up to 40% of patients and may even prolong survival in some patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone metastases: pathogenesis, treatment, and rationale for use of resorption inhibitors

Tumors in bone are usually metastatic, with breast, prostate, and lung tumors accounting for more than 80 percent of clinically manifest lesions. Untreated, such metastases can produce the symptoms that most concern cancer patients--pain, pathologic fractures, and paralysis through epidural cord compression. Recent advances in the understanding of the metastatic cascade and the regulation of bone formation and resorption provide unique therapeutic approaches for prevention and treatment of these lesions. This article reviews the prevalence, distribution, diagnosis, and treatment of metastatic cancer in the skeleton, as well as the processes involved in the development of such metastases, the local mediators responsible for some of the destructive changes in bone, and their pathologic results. In addition to considering some of the conventional therapeutic approaches, a rationale for the use of bone resorption inhibitors, such as the diphosphonates (bisphosphonates), is presented for the prevention and amelioration of the pathologic consequences of skeletal metastases.

Creatine kinase and lactate dehydrogenase isoenzymes in stage D prostatic carcinoma

Serum creatine kinase (CK) and lactate dehydrogenase (LD) isoenzymes were determined electrophoretically, along with various other biochemical markers of malignancy, in 19 patients with metastatic carcinoma of the prostate. Mitochondrial CK appeared in 15 patients, the CK-BB isoenzyme in 6. As a result, CK activity not inhibited by anti-M-subunit antibodies, CK non-M, was above the reference value in altogether 17 patients. There was a cathodic shift among the LD isoenzymes, significantly more prominent with increasing total LD, and a positive correlation between elevations of CK non-M and LD-5, suggesting a relation to tumour burden for both. An LD 'flip' (LD-1 greater than LD-2) was present in 10/15 patients. The frequency of CK non-M elevations was similar to--but not quantitatively correlated with--elevations of prostatic acid phosphatase and alkaline phosphatase. Thus, changes in CK and LD patterns are frequent in patients with prostatic cancer and must be taken into consideration when acute cardiac symptoms are evaluated in such patients.

Computed tomography of the abdomen and pelvis: documentation of tumor response and progression in disseminated prostate cancer

Computed tomography of the abdomen and pelvis has been used to stage early prostatic cancer. We investigated its value in monitoring tumor response in more advanced disease. Serial computed tomography of the abdomen and pelvis was obtained along with multiple other staging tests prior to treatment and at 3- to 4-month intervals thereafter in 32 patients with stage D2 tumor treated initially with combination chemotherapy and with hormones at progression. Pretreatment lymphography with follow-up abdominal films was also performed. Initial computed tomography of the abdomen and pelvis showed evidence of node metastases in 35% of patients while lymphography was positive in 54%. Among 19 patients with tumor response and 25 with progression, the results of treatment were objectively documented by improvement or worsening, respectively, in a mean of 5.1 and 5.0 other staging tests, exclusive of computed tomography. Computed tomography of the abdomen and pelvis improved in 85% of responding patients examined. Progression was confirmed by worsening of computed tomography in 32%. Although lymphography was often abnormal prior to treatment, in our hands it was not useful in serial monitoring of tumor status. We conclude that serial computed tomography of the abdomen and pelvis, when initially positive, is a useful test to document objectively tumor response and progression in disseminated prostatic cancer.

Phase II trial of doxorubicin in bidimensionally measurable prostatic adenocarcinoma

Intravenous doxorubicin (30 to 60 mg. per m.2 every 3 weeks) was administered to 52 patients with metastatic adenocarcinoma of the prostate, including 41 with bidimensionally measurable soft tissue lesions. Prior therapy in the measurable disease group included hormonal manipulation in 39 cases, irradiation in 39 and cytotoxic drugs in 19. In 39 of 41 adequately treated patients with soft tissue lesions only 2 (5 per cent, 95 per cent confidence limits 0 to 12 per cent) achieved a partial remission for 12 and 6 months, respectively, 3 had a minor response for 5, 4 and 3 months, respectively, and 1 had stabilization of disease for 4 months. Survival in this group was 16 months versus 5 months for patients with a mixed response and progression of disease. Of 11 patients with evaluable parameters only 1 had stabilization and 5 showed subjective improvement. Recognizing the patient selection bias and treatment schedule in this study, we believe that doxorubicin has marginal activity in soft tissue lesions in patients with advanced prostatic cancer.

Adriamycin and cyclophosphamide versus hydroxyurea in advanced prostatic cancer. A randomized Southwest Oncology Group study

Over a 24-month period, the Southwest Oncology Group (SWOG) conducted a randomized prospective chemotherapeutic trial in 158 patients with advanced prostatic cancer. Patients were initially randomized to receive either a combination of Adriamycin and cyclophosphamide (AC) or a single agent, hydroxyurea (H), and then crossed over to the other treatment on failure. Of the 137 evaluable patients, 43 (31%) had classically measurable metastatic disease in the lymph nodes, skin, chest, or liver. Focusing their efforts on this subset of patients with measurable disease, the authors of this report found the combination AC to have a superior response rate to the single agent, hydroxyurea. Objective response to AC was seen in 6 of 19 (32%) and in only one of 24 (4%) patients randomized to hydroxyurea (P = 0.06, Fisher's exact test). However, in the larger group of 137 evaluable patients, a survival advantage was not seen for those individuals treated with AC. Failure to demonstrate a survival advantage for an objectively superior drug combination would suggest the need for more active phase II agents in this disease.

Chemotherapy principles in the treatment of prostatic cancer

The efficacy of chemotherapy for prostatic cancer is difficult to evaluate owing to the low incidence of measurable indicator lesions and the resulting need for indirect response criteria. Although complete regressions remain exceptional, a number of agents, eg, doxorubicin and cisplatin have been shown to be effective in the treatment of this disease. So far, combinations of effective agents with or without concomitant hormone therapy have not proven to be more effective than single agents. Androgen priming has considerable theoretical appeal and deserves further consideration. A higher effectiveness of chemotherapeutic agents might be obtained by linkage to various carriers. Estramustine phosphate is an example of such a complex that has a cytotoxic effect in test systems in which estrogen has no effect and in patients with hormone-refractory prostatic cancer. The use of hormonal and other carriers that could increase the specificity of chemotherapeutic agents deserves extensive exploration.

A phase II evaluation of adriamycin and cis-platinum in hormone resistant prostate cancer

Twenty-five patients with metastatic prostate cancer were treated with a combination of Adriamycin 50 mg/m2 and cis-platinum (CDDP) 50 mg/m2 every three weeks. Response was evaluated using radioisotope bone scan, serum acid phosphatase levels, and clinical status. Response rates of 6% bone, 21% acid phosphatase, and 24% clinical status were noted. Major toxicity was gastrointestinal (due to CDDP). Treatment was well tolerated even in patients with extensive bone metastases and prior irradiation. Using the response criteria described here, patients with metastatic prostate cancer without measurable soft tissue disease are eligible for Phase II and III study.

Response of lymph node metastasis to sequential estrogen and radiation therapy in prostate carcinoma

Increasingly sophisticated diagnostic studies have shown a high incidence of tumor spread to the regional lymph nodes. The status of the lymph nodes has been evaluated by noninvasive diagnostic procedures such as lymphangiography and computerized axial tomography. The applicability of these procedures has been enhanced by the use of stringent criteria. Gross lymph node metastasis can be diagnosed with considerable confidence. Serial observations of lymphangiograms and computerized axial tomograms before and two months after the administration of estrogens provide an added dimension to the interpretation of lymph node metastasis. The nature and range of the response of lymph node metastasis were observed. Survival of patients with gross lymph node metastasis treated by sequential estrogen and radiation therapy was evaluated. A total of 11/18 (61 per cent) of patients remained free of symptoms, 8/11 (74 per cent) with a favorable lymph node metastasis responsive to estrogen therapy, and 3/7 (42 per cent) with lymph node metastasis refractory to estrogen therapy. Follow-up computerized axial tomograms of the lymph nodes done at one and two years after irradiation showed a persistent favorable response. Five patients are alive with disease, and 2 patients died of the disease.

Histological evaluation of radiochemotherapy for prostatic cancer: early results of a pilot study

Antiandrogen therapy has been widely used for prostatic cancer, yet many authors have reported on the limited efficacy of hormonal therapy for this disease. The present report is based on an histological evaluation of chemotherapy and radiotherapy in combination for prostatic cancer. To determine the usefulness of this combined therapy, 15 prostatic cancer patients were treated with a combination of Bleomycin and Adriamycin (BA therapy), or with only Adriamycin. Radiotherapy was administered to all cases. Twelve of the 15 patients were evaluable histologically with effects ranging from Grade I to Grade IV in Shimosato's classification. We conclude that further investigation, including a randomized study of hormonal therapy, is necessary.