Proceedings: Hormone-induced and spontaneous regression of metastatic renal cancer

Genetic and Epigenetic Characteristics in Isolated Pancreatic Metastases of Clear-Cell Renal Cell Carcinoma

Isolated pancreatic metastases of renal cell carcinoma (IsPMRCC) are a rare manifestation of metastatic, clear-cell renal cell carcinoma (RCC) in which distant metastases occur exclusively in the pancreas. In addition to the main symptom of the isolated occurrence of pancreatic metastases, the entity surprises with additional clinical peculiarities: (a) the unusually long interval of about 9 years between the primary RCC and the onset of pancreatic metastases; (b) multiple pancreatic metastases occurring in 36% of cases; (c) favourable treatment outcomes with a 75% 5-year survival rate; and (d) volume and growth-rate dependent risk factors generally accepted to be relevant for overall survival in metastatic surgery are insignificant in isPMRCC. The genetic and epigenetic causes of exclusive pancreatic involvement have not yet been investigated and are currently unknown. Conversely, according to the few available data in the literature, the following genetic and epigenetic peculiarities can already be identified as the cause of the protracted course: 1. high genetic stability of the tumour cell clones in both the primary tumour and the pancreatic metastases; 2. a low frequency of copy number variants associated with aggressiveness, such as 9p, 14q and 4q loss; 3. in the chromatin-modifying genes, a decreased rate of PAB1 (3%) and an increased rate of PBRM1 (77%) defects are seen, a profile associated with a favourable course; 4. an increased incidence of KDM5C mutations, which, in common with increased PBRM1 alterations, is also associated with a favourable outcome; and 5. angiogenetic biomarkers are increased in tumour tissue, while inflammatory biomarkers are decreased, which explains the good response to TKI therapy and lack of sensitivity to IT.

Patients with metastatic renal cell carcinoma who receive immune-targeted therapy may derive survival benefit from nephrectomy

BACKGROUND

Nephrectomy, whether in the era of cytokine therapy or targeted therapy, has an important role in the treatment of metastatic renal cell carcinoma. With the advent of immunotherapy, immunotherapy combined with targeted therapy has become the mainstream of systemic therapy, but the role of nephrectomy in metastatic renal cell carcinoma is unclear. In this study, we retrospectively analyzed the impact of nephrectomy on survival in patients with metastatic renal cell carcinoma who received immune-targeted therapy.

METHODS

Patients with metastatic renal cell carcinoma who received immune-targeted therapy at three centers between May 17, 2019 and August 1, 2022 were collected, who were divided into two groups based on whether nephrectomy was performed or not. Survival, response rate and adverse event were compared between the two groups. The primary end point was progression free survival, Subgroup analysis and univariate and multivariable prognostic analyses were also assessed.

RESULTS

With a median follow-up time of 29.3 months (95% CI 28.5-30.2), 165 patients were recruited and divided into two groups based on whether they underwent nephrectomy or not. There were 68 patients in the non-nephrectomy group, 97 in the nephrectomy group. Compared to patients treated with immune-targeted therapy, patients treated with immune-targeted therapy plus nephrectomy were able to achieve survival benefits, with a median PFS of 10.8 months (95% CI 8.3-13.3) and 14.4 months (95% CI 12.6-16.2), respectively, as well as an HR of 0.476 (95% CI 0.323-0.701, p = 0.0002). The 12-month and 18-month PFS rates were 30.9% versus 60.8% and 7.4% versus 25.8%, respectively. The objective response rate (ORR) was 52.9% and 60.8%, respectively, in the non-nephrectomy and nephrectomy groups (p = 0.313), and the disease control rate (DCR) was 75% and 83.5%, respectively (p = 0.179). The most common adverse events related to treatment were hypothyroidism, immune-related pneumonitis and rash. Multivariate analysis showed that primary tumor nephrectomy prior to immune-targeted therapy, clear cell renal carcinoma and oligo metastasis were independent prognostic factors.

CONCLUSIONS

Nephrectomy may provide PFS benefit with tolerable safety for patients with metastatic renal cell carcinoma who receive immune-targeted therapy. In multivariate analysis, nephrectomy, clear cell carcinoma, and oligo-organ metastasis were found to be favorable independent prognostic factors.

Isolated Pancreatic Metastases of Renal Cell Carcinoma-Clinical Particularities and Seed and Soil Hypothesis

A meta-analysis of 1470 isolated pancreatic metastases of renal cell carcinoma revealed, that, in addition to the unusual exclusive occurrence of pancreatic metastases and the favourable treatment results, the isPMRCC is characterised by further peculiarities of the clinical course: The lack of prognostic significance of volume and growth rate dependent risk factors and the independence of treatment results from standard or local resections. As an explanation for all these peculiarities, according to today's knowledge, a strong acting seed and soil mechanism can serve, which allows embolized tumour cells to grow to metastases only in the pancreas, and prevents them definitively or for years in all other organs. The good prognosis affects not only isolated PM, but also multi-organ metastases of the RCC, in which the additional occurrence of PM is also associated with a better prognosis. Genetic studies revealed specific changes in cases of PM of RCC: Lack of loss of 9p21.3 and 14q31.2, which are otherwise specific gene mutations at the onset of generalization, a low weight genome instability index, i.e., high genetic stability, and a low rate of PAB1 and a high rate of BPRM1 alterations, which signal a more favourable course. The cause of pancreatic organotropism in isPMRCC is still unclear, so only those factors that have been identified as promoting organotropism in other, more frequent tumour entities can be presented: Formation of the pre-metastatic niche, chemokine receptor-ligand mechanism, ability to metabolic adaptation, and immune surveillance.

Isolated Pancreatic Metastases of Renal Cell Cancer: Genetics and Epigenetics of an Unusual Tumour Entity

Isolated pancreatic metastases of renal cell carcinoma (isPMRCC) are a rare manifestation of metastatic renal cell carcinoma (mRCC) characterized by two peculiarities: (1). The definite or at least long-term exclusive occurrence of metastases in the pancreas and (2). an unusual low tumour aggressiveness with slow tumour progression and consecutive, good treatment results. According to current knowledge, the exclusive occurrence of pancreatic metastases is due to a highly specific and highly selective seed and soil mechanism, which does not allow metastases settlement outside the pancreas, and whose detailed genetic/epigenetic causes are not yet elucidated. Recent studies have shed light on some of the pathways involved for the protracted course of the disease and highlighted a special genetic profile (lack of loss of 9p, lower weight genome instability index, low frequency of BAP1 alterations, and a high frequency of PBRM1 loss), which deviates from the conventional mRCC profile. Finally, the question of the reasons for the long-term relative genetic stability of the involved cell clones, which is an essential prerequisite for a favourable prognosis, remains unanswered.

Recombinant interferon alpha-2 in advanced renal cell carcinoma

From January 1985 to December 1987, 26 patients (20 men, 6 women, median age 62 years, range 26–76 years) with advanced renal cell carcinoma were included in the study. In 8 cases (6 patients no surgery, 2 patients with retroperitoneal node-residual disease after nephrectomy) metastases were identified at initial diagnosis, and in the remaining 18 the occurrence of metastases was delayed by a mean disease-free interval of 12 months after radical nephrectomy. Recombinant interferon alpha-2 was administered subcutaneously at a dose of 9 milion IU three times a week for a period of at least six months. Informed consent was obtained from all patients before starting therapy. No patients achieved complete regression of tumors; two cases showed a partial response (one relapsed six months later, while in the other response continues at 38 months after discontinuation of therapy); 10 patients showed stabilization of disease for 6–10 months and in 14 the disease progressed immediately. In our experience immunotherapy with recombinant interferon alpha-2 did not significantly change the natural history of renal cell carcinoma.

Estrogen Receptors and MPA Treatment in Metastatic Renal Carcinoma. A Preliminary Report

Ten previously untreated patients with metastatic renal carcinoma underwent transperitoneal radical nephrectomy followed by high dosage MPA treatment. Estrogen receptors were determined in the specimen of all cases by the dextran-coated charcoal method: both the neoplastic tissue and the healthy parenchyma were tested. The disease progressed in 8 cases, and 2 patients are alive without any evidence of progressive disease 12 and 27 months after the operation. Very low receptor levels were detected in these 2 cases and one of them could be defined as borderline with our threshold criterion. However, receptors were undetectable in the neoplastic tissue from 4 of 8 patients who progressed. These questionable results justified the start of a prospective multicentric trial to study in a large number of cases both hormone receptors and clinical response to hormone therapy in human renal cancer.

Medical Treatment of Metastatic Renal Cell Carcinoma

Thirty five patients with metastatic RCC were observed over a 57 months period in our Division of Radiotherapy and Medical Oncology, and 30 are evaluable for this analysis. MPA was selected as primary treatment agent in 23 patients, VLB singly, in combination with MPA or in combination with CCNU was used in 1.4 and 2 patients. With MPA the TR rate was 3/23 (1 CR and 2 PR). Duration of response for the patient with CR was 6 months whereas for the patients with PR was 21 and 14 months respectively. 4 additional patients showed NC. With VLB-MPA the TR rate was 1/4 (1 PR). Duration of PR was 3 months. The median duration of survival for the 11 patients with CR, PR and NC was 14 months whereas for the 19 patients with NR was 7 months (p < 0.01). TES and TAM showed no or minimal activity as second treatment agents.

Renal cell carcinoma (RCC) and telomerase activity: relationship to stage

Limited information is available on the correlation of telomerase activity and the clinical and pathological characteristics, in patients with renal cell carcinoma (RCC). Telomerase repeat amplification protocol (TRAP) was used to measure telomerase activity in frozen RCC specimens from partial/radical nephrectomies performed between 1987 and 1991. Presence of tumor tissue was verified by a pathologist using hematoxylin and eosin stained sections. RNA was measured to ensure the presence of intact protein necessary for telomerase expression. Data on demographics, tumor type, and stage at presentation, local recurrence, distant metastasis, disease-free survival (DFS), and overall survival (OS) was collected, and telomerase activity was correlated with each of these variables. Forty-nine of 67 patients (73%) were telomerase positive (+ve). Gender and stage were the only variables that appeared to be associated with telomerase positivity. Tumors were telomerase +ve in 12/21 females (57 %) vs. 37/46 males (80%) (P = 0.07). Tumors were telomerase +ve in 85% of Stage IV, 76% of Stage III, and 70% of Stage I/II patients (P = 0.12). Five-year survival was 0% for Stage IV, 57% for Stage III, and 77% for Stage I/II patients (P < 0.001), DFS 54% for stage III and 84% for Stage I/II patients (P = 0.05). Telomerase activity, however, was not related to survival in either univariate or multivariate analysis. In patients with telomerase +ve tumors 5-year survival was 55%, and with telomerase -ve tumors 58% (P = 0.56). Stage was the only variable associated with OS or DFS in clear cell RCC patients. In patients with advanced disease, there is a high incidence of telomerase positivity was found, within this limited sample, however, no correlation with survival was found.

Antineoplastic Effects of Partially HLA-Matched Irradiated Blood Mononuclear Cells in Patients With Renal Cell Carcinoma

Purpose: Vaccines, cytokines, and other biologic-based therapies are being developed as antineoplastic agents. Many of these agents are designed to induce an autologous immune response directed against the malignancy. In contrast, hematopoietic stem-cell transplantation is being developed as a form of allogeneic immunotherapy. This study tests the tolerance and antineoplastic activity of sequential infusions of partially HLA-matched allogeneic blood mononuclear cells (obtained from relatives) when administered outside of the context of a hematopoietic stem-cell transplantation. The cells are irradiated to prevent graft-versus-host disease.

Patients and Methods: Fifteen patients with relapsed or refractory malignancies for which no standard therapy was available were enrolled onto a clinical trial designed to assess the tolerability and antineoplastic effects of irradiated partially HLA-matched blood mononuclear cells obtained from relatives.

Results: There was disease regression in three patients with metastatic renal cell carcinoma during treatment. There was disease progression in six patients with metastatic renal cell carcinoma and two patients with metastatic melanoma during treatment. There was no change in disease state in several other patients.

Conclusion: Irradiated allogeneic blood mononuclear cells administered outside the context of hematopoietic stem-cell transplantation may induce disease responses in patients with relapsed or refractory malignancies. Transfusion of irradiated allogeneic blood mononuclear cells should be developed further as a novel therapeutic antineoplastic approach.

Synchronous renal cell carcinoma and gynecologic malignancies

BACKGROUND

Synchronicity of renal cell carcinoma and gynecologic malignancies is a rare condition and standardized treatment does not exist.

CASES

Three cases of synchronous renal cell carcinoma and gynecologic malignancies are described. All three cases underwent optimal cytoreductive surgery for the gynecologic malignancy and a radical nephrectomy for the renal cell carcinoma. Adjuvant treatment, after surgery, was individualized in each case. Estrogen and progesterone receptors were positive in all the gynecologic tumors but negative in the renal cell tumors.

CONCLUSIONS

This is apparently the largest report of synchronous renal cell carcinoma and gynecologic malignancies. Despite this rare condition, surgery should still be considered as primary treatment for these patients.

The biological treatment of renal-cell carcinoma and melanoma

Biological therapies are claiming a place in the routine management of some solid tumours. In this review we focus on the biological treatment of melanoma and renal-cell carcinoma, identifying the background to current practice and areas of promise that may be in routine clinical use in the near future. Melanomas and renal-cell carcinomas are particularly resistant to chemotherapy and radiotherapy and are characterised by the host immune response to the tumours. For this reason there has been particular interest in the biological therapy of these diseases. Biological therapies differ from chemotherapeutic approaches in their mechanism of action, time to response, and side-effect profiles. Although biological treatment has a long history, it is only with recent advances in immunology and molecular biology that progress has been made. In the next few years investigators expect to build on their research experience with biotherapeutic agents to provide tangible benefits for patients.

Placebo-associated remissions in a multicentre, randomized, double-blind trial of interferon gamma-1b for the treatment of metastatic renal cell carcinoma. The Canadian Urologic Oncology Group

OBJECTIVE

To determine the validity of using an historical maximum spontaneous regression rate (reportedly 0-1.1% in those with lung metastases after nephrectomy) in clinical trials of treatments for patients with metastatic renal cell carcinoma (RCC), as the eligibility criteria for most studies will select patients with better performance status (and thus excluding those who are unlikely to respond) and more modern staging methods would potentially reduce the number of false-positives.

PATIENTS AND METHODS

A multicentre randomized,placebo-controlled, double-blind trial was recently completed in which 197 patients with metastatic RCC from 17 study centres across Canada were randomized to receive placebo or recombinant interferon gamma-1b (60 microg/m2) subcutaneously once every 7 days until disease progression. All tumour responses were validated by an independent response committee unaware of the treatment.

RESULTS

The median (95% confidence interval) overall response rate (complete, CR, and partial, PR) for those on interferon-gamma was 4 (1.4-11.5)% and for those on placebo was 6 (2. 5-13.2)% (P = 0.75). In the six patients who were receiving placebo the CR and PR (three each) was considered to represent spontaneous remission. Of these six patients (aged 44-64 years) five had undergone nephrectomy, one a tumour embolization, four had clear cell carcinoma and one an adenocarcinoma, and all had regression of lung and/or lymph node metastases.

CONCLUSION

The lack of efficacy of interferon-gamma in this trial underlines the importance of continued research to identify alternative therapeutic agents or combinations of agents in phase II studies. However, the threshold response rate for initiating phase III trials should be increased to 18% in the phase II trials, i.e. three times the response rate on placebo.

Serum immunosuppressive acidic protein and natural killer cell activity in patients with metastatic renal cell carcinoma before and after nephrectomy

PURPOSE

To our knowledge the impact of nephrectomy on stage M1 renal cell carcinoma remains to be determined. We previously reported that nephrectomy is beneficial in patients with elevated serum C-reactive protein before treatment, and those in whom nadir C-reactive protein decreases postoperatively to within the normal range may expect longer survival when surgery is combined with postoperative immunotherapy. In this study we determine the effect of nephrectomy on the immune response in patients with metastatic renal cell carcinoma.

MATERIALS AND METHODS

We retrospectively reviewed the records of 40 patients with metastatic renal cell carcinoma diagnosed at our institution between 1986 and 1999. These patients underwent nephrectomy before cytokine therapy with interferon. Before and after nephrectomy we measured serum C-reactive protein, serum immunosuppressive acidic protein and peripheral blood natural killer cell activity.

RESULTS

In 15 patients with pretreatment serum C-reactive protein within the normal range (less than 1 ng./ml.) there was no significant difference before and after nephrectomy in the serum immunosuppressive acidic protein level or natural killer cell activity (p = 0.4587 and 0.3892, respectively). On the other hand, in 25 patients with serum C-reactive protein elevated before treatment to 1 ng./ml. or greater serum immunosuppressive acidic protein decreased significantly and natural killer cell activity increased significantly after cytoreductive surgery (p = 0.0002 and 0.0286, respectively).

CONCLUSIONS

Our study implies that nephrectomy may be beneficial in patients with elevated serum C-reactive protein before treatment. Further evaluation by a prospective study is needed to make a definitive conclusion.

Serum C-reactive protein level and the impact of cytoreductive surgery in patients with metastatic renal cell carcinoma

PURPOSE

The prognosis of metastatic renal cell carcinoma is extremely poor. In this type of metastatic tumor cytoreductive surgery of the primary tumor is often performed to confirm the histological type or improve the response to immunotherapy with agents such as interferon or interleukin-2. However, the timing and impact of cytoreductive surgery on the success of immunotherapy require further study. We determined the type of metastatic renal cell carcinoma for which cytoreductive surgery is beneficial.

MATERIALS AND METHODS

We retrospectively reviewed the records of 58 patients in whom metastatic renal cell carcinoma was diagnosed at our hospital between 1986 and 1997. Three patients were excluded from study because they were judged to be poor candidates for surgery due to poor performance status. Of the remaining 55 patients 34 consented to cytoreductive surgery of the primary tumor and 21 did not. All except 1 patient were treated with interferon therapy. We evaluated the association of pretreatment serum C-reactive protein and the effect of surgery.

RESULTS

We noted no significant difference in age at diagnosis, pretreatment serum immunosuppressive acidic protein, site of metastasis or performance status in 34 patients who underwent cytoreductive surgery and 21 who did not. Of the 21 patients in whom pretreatment serum C-reactive protein was within normal limits (less than 1.0 ng./ml.) no significant difference in disease specific survival was observed in those who did and did not undergo surgery (p = 0.4133). On the other hand, of 34 patients in whom pretreatment serum C-reactive protein was elevated (1.0 ng./ml. or greater) the prognosis was significantly better in those who did versus those who did not undergo surgery (p = 0.0054). Particularly the prognosis in patients in whom postoperative nadir C-reactive protein decreased to within normal limits was markedly better than in those in whom it remained elevated (p = 0.0025).

CONCLUSIONS

Our study suggests that cytoreductive surgery is beneficial to patients in whom pretreatment serum C-reactive protein is elevated. Particularly, those in whom serum C-reactive protein decreases to within normal limits may expect longer survival when surgery is combined with postoperative immunotherapy. Currently to our knowledge the prognostic factor that predicts postoperative nadir C-reactive protein has not been identified, indicating that cytoreductive surgery of the primary tumor should be performed in patients with elevated pretreatment C-reactive protein and as performance status permits.

Renal cell carcinoma: a paradigm of lanthanic disease

Renal cell carcinoma is characterized by varied and sometimes obscure manifestations, which include unusual metastatic sites and paraneoplastic and vascular syndromes. In this review, uncommon metastatic sites and their clinical significance are discussed, particularly the thyroid, nasal structures, vagina, and gastrointestinal sites. Paraneoplastic syndromes appear to be related predominantly to cytokines or immunologic mechanisms. Vascular syndromes are related to the tendency of the tumor to spread by direct venous extension and to complications related to the vascularity of the tumor or its metastases. The recognition of unusual manifestations of renal cell carcinoma is important because these syndromes may lead to the diagnosis. Moreover, paraneoplastic syndromes and vascular findings may not indicate unresectability or incurability.

British urological surgery practice: 2. Renal, bladder and testis cancer

OBJECTIVE

To investigate the management of urological malignancies in the United Kingdom.

METHODS

A postal survey of consultant urologists and general surgeons with an interest in urology was conducted to examine current clinical practice in urological malignancies.

RESULTS

Completed questionnaires were received from 273 consultant surgeons who saw an estimated total of 13241 new patients with renal, bladder or testis cancer per year; 82% had access to on-site oncology services and in general there was a consensus in the answers given. Most respondents advised active treatment of an asymptomatic primary renal cancer in the presence of metastases and a significant proportion of patients with metastases were not prescribed immunotherapy nor were offered a multidisciplinary approach for their condition. Forty-six per cent of patients with testis cancer received no advice to store sperm before chemotherapy and there were varied opinions as to the need for surgical resection of residual masses after completion of chemotherapy.

CONCLUSION

This survey showed minor variations in the management of renal, bladder and testis tumours in the UK. Consensus management guidelines for urological malignancies and a change in the working relationships between urologists and oncologists is required, to improve the outcome of patients with urological malignancy.

Renal cell carcinoma

Renal cell carcinoma (RCC) is characterized by (a) lack of early warning signs, which results in a high proportion of patients with metastases at the time of diagnosis; (b) protean clinical manifestations; and (c) resistance to radiotherapy and chemotherapy. The estimates of new diagnoses and deaths from kidney cancer in the United States during 1996 are 30,600 and 12,000, respectively. RCC occurs nearly twice as often in men as in women. The age at diagnosis is generally older than 40 years; the median age is in the midsixties. The incidence of RCC has been rising steadily. Between 1974 and 1990, there was a 38% increase in the number of patients who had a diagnosis of RCC. This increase was accompanied by a significant improvement in 5-year survival. Both trends are likely the result of improved diagnostic capability. Newer radiographic techniques, including ultrasonography, computed tomography, and magnetic resonance imaging, are detecting kidney tumors more frequently and at a lower disease stage, when tumors can be resected for cure. Surgical treatment is the only curative therapy for localized RCC. Radical nephrectomy remains the mainstay of surgical management, but techniques are being modified. These modifications include partial nephrectomy and resection of vena caval thrombi. In highly selected cases, surgical resection of locally recurrent RCC or of disease at a solitary metastatic site is associated with long-term survival. Metastatic RCC is highly resistant to the many systemic therapies that have been extensively investigated. A minority of patients achieve complete or partial response to interferon, interleukin-2, or both. Response can be dramatic but is rarely durable. Because most patients do not achieve response, these agents are not considered effective treatments for RCC, but the response in some patients indicates the need for continued research on their use. Identification of new agents with better antitumor activity against metastases remains a high priority in clinical investigation of therapy for this refractory disease.

Metastatic renal cell carcinoma in a child: 11-year disease-free survival following surgery

A child with metastatic renal cell carcinoma (RCC) is presented. This case is unusual in that the patient has remained disease free for 11 years following surgery and only one course of chemotherapy prior to thoracotomy. The management of metastatic RCC is reviewed and the genetic mechanisms leading to its development briefly discussed.

Spontaneous caval tumor thrombus necrosis and regression of pulmonary lesions in renal cell cancer

Idiopathic regression of metastases is one of the features of the unpredictable behaviour of renal cell carcinoma. We report a patient with pulmonary metastases and a tumor thrombus in the inferior vena cava with spontaneous regression of the lung lesions and necrosis of the thrombus before any therapy was instituted.

Natural killer cells and cancer

BACKGROUND

Natural cytotoxicity, mediated by natural killer (NK) cells and cell with lymphokine-activated killer (LAK) activity, is believed to play an important role in host anti-cancer mechanisms.

METHODS

The authors critically review recent publications on the role of natural cytotoxicity in patients with cancer.

RESULTS

In patients with cancer, several studies have noted variations in the numbers and activity of NK and cells with LAK activity in different body compartments. NK cell activity in the peripheral blood lymphocytes (PBLs) is higher than that found in lymph nodes and within tumors, and this appears to be due to the presence of suppressor factors. The natural cytotoxicity of PBLs in patients with different types of cancers varies. However, there appears to be a trend for natural cytotoxicity to be reduced in certain cancer patients, possibly related to tumor volume or dissemination. Anti-cancer treatments (e.g., surgery, hormonal modulation, radiotherapy and chemotherapy) can also result in suppression of natural cytotoxicity, although the long-term effect on response to treatment and development of metastases is at present unknown.

CONCLUSIONS

NK and LAK cells, through the use of immune biologic modifiers, have been demonstrated to have a therapeutic role in the treatment of human cancers. Further studies are required to determine the optimal dosages and combinations of chemotherapeutic agents, the timing of surgery, and the adjuvant use of immune biologic response modifiers. An increasing awareness and understanding of this field, may allow for the future development of anti-cancer therapies.

Medical treatment of advanced renal cell carcinoma: present options and future directions

The treatment of patients with metastatic renal cell carcinoma (MRCC) continues to be disappointing. A large number of hormones, chemotherapeutic agents and combinations have been tested with poor and non-reproducible results. Among the immunological treatments investigated in MRCC, the best results have been claimed with interferons (IFNs) and interleukin-2 (IL-2) and, although no randomized studies have shown higher activity than cytotoxic drugs, hormones or even no treatment, many oncologists feel it justified to consider these biologic agents the treatment of choice for this disease. Of patients treated with alpha-IFN, 15-20% achieve an objective remission and 3-5% achieve a long-lasting complete response. No substantial increase of the therapeutic activity of alpha-IFN was produced by combination with chemotherapeutic agents and gamma-IFN or tumour necrosis factor. High doses of IL-2 with or without lymphokine-activated killer cells led to successful results in about 20-30% of patients with 5-10% complete responses. More recently, less toxic regimens with lower doses of IL-2 alone or combined with alpha-IFN produce similar response rates. Many studies have clarified the importance of prognostic factors in patient selection for response and survival during treatments with IFNs and IL-2. Good performance status, a long interval from diagnosis to treatment, and only one site of disease seem to be the most important predictors for survival. Both IFNs and IL-2 appear to possess encouraging antitumour activity in patients with favourable prognostic factors, but further studies are needed to identify the treatment of choice, the optimal dose regimen and route of administration in this subgroup of patients. Patients with poor prognosis should be encouraged to enter controlled studies aimed to evaluate investigational drugs and new therapeutic methods.

Spontaneous regression of metastatic renal cell carcinoma following palliative irradiation of the primary tumour

A 58 years old man presented with a bulky renal primary tumour, paratracheal lymphadenopathy and multiple pulmonary metastases. Spontaneous regression of intrathoracic metastases occurred after low dose palliative irradiation of the primary tumour. Serum levels of Interleukin-2 receptor were elevated during the period of tumour regression but concentrations of other cytokines were normal. Progressive abdominal disease eventually caused death. Autopsy confirmed the presence of renal cell carcinoma with intrathoracic metastases.

Spontaneous remission of renal cell carcinoma: a case report and immunological correlates

Spontaneous remission of renal cell carcinoma is a rare occurrence for which immunological factors have been implicated as a possible mechanism. We report a case of spontaneous remission of metastatic renal cell carcinoma in which we assayed various immune parameters. At remission we found no enhancement of natural killer cell, lymphokine-activated killer cell or lymphocyte proliferative response.

Regression of metastatic renal cell carcinoma after cytoreductive nephrectomy

Fewer than 1% of patients with renal cell carcinoma are reported to experience spontaneous regression of metastatic lesions after nephrectomy. We report on 4 of 91 patients (4.4%) with metastatic renal cell carcinoma who had spontaneous regression of all metastatic lesions after cytoreductive nephrectomy. These patients were carefully selected before surgery for the ability to receive high dose interleukin-2. One patient had recurrence at 2 months, 1 had recurrence at 11 months, and 2 had no evidence of disease at 3 and 4.5 years.

Hormonal regulation of rat renal cytochrome P450s by androgen and the pituitary

The hormonal regulation of rat renal cytochrome P450s, P450 4A2 (K-5) and K-2, was investigated. The level of P450 4A2 in male rats was five times that in female rats and accounted for some 90% of total cytochrome P450, measured photometrically. Lauric acid omega- and (omega-1)-hydroxylation activities of renal microsomes of male rats were also higher than those of female rats. The sex differences in lauric acid hydroxylation activity seemed to arise from the differences in P450 4A2 concentrations, according to an immunochemical study. P450 K-2 was a female-dominant form in rat kidneys. The level of P450 K-2 in renal microsomes of male rats was one-tenth that of P450 4A2. Castration of male rats decreased the levels of P450 4A2 and treatment of castrated male rats with testosterone reversed the decrease. The castration of male rats decreased the lauric acid hydroxylation of the renal microsomes to the level of female rats. The administration of testosterone to castrated male rats reversed the decrease. Hypophysectomy of male rats decreased the level of P450 4A2 and the administration of growth hormone reversed the decrease when intermittent injections mimicking the male secretory pattern were given, although continuous administration mimicking the female secretory pattern did not. Castration of male rats did not affect the level of P450 K-2, but testosterone decreased its level. Hypophysectomy of male rats increased the level of P450 K-2 and growth hormone decreased its level in hypophysectomized rats. These results suggested that the expression of P450 4A2 was regulated by androgen or growth hormone and regulation of P450 4A2 was different from that of P450 K-2. To explore the regulation of renal cytochrome P450 further, testosterone was given to control (intact) or hypophysectomized adult female rats. P450 4A2 was induced in the kidneys of both control and hypophysectomized female rats to close to the level of male rats. Thus, P450 4A2 was directly regulated by testosterone as well as growth hormone, and the regulation of the male-dominant form in rat kidneys was different from that of the male-specific form in the rat liver, which is regulated mostly by growth hormone.

Spontaneous regression of histologically proved pulmonary metastases from renal cell carcinoma: a case with 5-year followup

Spontaneous regression of biopsy proved metastatic renal cell carcinoma is rare. We describe a 39-year-old man who had histologically proved metastatic disease to the lungs after nephrectomy. The lesions had spontaneously regressed 3 months later. The patient remained without evidence of recurrence 5 years after diagnosis.

Spontaneous regression of metastases in a case of bilateral renal cell carcinoma

A patient is described who had undergone bilateral nephrectomy for renal cell carcinoma and who had been maintained on hemodialysis for the last 2 years. A total of 3 months after acceptance into the program he was found histologically to have metastatic pleural lesions, which had regressed spontaneously 1 1/2 years ago. Repeat clinical and radiological assessment has shown no tumor recurrence.

Metastatic renal cell cancer treated with recombinant alpha 2a interferon and vinblastine

42 patients with advanced renal cell carcinoma were treated with a combination therapy with interferon alpha 2a (mean dosage 16 x 10(6) U i.m. 3 times/week) and vinblastine (0.1 mg/Kg every 21 days). 12 patients (28.5%) had a positive response. Of them 1 presented a complete response (2.38%), 5 a partial response (11.9%) and 6 a stable disease (14.2%). No significant side effects were observed apart from the flu-like syndrome (all patients) and a moderate leukopenia (45.2%). The median duration of responses was 10+ months (range 3-37 months). At 4-year follow-up the median survival time was 16.0 months (range 4-37 months).

Metastatic renal cell carcinoma (RCC): spontaneous regression, long-term survival and late recurrence

We report 4 cases of metastatic renal cell carcinoma (RCC) with long-term survival either following radical nephrectomy alone or in combination with radio- or hormonal therapy. Two patients with lymph node metastases showed a long-term survival of 12 or more years following radical tumour nephrectomy (with lymphadenectomy) and radiotherapy. One of them exhibited a histologically proven tumour recurrence nearly 12 years after primary surgical treatment and died shortly later; the other one is still without any evidence of metastatic disease. Two other patients exhibited spontaneous regression of pulmonary metastases: one regression occurred after radical tumour nephrectomy alone, the other one after successful primary hormonal treatment and subsequent radical tumour nephrectomy. The following important aspects are emphasized: 1. Renal cell carcinoma is a very unpredictable tumour. Once the diagnosis of renal cell carcinoma is proved, a patient can never be considered cured. 2. Although adjuvant palliative nephrectomy has produced contradictory results in several reports, radical tumour nephrectomy either alone or in combination with other adjuvant therapies such as radiotherapy, hormonal or immunological treatment, can be worthwhile. Cases with long-term survival and spontaneous regression of distant metastases are proof of this. Besides, if carefully selected, the mortality rate of different adjuvant therapies is not significantly higher in patients with metastatic disease than in patients without metastases. The world literature on this subject is reviewed.

Testosterone-mediated regulation of mouse renal cytochrome P-450 isoenzymes

We have studied the extent to which mouse renal cytochrome P-450 isoenzymes are sexually differentiated, and the factor(s) regulating this dimorphism. Intriguingly, sex differences were not seen in the expression of a single cytochrome P-450 enzyme, but were observed in the expression of all P-450 isoenzymes detectable, encoded by six gene families or sub-families. This effect was mediated by testosterone, which had the capacity to both induce and repress P-450 gene expression, and which was independent of growth hormone. The changes in protein content were mirrored in all but one case by changes in the levels of mRNA, indicating that these genes contain hormone-responsive elements. These findings are consistent with numerous reports of sex differences in the susceptibility of the mouse kidney to the toxic and carcinogenic effects of drugs and environmental chemicals, many of which are metabolized to cytotoxic products by the cytochrome P-450-dependent mono-oxygenases. These data imply that circulating androgen levels will be an important factor in susceptibility of the kidney to toxic or carcinogenic compounds which require metabolic activation.

Estrogen and progesterone binding sites in renal cell carcinoma

Twenty-five renal cell carcinomas were assayed for estrogen and progesterone receptor levels. Estrogen specific binding was present in only 4 patients (16%) and progesterone specific binding in 7 patients (28%). In all cases these receptors were present in very low titers, less than 10 fm/mg. We believe that earlier reports citing significant estrogen and progesterone binding activity may reflect high levels of nonspecific protein binding.

Tissue specific regulation of renal N-nitrosodimethylamine-demethylase activity by testosterone in BALB/c mice

Nitrosodimethylamine (NDMA), like several other nitrosamines, is activated by the enzymes--mixed-function oxidases--present in the tissue microsomal fractions, producing mutagenic and carcinogenic effects. Previous studies in BALB/c mice have shown an age, sex and androgenic regulation of NDMA-induced mutagenicity. The present study was designed to test the correlation between renal NDMA-demethylase activity and previously published reports on NDMA-induced mutagenicity. Renal and hepatic NDMA-demethylases were determined from the microsomal fractions by quantitating formaldehyde. Renal NDMA-demethylase showed the presence of two isozymes, I and II, with Km values of 0.6 +/- 0.2 and 20.2 +/- 6.8 mM respectively. Isozyme I was detected in adult males and first appeared at the onset of puberty; it was absent in adult females and in immature mice. Renal isozyme II was detected in both males and females and was independent of age. Testosterone treatment of adult females resulted in the appearance of renal isozyme I. Castration of adult males caused a dramatic decrease in activity, whereas testosterone administration to such castrates increased activity, of renal isozyme I. Hepatic NDMA-demethylase activities were independent of age, sex or testosterone treatment. In conclusion, these results show an age, sex and tissue specific regulation of renal NDMA activity. Renal and hepatic NDMA-demethylase activities correlated positively with earlier studies on NDMA-induced mutagenesis and carcinogenesis.

Metastatic renal cell cancer and radical nephrectomy: identification of prognostic factors and patient survival

Between January 1, 1970 and December 31, 1980 (followup 2 years or more) 158 patients with histologically proved metastatic renal cell cancer and no prior therapy were seen. Statistical analyses identified variables that significantly influenced survival, including grade of the primary lesion (p equals 0.002), weight loss of more than 10 per cent (p less than 0.0001) and multiple versus single metastases (p equals 0.0001). Cell type, soft tissue versus bone metastasis, age, sex, site and size of primary lesion, and delay in the diagnosis did not influence survival significantly. Adjuvant nephrectomy markedly influenced survival only in patients with solitary metastasis, low grade primary tumor and weight loss of less than 10 per cent (p equals 0.06). Based on this analysis a score system was constructed to help predict survival and the impact of new forms of therapy in the future.

Treatment of advanced renal cell cancer with recombinant interferon alpha as a single agent and in combination with medroxyprogesterone acetate. A randomized multicenter trial

The response rates in metastatic renal cell cancer (RCC) after chemotherapy, hormonal treatment, or immunotherapy rarely exceed 15%. Recently, interferon alpha (IFN alpha) was used for treatment of this disease in several studies which also demonstrated response rates of 15%. In order to test whether IFN therapy combined with hormones would result in higher response rates we compared single agent IFN therapy with a combined therapy of rIFN alpha 2C plus medroxyprogesterone acetate (MPA) in a randomized multicenter trial. The rIFN alpha 2C (2MU) was given s.c. 5 times per week for 8-12 weeks and subsequently once weekly until week 48. In the combined treatment, 750 mg MPA was given p.o. daily until week 48 in addition to the IFN as described. The overall response rate in 93 evaluable patients was 5.4% corresponding to 2 complete and 3 partial responses. Median survival was 7 months in both treatment groups. These data confirm the ineffectivity of low IFN doses for treatment of RCC. The low response rate is not increased by addition of MPA to IFN. The analysis of other IFN studies suggests that not only IFN doses but also IFN sources may influence response rates in metastatic RCC.