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Purpose of Review: The knowledge base of malignant cell growth and resulting targets is rapidly increasing every day. Clonal theory is essential to understand the changes required for a cell to become malignant. These changes are then clues to therapeutic intervention strategies. Immune system optimization is a critical piece to find, recognize, and eliminate all cancer cells from the host. Only by administering (1) multiple therapies that counteract the cancer cell's mutational and externally induced survival traits and (2) by augmenting the immune system to combat immune suppression processes and by enhancing specific tumor trait recognition can cancer begin to be treated with a truly targeted focus., Recent Findings: Since the sequencing of the human genome during the 1990s, steady progress in understanding genetic alterations and gene product functions are being unraveled. In cancer, this is proceeding very fast and demonstrates that genetic mutations occur very rapidly to allow for selection of survival traits within various cancer clones. Hundreds of mutations have been identified in single individual cancers, but spread across many clones in the patient's body. Precision oncology will require accurate measurement of these cancer survival-benefiting mutations to develop strategies for effective therapy. Inhibiting these cellular mechanisms is a first step, but these malignant cells need to be eliminated by the host's mechanisms, which we are learning to direct more specifically. Cancer is one of the most complicated cellular aberrations humans have encountered. Rapidly developing significant survival traits require prompt, repeated, and total body measurements of these attributes to effectively develop multi-agent treatment of the individual's malignancy. Focused drug development to inhibit these beneficial mutations is critical to slowing cancer cell growth and, perhaps, triggering apoptosis. In many cases, activation and targeting of the immune system to kill the remaining malignant cells is essential to a cure.

Unlabelled: With the Food and Drug Administration and other worldwide regulatory authorities' approval of ipilimumab (Yervoy), sipuleucel-T (Provenge), nivolumab (Opdivo), and pembrolizumab (Keytruda), oncologic therapy has now moved into noncancer cell targets within the immune system. For many nonimmunologists, understanding how these vastly different therapies work to improve survival, like no other therapies have in the past, is a challenge. The present report reviews the normal function of the immune system, how cancers escape the normal immune system, and how these new therapies improve immune system reactions against cancers., Implications for Practice: Oncologists have tremendous experience with therapies that target the cancer cells. New biologic agents have been rapidly introduced recently that target not cancer cells, but the patient's immune cells. The mechanisms of action of these immune-based biologic agents are within the host immune system. To understand these new biologic therapies, basic knowledge of normal and abnormal immune function is essential. The present report explains the up-to-date basic immune normal and abnormal function and prepares the oncologist to understand how the new drugs work, why they work, and why there are associated adverse events., (©AlphaMed Press.)

A phase 1/2 clinical trial evaluating dosing, safety, immunogenicity, and overall survival on metastatic colorectal cancer (mCRC) patients after immunotherapy with an advanced-generation Ad5 [E1-, E2b-]-CEA(6D) vaccine was performed. We report our extended observations on long-term overall survival and further immune analyses on a subset of treated patients including assessment of cytolytic T cell responses, T regulatory (Treg) to T effector (Teff) cell ratios, flow cytometry on peripheral blood mononuclear cells (PBMCs), and determination of HLA-A2 status. An overall survival of 20 % (median survival 11 months) was observed during long-term follow-up, and no long-term adverse effects were reported. Cytolytic T cell responses increased after immunizations, and cell-mediated immune (CMI) responses were induced whether or not patients were HLA-A2 positive or Ad5 immune. PBMC samples from a small subset of patients were available for follow-up immune analyses. It was observed that the levels of carcinoembryonic antigen (CEA)-specific CMI activity decreased from their peak values during follow-up in five patients analyzed. Preliminary results revealed that activated CD4+ and CD8+ T cells were detected in a post-immunization sample exhibiting high CMI activity. Treg to Teff cell ratios were assessed, and samples from three of five patients exhibited a decrease in Treg to Teff cell ratio during the treatment protocol. Based upon the favorable safety and immunogenicity data obtained, we plan to perform an extensive immunologic and survival analysis on mCRC patients to be enrolled in a randomized/controlled clinical trial that investigates Ad5 [E1-, E2b-]-CEA(6D) as a single agent with booster immunizations.

The purpose of this study was to define the dose-limiting non-hematologic toxicity of carmustine, Ara C, cyclophosphamide and etoposide (BACE). Between October 1986 and March 1990, 37 patients with relapsed or refractory lymphoma received escalating doses of combination chemotherapy followed by autologous bone marrow transplant (ABMT). Twenty patients with Hodgkin's disease (HD) and 17 patients with intermediate or high grade non-Hodgkin's lymphoma (NHL) initially received conventional-dose therapy with either a 7 week course of modified MACOP-B or a single dose of cyclophosphamide (CY) at 2 g/m2 depending on prior therapy and response. Regardless of response, patients then received escalating doses of BACE, toxicity permitting. Ten patients obtained complete responses (CR) and 12 patients were partial responders (PR), CR+PR (75%) with modified MACOP-B and 7 (64%) patients obtained PR with CY. The maximum-tolerated dose (MTD) for BACE was determined to be carmustine 700 mg/m2, Ara C 1500 mg/m2, CY 150 mg/kg and etoposide 1500 mg/m2. When Ara C was escalated from 1500 mg/m2 to 3000 mg/m2 holding the other drugs at the prior doses, the next two patients died secondary to diffuse alveolar damage. Overall and event-free survivals are identical with 14 of 37 patients (38%) alive with a median follow-up of 61 months (range 38-79 months). Ten patients were treated at the MTD, none of whom died a toxic death and 3 (30%) are alive with a median follow-up of 42 months (range 38-52 months). We defined the MTD and BACE showing pulmonary toxicity to be the dose-limiting non-hematologic toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Chemotherapy-associated thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (C-TTP/HUS) is a condition involving thrombocytopenia, microangiopathic hemolytic anemia, and progressive renal dysfunction that develops in 2-10% of patients with a history of malignant neoplasms treated with certain chemotherapeutic agents. Pathogenesis of the disease may depend on the following: (1) generation of endothelial lesions in the kidney microvasculature, resulting from drug toxic effects and/or generation of small soluble circulating immune complexes (CIC), and (2) generation of autoantibodies and/or CIC that trigger aggregation and deposition of platelets around the lesions., Methods: Extracorporeal immunoadsorption treatment of plasma (PROSORBA columns, IMRE Corporation, Seattle, WA) to remove immunoglobulin G and CIC was evaluated in 55 patients for the potential to induce significant clinical benefits (increase in platelet count, decrease in hemolysis, stabilization of renal function) and longer survival., Results: Response to therapy was achieved in 25 of 55 patients examined. Response was associated with an estimated 1-year survival rate of 61%, as compared with an estimated survival rate of only 22% in those who did not respond (P = 0.0001). Patients whose malignant neoplasms were in complete or partial remission at the time of development of C-TTP/HUS had a significantly higher estimated 1-year survival rate (74%) as compared with a historic control group of patients receiving other treatments (22%, P = 0.0161). Clinical responses were correlated with normalization of serum levels of CIC and complement components C3c and C4. There were no side effects associated with 75% of treatments. Immunoadsorption therapy was associated with generally mild to moderate manageable side effects, such as fever, chills, nausea/vomiting, respiratory symptoms, pain, hypertension, and hypotension, which were reported in 25% of procedures., Conclusions: This multicenter study establishes protein A immunoadsorption as an effective and safe treatment for cancer chemotherapy-associated TTP/HUS, an otherwise fatal disease.

Thirty-seven HIV-infected homosexual men with thrombocytopenia (less than 100 x 10(9)/l) received protein A immunoadsorption treatments to remove platelet-sensitizing immunoglobulin (Ig) G and circulating immune complexes (CIC) from plasma. Patients received an average of six treatments each, consisting of 250 ml plasma over a 3-week period. Clinical improvement in hemorrhagic symptoms associated with substantial increase in platelet counts was achieved in 18 patients. These responses were maintained over a median follow-up period of more than 7 months in 14 evaluable patients who were not lost to follow-up (three patients relapsed in 2 weeks and one received another therapy). Generally, moderate transient treatment-related side-effects included fever, musculoskeletal pain, chills and nausea. A transient serum sickness-like reaction was observed in seven patients, leading to termination of treatment in two. Clinical responses were associated with significant decreases in levels of platelet-sensitizing Ig, including CIC. Stimulation of broadly cross-reactive anti-antigen-binding fragment [F(ab)2], antibodies contributed to these responses. Protein A immunoadsorption is an effective alternative treatment for HIV-associated thrombocytopenia.

Extracorporeal removal or modulation of circulating immune complexes (CIC) from plasma of animals and humans with malignant disease may be associated with induction of immune-mediated anti-tumor responses. Immunoadsorption columns containing heat-killed and formalin-fixed Staphylococcus aureus or staphylococcal protein A have been used for this purpose but treatments have often been associated with cardiopulmonary toxicity. Recently, an immunoadsorption device containing highly purified protein A covalently attached to a silica matrix (PROSORBA column) was used to treat 142 patients with refractory malignancies and 22 of 104 patients evaluated for anti-tumor response had objectively measurable reduction in tumor burden. In contrast to earlier experience with other devices, the procedures used in this trial were well tolerated and could be performed on an outpatient basis. The most common side effects observed among 1,306 treatments were chills (28% of treatments), low grade fever (28%), and musculoskeletal pain (16%). Side effects were mild to moderate and required no treatment or only symptomatic treatment. Treatment schedules were interrupted due to side effects for only six patients and there were no treatment-related deaths. Of 64 patients available for long-term follow-up evaluation (mean of 11 months), none exhibited evidence of long-term treatment-related side effects. None of the patient deaths in that period were associated with short or long-term treatment-related side effects. Protein A-silica (PROSORBA columns) can be used safely for development of further experimental treatments of malignant disease.

Two hundred Michigan hematologists-oncologists were sent a 34-item questionnaire designed to assess what patients should know at the time of giving consent to bone marrow transplant (BMT). Sixty-three (32%) responded to a single mailing and rated items on a 8-point scale, varying from 0 = no need to know to 7 = appreciation of consequences essential. The mean rating across items was 5.2, indicating that all items were important. Statistically, the items separated into three groups: (1) above average importance - 13 items; (2) average importance - 9 items; (3) below average importance - 12 items. Items of above average importance included the rationale for BMT and the collective risks and benefits of the process, including the patient's well-being post-transplant. Informed consent documents did not include 5/13 items of above average importance, yet 12/21 items of average and below average importance were included. Fourteen demographic variables were correlated with each item and none were significant, indicating that the ratings represent a broad consensus in the referring physician community as to what a patient should understand before consenting to BMT. The vast majority of referring physicians agreed that patients usually have an adequate understanding of BMT at the time of giving informed consent and that a fully informed patient is more likely to adhere to the treatment regimen.

A 53-year-old woman with a three-year history of recurrent stage IV diffuse aggressive lymphoma involving the nasopharynx presented with fever, chills, and the sudden onset of drainage of clear, colorless fluid from the left nostril. This woman had no history of trauma or physical activity that might increase intracranial pressure. Subarachnoid instillation of 111indium resulted in the accumulation of radioactivity in a cotton stint placed in the left nares, documenting cerebrospinal fluid rhinorrhea. Computed tomography of the head revealed bony erosion of the cribriform plate by lymphoma. Defervescence occurred in the patient 48 hours after treatment with antibiotics was begun, and systemic chemotherapy directed against the lymphoma resulted in resolution of the cerebrospinal fluid rhinorrhea within a month without surgical intervention.

Bone marrow transplantation is now recognized as one of the major advances in cancer therapy occurring in the past three decades. The USAF Medical Corps recognized the future need and potential for bone marrow transplantation programs and began sponsored physician training in the late 1970's. Additionally, a bone marrow transplantation unit was designed and incorporated into the new physical plant of Wilford Hall USAF Medical Center (WHMC). The first human autologous bone marrow transplantation at WHMC was performed 6 December 1982. Since then, approximately 100 patients have undergone the procedure. As bone marrow transplantation procedures have become more extensively applied and accepted as the standard of care for selected diseases, the need for the Department of Defense (DOD) military-medical complex to provide allogeneic transplantation services has grown tremendously. This program brings the most up-to-date therapy for the treatment of many cancers to the USAF and DOD and provides the avenues for further advances in cancer therapy in the decades to come. In addition, this program has exciting potentials in the chemical warfare defense area of battlefield medicine.

Therapeutic intervention in a course of illness, while producing the desired result, also may have some adverse long-term effects on the patient. Second malignancies are one of the known complications of therapy. The treatments of gynecologic cancers by surgery, irradiation and chemotherapy have been associated with subsequent neoplasms. Care must be exercised in associating previous therapy and a subsequent malignancy. "Naturally" occurring second cancers must be separated from those which are iatrogenic. Associations in the literature have been made involving malignancies as a sequelae of prior gynecologic therapy. The use of normal skin from the thigh to fabricate an artificial vagina has resulted in more squamous cell carcinomas than expected. Alkylating agents used in the treatment of ovarian cancer and other diseases have been shown to lead to an increased risk of leukemia. Irradiation therapy, however, has not yet been shown to be related to leukemia in cervical cancer patients. The incidence of lymphoma and uterine, urinary bladder and colon carcinomas has been associated with prior irradiation for gynecologic disease. The literature regarding the therapeutically induced risk factors in gynecologic therapy is reviewed and areas of our knowledge that require more investigation are identified.

Circulating immune complexes (CIC) are known to be present in cancer patients and are responsible for much of the cancer-associated immunosuppression. Removal or modulation of these "blocking factors" can reverse the immunosuppression. Protein A from Staphylococcus aureus has the unusual property of binding to CIC with high avidity. Use of protein A as an immunoadsorbent in extracorporeal immunotherapy affinity columns has resulted in antitumor and antiviral responses in animals. Our group developed a multicenter trial to assess toxicity and antitumor response with this biologic response modifier alone. Overall, 24% (21 of 87 patients) had objective tumor regressions including both partial responses (PR) and less than PR. No complete responses (CR) were observed. Responses were observed in acquired immune deficiency syndrome (AIDS)-related Kaposi's sarcoma (six of 17 PR; two of 17 less than PR; overall, 47%), breast adenocarcinoma (five of 22 PR; three of 22 less than PR; overall response, 36%), colon adenocarcinoma, (one PR, one less than PR; overall response, 11%), and non-oat cell lung carcinoma (two of seven less than PR). The procedure was well tolerated and could be performed on an outpatient basis. No adverse reaction was observed in 735 of 1,113 treatments (66%). The most common adverse effect was an "influenza-like" syndrome consisting of fever and chills. Pain was present in 12% of the patients. There were no study-related deaths. Serum IgG and CIC levels did not statistically change due to therapy in responding or nonresponding patients. Complement levels remained within the normal range. Liver and renal tests remained stable throughout the study. In summary, protein A immunoadsorption of plasma is well tolerated in the outpatient clinic, has demonstrated antitumor activity in resistant solid tumors, and functions as a biologic response modifier.

The use of histocompatability antigen (HLA)-matched platelets has been advocated for the support of thrombocytopenic cancer patients. We randomized 78 newly diagnosed cancer patients prospectively (before thrombocytopenia) to receive either HLA-matched or mismatched single-donor platelet transfusions. Three hundred forty-one platelet transfusions were given for 80 separate episodes of therapy-induced thrombocytopenia in 33 patients. Forty-five patients receiving intensive chemotherapy did not develop significant (less than 20,000 platelets/mm3) thrombocytopenia and did not receive a platelet transfusion. No marked difference was observed between the matched and mismatched groups in regard to number of total platelet transfusions per patient (median, 3 vs. 5, respectively; P = 0.076), number of platelet transfusions per episode (median, 3.0 vs. 3.5, respectively; P = 0.28), or days between transfusions (median, 2 vs. 2, respectively, P greater than 0.4). Bleeding episodes, although rare, tended to be of increased severity in the mismatched group. Febrile patients receiving mismatched platelets tended to have a lower posttransfusion increment increase than their nonfebrile counterparts (P = 0.068), although a similar trend could not be demonstrated between febrile and nonfebrile patients who received matched platelets (P = 0.22). Patients treated as outpatients had significantly higher posttransfusion increments than when transfused as inpatients when they were given mismatched platelets (P less than 0.0005). Development of antiplatelet antibody did not appear to affect response to platelet transfusions. Only one patient developed sustained high-level antibody titers. In patients where thrombocytopenia was significant, the transfusion of HLA-matched platelets did not appear to offer a significant advantage. However, HLA-matched platelet transfusions tended to be associated with higher posttransfusion increments in febrile patients and a trend toward fewer severe bleeding episodes. A multi-institution trial containing a large number of patients is needed to evaluate trends observed in this study.

Protein A, a naturally occurring Staphylococcus aureus cell surface protein, has the unusual property of binding circulating immune complexes and immunoglobulin G with high avidity. CIC have played a major role in cancer-associated immunosuppression. Thus, removal of the immunosuppressive agents, ie, the CIC, may lead to a modulation of the immunosuppression and a liberation of the immune system to perform an antitumor effect. In animal studies, protein A has been used in extracorporeal immunoadsorption columns and treatments have resulted in tumor shrinkage and antiviral responses. Our group developed a multicenter clinical trial to assess toxicity and antitumor responses with this biologic response modifier alone. This is an update of our original trial. We have now treated 142 patients for a total of 1,306 treatments. The patients consisted of 74 males and 68 females. Their age ranged from 7 to 83 years, with a mean of 50 years. The Karnofsky performance index values ranged from 40 to 95, with a mean of 80. Patients who received seven or more treatments were considered eligible for tumor response assessment, and all patients with one or more treatments were eligible for toxicity assessment. Thus, there were 101 patients eligible for tumor response and 142 eligible for toxicity response. The total response rate was 22 patients or 21.8% (partial remission [PR], 12 patients, 12%; less than PR, 10 patients, 10%). Response rates were similar in the 13 treatment centers. Toxicity was assessed in 142 patients. One thousand three hundred six treatments were assessed for treatment toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Perfusion of plasma from tumor-bearing animals over Staphylococcus aureus with membrane-bound protein A has resulted in significant tumor shrinkage. Similar therapy has now been given to 16 patients by three methods. No tumor responses have been observed. Five patients were treated with perfusion over fixed and killed S. aureus Cowan I. Cardiovascular and respiratory toxicity was excessive and appeared to be related to volume and rate of plasma infused. Eight patients were treated with perfusion of autologous plasmas over protein A-collodion-charcoal. Doses of plasma ranged from 50 to 450 ml. No toxicity was noted. Three patients have been treated with perfusion over protein A-silica. Toxicity in two resembled that seen in the S. aureus trials, although it was not as severe. We conclude that the toxicity of this therapy can be life-threatening, and human trials should be undertaken with caution.

Ten tumor-bearing dogs were treated with passage of autologous plasma over fixed Staphylococcus aureus Cowan strain I. Five similar dogs were treated identically except for the exposure to S. aureus. These animals have been assessed to identify positive and negative prognostic variables for response. Nonresponder treated animals had significantly larger chest wall tumor bulk than did the responder and control groups (P less than .01). Responder animals had fewer initial circulating immune complexes than did the nonresponders, though each group had similar reductions in immune complexes with therapy. Nonresponder animals had smaller volumes of plasma processed per kilogram of body weight per procedure than did controls (P = .016), whereas responder and control animals had similar volumes processed per kilogram of body weight per procedure (P = .84). These data suggest that the response observed in our original series was significantly related to the larger amount of plasma treated per procedure and suggest that a factor may be eluted from the S. aureus cartridge that mediates this response.

Human bone marrow was harvested from surgically resected bones of 25 patients and was tested for the presence of mature T cells. An average of 6.5% (+/- 1.2% SE) of nucleated bone marrow cells formed spontaneous rosettes with sheep red blood cells. Functional T cells in bone marrow were also identified by characteristic responses to alloantigens and the T cell mitogens concanavalin A (Con A) and phytohemagglutinin (PHA). The ability of three monoclonal antibodies (OKT.3, Lyt-3, and (Leu-1) to lyse peripheral T cells in the presence of rabbit complement was examined. All three reagents were found to be specifically lytic for mature T cells in peripheral blood. One reagent (Leu-1) was selected for use in depletion of T cells in human bone marrow. Seven of 10 experiments performed showed sufficient T cell responses to be evaluable. In all of these experiments, a marked reduction of T cells and T cell functions was observed. On the average, E rosettes were reduced 89.2% (+/- 3.0% SE) below medium controls while the mean PHA, Con A, and mixed lymphocyte culture (MLC) activity were completely eliminated to levels below background. In four experiments, colony-forming units (CFU-GM) in bone marrow were assayed following treatment with Leu-1 and showed a mean increase of 194% (+/- 32% SE) over medium controls. Since mature T cells are thought to be responsible for graft-versus-host disease in allogeneic bone marrow transplantation, this method of T cell depletion may be useful for preparing marrow for human bone marrow transplants.

Colon carcinoma, the second leading cause of cancer-related deaths in the United States, is resistant to chemotherapy in a large majority of cases. Single-agent and combination chemotherapy have failed to prolong survival. New approaches are clearly needed. In experimental models, a steep dose-response curve for colorectal cancer has been demonstrated using various agents. The hematopoietic toxicity of high-dose therapy with these drugs can be circumvented by autologous bone marrow transplantation. We investigated the use of high-dose melphalan with autologous bone marrow rescue in 20 patients with metastatic colon carcinoma. Each patient received melphalan, 180 mg/m2 intravenously (IV), followed eight hours later by bone marrow infusion. Median duration of granulocytopenia (less than 500 neutrophils/microL) was twelve days (range, 5 to 35 days), while transfusion-dependent thrombocytopenia (less than 20,000 platelets/microL) had a median duration of eight days (range, 3 to 23 days). Time to bone marrow engraftment was not affected by prior 5-fluorouracil therapy. Nausea and vomiting occurred in 14 patients but was generally short lived. Mild stomatitis, esophagitis, and diarrhea were common. Severe gastrointestinal (GI) side effects did not occur. One treatment-related death occurred secondary to intramural tumor necrosis, which resulted in massive lower GI bleeding. Complete responses were observed in three patients (15%) and partial responses in six patients (30%), for an overall response rate of 45%. Median survival was 198 days in this group of patients with extensive disease. High-dose melphalan therapy for metastatic colon carcinoma, when used with autologous bone marrow transplantation, appears to achieve a high response rate with tolerable toxicity. Further investigation is needed to define the role of this therapy in the care of advanced colon carcinoma.

Etoposide (VP-16-213) has been used in the treatment of many solid tumors and hematologic malignancies. When used in high doses and in conjunction with autologous bone marrow transplantation, this agent has activity against several treatment-resistant cancers including malignant glioma. In six of eight patients (75%) who we treated for recurrent or resistant glioma, sudden severe neurologic deterioration occurred. This developed a median of 9 days after initiation of high-dose etoposide therapy. Significant clinical manifestations have included confusion, papilledema, somnolence, exacerbation of motor deficits, and sharp increase in seizure activity. These abnormalities resolved rapidly after initiation of high-dose intravenous dexamethasone therapy. In all patients, computerized tomographic (CT) brain scans demonstrated stability in tumor size and peritumor edema when compared with pretransplant scans. This complication appears to represent a significant new toxicity of high-dose etoposide therapy for malignant glioma.

Hypercalcemia has been infrequently associated with Hodgkin's disease. When seen, most cases have been attributable to skeletal invasion by disease. Herein is described a 40-year-old man with a 15-year history of Hodgkin's disease. Each of four disease recurrences was heralded by hypercalcemia occurring in the absence of bone disease or elevation of parathyroid hormone levels. Marked elevations of 1,25-dihydroxyvitamin D levels were observed that paralleled his disease course and response to therapy. The repetitive association of hypercalcemia with an elevation of 1,25-dihydroxyvitamin D in this case provides further evidence of lymphoma-associated production of this vitamin.

A new intensive four drug combination chemotherapy regimen, termed PVeBV, consisting of cis-platinum, vinblastine, bleomycin, and VP-16, was administered to six previously untreated patients with poor prognosis advanced nonseminomatous testicular cancer and to four patients who had relapsed on primary platinum based regimens. The cis-platinum was administered in 250 ml of 3% saline at twice the dose (40 mg/m2 IV days 1-5 every three weeks) used in other treatment schedules. All six previously untreated patients achieved a complete remission. Four achieved a complete remission with three cycles of PVeBV while the other two patients achieved a complete remission with an additional cycle of cisplatinum and VP-16 at 200 mg/m2 IV X five followed by autologous bone marrow infusion. All four relapsed patients responded to PVeBV (two complete remissions and two partial remissions). There were no deaths associated with PVeBV therapy; however, myelosuppression was severe. There has been no renal toxicity (other than hypomagnesemia) observed with 35 cycles of high-dose platinum therapy in previously untreated patients. These results indicate that PVeBV is a promising chemotherapy regimen for the treatment of poor prognosis testicular cancer patients. Furthermore, it appears that cis-platinum can be administered at higher doses than previously used without an increase in renal toxicity if administered in hypertonic saline. The high-dose cis-platinum schedule, as used in PVeBV, warrants evaluation in other tumors which respond to standard-dose platinum therapy.

Both antibodies and circulating immune complexes (CIC), which bind to platelets and induce the destruction and clearance of platelets by the reticuloendothelial system, are found in patients with human immunodeficiency virus (HIV) and immune thrombocytopenic purpura (ITP). IgG and CIC were removed from patients' plasma by extracorporeal immunoadsorption using protein A-silica columns (PROSORBA columns). Of the 36 HIV-positive ITP patients treated, 29 received more than one treatment and were evaluated for response. Sixteen patients showed more than a 50% increase in their platelet counts. Platelet-associated IgG (PAIgG) and/or platelet-directed IgG and CIC were elevated in all patients. After four to eight treatments, 16 of 29 patients showed a 170% to 430% increase in platelet counts. A decrease in CIC and PAIgG was noted in responding patients. The median duration of response to date was 8 to 12 months. This treatment was associated with immune modulation and the development of an anti-F (ab')2 antibody response. The antibody functions by complexing with both platelet-binding IgG and CIC, neutralizing their binding capacity for platelets and enhancing their clearance from the circulation. Nine patients with mitomycin-C-induced hemolytic uremic syndrome (HUS) were also treated with PROSORBA columns. Pretreatment platelet counts were markedly reduced while a definite increase in platelet counts was observed upon completion of therapy. There was a decrease of hemolysis and stabilization of renal function in three patients. PROSORBA column treatment has demonstrated marked activity against both HIV-ITP and HUS, and has successfully freed patients from the bleeding diathesis associated with these syndromes.