David J. Straus

On the Use of Cause-Specific Failure and Conditional Failure Probabilities: Examples from Clinical Oncology Data

Abstract Nonparametric maximum likelihood estimation of the probability of failing from a particular cause by time t in the presence of other acting causes (i.e., the cause-specific failure probability) is discussed. A commonly used incorrect approach is to take 1 minus the Kaplan-Meier (KM) estimator (1 – KM), whereby patients who fail of extraneous causes are treated as censored observations. Examples showing the extent of bias in using the 1-KM approach are presented using clinical oncology data. This bias can be quite large if the data are uncensored or if a large percentage of patients fail from extraneous causes prior to the occurrence of failures from the cause of interest. Each cause-specific failure probability is mathematically defined as a function of all of the cause-specific hazards. Therefore, nonparametric estimates of the cause-specific failure probabilities may not be able to identify categorized covariate effects on the cause-specific hazards. These effects would be correctly identified ...

Low-dose compared with standard-dose m-BACOD chemotherapy for non-Hodgkin's lymphoma associated with human immunodeficiency virus infection

BACKGROUND Reduced doses of cytotoxic chemotherapy or standard-dose therapy plus a myeloid colony-stimulating factor decreases hematologic toxicity and its complications in patients with non-Hodgkins lymphoma associated with infection with the human immunodeficiency virus (HIV). However, the effect of reducing the doses of cytotoxic chemotherapeutic agents on clinical outcome is not known. METHODS We randomly assigned 198 HIV-seropositive patients with previously untreated, aggressive non-Hodgkins lymphoma to receive standard-dose therapy with methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) along with granulocyte-macrophage colony-stimulating factor (GM-CSF; n=94) or reduced-dose m-BACOD with GM-CSF administered only as indicated (n=98). RESULTS A complete response was achieved in 39 of the 94 assessable patients assigned to low-dose therapy (41 percent) and in 42 of the 81 assessable patients assigned to standard-dose therapy (52 percent, P= 0.56). There were no significant differences in overall or disease-free survival; median survival times were 35 weeks for patients receiving low-dose therapy and 31 weeks for those receiving standard-dose therapy (risk ratio for death in the standard-dose group=1.17; 95 percent confidence interval, 0.84 to 1.63; P=0.25). Toxic effects of chemotherapy rated grade 3 or higher occurred in 66 of 94 patients assigned to standard-dose therapy (70 percent) and 50 of 98 patients assigned to low-dose treatment (51 percent, P=0.008). Hematologic toxicity accounted for the difference. CONCLUSIONS As compared with treatment with standard doses of cytotoxic chemotherapy (m-BACOD), reduced doses caused significantly fewer hematologic toxic effects yet had similar efficacy in patients with HIV-related lymphoma. Dose-modified chemotherapy should be considered for most HIV-infected patients with lymphoma.

AIDS-related lymphoid neoplasia. The memorial hospital experience

The clinical features and laboratory results of 63 patients with or at risk for AIDS with lymphoid neoplasias seen from November 1980 through November 1986 are reviewed. Forty‐three had systemic non‐Hodgkins lymphoma (NHL), nine had primary large cell lymphomas of the brain, 11 had Hodgkins disease (HD), and one had plasmacytoma evolving to myeloma. Those with systemic NHL included 40 (93%) with intermediate or high‐grade histologies, 35 (81%) with advanced stage (III, IV), and 28 (65%) with extranodal disease at presentation (predominantly marrow and meninges). Overall survival was short (median, 10.5 months from diagnosis) with the majority of deaths attributable to AIDS‐related opportunistic infections (OI). However, 17 patients with diffuse NHL achieved a complete clinical remission, and nine now have been disease‐free for more than 1 year (median follow‐up, 28 months; range, 12 to 73 months). Early stage and lack of systemic symptoms were features associated with prolonged disease‐free survival. Primary brain NHL was a uniformly lethal manifestation of AIDS, being diagnosed at postmorten in seven of nine severely immunosuppressed homosexual men. As with NHL, a propensity towards advanced disease and extranodal involvement was also observed in HD, suggesting that the atypical clinical behavior of HD may be an additional epiphenomenon of AIDS. This experience tends to argue for the use of intensive therapy in at least some patients with AIDS‐related systemic NHL since it has resulted in a proportion of long‐term disease‐free survivors.

Autologous bone marrow transplantation for patients with poor-prognosis lymphoma.

Review of prognostic factors at Memorial Hospital in New York City has shown that adult patients with large-cell lymphoma (diffuse histiocytic lymphoma by Rappaport classification) who have high lactic dehydrogenase (LDH) and/or bulky mediastinal or abdominal disease are destined to do poorly with conventional combination chemotherapy, with a 2-year disease-free survival of about 20%. Patients who relapse after conventional combination chemotherapy have a similar poor prognosis. Thirty-one such patients with lymphoma were studied to evaluate the efficacy of intensive radiotherapy (hyperfractionated total body irradiation [TBI] [1,320 rad]), and cyclophosphamide (60 mg/kg/d for two days) followed by autologous bone marrow transplantation (ABMT). Our results show a disease-free survival advantage (P = .002) for 14 patients who underwent ABMT immediately after induction of remission with 79% surviving at a median follow-up 49.2+ months, compared with a median survival of 5.2 months for 17 patients administered ABMT while in relapse and/or after failing conventional treatment. Our results support the use of aggressive therapy as early treatment for patients with poor prognostic features.

Prognostic factors among 185 adults with newly diagnosed advanced Hodgkin's disease treated with alternating potentially noncross-resistant chemotherapy and intermediate-dose radiation therapy.

The initial promising results with alternating chemotherapy regimens (mechlorethamine, vincristine, procarbazine, and prednisone/doxorubicin, bleomycin, vinblastine, and dacarbazine [MOPP/ABVD]; lomustine, melphalan, and vindesine [CAD] plus MOPP plus ABV) combined with intermediate-dose radiation therapy (RT) have been sustained with further follow-up; 82.2% of patients (152 of 185) achieved a complete remission (CR), and overall survival is 71.7% +/- 4.4% at 8 years (median follow-up is 55 months among the survivors). No statistically significant differences were found in CR percentage, CR duration, or survival between stages IIB, IIIB, and IV patients. For that reason, stepwise Cox regression analyses to identify the important prognostic factors were performed on overall survival, tumor mortality, freedom from disease progression, and survival following disease progression. Pretreatment characteristics were also tested for association with the probability of achieving CR, CR duration, and death due to other causes. Characteristics that were consistently associated with an independently unfavorable prognosis were low hematocrit, high serum lactic acid dehydrogenase (LDH), age more than 45 years, inguinal node involvement, mediastinal mass greater than .45 of the thoracic diameter, and bone marrow involvement. Patients with two or more unfavorable characteristics were much more likely to fail treatment (median survival, 62.4 months) than those with none or only one unfavorable factor (greater than 95% survival). This striking difference between the low- and high-risk groups remained even if the comparison was restricted to patients less than or equal to 45 years of age. These results provide a basis for selecting the young patients at high risk of failure for more intensive initial treatment with either autologous bone marrow rescue or hematopoietic growth factors.

Treatment of acute lymphoblastic leukemia in adults: results of the L-10 and L-10M protocols.

Two successive protocols (L-10 and L-10M) employing multidrug induction therapy with vincristine, prednisone, and doxorubicin (Adriamycin) plus an intensive consolidation phase and maintenance program have led to a significant improvement in the prognosis of adult acute lymphoblastic leukemia (ALL). The complete remission (CR) rates for the 34 patients entered on the L-10 protocol and the 38 patients entered on the L-10M protocol were 85% and 84%, respectively. The median duration of remission has not yet been reached for either the L-10 (median follow-up, 5.5 years; range, 3.5-7.5 years) or the L-10M protocol (median follow-up, 2.5 years; range, 1-3.5 years). The median survival time has not yet been reached for the L-10M protocol. Central nervous system prophylaxis with intrathecal methotrexate alone was effective in preventing central nervous system relapse. An analysis of possible prognostic factors indicated that patients less than 25 years of age had a higher CR rate than older patients (p = 0.02). Patients with an initial leukocyte count below 15,000/microL experienced longer remissions than patients with a leukocyte count above 15,000/microL (p = 0.008), and patients who achieved CR within the first month of therapy were in remission longer than those requiring a longer time to achieve CR (p = 0.04). Patients with T cell ALL did not have a poorer prognosis than other patients treated on these protocols. The L-10 and L-10M protocols were well tolerated with minimal morbidity.

Prognostic factors in the treatment of human immunodeficiency virus-associated non-Hodgkin's lymphoma: analysis of AIDS Clinical Trials Group protocol 142--low-dose versus standard-dose m-BACOD plus granulocyte-macrophage colony-stimulating factor. National Institute of Allergy and Infectious Diseases.

PURPOSE The overall results of chemotherapy in human immunodeficiency virus (HIV)-associated non-Hodgkins lymphoma (NHL) have been poor. To define a subgroup of patients who may have a better outcome, an analysis of prognostic factors was performed of patients treated in AIDS Clinical Trials Group (ACTG) protocol 142, a phase III randomized trial of low-dose versus standard-dose methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone (m-BACOD) plus granulocyte-macrophage colony-stimulating factor (GM-CSF) for the treatment of patients with newly diagnosed HIV-associated NHL. MATERIALS AND METHODS The following baseline variables were included as potential predictors of survival among 192 patients who received treatment: age; intravenous drug use (IVDU); specific type of sexual contact as risk factors (homosexual, bisexual, or heterosexual contact); prior AIDS diagnosis; CD4 cell count; serum lactic acid dehydrogenase (LDH); histology; Karnofsky performance status (KPS); stage; B symptoms; race (white/nonwhite); nodal involvement; extranodal involvement; number of extranodal sites; specific sites: bone marrow, liver, kidney, lung, or gastrointestinal tract; and treatment arm (standard-dose m-BACOD/low-dose m-BACOD). RESULTS Age greater than 35 years, IVDU, stages III/IV, and CD4 cell counts less than 100/microL were adverse prognostic factors in multivariate analyses using the Cox proportional hazards model. The median overall survival for patients with none or one of the adverse factors was 46 weeks, with two was 44 weeks, and with three or four was 18 weeks. At 144 weeks, 29.5% of patients with none or one, 16.9% with two, and 0% with three or four factors were alive (P < .001). CONCLUSION Long-term survival can be achieved in approximately one third of patients with HIV-associated NHL with favorable characteristics.

Primary lymphoma of the liver

Nine adult white men ranging in age from 27 to 76 (mean, 55 years) were treated for primary hepatic lymphoma between 1972 and 1986 at the Memorial Sloan‐Kettering Cancer Center. Six patients presented with right upper quadrant or epigastric pain or discomfort, and three patients complained of fatigue and lethargy. Fever and night sweats were evident in two, and two patients had lost weight. One patient was asymptomatic; the liver mass was detected during the work‐up for cancer of the prostate. Seven patients on whom computerized tomography was performed all had solitary masses in the liver although in three of them tumor had extended into both lobes as noticed at surgery. One had additional porta hepatic lymph node metastasis. Eight patients underwent an exploratory laparotomy; four had hepatic resection, and four had wedge biopsies of unresectable liver tumor. One patient had a percutaneous needle biopsy of the liver. Eight patients received combination chemotherapy. Six patients are alive, five of whom are in initial complete remission. All three patients who died had persistent or recurrent disease in the liver. The results of therapy and surgery to date in these and in other cases in the literature are encouraging.

Accelerated hyperfractionated total-lymphoid irradiation, high-dose chemotherapy, and autologous bone marrow transplantation for refractory and relapsing patients with Hodgkin's disease.

PURPOSE To evaluate the feasibility and therapeutic effect of accelerated hyperfractionated total-lymphoid irradiation (TLI), high-dose chemotherapy, and autologous bone marrow transplantation (AuBMT) in patients with relapsing or chemotherapy-resistant Hodgkins disease (HD). PATIENTS AND METHODS Forty-seven patients with HD who either relapsed after chemotherapy (n = 19), or failed to respond (n = 28) to at least two regimens of combination chemotherapy were studied. No patient received prior radiation therapy (RT). Treatment started with reinduction with standard-dose chemotherapy, followed by involved-field irradiation (15 Gy) to areas of relapsed or persistent disease and TLI (20.04 Gy given in 1.67 Gy fractions three times per day for 4 days). Subsequently, patients received etoposide and high-dose cyclophosphamide, followed by infusion of unpurged autologous bone marrow. All surviving patients had a minimum follow-up duration of 1 year. The median follow-up duration for survivors was 40+ months, and the maximum follow-up duration was 80+ months. RESULTS Of the 47 patients treated, eight (17%) died of toxicity during the peritransplant period. Twenty-nine of the remaining 39 assessable patients (74%) attained a complete response (CR), while 10 remained with residual disease and progressed early after AuBMT. Four of the CR patients (14%) relapsed and 25 patients remained alive and free of disease. The actuarial disease-free survival (DFS) rate for the entire group at 6.5 years was 50%. Patients who received the protocol for relapsing HD had a significantly better DFS rate (79%) compared with patients treated for continuous refractory disease (DFS, 33%; P < .03). CONCLUSION Previously unirradiated patients with relapsing or chemotherapy-resistant HD who have exhausted conventional chemotherapy may still respond to an aggressive therapeutic approach consisting of accelerated hyperfractionated TLI, high-dose chemotherapy, and AuBMT rescue. This program offers a potential for long-term DFS to approximately one half of patients who would otherwise have a dismal prognosis with standard-dose salvage therapy.

Effect of ABVD chemotherapy with and without mantle or mediastinal irradiation on pulmonary function and symptoms in early-stage Hodgkin's disease

PURPOSE To evaluate the effect of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy alone and of ABVD with mantle or mediastinal irradiation (RT) on the pulmonary function of patients with early-stage Hodgkins disease. PATIENTS AND METHODS Between 1989 and 1993, 60 patients with clinical stage I to IIIA HD enrolled onto randomized trials at Memorial Sloan-Kettering Cancer Center (MSKCC) underwent prospective evaluation of pulmonary function. All patients received six cycles of ABVD, and 30 patients received mantle or mediastinal RT. Pulmonary function tests (PFTs) and symptom evaluation were conducted before, during, and after completion of chemotherapy and RT, and at various intervals thereafter. The median follow-up time was 30 months. RESULTS During chemotherapy, symptoms of cough and dyspnea on exertion developed in 32 of 60 patients (53%) and declines in pulmonary function occurred in 22 of 60 patients (37%). Discontinuation of bleomycin was necessary in 14 of 60 patients (23%). Following chemotherapy, there was a significant decline in median forced vital capacity (FVC) and diffusing capacity of carbon monoxide (DLCO). In patients who received mantle or mediastinal RT, there was a further decline in FVC following radiation therapy. At the most recent follow-up evaluation, five of 29 patients (18%) who received ABVD alone and nine of 30 (30%) who received ABVD and RT reported persistent mild pulmonary symptoms (P = .36), which did not significantly affect normal daily activity. CONCLUSION ABVD chemotherapy induced acute pulmonary toxicity that required bleomycin dose modification in a substantial number of patients. The addition of RT resulted in a further decrease in FVC; however, this did not significantly affect the functional status of patients.