Biomedical subjects

R S Cox

Publications and source records attributed to R S Cox.

At least 73 records · Page 4Linked to original sources

PubMed1986

Rhabdomyosarcoma: the Stanford experience using a TNM staging system.

Seventy-four patients with rhabdomyosarcoma were initially staged according to the Intergroup Rhabdomyosarcoma Study (IRS) grouping classification and then retrospectively using a TNM staging system based on the initial clinical extent of disease. The TNM system includes T1, tumor confined to site or organ of origin; T2, regional extension beyond the site of origin; N0, normal lymph nodes; N1, lymph nodes containing tumor; M0, no evidence of metastases; and M1, distant metastases. All patients received combination chemotherapy, and more than 90% received radiation therapy as part of their initial treatment program with curative intent. Fifty-three of 74 patients (72%) were group III according to the IRS system, indicating unresectable or gross residual tumor. A more uniform distribution was achieved using the TNM system. Freedom from relapse (FFR) was 43% and the actuarial survival rate was 47% for the entire study group at 10 years. All but one relapse occurred within 3 years of initial diagnosis, and only three of 38 relapsed patients were salvaged. All TNM stage I patients are surviving disease free. Among patients having stages II, III, and IV disease by the TNM system, FFR was 53%, 26%, and 11%, and the survival rates were 47%, 36%, and 33%, respectively. Thirty-two of 74 patients (43%) had evidence of lymph node involvement at presentation, and 28 (88%) of these had primary lesions that extended beyond the site of origin (T2 primary). Histologic subtype and primary site had little impact on outcome in a multivariate analysis, and T stage was identified as the single most significant covariate correlated with survival; a model composed of both T stage and M stage was the best one for predicting relapse. The presented data support a study using a prospectively assigned TNM staging system based on the initial clinical extent of disease for use in future therapeutic trials.

Adolescent↗

PubMed1986

Factors predicting survival in adults with stage I and II large-cell lymphoma treated with primary radiation therapy.

The records of 148 consecutive patients with Ann Arbor stage I and II large-cell lymphoma treated with primary radiation therapy with or without adjuvant chemotherapy were analyzed retrospectively for pretreatment prognostic variables and results of treatment. For patients treated with radiation to fields on one side of the diaphragm, the 5 year freedom-from-relapse rate was 25% and the survival rate was 35%, but for those given additional transdiaphragmatic radiation or for those given radiation plus adjuvant chemotherapy, the rates were both approximately 67%. In a multivariate analysis, the only significant pretreatment prognostic variables were the number of sites of involvement and bulk of disease, with relapse as the endpoint. For patients treated with radiation to both sides of the diaphragm or with radiation plus adjuvant chemotherapy, the 5-year freedom-from-relapse rate was 82% for the group with a favorable prognosis (with less than three sites of involvement and a mass size of less than 10 cm) and 55% for those with an unfavorable prognosis.

Actuarial Analysis↗

PubMed1985

Combination of external beam irradiation and multiple-site perineal applicator (MUPIT) for treatment of locally advanced or recurrent prostatic, anorectal, and gynecologic malignancies.

We have devised a single after-loading applicator, the Martinez Universal Perineal Interstitial Template (MUPIT), which has been used in combination with external beam irradiation to treat 104 patients with either locally advanced or recurrent malignancies of the cervix, vagina, female urethra, prostate, or anorectal region. Twenty-six patients treated for prostate cancer are excluded because of their short follow-up. Local failure developed in 13 of the 78 remaining patients (16.6%)--major complications developed in 4 patients (5.1%). Follow-up has been 1 year to 7 1/2 years; 60/78 patients have been followed for more than 2 years. All local recurrences and complications occurred before 18 months. The device consists of two acrylic cylinders, an acrylic template with an array of holes that serve as guides for trocars, and a cover plate. In use, the cylinders are placed in the vagina and/or rectum or both and then fastened to the template so that a fixed geometric relationship among the tumor volume, normal structures, and source placement is preserved throughout the course of the implantation. Appropriate computer programs have been developed to calculate the dose from these implants. The advantages of the system are (a) greater control of the placement of sources relative to the tumor volume and critical structures, as a result of the fixed geometry provided by the template and cylinders, and (b) improved dose-rate distributions obtained by means of computerized optimization of the source placement and strength during the planning phase. We conclude that the local control rate (83.4%) with low morbidity (5.1%) achieved with the combination of external beam irradiation and MUPIT applicator in these patients with locally advanced malignancies represents an improvement over previous published results with other applicators.

Adenocarcinoma↗

PubMed1985

The potential benefits of therapeutic splenectomy for patients with Hodgkin's disease and non-Hodgkin's lymphomas.

Thirty-four patients with Hodgkin's disease and non-Hodgkin's lymphoma underwent therapeutic splenectomies to improve hematologic tolerance for chemotherapy. The mean age was 40 years; there were 16 males and 18 females. Fourteen had Hodgkin's disease, 19 had non-Hodgkin's lymphoma, and 1 had malignant histiocytosis. Nineteen had palpable splenomegaly, 19 had marrow involvement and 20 had splenic involvement by lymphoma. The following data were analyzed before and after splenectomy: mean white blood cell count (WBC) and platelet count on planned first day of cycle, delay ratio of chemotherapy delivery and percent maximal dose rate. Thirteen patients had non-Hodgkin's lymphoma, splenomegaly and positive bone marrow and showed significant benefit in all of the aforementioned parameters. Of the patients with prior irradiation, only those who completed their radiation greater than six months prior to splenectomy showed benefit. Ten patients had Hodgkin's disease, negative bone marrow and no splenomegaly. This group showed significant improvement in mean platelet count but more limited benefit in delay ratio and percent maximal dose rate. Thus, selected patients with lymphoma who are experiencing delays in chemotherapy because of poor count tolerance may benefit from splenectomy.

Adolescent↗

PubMed1985

Late relapse among patients treated for Hodgkin's disease.

Of 1360 consecutive patients with Hodgkin's disease treated at Stanford University, 1312 patients (96%) had complete remission, but 424 patients had a relapse. Fifty-five patients had relapses 36 months or more after completion of therapy. The actuarial risk of relapse in patients disease-free 3 years after therapy was 12.9%. The occurrence of late relapse was significantly related to stage I disease and nodular sclerosis histologic subtype. Late relapse was detected in 88% of patients by history, physical findings, or chest radiographs. Most patients with stage III and IV disease had late relapses in previously irradiated nodes or extranodally, but patients with stage I and II disease had late relapses primarily in unirradiated nodes. Disease-free survival after salvage therapy for late relapse was similar to that seen after treatment of earlier relapse. Prolonged surveillance of patients for late relapse is necessary after treatment of patients with Hodgkin's disease.

Adolescent↗

PubMed1985

Radiotherapy of prostatic carcinoma: long- or short-term efficacy (Stanford University experience).

Results of a study that began at Stanford in 1956 demonstrate that long-term, disease-free survival can be achieved following appropriate irradiation in patients with prostatic carcinoma. However, the investigation has also uncovered several powerful prognostic indicators, such as the extent of anatomic involvement, histologic pattern, particularly as described by Gleason; and presence or absence of lymphnode metastases. To illustrate the importance of these parameters, the author presents data that correlate survival with the anatomic extent of the primary tumor and the Gleason pattern scores. Of the staged patients, 64 have been subjected to post-therapeutic biopsy of the prostate 18 months or more following therapy. A correlation also seems to exist among clinical stage, lymph node involvement, and subsequent biopsy status. The implication of this finding in the development of more aggressive therapeutic approaches will be discussed.

Actuarial Analysis↗

PubMed1984

Thyroid dysfunction after radiotherapy in children with Hodgkin's disease.

Thyroid function was measured in 119 children, 16 years of age or less, after radiotherapy (XRT) for Hodgkin's disease. Thyroid abnormalities developed in 4 of 24 children (17%) who received 2600 rad or less, and in 74 of 95 children (78%) who received greater than 2600 rad to the cervical area, including the thyroid. The abnormality in all but three (one with hyperthyroidism and two with thyroid nodules) included the development of elevated levels of thyroid stimulating hormone (TSH). Age, sex, and administration of chemotherapy were not significant factors in the development of thyroid dysfunction. All children had lymphangiograms (LAG) and no time relationship was noted between thyroid dysfunction and LAG-XRT interval. The mean interval from radiotherapy to documented thyroid dysfunction was 18 months in the low-dose group and 31 months in the high-dose group, with most patients becoming abnormal within 3 to 5 years. Of interest was a spontaneous return of TSH to within normal limits in 20 children and substantial improvement in another 7. This study confirms the occurrence of dose-related occult hypothyroidism in children following external irradiation of the neck.

Adolescent↗

PubMed1984

The effect of postoperative and primary radiation therapy on delivered dose of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) chemotherapy in breast cancer.

The dose of adjuvant chemotherapy for breast cancer may be an important factor in the success of the treatment program. In a retrospective analysis, the authors determined whether patients who were irradiated either postoperatively (N = 29) or as part of primary treatment (N = 13) received a lower dose of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) chemotherapy than patients who were not irradiated (N = 42). The 84 evaluable patients received either cyclical or weekly CMF. Radiation therapy included the chest wall or breast and regional lymph nodes. The mean percentage of maximum chemotherapy dose delivered (59.9% versus 73.5%; P less than 0.001), mean percent prescribable or theoretical maximum dose (83.1% versus 91.3%; P less than 0.001), and mean leukocyte count (3.9 versus 4.5; P less than 0.01) during therapy were statistically significantly lower in irradiated patients. The lower delivered chemotherapy dose in irradiated patients was not related to the radiation dose to the thoracic spine. The authors conclude that radiation therapy to the chest wall or breast and regional lymph nodes reduces the dose of adjuvant CMF that can be delivered.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1984

A multiple-site perineal applicator (MUPIT) for treatment of prostatic, anorectal, and gynecologic malignancies.

Recently, transperineal interstitial-intracavitary applicators have been used to treat locally limited and advanced perineal and gynecologic malignancies. We have developed a single afterloading applicator, referred to as the "MUPIT" (Martinez Universal Perineal Interstitial Template), which with its prototypes has been utilized to treat 78 patients with malignancies of the cervix, vagina, female urethra, perineum, prostate, and anorectal region. The device basically consists of two acrylic cylinders, an acrylic template with a predrilled array of holes that serve as guides for trocars, and a cover plate. Some of the guide holes on the template are angled outward to permit a wide lateral coverage without danger of striking the ischium. The cylinders have an axial hole large enough to pass a central tandem or a suction tube for the drainage of secretions. Thus, the device allows for the interstitial placement of 192Ir ribbons as well as the intracavitary placement of either 137Cs tubes or 192Ir ribbons. In use, the cylinders are placed in the vagina and rectum and then fastened to the template, so that a fixed geometric relationship among the tumor volume, normal structures, and source placement is preserved throughout the course of the implantation. Hollow, closed-end, stainless steel trocars are then inserted through the guide holes that produce optimal coverage of the treatment volume. Appropriate computer programs also have been developed on a minicomputer for the corresponding dose-rate computations. These programs run with sufficient speed that they may be used for both the planning of the source placement beforehand and the computation of the actual dose-rate distribution obtained. The advantages of the system are (1) greater control of the placement of sources relative to the tumor volume and critical structures owing to the fixed geometry provided by the template and cylinders, and (2) improved dose-rate distributions obtained by means of computer-assisted optimization of the source placement and strength during the planning phase.

Anus Neoplasms↗

PubMed1984

Lymphocyte predominant Hodgkin's disease: clinical presentation and results of treatment.

The records of 59 patients with lymphocyte predominant Hodgkin's disease (LPHD) evaluated and treated at Stanford University Medical Center between 1963 and 1983 were reviewed. Of these 59 patients, 92% are alive at 10 years following treatment, 78% are relapse-free, and none have died of Hodgkin's disease. Compared with the other histologic subtypes of Hodgkin's disease, LPHD presents more frequently as stage I or II disease (78% vs. 55%) and less frequently with constitutional symptoms (7% vs. 32%). Despite these factors, there is no statistically significant difference in either survival or freedom-from-relapse (FFR) between the histologic subtypes when comparisons are made on a stage-for-stage basis. Analysis of sites of presentation and relapse reveals that LPHD rarely involves intrathoracic structures. Patients with C.S. I disease presenting in inguinofemoral or high cervical lymph nodes do not require staging laparotomy as none of these patients were upstaged by surgery. Patients with stage I disease involving high cervical lymph nodes may be treated with limited field irradiation employing fields no more extensive than a mantle and Waldeyer's ring field, as no relapses have been seen in such patients treated in this fashion. Although limited field irradiation was used successfully for LPHD presenting in other localized sites, inadequate patient numbers preclude assessment of this treatment for those clinical presentations.

Adolescent↗

PubMed1984

Gas-chromatographic determination of mexiletine with a nitrogen-selective detector.

The authors present a procedure for the determination of mexiletine in serum. The drugs are extracted under basic conditions into n-heptane/isobutanol (96/4 by vol) and then extracted again into 1 mol/L H2SO4. The acidic solution is made basic with sodium hydroxide, reextracted with diethyl ether, and the extract evaporated. The residue is redissolved in ethanol and analyzed by gas chromatography with a nitrogen-selective detector. By use of two internal standards, diphenhydramine and p- chlorodisopyramide , concentration and instrument response are related linearly from 500 micrograms/L to 4.0 mg/L. Interferences from other drugs also are eliminated by using two internal standards. Within-run precision (CV) was 5% at the 1 and 2 mg/L concentration: between-run precision was 10% and 5% at those respective concentrations. Interference studies indicate that most commonly prescribed basic drugs will not interfere with this procedure.

Chromatography, Gas↗

PubMed1984

Childhood Hodgkin's disease: patterns of relapse.

One hundred seventy-nine consecutive children with Hodgkin's disease seen at Stanford University Medical Center between the years 1961-1980 have been analyzed for survival and freedom-from-relapse as a function of clinical versus laparotomy staging as well as primary treatment modalities. Of laparotomy-staged patients, 86% are alive at 10 years after primary radiation with chemotherapy reserved for relapse, as compared with 90% managed by planned combined modality therapy (p = 0.62). Patients who were clinically staged and managed with primary radiation have only a 69% survival (p = 0.05). A favorable subgroup of patients with lymphocyte-predominant Hodgkin's disease experienced a low relapse rate regardless of primary treatment modality. Patterns of relapse in clinically staged patients reflect understaging, with most relapses in distant, nonirradiated sites, whereas the less frequent relapses in laparotomy-staged patients usually reflect regional recurrence. It is concluded that laparotomy staging is highly desirable to allow greatest flexibility in optimizing individual therapy. Routine combined modality treatment for all patients would overtreat certain favorable subgroups, who can be managed more conservatively as long as the information derived from surgical staging is available. For young children, in whom bone growth issues are paramount, combined modality treatment using low-dose radiation is recommended. For older children and adolescents, where concerns over chemotherapy-related leukemogenesis and infertility are more important than height considerations, radiation alone may be used for stages I-IIIA with equal overall success.

Adolescent↗

PubMed1984

Increased incidence of acute nonlymphocytic leukemia following therapy in patients with small cell carcinoma of the lung.

A group of 158 patients with small cell carcinoma of the lung were followed for 174.5 person-years of observation to determine the risk of acute leukemia. Three cases of acute nonlymphocytic leukemia were observed at 2.3, 2.7, and 3.0 years. The relative risk of developing leukemia was 316 (95% confidence limit, 76-818) and the actuarial risk was 25% +/- 13% at 3.1 years. The relative risk for leukemia was significantly increased in these patients (p less than 0.0001).

Adult↗

PubMed1984

The role of radiation therapy in the management of stage III follicular lymphomas.

Between 1961 and 1982, 66 patients with stage III follicular small cleaved (FSC) and follicular mixed small cleaved and large cell (FM) lymphoma were treated at Stanford University. Treatment consisted of total-lymphoid irradiation (TLI) to a total dose of about 4,000 rad in 61 patients or whole-body irradiation (WBI) followed by boost irradiation to sites of involvement in five patients. In addition, 13 patients treated with TLI received adjuvant chemotherapy, consisting of six cycles of cyclophosphamide, vincristine, and prednisone (CVP). Median follow-up was 9.6 years. Kaplan-Meier actuarial survival at five, ten, and 15 years was 78%, 50%, and 37%, respectively. Freedom from relapse at five and ten years was 60% and 40% with no relapses after ten years. In a prospective randomized study of 16 patients who all underwent staging laparotomy comparing TLI with or without adjuvant chemotherapy with CVP, there was no significant difference in either survival or freedom from relapse between the two groups. Patients with limited stage III disease (without B symptoms, less than five sites of involvement, and maximum size of disease less than 10 cm) had an excellent prognosis with a 15-year survival and freedom from relapse of 100% and 88%, respectively. Radiation therapy may be a potentially curative modality in patients with stage III follicular lymphomas.

Actuarial Analysis↗

PubMed1984

Hodgkin's disease in patients over sixty years old.

Fifty-two patients 60 to 75 years of age were treated for Hodgkin's disease at Stanford University between 1968 and 1980. Adequate staging was defined as including a lymphogram and staging laparotomy for stage I to III and a positive bone marrow or liver biopsy or other evidence of diffuse involvement of extralymphatic tissues for stage IV. Adequate treatment was defined as subtotal lymphoid irradiation for pathologic stages I to IIA; total lymphoid irradiation for stages IIB to IIIA; and chemotherapy with or without irradiation for stages IIIB to IV. Twenty-four patients (46%) had advanced disease (IIIB to IV). Those patients who received appropriate treatment had a median survival of only 39 months. Of the 28 patients with limited disease (I to IIIA), 15 had laparotomy and adequate treatment. Thirteen did not have a laparotomy and 7 were treated with involved-field irradiation. The 5-year survival rate in the laparotomy-staged and adequately treated group was 86%, but in the clinically staged group, only 35% (p = 0.006).

Age Factors↗

PubMed1984

Philosophy and quality control. Workload recording--why your laboratory should be in the data bank.

The CAP Workload Recording (WLR) Method is the only widely accepted and validated method for recording laboratory workload. Here, the author details how unit values are assigned, how and by whom the data are used, how to quality control the data, and why an adequate comparative data base, such as the CAP Computer Assisted WLR Program, is so important to laboratories.

Hospital Departments↗

PubMed1984

Clinical relevance of immunologic phenotype in diffuse large cell lymphoma.

The immunologic phenotypes of 78 diffuse large cell lymphomas were determined by an immunoperoxidase technique using a panel of monoclonal antibodies. The phenotypes were correlated with clinical and morphological parameters by univariate and multivariate analysis. Forty-one lymphomas (53%) expressed immunoglobulin (Ig+). Of the 37 cases that did not express immunoglobulin (Ig-), 9 expressed T cell antigens. Although the T cell phenotypes were antigenically heterogeneous, all cases represented mature T cell phenotypes. The majority of the remaining 28 cases expressed the B cell-associated antigen, B1. At 5 yr, actuarial survival for the Ig- patients was 63%, compared with 15% for the Ig+ patients. A significantly greater proportion of patients with Ig+ lymphomas were over the age of 65 at diagnosis. All of the 9 patients with marrow involvement were Ig+. Multiple factors were analyzed by the Cox regression procedure for their impact on survival, including antigenic profile, histologic grade, morphological classification, and numerous clinical parameters previously recognized to be of prognostic significance. In this analysis, stage, age greater than 65 yr, systemic symptoms, and marrow involvement had the greatest influence on survival. The survival difference between Ig- and Ig+ patients is explained by a higher proportion of Ig+ patients with these unfavorable prognostic factors. With our current immunologic methods, retrospective cell phenotyping analysis has not provided independent prognostic significance in diffuse large cell lymphoma. A prospective evaluation of similarly treated patients is needed to characterize the influence of phenotype fully and to determine its potential usefulness for therapy.

Adolescent↗

PubMed1984

The treatment of malignant histiocytosis.

Twenty-four consecutive cases of malignant histiocytosis (MH) treated at Stanford Medical Center between 1973 and 1983 have been reviewed. Most patients presented with systemic symptoms (91%) and advanced disease (stage IV, 80%). Multiple organ involvement was common. In six cases, pathologic tissue was further characterized by frozen section immune histochemistry, using a panel of monoclonal antibodies known to react with monocytes and macrophages, as well as a variety of hematopoietic cells. One case expressed a mature monocyte/macrophage phenotype; three cases were considered null cell or primitive lesions; and two cases were identified as probable T cell lymphomas. Seven patients underwent splenectomy. Two patients died prior to any treatment. Twenty-two patients were treated with CHOP (cyclophosphamide, Adriamycin, vincristine, prednisone) +/- bleomycin (B), +/- midcycle high-dose methotrexate (HD-MTX) with leucovorin rescue. Seven patients received prophylactic intrathecal MTX. Of 22 evaluable patients, there was a 68% complete response rate (CR), a 23% partial response rate (PR), and a 9% no response rate (NR). Median duration of CR was 30+ months; median duration of PR was 2.4 months. Median survival for patients attaining a CR has not been reached v 3 months for the PR and NR groups. For all 24 patients, median survival was 2 years, with a 5-year actuarial survival of 40%. Multivariate analysis revealed that a platelet count less than 150,000 (P Cox = .005) and the dose of drug delivered (P Cox = .057) were the most important prognostic factors. Prophylactic intrathecal MTX therapy and splenectomy did not influence survival. Although MH is an aggressive disease with a poor prognosis, it is potentially curable. Systematic and aggressive treatment should further improve the outcome.

Adolescent↗