Sequential Staging Research Articles

Multiple sequential staging of tasks: a new approach to parallel computations

Developing an efficient algorithm for solving a large linear system in a parallel computing environment is the major problem associated with the application of parallel processing to the numerical solution of large-scale engineering problems. This paper presents a new algorithm called Multiple Sequential Staging of Tasks (MSST) to speed up the solution of a large linear system. The technique of Sequential Staging of Tasks (SST) is a highly efficient approach to the parallel solution of a large linear system, but it is not suitable for middle- and large-scale parallel computers due to the idle periods of processors. The MSST technique partitions processors into groups and makes each group start its operation from a different row of a large linear system to remove the idle period. Therefore, MSST can be performed effectively on middle- and large-scale parallel computers and achieves a higher speed-up. Numerical results were obtained from computer experiments performed with a numerical solution method of the Poisson equation on a Dawning-1000 supercomputer (a distributed-memory MIMD architecture). The parallel speed-up is satisfactory. Copyright © 1999 John Wiley & Sons, Ltd.

Sequential staging systems for small-cell lung cancer

Sequential staging systems for small-cell lung cancer

Sequential Staging Systems for Small-Cell Lung Cancer

I thank Chauvin and colleagues for bringing their article entitled Pretreatment Staging Evaluation in Small-Cell Lung Carcinoma 1 to our attention. It is gratifying to see that a sequential staging system is effective in another population of patients with small-cell lung cancer. In their letter, Chauvin et al 2 addressed a number of similarities and differences between their study and the one published by us in the February issue of theArchives. 3 I would like to address these issues herein. The basic difference between the two retrospective studies is that our criteria of diagnosis of extensive disease involved identification of an actual organ site with metastatic disease either by means of imaging studies or by biopsy procedure. We used patient history and physical examination to identify two sites of disease, namely, the central nervous system and soft-tissue disease, to preferentially select the initial investigations to perform. Patients who were

Sequential staging systems for small-cell lung cancer

Sequential staging systems for small-cell lung cancer

Sequential Staging Systems for Small-Cell Lung Cancer

In a recent issue of theARCHIVES, Richardson et al 1 presented the cost-saving data of the use of an algorithm for staging small-cell lung cancer. 1 Among 20 160 permutations of a sequence of conventional staging procedures, they have selected the least expensive one, allowing to stop further detection of metastases as soon as an involved site has been identified. Using such a sequential method, only 60% of the 451 patients who were studied would need to undergo expensive staging procedures such as computed tomography and nucleide bone scans, as well as bone marrow aspiration and biopsy. The proposed decisional analysis allows a $1418 savings per patient, which is one third of the calculated cost of a complete staging. Using the same type of analysis with the same decision and judgment criterion, we have previously published similar results 2 in this disease. We have described a three-step staging system

Application of an Algorithm for Staging Small-cell Lung Cancer Can Save One Third of the Initial Evaluation Costs

Design of a cost-effective algorithm for staging disease in patients with small-cell lung cancer. An algorithm was constructed by analyzing all permutations of a sequence of procedures required to stage disease in patients with small-cell lung cancer. Procedural costs were determined, and the model was applied to the small-cell lung cancer patient population treated at the National Cancer Institute, Bethesda, Md, from 1973 to 1989. The final algorithm was derived from the permutation with the lowest cost per accurately staged patient. A single government institute, the National Cancer Institute. Four hundred fifty-one patients with previously untreated, consecutive histologically documented small-cell lung cancer entered into therapeutic protocols at the National Cancer Institute from April 1973 through July 1989. Data were obtained from small-cell lung cancer protocol databases and patients' medical records. The cost per patient of each sequence of staging procedures when applied to the patient population. The least expensive sequence of procedures saved $1418 per patient when compared with application of a standard set of staging procedures to all patients. The major factor in reducing costs was the concept of stopping the staging procedures after a site of distant metastatic disease had been identified. An algorithm consisting of a set of sequential staging procedures can accurately stage disease in patients with small-cell lung cancer and save more than one third of the costs of an inclusive standard set of staging procedures.

Concurrent computing by sequential staging of tasks

Described is a new approach to parallel formulation of scientific problems on shared-memory multiprocessors such as the IBM ES/3090 system. The class of problems considered is characterized by repetitive operations applied over the computational domain D. In each such operation, some fields of interest are extrapolated or advanced by an amount of Δτ. The integration variable τ may be time, distance, or iteration sequence number, depending on the problem under consideration. An extensively studied approach to parallel formulation of such computational problems is based on domain decomposition, which attempts to partition the domain of integration into many pieces, then construct the global solution from these local solutions. Thus, domain decomposition methods are confined to D alone at a single τ level. An inquiry into the possibilities of formulating parallel tasks in τ, or more significantly in the D × τ domain, opens up new horizons and untapped opportunities. The aim of this paper is to detail an approach to exploit this τ domain parallelism that will be referred to as sequential staging of tasks (SST). Concurrency is realized by means of ordering the tasks sequentially and executing them in a partially overlapped or pipelined manner. The SST approach can yield remarkable speedup for jobs requiring intensive paging I/O, even when a single processor is available for executing multiple tasks. Noteworthy features of the SST method are demonstrated and highlighted by using results obtained from computer experiments performed with a numerical solution method of the Poisson equation and migration of seismic reflection data.

Staging and therapy of orbital lymphomas.

Ten patients with non-Hodgkin's lymphoma primarily affecting the orbital region were evaluated at Michael Reese Hospital and Medical Center, Chicago, between 1976 and 1983. Diagnoses were based on the histopathologic classification systems of the Working Formulation of the Non-Hodgkin's Lymphomas and Rappoport. Sequential staging procedures performed at the time of diagnosis included liver-spleen scans, Technecium-99 bone scans, gallium 67 scans, computerized axial tomograms of the orbit and abdomen, bone marrow examination and cerebral spinal fluid analyses. Adverse prognostic factors included the following: orbital bone erosions, Stage IV disease, and large cell or mixed cell, diffuse histologic features. The type of histopathologic findings combined with the results of sequential staging procedures is useful in identifying those patients who would benefit most from systemic chemotherapy.

A Universal Controller for Parallel Pumps with Variable-Frequency Drives

There is an established trend to install variable-frequency drives in pumping applications. The object is to obtain continuously variable flow with high efficiency, while retaining the ability to bypass the drive via direct line operation of the ac induction motor. The system specifications often include parallel banks of pumps; with elaborate requirements for sequential staging in response to demand, alternation to equalize wear, and automatic accommodation of component failures. A universal controller is described that has been developed for such applications. Operating experience is summarized on more than 50 installations over the past three years.

Sequential Staging in Bronchogenic Carcinoma

The results of staging in 115 patients with primary lung carcinoma are presented. All patients underwent a sequential process of evaluation including the following: initial staging (IS), consisting of physical examination, chest roentgenograms, and standard clinical laboratory tests; clinical staging (CS), consisting of liver-spleen scan, bone scan, computed tomography (CT) scan of the brain, and a total-body gallium citrate scan; and final staging (FS), consisting of histological verification (biopsy) of lymph node, or in most cases, sites of distant organ metastases suspected by IS and/or CS findings. Twentyone (18 percent) patients were IS III_MI; however, following clinical staging, the number of patients with metastatic disease was increased to 50 (43 percent). The value and significance of IS, besides being the first step in the sequential staging procedure, is its high accuracy for determining stage III_MI* Clinical staging significantly changed the IS result in patients with other than III_MI disease; 39 (25 percent) patients advanced to CS III_MI and 9 (8 percent) to both CS II or III_M0. No patient had less extensive disease than suspected from IS. The gallium citrate ⁶⁷Ga scan was the most rewarding CS test showing uptake in 96 percent of the primary tumors. Following CS procedures, three patients were advanced by FS to III_MI, and five had less disease than suspected and were switched from CS II to FS I. This study shows that clinical staging significantly improves the accuracy of determining the extent of disease over initial staging in those patients who do not have obvious clinical evidence of metastases. Final staging results compare satisfactorily with clinical staging results. Careful clinical staging allows for accurate identification of the extent of disease which has both prognostic and therapeutic consequences.

Lung Cancer: A Combined Modality Approach to Staging and Therapy

This review paper emphasizes the importance of the histological diagnosis of the lung tumor by carefully outlining the TNM staging system for carcinoma of the lung, formulated by the task force on carcinoma of the lung of the American Joint Committee for Staging and End Result Reporting. The use of Gallium 67 in the sequential staging of the disease is discussed. The treatments of this disease that have been found effective include surgery, radiotherapy, combination chemotherapy and immunotherapy. (KRM)

Non-Hodgkin's lymphoma, poorly differentiated lymphocytic and mixed cell types: results of sequential staging procedures, response to therapy, and survival of 100 patients.

The results of sequential staging procedures including laparotomy, radiotherapy, and combination chemotherapy are reported for 100 patients with poorly differentiated lymphocytic (PDL) and mixed cell (MC) non-Hodgkin's lymphoma (NHL). Twelve patients were found to have localized disease, pathologic stage (PS) I or II; 88 patients had PS III or IV disease. Bone marrow biopsy showed a high incidence of involvement and advanced 34% of the patients from CS I, II, and III to PS IV. Staging laparotomy has a very limited role in the evaluation of these patients. All of 12 patients with PS I and II NHL were treated with radiotherapy; at 5 years, they had 100% survival, 80% being disease-free. Fifteen patients with PS III disease were treated with total nodal radiotherapy (TNRT) alone and had a median disease-free survival of 41 months. The remaining patients with PS III and IV disease were treated with chemotherapy consisting of vincristine and prednisone (V & P); cyclophosphamide, vincristine (Oncovin®), procarbazine, and prednisorte (COPP); cyclophosphamide, vincristine (Oncovin®), adriamycin, and prednisone (COPA); or “palliative therapy”, consisting of chlorambucil and prednisone. Two-year and 4-year survivals for patients with diffuse lymphoma were 93% and 60%, respectively; for patients with +2 nodular lymphoma, 80% and 30%; for patients with nodular lymphomas, 76–93% and 50%, respectively. Treatment with COPP showed no advantage over V and P, “palliative therapy,” or TNRT for patients with +2 nodular and nodular disease. The likelihood of cure appears most promising for patients in complete remission (CR) with diffuse lymphoma; patients in CR with nodular lymphoma show a high rate of relapse over 5 years of observation. We conclude that staging laparotomy in PDL and MC NHL is of limited value, and that the role of aggressive chemotherapy for patients with +2 nodular and nodular lymphoma needs to be redefined.