Dynamic causal modelling

In this paper we present an approach to the identification of nonlinear input-state-output systems. By using a bilinear approximation to the dynamics of interactions among states, the parameters of the implicit causal model reduce to three sets. These comprise (1) parameters that mediate the influence of extrinsic inputs on the states, (2) parameters that mediate intrinsic coupling among the states, and (3) [bilinear] parameters that allow the inputs to modulate that coupling. Identification proceeds in a Bayesian framework given known, deterministic inputs and the observed responses of the system. We developed this approach for the analysis of effective connectivity using experimentally designed inputs and fMRI responses. In this context, the coupling parameters correspond to effective connectivity and the bilinear parameters reflect the changes in connectivity induced by inputs. The ensuing framework allows one to characterise fMRI experiments, conceptually, as an experimental manipulation of integration among brain regions (by contextual or trial-free inputs, like time or attentional set) that is revealed using evoked responses (to perturbations or trial-bound inputs, like stimuli). As with previous analyses of effective connectivity, the focus is on experimentally induced changes in coupling (cf., psychophysiologic interactions). However, unlike previous approaches in neuroimaging, the causal model ascribes responses to designed deterministic inputs, as opposed to treating inputs as unknown and stochastic.

Monkeypox Virus Infection in Humans across 16 Countries - April-June 2022

BACKGROUND

Before April 2022, monkeypox virus infection in humans was seldom reported outside African regions where it is endemic. Currently, cases are occurring worldwide. Transmission, risk factors, clinical presentation, and outcomes of infection are poorly defined.

METHODS

We formed an international collaborative group of clinicians who contributed to an international case series to describe the presentation, clinical course, and outcomes of polymerase-chain-reaction-confirmed monkeypox virus infections.

RESULTS

We report 528 infections diagnosed between April 27 and June 24, 2022, at 43 sites in 16 countries. Overall, 98% of the persons with infection were gay or bisexual men, 75% were White, and 41% had human immunodeficiency virus infection; the median age was 38 years. Transmission was suspected to have occurred through sexual activity in 95% of the persons with infection. In this case series, 95% of the persons presented with a rash (with 64% having ≤10 lesions), 73% had anogenital lesions, and 41% had mucosal lesions (with 54 having a single genital lesion). Common systemic features preceding the rash included fever (62%), lethargy (41%), myalgia (31%), and headache (27%); lymphadenopathy was also common (reported in 56%). Concomitant sexually transmitted infections were reported in 109 of 377 persons (29%) who were tested. Among the 23 persons with a clear exposure history, the median incubation period was 7 days (range, 3 to 20). Monkeypox virus DNA was detected in 29 of the 32 persons in whom seminal fluid was analyzed. Antiviral treatment was given to 5% of the persons overall, and 70 (13%) were hospitalized; the reasons for hospitalization were pain management, mostly for severe anorectal pain (21 persons); soft-tissue superinfection (18); pharyngitis limiting oral intake (5); eye lesions (2); acute kidney injury (2); myocarditis (2); and infection-control purposes (13). No deaths were reported.

CONCLUSIONS

In this case series, monkeypox manifested with a variety of dermatologic and systemic clinical findings. The simultaneous identification of cases outside areas where monkeypox has traditionally been endemic highlights the need for rapid identification and diagnosis of cases to contain further community spread.

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

Long-term results of a prospective randomized trial of adjuvant brachytherapy in soft tissue sarcoma

PURPOSE

This trial was performed to evaluate the impact of adjuvant brachytherapy on local and systemic recurrence rates in patients with soft tissue sarcoma.

PATIENTS AND METHODS

In a single-institution prospective randomized trial, 164 patients were randomized intraoperatively to receive either adjuvant brachytherapy (BRT) or no further therapy (no BRT) after complete resection of soft tissue sarcomas of the extremity or superficial trunk. The adjuvant radiation was administered by iridium-192 implant, which delivered 42 to 45 Gy over 4 to 6 days. The two study groups had comparable distributions of patient and tumor factors, including age, sex, tumor site, tumor size, and histologic type and grade.

RESULTS

With a median follow-up time of 76 months, the 5-year actuarial local control rates were 82% and 69% in the BRT and no BRT groups (P = .04), respectively. Patients with high-grade lesions had local control rates of 89% (BRT) and 66% (no BRT) (P = .0025). BRT had no impact on local control in patients with low-grade lesions (P = .49). The 5-year freedom-from-distant-recurrence rates were 83% and 76% in the BRT and no BRT groups (P = .60), respectively. Analysis by histologic grade did not demonstrate an impact of BRT on the development of distant metastasis, despite the improvement in local control noted in patients with high-grade lesions. The 5-year disease-specific survival rates for the BRT and no BRT groups were 84% and 81% (P = .65), respectively, with no impact of BRT regardless of tumor grade.

CONCLUSION

Adjuvant brachytherapy improves local control after complete resection of soft tissue sarcomas. This improvement in local control is limited to patients with high-grade histopathology. The reduction in local recurrence in patients with high-grade lesions is not associated with a significant reduction in distant metastasis or improvement in disease-specific survival.

Continuous intravenous heparin compared with intermittent subcutaneous heparin in the initial treatment of proximal-vein thrombosis

We performed a randomized double-blind trial comparing continuous intravenous heparin with intermittent subcutaneous heparin in the initial treatment of 115 patients with acute proximal deep-vein thrombosis. Intermittent subcutaneous heparin as administered in this trial was inferior to continuous intravenous heparin in preventing recurrent venous thromboembolism. The subcutaneous heparin regimen induced an initial anticoagulant response below the target therapeutic range in the majority of patients and resulted in a high frequency of recurrent venous thromboembolism (11 of 57 patients, 19.3 percent), which was virtually confined to patients with a subtherapeutic anticoagulant response. In contrast, continuous intravenous heparin induced a therapeutic anticoagulant response in the majority of patients and a low frequency of recurrent events (3 of 58 patients, 5.2 percent; P = 0.024); the recurrences were limited to patients with an initial subtherapeutic anticoagulant response. The results of this trial establish the efficacy of intravenous heparin in the treatment of proximal venous thrombosis and suggest a relation between the effectiveness of heparin and the levels of anticoagulation achieved; such a relation could explain the observed failure of the subcutaneous regimen.

Use of decision analysis in planning a management strategy for the stage N0 neck

OBJECTIVE

There are three major strategies in the treatment of patients with a stage N0 neck with squamous cell cancer of the head and neck: elective neck dissection, elective neck irradiation, and observation. Each has appropriate salvage strategies in the event of local recurrence. We used decision analysis to determine the optimal strategy for neck treatment as a function of the probability of occult cervical metastasis.

DATA SOURCES

We used the bibliographies of current articles and books to access clinical studies of patients with stage N0 neck cancer.

STUDY SELECTION

Studies that included large numbers of patients and contained a minimum 2-year follow-up, with results analyzed in terms of outcome as a function of stage of neck disease, were included.

DATA EXTRACTION

Specific data points were extracted from the studies independently by multiple observers, and mean values were used in the decision analysis.

DATA SYNTHESIS

A decision tree was constructed with use of a computer model to compare the three management strategies. Probabilities of each of the possible events depicted in the trees were inserted into the tree structure. These probabilities were gleaned from the literature as described above. A sensitivity analysis was performed to determine the optimal threshold for treatment of the neck.

CONCLUSION

A patient with primary squamous cell carcinoma of the head and neck and stage N0 neck status should be observed if the probability of occult cervical metastasis is less than 20%. If the probability is greater than 20%, treatment of the neck is warranted. The treatment plan should ideally involve a single modality of therapy; both neck dissection and radiation therapy are quite efficacious in the clinical context, and the decision of which one to employ should be driven by the treatment of the primary lesion. Decision analysis is useful in complex clinical situations.

A phase II trial of surgical resection and adjuvant high-dose hemithoracic radiation for malignant pleural mesothelioma

BACKGROUND

Surgical resection of malignant pleural mesothelioma is reported to have up to an 80% rate of local recurrence. We performed a phase II trial of high-dose hemithoracic radiation after complete resection to determine feasibility and to estimate rates of local recurrence and survival.

METHODS

Patients were eligible if they had a resectable tumor, as determined by computed tomographic scanning, and adequate cardiopulmonary function for extrapleural pneumonectomy or pleurectomy/decortication. After complete resection, patients received hemithoracic radiation (54 Gy) and then were followed up with serial computed tomographic scanning.

RESULTS

From 1995 to 1998, 88 patients (73 men and 15 women; median age, 62.5 years) were entered into the study. The operations performed included 62 extrapleural pneumonectomies (70%) and 5 pleurectomies/decortications; procedures for exploration only were performed in 21 patients. Seven (7.9%) patients died postoperatively. Adjuvant radiation administered to 57 patients (54 undergoing extrapleural pneumonectomy and 3 undergoing pleurectomy/decortication) at a median dose of 54 Gy was well tolerated (grade 0-2 fatigue, esophagitis), except for one late esophageal fistula. The median survival was 33.8 months for stage I and II tumors but only 10 months for stage III and IV tumors (P =.04). For the patients undergoing extrapleural pneumonectomy, the sites of recurrence were locoregional in 2, locoregional and distant in 5, and distant only in 30.

CONCLUSION

Hemithoracic radiation after complete surgical resection at a dose not previously reported is feasible. This approach dramatically reduces local recurrence and is associated with prolonged survival for early-stage tumors. Stage III disease has a high risk of early distant relapse and should be considered for trials of systemic therapy added to this regimen of resection and radiation.

Tumor control and morbidity following transperineal iodine 125 implantation for stage T1/T2 prostatic carcinoma

PURPOSE

To quantify disease progression and morbidity following computer tomography (CT)-based transperineal iodine 125 prostate implantation.

METHODS

Ninety-two patients with clinical stage T1 or T2, Gleason score 2 to 7/10, prostatic carcinoma had outpatient, CT-based transperineal 125I prostate implantation and were monitored for 1 to 7 years (median, 3). The prescribed minimum radiation dose was 140 to 160 Gy. Lymph node dissection and postimplantation prostatic biopsies were not routinely performed.

RESULTS

In 46% of patients, radiation-related urinary symptoms were substantial enough at 1 month following implantation to require medication. Radiation-related urinary symptoms gradually resolved. Two years after implantation, 14% of patients had persistent urinary symptoms of Radiation Therapy Oncology Group (RTOG) > or = grade 2. Eight percent of patients underwent a transurethral resection of the prostate (TURP) within 2 years of implantation. Five patients developed radiation-induced rectal ulcerations. Of 56 patients who were sexually potent preimplantation, 86% retained potency at 3 years. Twenty-five patients had biochemical disease progression. The overall actuarial freedom from biochemical failure rate at 4 years following implantation was 63%. In Cox proportional hazards multivariate analysis, the strongest predictor of failure was prostate-specific antigen (PSA) level less than or greater than 10 ng/mL (P = .005), followed by Gleason score (2 to 4 v 5 to 7, P = .08) and stage (T1 v T2, P = .09).

CONCLUSION

The 5-year biochemical freedom-from-progression rates following transperineal 125I implantation are comparable with those achieved with prostatectomy. The morbidity has decreased with increased physician experience.

Comparison of 5-mg and 10-mg loading doses in initiation of warfarin therapy

BACKGROUND

Loading doses of warfarin that are larger than those used for maintenance therapy are widely used in clinical practice, but they have never been prospectively evaluated.

OBJECTIVE

To compare the effect of 5- and 10-mg loading doses of warfarin on laboratory markers of warfarin's anticoagulant effect.

DESIGN

Randomized clinical trial.

SETTING

Tertiary care teaching hospital.

PATIENTS

49 patients seen over a 5-month period with a target international normalized ratio (INR) of 2.0 to 3.0.

INTERVENTION

Patients were randomly assigned to receive an initial dose of 5 or 10 mg of warfarin. Subsequent doses of warfarin were administered on the basis of dosing nomograms.

MEASUREMENTS

INRs and levels of factors II, VII, IX, and X and protein C were measured daily for 5 days.

RESULTS

11 of 25 patients in the 10-mg group (44% [95% CI, 34% to 54%]) and 2 of 24 patients in the 5-mg group (8% [CI, 3% to 14%]) had INRs greater than 2.0 at 36 hours (P = 0.005), at which time the factor VII levels were 27% (CI, 18% to 36%) in the 10-mg group and 54% (CI, 43% to 65%) in the 5-mg group (P < 0.001). In contrast, factor II levels were 74% (CI, 67% to 81%) in the 10-mg group and 82% (CI, 73% to 93%) in the 5-mg group (P > 0.2). At 60 hours, 9 of 25 patients in the 10-mg group (36% [CI, 17% to 54%]) and no patients in the 5-mg group had INRs greater than 3.0. At 84 hours, 15 of 24 patients in the 10-mg group (63% [CI, 43% to 81%]) and 19 of 24 patients in the 5-mg group (79% [CI, 62% to 95%]) had INRs between 2.0 and 3.0. Four patients in the 10-mg group and 1 patient in the 5-mg group received vitamin K for excessive prolongation of the INR.

CONCLUSIONS

A 5-mg loading dose of warfarin produces less excess anticoagulation than does a 10-mg loading dose; the smaller dose also avoids the development of a potential hypercoagulable state caused by precipitous decreases in levels of protein C during the first 36 hours of warfarin therapy.

Dosimetry guidelines to minimize urethral and rectal morbidity following transperineal I-125 prostate brachytherapy

PURPOSE

To establish dosimetry guidelines to minimize urethral and rectal morbidity following permanent I-125 prostatic brachytherapy.

METHODS AND MATERIALS

Dosimetric parameters were correlated with long-term morbidity for 65 patients following transperineal I-125 implantation for Stage T1/T2 prostatic carcinoma. The prescribed minimum prostatic dose was 150 Gy. The median total activity used was 48 mCi (range: 32-77 mCi). Patients were followed for 1-5 years (median follow-up: 2 years). Postimplant computerized tomography (CT)-based dosimetry was performed for 45 patients. Morbidity was evaluated using a modification of the RTOG grading system, with a scale of grade 0-5.

RESULTS

The incidence of grades 2 and 3 urinary morbidity was associated with the maximum central urethral dose (p = 0.03), and with the length of urethra that received greater than 400 Gy (p = 0.07). Patients with larger prostates had more long-term urinary morbidity (p = 0.06). Rectal bleeding (RTOG grade 1) or ulceration (RTOG grade 2) was associated with irradiation of the rectal wall to doses in excess of 100 Gy (p = 0.02). There was no relationship between the matched peripheral dose (MPD), mCi/source or total mCi implanted and long-term morbidity.

CONCLUSIONS

Postimplant, CT-based dosimetry can predict which patients are at higher risk of radiation-related morbidity. More simplistic parameters including the MPD, total activity implanted, or mCi/source, had no relationship with morbidity. To decrease the risk of long-term morbidity, an effort should be made to keep the central urethral dose below 400 Gy, and the rectal surface dose below 100 Gy.

The indications for elective treatment of the neck in cancer of the major salivary glands

To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group.

Malignant tumors of major salivary gland origin. A matched-pair analysis of the role of combined surgery and postoperative radiotherapy

Between 1966 and 1982, 46 patients with previously untreated malignant tumors of major salivary gland origin received combined surgery and postoperative radiotherapy. They were compared with 46 patients treated with surgery only between 1939 and 1965, who were matched according to prognostic criteria. Radiation doses ranged from 4000 to 7740 cGy (median, 5664 cGy). The 5-year determinate survival rates for patients given combined therapy with stage I and II disease vs patients given surgery only was 81.9% vs 95.8%, while for stages III and IV it was 51.2% vs 9.5%, respectively. Local control for stage III and IV disease in patients given combined therapy vs patients given surgery only at 5 years was 51.3% vs 16.8%. For patients with nodal metastases, 5-year determinate survival for the combined-therapy group vs the surgery-only group was 48.9% vs 18.7%, and the corresponding local-regional control was 69.1% vs 40.2%. The results of this analysis suggest that postoperative radiotherapy significantly improves outcome for patients with stage III and IV disease and for patients with lymph node metastases.

Multivariate autoregressive modeling of fMRI time series

We propose the use of multivariate autoregressive (MAR) models of functional magnetic resonance imaging time series to make inferences about functional integration within the human brain. The method is demonstrated with synthetic and real data showing how such models are able to characterize interregional dependence. We extend linear MAR models to accommodate nonlinear interactions to model top-down modulatory processes with bilinear terms. MAR models are time series models and thereby model temporal order within measured brain activity. A further benefit of the MAR approach is that connectivity maps may contain loops, yet exact inference can proceed within a linear framework. Model order selection and parameter estimation are implemented by using Bayesian methods.

Prediction of MHC class II-binding peptides using an evolutionary algorithm and artificial neural network

MOTIVATION

Prediction methods for identifying binding peptides could minimize the number of peptides required to be synthesized and assayed, and thereby facilitate the identification of potential T-cell epitopes. We developed a bioinformatic method for the prediction of peptide binding to MHC class II molecules.

RESULTS

Experimental binding data and expert knowledge of anchor positions and binding motifs were combined with an evolutionary algorithm (EA) and an artificial neural network (ANN): binding data extraction --> peptide alignment --> ANN training and classification . This method, termed PERUN, was implemented for the prediction of peptides that bind to HLA-DR4(B1*0401). The respective positive predictive values of PERUN predictions of high-, moderate-, low- and zero-affinity binders were assessed as 0.8, 0.7, 0.5 and 0.8 by cross-validation, and 1.0, 0.8, 0.3 and 0.7 by experimental binding. This illustrates the synergy between experimentation and computer modeling, and its application to the identification of potential immunotherapeutic peptides.

AVAILABILITY

Software and data are available from the authors upon request.

CONTACT

vladimir@wehi.edu. au

Clinical outcomes of melanoma brain metastases treated with stereotactic radiation and anti-PD-1 therapy

BACKGROUND

The anti-programmed death-1 (anti-PD-1) therapy nivolumab has significant clinical activity in patients with metastatic melanoma. However, little is known about the safety and outcomes in patients receiving anti-PD-1 therapy and stereotactic radiation for the treatment of brain metastases (BMs).

PATIENTS AND METHODS

Data were analyzed retrospectively from two prospective nivolumab protocols enrolling 160 patients with advanced resected and unresectable melanoma at a single institution. Patients were included if BMs were diagnosed and treated with stereotactic radiation within 6 months of receiving nivolumab. The primary end point of this study was neurotoxicity; secondary end points included BM control and survival.

RESULTS

Twenty-six patients with a total of 73 BMs treated over 30 sessions were identified. Radiation was administered before, during and after nivolumab in 33 lesions (45%), 5 lesions (7%), and 35 lesions (48%), respectively. All BMs were treated with stereotactic radiosurgery (SRS) in a single session except 12 BMs treated with fractionated stereotactic radiation therapy, nine of which were in the postoperative setting. One patient experienced grade 2 headaches following SRS with symptomatic relief with steroid treatment. No other treatment-related neurologic toxicities or scalp reactions were reported. Eight (11%) local BM failures with a ≥20% increase in volume were noted. Of these lesions, hemorrhage was noted in 4, and edema was noted in 7. Kaplan-Meier estimates for local BM control following radiation at 6 and 12 months were 91% and 85%, respectively. Median overall survival (OS) from the date of stereotactic radiation and nivolumab initiation was 11.8 and 12.0 months, respectively, in patients receiving nivolumab for unresected disease (median OS was not reached in patients treated in the resected setting).

CONCLUSIONS

In our series, stereotactic radiation to melanoma BMs is well tolerated in patients who received nivolumab. BM control and OS appear prolonged compared with standard current treatment. Prospective evaluation is warranted.

Food items and food groups as risk factors in a case-control study of diet and colo-rectal cancer

The contributions of food items and food groups as risk factors in a previously reported case-control study of diet and colo-rectal cancer have been analyzed. The study included 348 patients with colon cancer, 194 with rectal cancer, 542 neighbourhood controls individually matched to the cases on the basis of age and sex and a second control series of 535 surgical hospital controls frequency matched to the cases. For colon cancer, as in the previous analysis, the major risk factor was saturated fat, individual food items or groups failing to make a significant contribution to the risk. In particular there was no protective effect of dietary fibre and, for cruciferous vegetables, only a minor protective effect in females. No individual cruciferous vegetable made an important contribution to this effect. For rectal cancer, on the other hand, a significant effect of saturated fat, independent of other food items or groups, was only found for females in the highest consumption category. For males, consumption of eggs, beef and veal significantly increased risk but not consumption of pork, while for females, there was a non-significant increase in risk with consumption of eggs, no increased risk with consumption of beef or veal and a significantly increased risk with consumption of pork. There was no protective effect of dietary fibre or of cruciferous vegetables for rectal cancer, but in females, there was a significantly increased risk for consumption of beer, though this was somewhat reduced when controlled for consumption of saturated fat. There was no indication of an effect of alcohol in either sex or of beer in males. Thus, these results confirm the previous report in showing a significant effect of saturated fat in increasing risk of colon cancer but suggest a contribution of meats to risk of rectal cancer.

Detailed quality of life assessment in patients treated with primary radiotherapy for squamous cell cancer of the base of the tongue

BACKGROUND

This study was conducted to evaluate quality of life in patients treated with primary radiotherapy (RT) for cancer of the base of tongue.

METHODS

From 1981 to 1990, 36 patients with primary squamous cell cancer of the base of tongue were managed with primary radiotherapy. Ages ranged from 35 to 71 years (median, 58 years), T Stage was: T1, n = 11; T2, n = 14; T3, n = 10; T4, n = 1. Thirty-one patients (86%) had palpable cervical lymph node metastases at initial examination (N1, n = 16; N2, n = 11; N3, n = 4). Patients received external beam RT to their primary site and necks, followed by a brachytherapy boost to the tongue. Those with neck nodes also had a neck dissection. The median follow-up is 5 years (minimum, 3 years). Actuarial 5-year local control was 85%; regional control was 96%; distant metastases-free survival was 87.5%; and overall survival, 85%. Twenty-nine of the 30 long-term survivors completed (1) Memorial Symptom Assessment Scale (MSAS), (2) Functional Assessment of Cancer Therapy (FACT), (3) Performance Status Scale for Head and Neck Cancer (PSS), and (4) a sociodemographic and economic questionnaire. At the time of cancer diagnosis, 62% were employed full-time, and 21% were employed part-time; 83% were earning > $20,000/year, and 59% were earning > $60,000/year.

RESULTS

At follow-up, annual incomes were similar to those at initial examination. Of those who had been working full-time, 72% were still in full-time work, and of those who had been working part-time, 83% were still in part-time work. Average PSS scores were 90 for eating in public, 96 for understandability of speech, and 68 for normalcy of diet. On the MSAS, the following symptoms had prevalence: > 30% xerostomia, difficulty swallowing, decreased energy, pain, worrying, insomnia, cough, drowsy, change in taste, and irritability. Scores on the FACT exceeded published values collected for a mixed cancer population.

CONCLUSIONS

The overwhelming majority of patients achieved excellent functional status and quality of life and could maintain their prediagnosis earning potential and employment status after primary radiation for advanced base of tongue cancer.

Promising survival with three-dimensional conformal radiation therapy for non-small cell lung cancer

PURPOSE

Local failure is a major obstacle to the cure of locally advanced non small-cell lung cancer. Three-dimensional conformal radiation therapy (3-DCRT) selects optimal treatment parameters to increase dose to tumor and reduce normal tissue dose, potentially representing an enhancement of the therapeutic ratio of radiation therapy for lung cancer. We performed this analysis of 45 non-small cell lung cancer patients treated with 3-DCRT alone, to evaluate the ability of computer derived lung dose volume histograms to predict serious pulmonary toxicity, to assess the feasibility of this approach, and to examine the resulting survival.

METHODS

There were 28 males (62%) and 17 females (38%). The median age was 65 (range: 38-82). Tumor stage was Stage I/II in 13%, IIIa in 42%, and IIIb in 44%. The histology was squamous in 44%, adenocarcinoma in 36%, and other non-small cell histologies in the others. Only 47% of patients. had combined favorable prognostic factors (i.e. KPS < or = 80, and < or = 5% wt. loss). The median dose of radiation to gross disease was 70.2 Gy (range: 52.2-72 Gy) delivered in fractions of 1.8 Gy, 5 days per week.

RESULTS

Seven patients did not complete 3-DCRT due to disease progression outside the port. Follow-up data are mature: the median follow up of the 6 survivors is 43.5 months (35-59). Thoracic progression occurred in 46%. Median survival (all 45 patients.) is 15.7 months and survival is 32% at 2 years and 12% at 59 months. Pulmonary toxicity > or = grade 3 occurred in 9% of patients. Dose volume histograms were available in 31 patients and showed a correlation between risk of pulmonary toxicity and indices of dose to lung parenchyma. Grade 3 or higher pulmonary toxicity occurred in 38% (3/8) of patients with > 30% of lung volume receiving > or = 25 Gy, versus 4% (1/23) of patients with < or = 30% lung receiving > or = 25 Gy (P = 0.04). Grade 3 or higher pulmonary toxicity occurred in 29% (4/14) of patients with a predicted pulmonary normal tissue complication probability of 12% or higher versus 0% (0/17) in patients with a predicted probability of less than 12% (P = 0.03).

CONCLUSIONS

Despite adverse prognostic criteria median survival is encouraging and may be higher than some combined modality approaches. Dose volume histogram parameters may be useful to determine the maximum dose for individual patients and thereby permit avoidance of toxicity.

The role of multimodality therapy in soft-tissue sarcoma

Soft-tissue sarcomas are uncommon malignancies. The development during a period of 8 years, in one institution, of a prospective data base incorporating more than 1600 patients with these tumors is described. The most common sites for occurrence are the extremities, but they can occur in any of the soft tissues of the body. Liposarcoma and leiomyosarcoma are the most common histopathologic conditions identified. Prognostic factors for both recurrence and survival include site, histopathology, size, grade, and adequacy of resection. A prospective randomized trial of the use of adjuvant radiation by the brachytherapy technique in extremity lesions has shown a decrease in local recurrence, but no impact on survival. Eligible patients not randomized to the trial show no difference in local recurrence or survival, regardless of whether they received adjuvant radiation.

Active bacterial core surveillance of the emerging infections program network

Active Bacterial Core surveillance (ABCs) is a collaboration between the Centers for Disease Control and Prevention and several state health departments and universities participating in the Emerging Infections Program Network. ABCs conducts population-based active surveillance, collects isolates, and performs studies of invasive disease caused by Streptococcus pneumoniae, group A and group B Streptococcus, Neisseria meningitidis, and Haemophilus influenzae for a population of 17 to 30 million. These pathogens caused an estimated 97,000 invasive cases, resulting in 10,000 deaths in the United States in 1998. Incidence rates of these pathogens are described. During 1998, 25% of invasive pneumococcal infections in ABCs areas were not susceptible to penicillin, and 13.3% were not susceptible to three classes of antibiotics. In 1998, early-onset group B streptococcal disease had declined by 65% over the previous 6 years. More information on ABCs is available at www.cdc.gov/ncidod/dbmd/abcs. ABCs specimens will soon be available to researchers through an archive.

Carcinoma of major salivary glands. Recent trends

We have reviewed a 44-year experience with previously untreated carcinomas arising in major salivary glands to compare 319 patients treated before 1966 with 155 who received therapy between 1966 and 1982. Actuarial analysis indicates that five- and ten-year survival of our more recently treated patients was 80% and 65%, compared with 60% and 50% in patients treated before 1966. Explanation for this includes the higher proportion of patients with less aggressive histologic subtypes seen in recent years, as well as the fact that many of our patients treated before 1966 had surgical procedures considered inadequate by current standards. We also believe that adjunctive radiation oncology enhanced survival, but it could not be proved in this retrospective study. Multivariate analysis confirms that the clinical stage was the most important prognostic variable.

Long-term results of a prospective randomized trial of adjuvant brachytherapy in the management of completely resected soft tissue sarcomas of the extremity and superficial trunk

PURPOSE

A prospective randomized trial evaluating adjuvant brachytherapy for soft tissue sarcomas was conducted between July 1982 and July 1987.

METHODS AND MATERIALS

One hundred twenty-six patients with soft tissue sarcoma of the extremity or superficial trunk (STS) underwent grossly complete resection with limb-sparing surgery. Intra-operatively, patients were randomized to receive either adjuvant brachytherapy (BRT) or no further therapy (no BRT). BRT consisted of an Iridium-192 implant which delivered 4200-4500 cGy over 4-6 days. Total hospital stay for combined surgery and BRT was 10-14 days. Patients in each group were well matched with respect to age, sex, site, tumor size, depth, histologic type, and grade. Median follow-up is 66.5 months for all living patients.

RESULTS

At 5 years, local control was 82% in the BRT group vs. 67% in the no BRT group (p = .049). When analyzed by histologic grade, high grade tumors had local control of 90% with BRT vs. 65% with no BRT (p = .013). There was no difference in local control in the low grade patients in either arm. At 5 years, the proportion free of distant metastases was approximately 76% in both arms, with no difference between BRT and no BRT. When analyzed by grade, high grade patients had a similar proportion free of distant metastasis in the BRT vs. no BRT arms despite improved local control in those receiving BRT. Similarly, the disease-specific survival for all patients at 5 years was 81% for BRT vs. 80% for no BRT (p = NS). When analyzed by grade, and treatment (BRT vs. no BRT), 5-year disease-specific survival for high grade was the same in both groups.

CONCLUSIONS

Adjuvant BRT significantly improves local control in completely resected STS. This improvement is confined to patients with high grade histology. BRT provides excellent local control in this group, and significantly shortens the treatment time when compared to adjuvant external beam radiation. However, the improved local control does not translate into either decreased distant metastasis or increased disease-specific survival.

Consensus guidelines from The American Society of Peritoneal Surface Malignancies on standardizing the delivery of hyperthermic intraperitoneal chemotherapy (HIPEC) in colorectal cancer patients in the United States

BACKGROUND

The American Society of Peritoneal Surface Malignancies (ASPSM) is a consortium of cancer centers performing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). This is a position paper from the ASPSM on the standardization of the delivery of HIPEC.

METHODS

A survey was conducted of all cancer centers performing HIPEC in the United States. We attempted to obtain consensus by the modified method of Delphi on seven key HIPEC parameters: (1) method, (2) inflow temperature, (3) perfusate volume, (4) drug, (5) dosage, (6) timing of drug delivery, and (7) total perfusion time. Statistical analysis was performed using nonparametric tests.

RESULTS

Response rates for ASPSM members (n = 45) and non-ASPSM members (n = 24) were 89 and 33 %, respectively. Of the responders from ASPSM members, 95 % agreed with implementing the proposal. Majority of the surgical oncologists favored the closed method of delivery with a standardized dual dose of mitomycin for a 90-min chemoperfusion for patients undergoing cytoreductive surgery for peritoneal carcinomatosis of colorectal origin.

CONCLUSIONS

This recommendation on a standardized delivery of HIPEC in patients with colorectal cancer represents an important first step in enhancing research in this field. Studies directed at maximizing the efficacy of each of the seven key elements will need to follow.