Oncologic Outcomes of Conventionally Fractionated, Hypofractionated, and Stereotactic Body Spot-Scanned Proton Radiation Therapy for Prostate Cancer: The Mayo Clinic Experience

PURPOSE/OBJECTIVE(S)

Spot/pencil beam scanned proton therapy is a relatively new technology with fundamental differences from double scattered or IMRT. We aimed to report the long-term oncologic outcomes of a contemporary prospective series of patients treated with spot-scanned proton therapy (SSPT).

MATERIALS/METHODS

An IRB-approved prospective registry identified patients with prostate cancer treated with proton therapy between January 2016 and December 2018. Descriptive statistics were calculated for all patients. Clinical, demographic, and treatment characteristics were gathered and analyzed. Kaplan-Meier curves were generated to estimate survival and recurrence rates. Outcomes assessed included 5-year overall survival (OS), 5-year local control (LC), biochemical failure (BF), regional and distant failures, and physician-reported adverse events (AEs). Biochemical failure was defined as rise in PSA ≥ 2.0 ng/mL above nadir PSA. Acute and chronic gastrointestinal (GI) and genitourinary (GU) grade 2+ and grade 3+ baseline-adjusted AEs were assigned using CTCAE v5.0. All failures were re-staged with PET C-11 or PSMA.

RESULTS

With a median follow up of 4.4 years (IQR 3.7 - 5), two hundred and eighty-six prostate cancer patients with a median age of 72 (IQR 67.5 - 77) were treated with spot-scanned proton radiation. The median Gleason grade group was 3 (IQR 2 - 4). The median pre-RT PSA was 6.9 ng/mL (IQR 4.3 - 10.5). Median T-stage was T1c. Nearly 64% of all patients were on androgen deprivation therapy at the time of initiating radiation treatment. The median total radiation dose was 79.2 Gy delivered over 44 fractions, 70 Gy over 28 fractions, and 38 Gy over 5 fractions for CF, HF, and SBRT regimens, respectively. The BF rate for all patients was 8.4%. The 5-year LC rates for CF, HF, and SBRT were 100% (95% CI: 100 - 100), 100% (95% CI: 100 - 100), and 97.3% (95% CI: 92.2 - 100), respectively (p = 0.07). Regional recurrences occurred in 12 (4.2%) patients: 8 (5.6%) treated with CF, 2 (2.1%) with HF, and 2 (4.3%) with SBRT (p = 0.62). Distant metastatic failures occurred in 12 patients (4.2%): 5 (3.5%) treated with CF, 7 (7.4%) with HF, and none with SBRT (0%) (p = 0.052). The 5-year OS for patients treated with CF, HF, and SBRT SSPT were 88.2% (95% CI: 81.8 - 95), 86.2% (95% CI: 77.6 - 95.6), and 97.2% (95% CI: 92 - 100), respectively (p = 0.1). Acute and chronic grade 2+ GI baseline-adjusted AEs occurred in 8 (2.8%) and 51 (17.8%) patients, respectively. Acute and chronic grade 3+ GI baseline-adjusted AEs occurred in 3 (1%) and 4 (1.4%) patients, respectively. Acute and chronic grade 2+ GU-related AEs were observed in 72 (25.2%) and 63 (22%) patients, respectively. Acute and chronic grade 3+ GU toxicity was observed in 3 (1%) and 6 (2.1%) patients, respectively.

CONCLUSION

Spot-scanned proton radiation therapy provides high local control rates and excellent oncologic outcomes across different fractionation schedules with low long-term AE rates.

High Resolution analysis of Transmission Dynamics of Sars-Cov-2 in Two Major Hospital Outbreaks in South Africa Leveraging Intrahost Diversity

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes acute, highly transmissible respiratory infection in both humans and wide range of animal species. Its rapid spread globally and devasting effects have resulted into a major public health emergency prompting the need for methodological interventions to understand and control its spread. In particular, The ability to effectively retrace its transmission pathways in outbreaks remains a major challenge. This is further exacerbated by our limited understanding of its underlying evolutionary mechanism. Using NGS whole-genome data, we determined whether inter- and intra-host diversity coupled with bottleneck analysis can retrace the pathway of viral transmission in two epidemiologically well characterised nosocomial outbreaks in healthcare settings supported by phylogenetic analysis. Additionally, we assessed the mutational landscape, selection pressure and diversity of the identified variants. Our findings showed evidence of intrahost variant transmission and evolution of SARS-CoV-2 after infection These observations were consistent with the results from the bottleneck analysis suggesting that certain intrahost variants in this study could have been transmitted to recipients. In both outbreaks, we observed iSNVs and SNVs shared by putative source-recipients pairs. Majority of the observed iSNVs were positioned in the S and ORF1ab region. AG, CT and TC nucleotide changes were enriched across SARS-COV-2 genome. Moreover, SARS-COV-2 genome had limited diversity in some loci while being highly conserved in others. Overall, Our findings show that the synergistic effect of combining withinhost diversity and bottleneck estimations greatly enhances resolution of transmission events in Sars-Cov-2 outbreaks. They also provide insight into the genome diversity suggesting purifying selection may be involved in the transmission. Together these results will help in developing strategies to elucidate transmission events and curtail the spread of Sars-Cov-2.

Autologous Blood Transfusion in Elective Orthopaedic Surgery

Autologous blood transfusion is one of the most effective ways of avoiding the need for homologous transfusion and all its associated complications. Since the beginning of 1985, autotransfusions have been used in 48 patients undergoing total joint replacement, without significant complications. Their average haemoglobin level two weeks postoperatively was 11.3 mg/dl. We believe that this is a safe, effective and economical procedure which benefits both patients and medical staff, and its use should be more widespread.

Beware the Emergency Ankle Fracture Referral: An Unusual Case of Lateral Subtalar Joint Dislocation Secondary to Calcaneal Fracture with associated Lateral Malleolus Fracture

Introduction:

The referral of a lateral malleolus fracture is one of the commonest orthopaedic trauma presentations. Failure to fully assess the patient and radiography can lead to missing associated injuries in the hindfoot.

Case Report:

We describe an unusual hindfoot injury with an atypical combination of lateral subtalar dislocation and calcaneal fracture with associated lateral malleolus fracture that was initially not appreciated by the referring emergency department. This case is of particular interest as subtalar dislocation is a rare injury and lateral subtalar dislocation is even rarer.

Conclusion:

Failure to fully assess such injuries and manage non-operatively leads to early degenerative tibia-talar, hindfoot and midfoot changes and a difficult situation for the surgeon to salvage. We advocate early CT scan and open reduction with fixation for such cases.

Potential subtherapeutic linezolid and meropenem antibiotic concentrations in a patient with severe burns and sepsis

Altered pharmacokinetics in patients with major burns may result in serum antibiotic concentrations below those required to be effective against the common pathogens encountered in burns patients. The major changes in the fluid volumes of key body compartments, which occur with a large burn, may increase the apparent volume of distribution of a drug, thereby lowering its concentration when a standard dose is given. In addition, the observed increase in renal blood flow reported in burns patients, because of the change in cardiac output, may result in a higher drug clearance and a shorter elimination half-life. As a consequence, studies have recommended higher doses or more frequent dosing or both for some antibiotics in patients with major burns, but data are lacking for many of the antibiotics reserved for treatment of life-threatening infections. The authors measured serum concentrations of two antibiotics, linezolid and meropenem, in an immunosuppressed patient who presented with a severe burn to determine whether therapeutic concentrations were achieved, thereby improving the likelihood of infection control.

A model for the preliminary biological screening of potential keratoprosthetic biomaterials

A series of in vitro screening assays for the preliminary selection of biomaterials for use in the fabrication of artificial corneas (keratoprostheses) (KPros) have been investigated. These screening assays assessed the initial binding of inflammatory and cell adhesive proteins, activation of inflammatory proteins, adhesion of keratocytes, epithelial cells and macrophages and the production of inflammatory cytokines by keratocytes contacting biomaterials. Central optic biomaterials were selected on the basis of low-inflammatory and cell adhesion potential. Peripheral skirt materials were selected on the basis of low-inflammatory potential but good cell adhesion to anchor the implant within the host cornea. Green fluorescent protein (GFP) gene transfer was used in a novel context to investigate cell invasion in the absence of external staining techniques. Confocal laser scanning microscopy and scanning electron microscopy were used to investigate GFP positive keratocyte invasion of porous materials. The results of in vitro assays were compared to a corneal organ culture system in which the biomaterials were assessed within a stromal environment. A range of polyurethane-based interpenetrating polymers with a range of water contents were screened. All materials showed low-inflammatory potential. A reduction in biomaterial water content induced an increase in complement C3 and fibronectin binding and in cell adhesion to materials, whilst differences in co-monomer formulation had little impact. The screening methods used in the current study provide a suitable preliminary assessment regime for the in vitro evaluation of potential KPro materials.

Survival of a 75% burn in a patient with longstanding Addison's disease

This is the first reported case of survival of a significant burn in a patient with established Addison's disease. The systemic stress response to thermal injury is well recognised, there is a marked hypermetabolic response with prolonged periods of catabolism. In particular, the elevation of plasma cortisol levels is crucial for this response to severe systemic stress. Cortisol elevation is maintained for the duration of burn wound healing, is proportional to the burned body surface area and the normal circadian rhythm of endogenous cortisol is lost. Acute adrenal insufficiency has been described in patients suffering major burn injuries with generally poor outcomes. We discuss the management and complications of adrenal replacement therapy in a severe burn setting, as illustrated by this case report.

The Soho nail bomb: the UCH experience. University College Hospital

This paper documents the clinical course of the casualties treated at University College Hospital, following the detonation of a terrorist nail bomb in a public house in Soho, London. The need for adequate primary debridement is paramount, including consideration of definitive primary limb amputation.

The potential for eye bank limbal rings to generate cultured corneal epithelial allografts

PURPOSE

Patients with severe limbal deficiencies are unable to maintain a stable corneal surface. If sheets of cultured allogeneic corneal epithelium could be prepared from eye banked corneal limbal rings, which are normally discarded after keratoplasty, the sheets may be beneficial for grafting onto patients with limbal stem cell deficiencies.

METHOD

Biopsies of limbal tissue (2-3 mm2) removed from organ-cultured corneal limbal rings or from fresh whole globes were either trypsinized or set up as explants to assess their potential for corneal epithelial cell production.

RESULTS

Several biopsies were taken from each of 21 organ-cultured limbal rings and 10 fresh cadaveric globes. Cultures were generated from every cadaveric eye (10/10), although not all biopsies from the same eye gave rise to cultures. Confluent sheets of cultured cells were also produced successfully from limbal rings that had been in organ culture for up to 25 days, but the success rate from limbal ring material was variable (14/21). An analysis of parameters associated with each limbal ring was carried out in an attempt to identify the reasons for the different efficiencies of epithelial production. No obvious single parameter correlation was detected, although there was a trend to poorer efficiency with increased donor age.

CONCLUSIONS

Confluent sheets of cultured corneal epithelial cells, suitable for grafting, can be produced from limbal tissue taken from eye bank organ-cultured corneas, although it takes longer, on average, to reach confluence (17-21 days) than an equivalent sample from a fresh eye (9-12 days).

Werner's syndrome T lymphocytes display a normal in vitro life-span

Werner's syndrome (WS) is an autosomal recessive disorder displaying many features consistent with accelerated ageing. Fibroblasts from WS patients show a distinct mutator phenotype (characterised by the production of large chromosomal deletions) and a profound reduction in proliferative capacity. The disorder results from a mutation in a novel ReqQ helicase. Recently, we demonstrated that the proliferative defect was corrected by the ectopic expression of telomerase. From these data, we propose that mutations in the wrn gene lead to deletions at or near the telomere which reduce the cells replicative life-span. This hypothesis predicts that cell types which retain the ability to upregulate telomerase as part of their response to a proliferative stimulus would fail to show any significant effect of wrn gene mutations upon life-span. Human T lymphocytes represent a well-characterised example of such a cell type. To test the hypothesis, WS T lymphocytes were cultured until they reached replicative senescence. These cultures displayed life-spans which did not differ significantly from those of normal controls. These findings are consistent with the hypothesis that the effects of wrn mutations on replicative life-span are telomere-mediated.

Low-friction arthroplasty with Boneloc bone-cement: outcome at 2 to 4 years

We report the clinical and radiologic outcome of 109 Chamley low-friction arthroplasties implanted with Boneloc bone-cement (Biomet, Bridgend, South Wales, UK) into 104 patients. The mean follow-up was 30 months (range, 2-48 months). There were 72 women (mean age, 71 years) and 32 men (mean age, 72). Cartridge-packed cement was used in 37 cases and vacuum-packed cement in 72 cases. Survivorship analysis based on revision for aseptic loosening showed 79% survival at 4 years. Seventeen (15.5%) hips have been revised for aseptic loosening to date, in which all stems and 4 cups were loose. Extensive femoral osteolysis was always present and resulted in 4 cases of femoral cortical perforation at revision. Survivorship analysis based on revision and radiologic failure showed only 55% survival over the same period. When radiologic loosenings were included as failures, the vacuum-packed cement performed significantly worse than the cartridge-packed cement it replaced. These poor results were consistent with the withdrawal of Boneloc from clinical use in 1995, and we recommend indefinite follow-up for surviving prostheses.

Fulfilling the promise: community response to the needs of sexual minority youth and families

Gay, lesbian, bisexual, transgendered, and questioning youth, and the children of gay and lesbian parents, are particularly vulnerable to harassment and other forms of risk. This paper reviews the literature and outlines common processes beginning to be used in some U.S. communities to meet the needs of these youth and families. An illustration of progressive community action is offered in the case of a church-initiated effort still ongoing in a small town in Massachusetts.

Postoperative radiographs or thermal prints after internal fixation of fractures? A study of DHS fixation of hip fractures

Immediate postoperative radiographs confirm the quality of reduction and fixation of fractures. This information is already available from the image intensifier and can be saved as hard copy thermal prints. If thermal prints give the surgeon the necessary patient and clinical information them immediate postoperative radiography should not be required. In this retrospective study of 20 hip fractures treated by dynamic hip screw (DHS) fixation, plain radiographs and thermal prints were compared for the patient and clinical information they contained. Thermal prints were found to be deficient in some areas but, nevertheless, can potentially replace postoperative radiographs in many orthopaedic procedures saving time, money and radiation exposure.

Mennen plate fixation for fracture of the femoral shaft with ipsilateral total hip and knee arthroplasties

A method of treatment for a femoral shaft fracture in a patient with well-functioning ipsilateral total hip and knee arthroplasties is described. Total hip and knee arthroplasties are commonly performed, but ipsilateral femoral shaft fracture is an infrequent and troublesome complication. Management of these fractures is often difficult. Various operative treatments have been described in the literature with varying success.

The non-operative management of radial head fractures: a randomized trial of three treatments

Ninety-eight consecutive patients with Mason type 1 and 2 radial head fractures were randomized into three treatment groups to compare early mobilization with immobilization in flexion and extension. Eighty-one patients were reviewed on average 25 months following fracture and assessed for pain, disability and range of movement. Loss of full extension was the most frequent restriction of movement and was found in 17 patients. Two patients had restricted flexion without limited extension. Patients immobilized in a flexion cast had a significantly reduced range of movement compared with patients immobilized in extension (P = 0.02). Nineteen patients had residual pain and again the flexion group fared worse than the extension group (P = 0.06). Results from early mobilization in a sling were not significantly different from the other two groups. Treatment of radial head fractures in flexion casts should be avoided.

Three-dimensional CT imaging of the wrist. A practical system

Three-dimensional computerized tomography provides a new approach to radiological imaging. Raw data from sequential two-dimensional scans have been reconstructed as a three-dimensional model of the carpal area using the Medical Graphics and Imaging Workstation. This study demonstrates the anatomical accuracy and potential diagnostic qualities of a reconstruction of the carpus using this system. The advantages, pitfalls and suggested applications of this technique of carpal imaging are discussed. Three-dimensional imaging is shown to provide a great deal of information which cannot be viewed on conventional radiographs or CT images.

Pelvic underpinning: eight years' experience

A new method to reconstruct major acetabular floor defects is described. It relies on the placement of special nails into each of the three bones of the hemipelvis. Curved lugs attached to the nails are coalesced using bone cement forming a platform onto which a standard acetabular prosthesis is located. Forty-seven cases are reported with a mean follow-up of 4.4 years (1 to 8). No loosening of an acetabular cup or migration of the device has occurred.

Bi-articular hemiarthroplasty of the hip: a 7-year follow-up

A bi-articular prostheses was used to replace the femoral head in 323 patients over 7 years in an attempt to reduce the incidence of acetabular erosion, which has been reported by others who have used different types of prostheses. No erosion of the acetabulum has yet been found in our series, but from the point of view of cost, we consider that the use of this prosthesis should be restricted to active younger patients.

Percutaneous disc surgery

The rationale and clinical methods of percutaneous disc surgery have been modified during the past four years. Experience with a consecutive series of 48 patients suggests that the procedure now offers results comparable to open surgery and the advantages of reduced surgical trauma.

Comparative human cellular radiosensitivity: II. The survival following gamma-irradiation of unstimulated (G0) T-lymphocytes, T-lymphocyte lines, lymphoblastoid cell lines and fibroblasts from normal donors, from ataxia-telangiectasia patients and from ataxia-telangiectasia heterozygotes

We have measured clonal survival following gamma-irradiation of unstimulated (G0) T-lymphocytes from 35 donors, of 11 T-lymphocyte cell lines, of six lymphoblastoid cell lines, and of nine primary fibroblast strains for which we have G0 T-lymphocyte material from the same donor. Amongst the G0 lymphocytes we have results from nine normal donors, from eight cord bloods, from seven ataxia-telangiectasia (A-T) patients and from nine A-T heterozygotes. Although there is some variation between samples, G0 T-lymphocytes from normal donors appear to be slightly more radioresistant than T-lymphocyte lines, with a more shouldered survival curve. From our limited sample, lymphoblastoid cell lines appear to be slightly more radiosensitive than T-lymphocytes. The overall radiosensitivity of primary fibroblasts appears to be broadly similar to that of G0 T-lymphocytes. In nine instances, five A-Ts and four A-T heterozygotes, both G0 T-lymphocytes and primary fibroblasts from the same donor were tested. In five cases there was closely similar radiosensitivity in the two cell types, but in four cases there was some discrepancy. Further work, especially with normal donors, will be required in order to establish how reliably radiosensitivity in other cell types can be predicted from that of G0 T-lymphocytes. In all cell types the hypersensitivity of A-T cells was confirmed. Furthermore, the marginally greater sensitivity of A-T heterozygotes, when compared as a group with normals, was confirmed with G0 T-lymphocytes. Our results also suggest a slightly increased radiosensitivity in G0 T-lymphocytes from some, but not all, cord blood samples.

A further assessment of factors influencing measurements of thioguanine-resistant mutant frequency in circulating T-lymphocytes

We have used the T-Lymphocyte cloning technique as a method of monitoring the human population for somatic cell mutant frequency. We present a statistical analysis of the experimental factors which may influence the observed mutant frequency. We have obtained consistently high plating efficiencies of T-cells from the mononuclear cell fraction from donor blood samples (mean of 56%, based on 123 observations from 70 individuals). Nevertheless, an inverse correlation of mutant frequency with plating efficiency was observed, and some experimental factors (serum and interleukin-2 batch, and worker) may have a significant effect on the observed mutant frequency. We discuss the difficulties that these possible effects present in establishment of a reference database and design of long-term studies. No significant effect of donor sex on mutant frequency was observed, but age (1.3% increase per year for normal adults) and smoking (56% increase over normal non-smokers) both significantly increased the mutant frequency. We discuss the utility of the assay for the monitoring of populations for heritable DNA damage, and we compare the results to those obtained with lymphocytes using other endpoints, e.g. chromosome aberrations, micronuclei and sister-chromatid exchange.

Detection of somatic mutations in man: evaluation of the microtitre cloning assay for T-lymphocytes

A method of detecting 6-thioguanine-resistant lymphocytes by the cloning of T-lymphocytes in microtitre wells is evaluated for its usefulness in population monitoring. Factors shown to affect the cloning efficiency of lymphocytes include the strain and irradiation level of the lymphoblastoid feeder cells and the use of a pre-incubation period in bulk culture without mitogenic stimulus before plating at limiting dilutions. Cord blood samples have markedly lower mutant frequencies than adult blood samples. The adult range was 8.0 X 10(-7) to 1.8 X 10(-5). Seven males and seven females aged between 23 and 47 years were sampled. No effect of sex or age was found. Individual samples which were divided at collection and treated separately did not vary from each other, but repeat samples taken at different times showed up to a 2-fold variation. The application of this method in population monitoring is discussed.

Experience using the carbon dioxide laser in the removal of cutaneous tattoos

A preliminary study was undertaken to determine if the carbon dioxide laser was a suitable technique for the removal of tattoos. Twenty-eight patients with 47 tattoos had their tattoos removed by the carbon dioxide laser. The results were assessed by an independent observer 1 year after completion of treatment. The most satisfactory results were obtained in patients with discrete linear tattoos of amateur origin. In those with polychromatic blocked-in tattoos of professional origin, hypertrophic scars occurred and the overall result was unsatisfactory.

A complicated case of mitral valve disease

A patient with rheumatic mitral stenosis and previous cerebral embolism had a myocardial infarction during cardiac catheterisation. She later developed severe mitral regurgitation one year after open valvotomy and at valve replacement was found to have a papillary tumour of the mitral valve. Unexplained low cardiac output occurred four days after operation. Postmortem examination showed thrombotic occlusion of the xenograft prosthesis, a complication not previously seen with tissue valves. Both of these rare events were suggested by the patient's clinical course and could have been diagnosed with cross sectional echocardiography.

Back pain in athletes

There were one hundred and ninety seven patients who presented with back pain to an Athletes Clinic over four years. Their mode of presentation, investigations, diagnoses and treatments are analysed. The majority of patients were male and below 30 years of age. The average duration of symptoms prior to presentation, despite an easy access policy, was 42 weeks. Injury was usually related to six popular sports. Radiological examination was a rewarding investigation in these patients and included an A-P view of the pelvis. The diagnostic label of prolapsed intervertebral disc appears to have been used too frequently. Physiotherapy was the most useful treatment modality regardless of age, mode of onset and duration of symptoms.

Radiosensitivity of human T-lymphocytes proliferating in long term culture

A method is described for determining the radiation sensitivity of dividing human T-lymphocytes in long-term culture. The results are fitted to a single-hit multi-target model. For cobalt-60 gamma radiation Do values of cells from five normal individuals range from 0.99 to 1.37 Gy with an overall Do of 1.09 Gy, and the extrapolation numbers range from 1.20 to 1.71 with an overall extrapolation number of 1.42.

Failure to detect autologous antibodies in the remission sera of patients with AML: complications introduced by the presence of rheumatoid factor

Sera were collected from patients with acute myelogenous leukaemia (AML) at various times during remission induced by chemotherapy, but after cessation of all immunosupressive treatment. These sera were tested, by a sensitive assay using radio-labelled antiglobulin binding, for the presence of antibodies which bound to the surface of autologous AML cells. The cell populations examined were chosen on the basis that they proliferated in short-term culture, did not bind anti-Ig reagents directly, and that more than 80% of the cells did not carry detectable Fc receptors. With 8/9 patients studied, no specific antibodies of the IgG or IgM class could be detected in serum samples taken during remission. IgG and IgM antibodies from the remission sera of one patient were found be bind to autologous leukaemic cells, but this was found to be due to the presence of rheumatoid factor (RF) and removal of the RF activity abolished this binding. This study has, like others, failed to detect autologous antibodies, in remission sera, that are directed against membrane components of AML cells.

Comparison of radiotherapy with and without razoxane (ICRF 159) in the treatment of soft tissue sarcomas

Comparison of the recurrence rates of soft tissue sarcomas treated by radiotherapy (14 patients) or radiotherapy and synchronous administration of razoxane (19 patients) has shown a statistically significant benefit for those patients treated by the combination. No increase in tissue reactions or adverse side-effects (apart from a readily reversible leukopenia) was observed. The implication is that razoxane acts as a well tolerated adjuvant for radiotherapy.

Training the secretary in community mental health: a second model for integrating secretaries into the therapeutic team in community mental health

The secretaries in community mental health centers have functions that transcend their job descriptions. Their performance of these functions contributes to the success or failure of their centers' therapeutic programs. The Mental Health Training Institute of North Carolina initiated two separate pilot training programs within 1971-1972, aimed at heightening the secretaries' appreciation of their role within their centers and at facilitating their integration into the therapeutic team. This paper is a discussion of the second of these two programs.