Quality assurance for the clinical implementation of kilovoltage intrafraction monitoring for prostate cancer VMAT

PURPOSE

Kilovoltage intrafraction monitoring (KIM) is a real-time 3D tumor monitoring system for cancer radiotherapy. KIM uses the commonly available gantry-mounted x-ray imager as input, making this method potentially more widely available than dedicated real-time 3D tumor monitoring systems. KIM is being piloted in a clinical trial for prostate cancer patients treated with VMAT (NCT01742403). The purpose of this work was to develop clinical process and quality assurance (QA) practices for the clinical implementation of KIM.

METHODS

Informed by and adapting existing guideline documents from other real-time monitoring systems, KIM-specific QA practices were developed. The following five KIM-specific QA tests were included: (1) static localization accuracy, (2) dynamic localization accuracy, (3) treatment interruption accuracy, (4) latency measurement, and (5) clinical conditions accuracy. Tests (1)-(4) were performed using KIM to measure static and representative patient-derived prostate motion trajectories using a 3D programmable motion stage supporting an anthropomorphic phantom with implanted gold markers to represent the clinical treatment scenario. The threshold for system tolerable latency is <1 s. The tolerances for all other tests are that both the mean and standard deviation of the difference between the programmed trajectory and the measured data are <1 mm. The (5) clinical conditions accuracy test compared the KIM measured positions with those measured by kV/megavoltage (MV) triangulation from five treatment fractions acquired in a previous pilot study.

RESULTS

For the (1) static localization, (2) dynamic localization, and (3) treatment interruption accuracy tests, the mean and standard deviation of the difference are <1.0 mm. (4) The measured latency is 350 ms. (5) For the tests with previously acquired patient data, the mean and standard deviation of the difference between KIM and kV/MV triangulation are <1.0 mm.

CONCLUSIONS

Clinical process and QA practices for the safe clinical implementation of KIM, a novel real-time monitoring system using commonly available equipment, have been developed and implemented for prostate cancer VMAT.

Determining appropriate imaging parameters for kilovoltage intrafraction monitoring: an experimental phantom study

Kilovoltage intrafraction monitoring (KIM) utilises the kV imager during treatment for real-time tracking of prostate fiducial markers. However, its effectiveness relies on sufficient image quality for the fiducial tracking task. To guide the performance characterisation of KIM under different clinically relevant conditions, the effect of different kV parameters and patient size on image quality, and quantification of MV scatter from the patient to the kV detector panel were investigated in this study. Image quality was determined for a range of kV acquisition frame rates, kV exposure, MV dose rates and patient sizes. Two methods were used to determine image quality; the ratio of kV signal through the patient to the MV scatter from the patient incident on the kilovoltage detector, and the signal-to-noise ratio (SNR). The effect of patient size and frame rate on MV scatter was evaluated in a homogeneous CIRS pelvis phantom and marker segmentation was determined utilising the Rando phantom with embedded markers. MV scatter incident on the detector was shown to be dependent on patient thickness and frame rate. The segmentation code was shown to be successful for all frame rates above 3 Hz for the Rando phantom corresponding to a kV to MV ratio of 0.16 and an SNR of 1.67. For a maximum patient dimension less than 36.4 cm the conservative kV parameters of 5 Hz at 1 mAs can be used to reduce dose while retaining image quality, where the current baseline kV parameters of 10 Hz at 1 mAs is shown to be adequate for marker segmentation up to a patient dimension of 40 cm. In conclusion, the MV scatter component of image quality noise for KIM has been quantified. For most prostate patients, use of KIM with 10 Hz imaging at 1 mAs is adequate however image quality can be maintained and imaging dose reduced by altering existing acquisition parameters.

Association between absolute tumor burden and serum bone-specific alkaline phosphatase in canine appendicular osteosarcoma

BACKGROUND

In dogs with appendicular osteosarcoma (OSA), increased pretreatment serum bone-specific alkaline phosphatase (BALP) activity is a negative prognostic factor, associated with shorter disease-free intervals and survival times, but a biologic basis for observed differential serum BALP activities in canine OSA patients remains incompletely defined.

OBJECTIVE

Serum BALP activity will correlate with absolute tumor burden in dogs with OSA.

ANIMALS

This study included 96 client-owned dogs with appendicular OSA.

METHODS

In canine OSA cell lines, the expression and membranous release of BALP was evaluated in vitro. The correlation between serum BALP activity and radiographic primary tumor size was evaluated in OSA-bearing dogs. In dogs developing visceral OSA metastases, serial changes in serum BALP activities were evaluated in relation to progression of macroscopic metastases, and visceral metastatic OSA cells were evaluated for BALP expression.

RESULTS

In vitro, BALP expression was not associated with either tumorigenic or metastatic phenotype, rather the quantity of membranous BALP released was proportional with cell density. In dogs devoid of macroscopic metastases, there was a positive correlation between serum BALP activity and absolute primary tumor size. In dogs with progressive OSA metastases, serum BALP activity increased and coincided with the development of macroscopic metastases. OSA cells derived from visceral metastatic lesions retained BALP expression.

CONCLUSIONS AND CLINICAL IMPORTANCE

Tumor burden is a determinant of serum BALP activity in dogs with appendicular OSA. The association between increased pretreatment BALP activity and negative clinical prognosis may simply be attributed to greater initial tumor burden, and consequently more advanced tumor stage.

Ultrasonographic evaluation of the thickness of the small intestinal wall in dogs with inflammatory bowel disease

OBJECTIVES

To establish whether the intestinal wall thickness, as measured ultrasonographically, is significantly increased in dogs with inflammatory bowel disease (IBD). The results would provide the information necessary to decide whether measurement of ultrasonographic wall thickness can predict IBD in dogs.

METHODS

The intestinal wall thickness of 75 dogs with idiopathic IBD, as measured by ultrasonography, was compared with recently published normal values. IBD was either confirmed histologically (n = 54) or suspected (n = 21). In all cases there was a positive response to immunosuppressive treatment.

RESULTS

A positive association between intestinal wall thickness in dogs and either the histological diagnosis or the response to treatment was not found. Ultrasonographic intestinal wall measurements do not appear to be able to establish a diagnosis of intestinal inflammation and may result in a false negative diagnosis in cases of IBD.

CLINICAL SIGNIFICANCE

The same 'grey zone' of between 4 and 6 mm used in humans can be used in the canine duodenum to distinguish the normal range, reserving the term 'abnormal' for an intestinal measurement greater than 6 mm in the duodenum and greater than 4.7 mm in the jejunum.

CONTRAST HARMONIC ULTRASOUND OF SPONTANEOUS LIVER NODULES IN 32 DOGS

Thirty-two dogs with spontaneous hepatic nodules were given intravenous ultrasound contrast medium (Definity or Sonovue) and imaged with contrast harmonic software on a conventional ultrasound machine system. Digital video images were initially reviewed to describe the perfusion pattern of malignant nodules. The images were reviewed again to test this pattern against all individual nodules. Subjectively, there was improved conspicuity of malignant nodules after contrast enhancement compared with conventional imaging and increased numbers of malignant nodules were often noted. There was decreased conspicuity of benign nodules and no additional nodules were seen after contrast enhancement. There was a highly significant (P < 0.0001) association of malignancy with a hypoechoic nodule at surrounding normal liver peak contrast enhancement. Benign nodules were isoechoic to the surrounding normal liver at peak contrast enhancement. Only one benign nodule (hepatoma) had regions of hypoechogenicity compared with the surrounding normal liver at peak liver contrast enhancement. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were highly significant (P < 0.0001) (100%, 94.1%, 93.8%, 100%, and 96.9%, respectively). No complications or morbidity was noted throughout the course of the study. Contrast harmonic ultrasound appears to be accurate at discriminating between naturally occurring benign and malignant nodules in the liver of dogs.

Ultrasonographic appearance of exogenous isobutane gas in the mammary glands of dairy cows

OBJECTIVE

To determine whether exogenous isobutane gas infused into the udders of dairy cattle could be detected ultrasonographically, and if so, what effects volume of gas infused and infusion pressure had on how long after infusion exogenous isobutane gas could be detected.

DESIGN

Randomized block design.

ANIMALS

8 Holstein cows 28 to 32 days after parturition.

PROCEDURE

In each cow, 1 mammary gland was not treated and the other 3 received 1 of 3 treatments by means of intramammary infusion: low volume-high pressure, low volume-low pressure, and high volume-high pressure infusion of isobutane gas. Mammary glands were examined ultrasonographically 1 hour before and 1, 3, 12, 24, 36, 48, 72, and 96 hours after treatment.

RESULTS

After intramammary infusion of isobutane gas, bright echoes and associated acoustic shadows were seen ultrasonographically; echoes were no longer seen 72 hours after gas infusion. Percentages of mammary glands in which bright echoes were detected were not significantly different among the 3 treatment groups at any time during the study.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that exogenous isobutane gas infused into the mammary glands to enhance the appearance of the udder of show dairy cattle can be readily detected by ultrasonography.

Pancreatic pseudocysts in 4 dogs and 2 cats: ultrasonographic and clinicopathologic findings

Pancreatic pseudocysts were diagnosed in 4 dogs and 2 cats based on ultrasonographic and clinicopathologic findings. All 6 animals had a clinical diagnosis of pancreatitis. Five of 6 pseudocysts were in the left pancreatic limb, and in 1 cat the pseudocyst was in the pancreatic body region. Cyst size ranged from 2 x 2 cm to 7 x 6 cm. All pseudocysts had anechoic regions that were aspirated using ultrasound guidance for diagnostic and therapeutic purposes. No morbidity was associated with the aspiration procedures. Cytologically the pseudocyst fluid was aseptic in all patients and had low numbers of inflammatory cells in 5 of 6 patients. All animals had high lipase activity in the pseudocyst fluid and in 2 dogs and 1 cat the lipase activity in the fluid was greater than in serum. Three of the 4 dogs were managed medically. In the 1 dog that had long-term follow-up ultrasound examination, the pseudocyst persisted for several days following aspiration and had disappeared 8 months after diagnosis. All 3 of these dogs were clinically normal 1.5-4 years after presentation. The 4th dog underwent surgical exploration and was euthanized shortly thereafter because of bronchopneumonia and chronic pancreatitis. The 2 cats died 10 days and 2 months, respectively, following initial diagnosis of the pseudocyst, but necropsies were not performed in either case. Ultrasound-guided fine-needle aspiration of pancreatic pseudocysts and clinicopathologic evaluation of cystic fluid are useful for diagnosis of pancreatic pseudocysts.

Ultrasonography and fine needle aspirate cytology of the mesenteric lymph node in normal domestic ferrets (Mustela putorius furo)

The large mesenteric lymph node of 28 normal ferrets was imaged with ultrasound. The large node, located in the mid-abdomen at the root of the mesentery, was round to ovoid and uniformly hyperechoic. Mean ultrasonographic dimensions of the lymph node were 12.6 +/- 2.6 mm by 7.6 +/- 2.0 mm. Fine needle aspirates of 20 lymph nodes were obtained either using ultrasound guided free-hand techniques or at necropsy. The cytological descriptions were compared to histological descriptions of 13 lymph node core biopsies obtained during laparotomy or necropsy as well as 10 peripheral blood smear differentials. The large mesenteric lymph node of ferrets could be easily imaged and measured by ultrasound and evaluated by fine needle aspirate cytology. Normal lymph node cytology may include an eosinophilic infiltrate.

Treatment outcome and prognostic factors for infants with acute lymphoblastic leukemia treated on two consecutive trials of the Children's Cancer Group

PURPOSE

Infants represent a very poor risk group for acute lymphoblastic leukemia (ALL). We report treatment outcome for such patients treated with intensive therapy on consecutive Children's Cancer Group (CCG) protocols.

PATIENTS AND METHODS

Between 1984 and 1993, infants with newly diagnosed ALL were enrolled onto CCG-107 (n = 99) and CCG-1883 (n = 135) protocols. Postconsolidation therapy was more intensive on CCG-1883. On both studies, prophylactic treatment of the CNS included both high-dose systemic chemotherapy and intrathecal therapy, in contrast to whole-brain radiotherapy, which was used in earlier studies.

RESULTS

Most patients (>95%) achieved remission with induction therapy. The most frequent event was a marrow relapse (46 patients on CCG-107 and 66 patients on CCG- 1883). Four-year event-free survival was 33% (SE = 4.7%) on CCG-107 and 39% (SE = 4.2%) on CCG- 1883. Both studies represent an improvement compared with a 22% (SE = 5.1%) event-free survival for historical controls. Four-year cumulative probabilities of any marrow relapse or an isolated CNS relapse were, respectively, 49% (SE = 5%) and 9% (SE = 3%) on CCG-107 and 50% (SE = 5%) and 3% (SE = 2%) on CCG-1883, compared with 63% (SE = 6%) and 5% (SE = 3%) for the historical controls. Independent adverse prognostic factors were age less than 3 months, WBC count of more than 50,000/microL, CD10 negativity, slow response to induction therapy, and presence of the translocation t(4;11).

CONCLUSION

Outcome for infants on CCG-107 and CCG- 1883 improved, compared with historical controls. Marrow relapse remains the primary mode of failure. Isolated CNS relapse rates are low, indicating that intrathecal chemotherapy combined with very-high-dose systemic therapy provides adequate protection of the CNS. The overall unsatisfactory outcome observed for the infant ALL population warrants the future use of novel alternative therapies.

Ultrasound-guided fine-needle aspiration of focal parenchymal lesions of the lung in dogs and cats

Ultrasound-guided fine-needle aspiration (FNA) of the lung was performed on 16 dogs and 3 cats with consolidated pulmonary lesions or masses identified on thoracic radiographs. The cytologic results from the FNA were confirmed by histopathology, response to treatment, or microscopic identification of Blastomyces organisms. Neoplasia was identified correctly by FNA cytology in 10 of 11 animals, and no false positive results occurred, yielding a positive predictive value of 100%. Of 8 animals with infectious disease, 5 of 6 had blastomycosis and 1 had a bacterial infection, based on cytologic evaluation. Eight animals required sedation for the procedure, and none had clinical complications. We conclude that ultrasound-guided FNA of pulmonary mass lesions is an inexpensive, safe, and accurate method for diagnosing blastomycosis or neoplasia, especially carcinomas, in dogs and cats.

Dental imaging

Radiography continues to be the initial test of choice in equine dental imaging for reasons of availability and ability to detect bone and tooth changes. Contrast radiography may be useful to characterize dental involvement in cases with draining tracts. For radiographically occult lesions, other modalities are useful. CT is better than plain radiography due to the inherent avoidance of superimposition of the opposite dental arcade, excellent bone density characterization, and good spatial resolution. Nuclear medicine may be useful to verify bone involvement in the dental region in cases in which the signs are particularly vague or not readily localized. Ultrasonography is an excellent test for soft tissue characterization and may assist with the characterization of suspected bone lysis, pathologic fractures, and abscesses.

Sonographic renal findings in 20 dogs with leptospirosis

Abdominal ultrasound examinations of 20 dogs with confirmed leptospirosis were reviewed retrospectively for renal abnormalities. Three dogs had a normal ultrasound examination. The remaining 17 dogs had sonographic abnormalities of the kidneys. These abnormalities, seen either alone or in combination, included renalmegaly (n=10), pyelectasia (n=9), increased cortical echogenicity (n=15), perinephric effusion (n=5), and a medullary band of increased echogenicity (n=6). At our institution, the medullary band of increased echogenicity has only been seen in dogs with leptospirosis and may therefore be a specific sonographic sign for this disease.

Early detection of canine hip dysplasia: comparison of two palpation and five radiographic methods

Hip joint laxity was evaluated in four breeds (i.e., greyhound, Labrador retriever, Irish setter, hound mixed-breed) of puppies (n=32) by Ortolani's and Bardens' maneuvers, by subjective assessment of radiographs (Orthopedic Foundation for Animals [OFA] method), and by four radiographic measurement indices. Puppies were studied at four, six-to-10, 16-to-18, and 52 weeks of age. The purpose of this study was to compare palpation and radiographic methods of hip laxity detection in puppies for predicting the development of degenerative joint disease (DJD) by one year of age. Twenty-seven (42%) hips developed DJD. Ortolani's method was not a reliable predictor of hip dysplasia at six-to-10 weeks; it was significantly predictive at 16-to-18 weeks but had a high incidence of false negatives. Bardens' and subjective (OFA) assessment methods were not reliable at six-to-10 or 16-to-18 weeks. Radiographic measurements taken with femurs in a neutral position and hips distracted (distraction index [DI] and Norberg angle) and measurements taken with femurs extended in OFA position (Norberg angle) of six- to 10-week-old puppies accurately predicted DJD occurrence by one year of age (p less than 0.01). Distraction index measurement (PennHIP method) was the most accurate in predicting the development of DJD (p less than 0.001). Distraction index radiography in puppies six-to-10 and 16-to-18 weeks of age was the most reliable predictor of hip dysplasia. Norberg angle measurement was more reliable during hip distraction than when hips were measured in the OFA position in 16- to 18-week-old puppies, but had similar reliability in six- to 10-week-old puppies.

Urinary bladder mural hemorrhage associated with systemic bleeding disorders in three dogs

The sonographic appearance of three dogs with diffuse bladder wall thickening due to mural hemorrhage is described. Two dogs were diagnosed with immune-mediated thrombocytopenia and the third dog with vitamin K antagonist toxicity. Urinary bladder wall thickening ranged from 5 to 12 mm on initial sonographic examination. In the two surviving dogs, the bladder wall returned to normal thickness. One dog, euthanatized for refractory hematuria, had submucosal hemorrhage in the urinary bladder at necropsy. Urinary wall thickening sonographically resolved at a rate of approximately 1 mm per day. Mural hemorrhage should be considered in patients with concurrent bleeding disorder and urinary bladder wall thickening.

MOPP or radiation in addition to ABVD in the treatment of pathologically staged advanced Hodgkin's disease in children: results of the Children's Cancer Group Phase III Trial

PURPOSE

A randomized trial designed to compare mechlorethamine, vincristine, procarbazine, and prednisone (MOPP)/doxorubicin, bleomycin, vinblastine, and daccarbazine (ABVD) (regimen A) with ABVD plus low-dose regional (extended-field) radiation therapy (EF RT) (regimen B) for the treatment of children and adolescents with stages III and IV Hodgkin's disease was conducted by the Children's Cancer Group (CCG-521) from 1986 until 1990.

PATIENTS AND METHODS

One hundred eleven eligible patients were randomized, 57 to regimen A and 54 to regimen B. All patients had pathologically verified stage III or stage IV Hodgkin's disease.

RESULTS

Overall survival (S) is 87% at 4 years and event-free survival (EFS) is 82%. Patients randomized to ABVD plus EF RT have a 4-year EFS of 87% compared with 77% for patients randomized to MOPP/ABVD (P = .09, two-sided). Patients randomized to ABVD plus EF RT have a 4-year S of 90% compared with 84% for patients randomized to MOPP/ABVD (P = .45, two-sided). Significant prognostic factors in multivariate analysis for EFS are stage of disease, erythrocyte sedimentation rate (ESR) at diagnosis, liver size at diagnosis, and, among stage III patients, the size of the mediastinal mass at diagnosis. The acute toxicities of treatment are largely hematopoietic in nature, whereas acute pulmonary and cardiac toxicities are modest and not limiting.

CONCLUSION

The results of this study show that, in advanced-stage Hodgkin's disease in children, equivalent results can be obtained by the addition of either MOPP or low-dose EF RT to the ABVD regimen; whether the addition of either contributes to outcome was not addressed in this study and will require additional testing. It is clear, however, that MOPP chemotherapy can safely be eliminated from front-line combination chemotherapy regimens for advanced Hodgkin's disease in pediatric patients.

Quantitative ultrasonography of the liver in cats during obesity induction and dietary restriction

A study was designed to evaluate quantitative ultrasonographic characteristics of a diffuse parenchymal disease in an experimental model of subclinical fatty infiltration of the liver using diet-induced obesity and dietary restriction in the cat. Ultrasound images of livers were quantitatively analysed by a video signal analysis technique before, during and at the end of obesity induction, and then during and following dietary restriction. Attenuation and brightness (backscatter coefficient) were correlated with hepatic lipid content obtained from the livers by surgical and ultrasound-guided percutaneous biopsy. Attenuation and backscatter increased as hepatic lipid content increased. Both attenuation and backscatter significantly correlated with the hepatic lipid content (P=0.002 and P=0.02 respectively). This model of subclinical fatty infiltration of the liver in the cat demonstrates that hepatic lipid content increases as a consequence of obesity and of severe dietary restriction. Infiltration of the liver with fat may be evaluated non-invasively using quantitative ultrasonography by the video signal analysis technique. This method of image analysis may prove useful for the evaluation of diffuse parenchymal organ disease.

Qualitative ultrasonography of the liver in obese cats

A prospective study was undertaken to compare the relative echogenicity of the liver and the fat of the falciform ligament in two groups of clinically normal obese cats. In the first group of cats, four of eight normal weight cats were fed a high calorie diet ad libitum for a 12 week period at which time they were considered obese. The liver was hyperechoic when compared to the adjacent fat of the falciform ligament in the obese cats. In the second group of cats, the body condition of a group of eight clinically normal cats was subjectively graded. On ultrasonographic examination, the liver of those cats considered to be overweight were hyperechoic compared to the adjacent fat of the falciform ligament. Results from this study suggest that clinically normal obese cats may have a liver that is hyperechoic relative to the fat of the falciform ligament.

Field imaging of the respiratory tract. Radiology and ultrasonography

This article addresses the current status and clinical opportunities for portable radiography and ultrasonography. Radiology is indicated for imaging the nasal cavity, larynx, pharynx and thin portions of the neck. In young foals, adequate radiographs of the entire respiratory tract may be possible. Ultrasonography is indicated in superficial parts of the head and neck, the pleural space and diseased parts of the lungfields.

Dynamic ultrasonographic measurement of passive coxofemoral joint laxity in puppies

A new method of dynamic ultrasonographic evaluation of passive coxofemoral joint laxity was used to examine a total of 30 greyhound (n = 13) and nongreyhound (n = 17) puppies. Puppies were evaluated sonographically at four, six, eight, 12, 16, and 26 weeks of age. The coxofemoral joints were distracted manually, and the femoral head displacements were measured during distraction. The greyhounds had significantly smaller (p less than 0.01) maximum distraction distance (mean +/- standard deviation [SD], 0.11 +/- 0.04 cm) than nongreyhound puppies (mean +/- SD, 0.26 +/- 0.10 cm). In six- to eight-week-old puppies, the maximum distraction distance was correlated significantly (p of 0.0001, adjusted correlation coefficient [r2] of 0.27) with stress radiographic indices. Coxofemoral joints interpreted as being abnormal on hip-extended radiographs taken at one year of age were associated significantly (p of 0.0001) with higher maximum distraction distances in six- to eight-week-old puppies.

Ultrasound attenuation and backscatter in the liver during prednisone administration

Ultrasound attenuation and backscatter changes resulting from glucocorticoid administration were investigated in a dog model. Ten beagle dogs were randomized into two groups: five were given 2 mg/kg/day IM injections of prednisone to induce steroid hepatopathy and five served as controls. Histology showed vacuolization in most hepatocytes of treated animals on the third day of treatment, and larger, midzonally distributed vacuoles from day 7 on. An increase in both ultrasonic attenuation and backscatter was observed in treated dogs during in vivo measurements. Pooled data from the two groups suggest that attenuation elevations precede backscatter changes. Attenuation was significantly higher in the treated animals than in the controls by day 7. Both attenuation and backscatter were significantly higher in livers of treated than untreated dogs when measured by direct application of the transducer on the liver following euthanasia. We conclude that attenuation and backscatter coefficients can detect early changes in the liver associated with steroid hepatopathy. This may be a useful model to investigate detection of diffuse liver disease with ultrasound tissue characterization.

Measurement of acoustic backscatter and attenuation in the liver of dogs with experimentally induced steroid hepatopathy

OBJECTIVE

To determine the usefulness of a new method of measuring acoustic backscatter and attenuation in the liver of dogs with experimental steroid-induced hepatopathy.

ANIMALS

10 clinically normal dogs.

PROCEDURE

Steroid hepatopathy was induced by daily injections of prednisone (2 mg/kg of body weight, IM). Dogs were evaluated histologically and were sonographically imaged on days 0, 3, 7, 10, and 14. Acoustic backscatter and attenuation were measured from in vivo images of dogs, using a video signal method, and compared with results obtained from analysis of the unprocessed radio frequency signal.

RESULTS

Histologic evaluation revealed midzonal, predominantly water-filled vacuoles in hepatocytes by day 7, which persisted for the remainder of the study and significantly (P = 0.0001) increased liver weight on day 14. Attenuation and backscatter increased during the experimental period. Mean effective attenuation difference was higher (P = 0.015) in the liver imaged through a left paraxyphoid window in experimental dogs by day 3. Significantly (P < 0.05) greater attenuation persisted in the liver of experimental dogs throughout the experimental period. Mean backscatter ratio was significantly increased (P = 0.02) by day 10. Uncorrected pixel intensity of the liver in 2 experimental dogs was approximately equal to that of the spleen on day 10 and greater than that of the spleen on day 14.

CONCLUSION

Administration of prednisone to dogs results in increased acoustic backscatter and attenuation in the liver.

CLINICAL RELEVANCE

The video signal method is a sensitive technique for detecting subtle acoustic changes in the liver of dogs.

Clinical applications of radiography and ancillary imaging

Radiography will remain the most popular imaging modality in the near future for many reasons. It is economical, portable, and familiar to large animal practitioners. Contrast radiography allows evaluation of vascular and tract lesions. Other modalities may offer various advantages. Diagnostic sonography has the advantage of being able to evaluate soft tissue structure damage, fluid pockets, and lucent foreign bodies. Xeroradiography and CR use conventional, high-powered x-ray units for the production of images on nontraditional ionized film plate-cassette systems. Both systems provide superior bone-soft tissue contrast, by virtue of edge enhancement, than does conventional radiography. CT and MR imaging provide cross-sectional imaging of bones and adjacent structures, avoiding structures that may be superimposed on the area of interest with conventional radiography. The major limitation is the demand for a custom-engineered couch able to withstand the weight of an adult bovine. Scintigraphy provides important functional information for the clinical evaluation of orthopedic disease. It may be the most useful imaging tool to localize the cause of lameness.

Radiographic findings in cats with intranasal neoplasia or chronic rhinitis: 29 cases (1982-1988)

OBJECTIVE

To compare radiographic findings and determine useful criteria to differentiate between intranasal neoplasia and chronic rhinitis in cats.

DESIGN

Retrospective study.

ANIMALS

Cats with chronic nasal disease caused by neoplasia (n = 18) or by chronic rhinitis (n = 11).

PROCEDURE

Radiographs were reviewed by 3 radiologists, followed by group review. Diagnosis was determined by intranasal biopsy or necropsy, and specimens were reviewed by a pathologist to confirm cause and histologic diagnosis.

RESULTS

Lymphosarcoma was the most common (n = 5) of the 6 histopathologic types in the neoplasia group. Cats in the neoplasia and chronic rhinitis groups had a high prevalence of aggressive radiographic lesions. Prevalence of a facial mass in cats with neoplasia (8/18) versus in those with chronic rhinitis (4/11) and of deviation (9/18 vs 6/11, respectively) or lysis (12/18 vs 7/11) of the nasal septum was similar. However, significantly (P = 0.02) more cats with neoplasia than with chronic rhinitis (13/16 vs 3/7, respectively) had unilateral turbinate destruction/lysis. Additionally, unilateral lateral bone erosion and loss of teeth associated with adjacent intranasal disease were more prevalent in cats with neoplasia (7/8 and 5/18, respectively) than in cats with chronic rhinitis (1/3 and 0/11, respectively).

CLINICAL IMPLICATIONS

Features that may assist in radiographic diagnosis of neoplasia include the appearance of unilateral aggressive lesions, such as lysis of lateral bones, nasal turbinate destruction, and loss of teeth. Bilaterally symmetric lesions are more suggestive of chronic rhinitis than of neoplasia.

Low numbers of CSF blasts at diagnosis do not predict for the development of CNS leukemia in children with intermediate-risk acute lymphoblastic leukemia: a Childrens Cancer Group report

PURPOSE

This study was designed to evaluate the effect on CNS relapse (CNSR) and overall relapse rates of blast cells in the CSF containing < or = 5 cells/microL at the time of diagnosis of intermediate-risk acute lymphoblastic leukemia (ALL) in children entered onto a large randomized multicenter prospective therapeutic trial (Childrens Cancer Group [CCG]-105).

PATIENTS AND METHODS

We studied outcome in terms of CNSR and event-free survival (EFS) in 1,544 patients who successfully completed remission-induction therapy and had been randomized to one of four systemic chemotherapy regimens and to one of two CNS prophylaxis regimens. We compared outcome between 1,450 patients who had varying degrees of pleocytosis but no blasts in the CSF at diagnosis (blast-negative group) with 94 who had blasts detected in the CSF after cytocentrifugation but had a total CSF WBC count of < or = 5/microL (blast-positive group).

RESULTS

No statistically significant differences in overall CNSR or EFS rates were observed between the two groups and no differences were found when analyzed according to age or WBC count at diagnosis, sex, or type of CNS prophylaxis (intrathecal [IT] methotrexate [MTX] alone v IT MTX plus 18 Gy cranial irradiation [CXRT]).

CONCLUSION

In intermediate-risk ALL, there was no significant difference in CNSR and systemic relapse rates after standard presymptomatic CNS therapy between patients with a CSF WBC count < or = 5/microL and those without identifiable blasts in the CSF. These findings suggest that certain approaches to therapy, such as that used in this study, may eliminate the need for any additional special treatment directed at this subset of patients with CSF blasts.

Blasts in CSF with a normal cell count do not justify alteration of therapy for acute lymphoblastic leukemia in remission: a Childrens Cancer Group study

PURPOSE

The Childrens Cancer Group (CCG) requires both a CSF WBC count of more than five cells per microliter and demonstration of blast cells in the cytocentrifuge specimen to support a diagnosis of CNS relapse. We reviewed the CSF examinations of patients with intermediate-risk acute lymphoblastic leukemia (ALL) to determine the clinical significance of blast cells reported in the cytocentrifuge when the total CSF cell count was normal.

PATIENTS AND METHODS

Children treated on CCG-105 for ALL had CSF examinations every 12 weeks during maintenance therapy. The outcome of children who had a positive CSF cytocentrifuge examination without an elevated CSF WBC count was compared with that of children who did not have any CSF blast cells observed.

RESULTS

Sixty-four patients had 81 CSF examinations with blast cells and a normal cell count. By Cox life-table regression analysis, patients with blasts had a different disease-free survival (DFS) distribution, with relapses tending to occur earlier (P = .008). However, the DFS for these patients was 63% +/- 9.6% at 5 years from the time of the abnormal cytocentrifuge result as compared with 69% +/- 1.5% for 1,490 children who did not have blasts in their CSF. This difference is not significant.

CONCLUSION

Blast cells were infrequently identified in cytocentrifuge preparations of CSF when the cell count was normal. The majority of patients in whom such an event was observed have not experienced a subsequent relapse as measured by life-table analysis at 5 years. The data do not justify changing or augmenting therapy based on cytocentrifuge results alone.

Prevention of CNS disease in intermediate-risk acute lymphoblastic leukemia: comparison of cranial radiation and intrathecal methotrexate and the importance of systemic therapy: a Childrens Cancer Group report

PURPOSE

This study (Childrens Cancer Group [CCG]-105) was designed in part to determine in a prospective randomized trial whether intrathecal methotrexate (IT MTX) administered during induction, consolidation, and maintenance could provide protection from CNS relapse equivalent to that provided by cranial radiation (CXRT) in children with acute lymphoblastic leukemia (ALL) and intermediate-risk features.

PATIENTS AND METHODS

We randomized 1,388 children with intermediate-risk ALL to the two CNS regimens. They received either IT MTX at intervals throughout their course of therapy or CXRT (18 Gy) during consolidation with IT MTX during induction, consolidation, and delayed intensification. Systemic therapy was randomized to one of four treatment regimens derived from a regimen used by CCG in recent studies for this patient population and three more intensive regimens based on the Berlin-Frankfurt-Munster trials.

RESULTS

Life-table estimates at 7 years show a 93% and 91% CNS relapse-free survival rate for the CXRT and IT MTX groups, respectively. The corresponding event-free survival (EFS) rates are 68% and 64%. The differences are not significant. Patients who received more intensive systemic therapy had a 94% CNS relapse-free survival rate on either CXRT or IT MTX, while patients who received standard systemic therapy had 90% and 80% rates for CXRT and IT MTX, respectively (P < .0001). Patients less than 10 years of age who received CXRT or IT MTX had 72% and 71% EFS rates if they received more intensive systemic therapy. Patients 10 years or older who received CXRT had an improved EFS (61% v 53%) with a more intensive systemic program. This was primarily due to fewer bone marrow relapses (P = .04).

CONCLUSIONS

IT MTX during induction, consolidation, and maintenance provides protection from CNS relapse in patients with intermediate-risk ALL equivalent to that provided by CXRT if more intensive systemic therapy is given. The CNS relapse rate with either CXRT or IT MTX is in part dependent on the associated systemic therapy. For intermediate-risk patients less than 10 years of age, IT MTX with an intensified systemic regimen provided CNS prophylaxis comparable to that provided by CXRT, whereas older patients had fewer systemic relapses if they received CXRT.

Improved outcome with delayed intensification for children with acute lymphoblastic leukemia and intermediate presenting features: a Childrens Cancer Group phase III trial

PURPOSE

The Berlin-Frankfurt-Munster (BFM) 76/79 trial of acute lymphoblastic leukemia (ALL) in children produced impressive disease-free survival (DFS) rates with a protocol that began with 8 weeks of intensive therapy, followed by 8 weeks of maintenance therapy, and then another 6 weeks of intensive treatment. The current study was conducted to determine the relative contributions of each of these periods of intense therapy on the DFS rates of ALL patients with intermediate presenting features. In addition, due to concerns regarding the toxicity of CNS irradiation, we compared cranial irradiation (CXRT) with intrathecal methotrexate (IT MTX) administered during induction and consolidation to IT MTX during all phases of the treatment program.

PATIENTS AND METHODS

Between May 1983 and April 1989, more than 1,600 children with ALL and intermediate presenting features, as defined by the Childrens Cancer Group (CCG), were entered into a randomized trial that tested four systemic therapy regimens and two CNS programs.

RESULTS

The results with a median follow-up of 57 months show that systemic regimens with a delayed intensification (Delint) phase of therapy had a 5-year event-free survival (EFS) rate of 73% compared with the control regimen EFS rate of 61% (p = .006). For children less than 10 years of age, standard three-drug induction and Delint produced a 77% 5-year EFS. IT MTX during all phases of therapy provided CNS protection comparable to the CXRT regimen in children less than 10 years of age. Children 10 years of age or older appear to have a better EFS rate with intensive induction, Delint, and CXRT.

CONCLUSION

Delint improves the EFS rate of children with ALL and intermediate presenting features. Maintenance IT MTX can be safely substituted for CXRT for presymptomatic CNS therapy in children with intermediate-risk characteristics less than 10 years of age.

Pathological and radiographical features of multicentric malignant fibrous histiocytoma in two dogs

Widespread organ distribution of malignant fibrous histiocytoma, including osseous involvement, was demonstrated in two dogs. Both cases had a storiform-pleomorphic pattern histologically and immunohistochemical stains were used to differentiate this from other types of neoplasms with the same histological pattern. Radiographically the lesions were predominantly lytic in the metaphysis of long bones, although periosteal proliferation and axial skeletal involvement were seen in one dog.

CNS prophylaxis of childhood leukemia: what are the long-term neurological, neuropsychological, and behavioral effects?

Current medical treatments for childhood acute lymphoblastic leukemia (ALL) have improved the outlook to where more than 50% can be expected to survive five years or more. The use of CNS prophylaxis has contributed in a significant way to these improved survival statistics by reducing the likelihood of CNS relapses. The literature relating to the potential adverse psychological consequences of CNS prophylaxis, which include cranial radiation therapy (CRT), is reviewed and analyzed. The majority of published papers of children in first remission report that CNS prophylaxis, which include both CRT and intrathecal methotrexate, results in a variety of learning problems in many children who were younger than age 5 when treated. The available literature on the social, emotional, and educational sequelae of childhood ALL is also reviewed.

Efficacy and toxicity of 12 courses of ABVD chemotherapy followed by low-dose regional radiation in advanced Hodgkin's disease in children: a report from the Children's Cancer Study Group

Sixty-four patients aged 2 to 18 years with advanced-stage Hodgkin's disease (HD) were treated on a Children's Cancer Study Group (CCSG) pilot toxicity study (521-P). Therapy consisted of 12 courses of Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), bleomycin, vinblastine, and dacarbazine (ABVD), followed by low-dose (2,100 cGy in 12 fractions) regional irradiation (RT). All patients were monitored for toxicity with particular attention to the pulmonary system. Six patients (9%) developed grade 3 or 4 pulmonary toxicity. Three had grade 3 toxicity based solely on changes in carbon monoxide diffusing capacity (DLCO) and remained well for more than 3 years after diagnosis. There was one fatality among the three symptomatic cases. In five cases, toxicity occurred prior to RT. One occurred after seven courses of ABVD, one after nine courses, and three after 10 courses. In one of these five cases, ABVD was stopped. The patient was given nitrogen mustard (mechlorethamine), vincristine, prednisone, and procarbazine (MOPP). This patient subsequently developed recurrence of HD and died of overwhelming sepsis. The other four continued on study and completed their chemotherapy. Three patients had no further bleomycin, and one continued bleomycin at 50% of the assigned dose. They all received mantle RT following chemotherapy, one with a boost dose to the mediastinum to 3,800 cGy and one with added RT to both lungs (1,050 cGy). In the sixth case of pulmonary toxicity, symptoms were first noticed 2 weeks after mantle RT to 3,500 cGy. This patient died of progressive respiratory failure. The event-free survival (EFS) and overall survival is 87% at 3 years. These early results indicate that this therapy is effective in advanced HD in children but has a 9% incidence of acute pulmonary toxicity.

Retained caseous yolk sac in a Burmese python (Python molurus bivittatus)

Retained yolk sacs are common in the domestic chicken and account for considerable morbidity and mortality during late embryonic development and within the first 10 days of life. What is believed to be the first recorded instance of a retained caseous yolk sac and its successful surgical removal from a Burmese python (Python molurus bivittatus) is reported. The snake experienced no post-operative complications and continues to be well 16 mo following surgery.

Biphenotypic leukemic lymphocyte precursors in CD2+CD19+ acute lymphoblastic leukemia and their putative normal counterparts in human fetal hematopoietic tissues

During detailed immunophenotypic analyses of marrow blasts from 336 acute lymphoblastic leukemia (ALL) patients, a very small percentage of cases reactive with B-cell-directed as well as T-cell-directed monoclonal antibodies (MoAbs) were identified. Five ALL cases were biphenotypic since they coexpressed CD2 (Tp50) and CD19 (Bp95) antigens at the single-cell level. The composite immunophenotype of these biphenotypic ALL cases was [TdT+HLA-ABC+CD2+CD3-CD10+CD13-CD14-CD16-CD19+CD20+ ++-CD21-CD33-CD34+Bgp95-C mu- slg-]. Low-molecular-weight B-cell growth factor (LMW-BCGF), recombinant interleukin-2 (rIL-2), and rIL-3 stimulated the proliferative activity of biphenotypic leukemic lymphocyte precursors without inducing differentiation. In the presence of the phorbol ester TPA, leukemic blasts from two cases differentiated along the B precursor pathway to the [CD2-CD10+CD19+CD20+C mu+slg-] pre-B cell stage. Biphenotypic ALL cases did not share a common configuration and gene rearrangement pattern of the immunoglobulin heavy chain genes or T-cell receptor (TCR) genes. Three cases had rearranged C mu genes but germline TCR genes, one case showed rearrangement of both C mu and TCR genes, and the remaining case had rearranged TCR genes but germline C mu genes. All five patients attained prompt remission after standard induction chemotherapy. Three to four years after initial diagnosis, four patients are now off chemotherapy and remain alive in their first remission. One patient relapsed at 3 years, 7 months, but promptly achieved complete remission after reinduction chemotherapy and remains in second remission off chemotherapy greater than 3 years after her reinduction therapy. With two-color immunofluorescence staining techniques and multiparameter flow cytometric analyses, we identified a small population of CD2+CD19+ lymphoid cells in fetal livers (FLs) and fetal bone marrows (FBMs), which may represent the putative normal counterparts of biphenotypic ALL blasts. A CD2+CD19+ normal biphenotypic lymphoid precursor cell line, designated FL 8.2 CD2+, was established from an FL of 8-weeks of gestational age by Epstein-Barr virus (EBV)-induced blastoid transformation. The composite immunophenotype of FL 8.2 CD2+ cell line was [TdT+HLA-ABC+HLA-DR+ CD2+CD5-CD7-CD10+/-CD13-CD19+CD20-CD21+ CD22+CD33-CD34+/-Bgp95-CDw40+C mu-slgD-slgM-]. FL 8.2 CD2+ cells showed germline patterns of immunoglobulin heavy-chain joining region, heavy-chain constant region, kappa light-chain constant region genes, and TCR beta-chain genes. Cross-linking of CD2 as well as CD19 antigens on FL 8.2 CD2+ cells caused an increase of intracellular ionized calcium.(ABSTRACT TRUNCATED AT 400 WORDS)

Idiopathic thrombocytopenic purpura in children

Idiopathic thrombocytopenic purpura is a disorder characterized by antibody-mediated platelet destruction. Other than thrombocytopenia and its consequences, the physical and laboratory examination of the child with ITP is normal. The prognosis in children is excellent; 90 percent will recover spontaneously within one year. Serious hemorrhage is uncommon and conservative management is appropriate. Aspirin and potential trauma should be avoided. Transfusions are rarely necessary or helpful. Corticosteroids may cause a more rapid rise in the platelet count but do not influence the long-term prognosis.

Thrombocytosis in children with Hemophilus influenzae meningitis

A retrospective study of thrombocytosis in children with Hemophilus influenzae meningitis was performed. Forty-five percent of patients had a platelet count greater than 500 X 10(9)/l during hospitalization. The mean platelet count was 284 X 10(9)/l on admission, and gradually increased to 648 X 10(9)/l on day 11 of hospitalization. These results document that thrombocytosis is common among children with H. influenzae meningitis and suggest that it is probably a recovery phenomenon.

Dose response analysis of pediatric neuroblastoma to megavoltage radiation

Children with neuroblastoma treated in Salt Lake City from 1966 through 1982 were analyzed in an attempt to develop guidelines for external beam radiation. Particular attention was addressed to time-dose relationships in those patients with residual disease post-resection (Stages II and III). Altogether, 76 patients were analyzed and survival rates were: Stage I--100%; Stage II--84%; Stage III--69.2%; Stage IV--14.3%; Stage IV-S--71.4%. Survival rates were correspondingly better in younger children and in infants. Indications for postoperative radiation therapy in this population were: unresectable or gross remaining tumor; residual tumor in neural foramina; tumor spill during surgery; positive regional lymph nodes or positive surgical margins. Local control was achieved in a majority of patients undergoing surgery and radiation for limited disease. In children younger than 1 year of age, no local failures were observed at doses above 1200 rad. In children between 1-2 years of age, no local failures were observed with doses as low as 1440 rad. In children older than 3 years, local failures were observed up to 4500 rad.

Poor prognosis for mucin-producing Wilms' tumor

This report describes two cousins with Wilms' tumor and mucin detected in the sera with rapidly fatal courses. A review of the literature reveals five additional reported cases of Wilms' tumor where mucin was observed in the sera. The patients in this report are similar to those previously reported in that all had metastatic disease at diagnosis, and four of five died within one year of diagnosis. Both the extent of disease at diagnosis at the poor response to therapy in these two cases, and those from the literature suggest that evidence of mucin production may indicate poor prognosis in Wilms' tumor. In addition, evidence is reviewed that mucin itself may contribute to a rapid tumor growth and metastases. The genetics of Wilms' tumor and familial nature of these cases is also discussed.

Relative anemia and iron deficiency in cystic fibrosis

Significant alterations in hemotologic function in cystic fibrosis are suggested by the observation that polycythemia is uncommon, even among cyanotic patients. To elucidate those factors that influence hematologic equilibrium, 39 stable patients with cystic fibrosis were evaluated with regard to hemoglobin, hematocrit, RBC indices, reticulocyte count, serum iron and total iron binding capacity, serum ferritin, vitamin E, and carboxyhemoglobin levels. Hemoglobin concentrations were below the 50th percentile for age in 90% of the patients, including the 23% who were cyanotic. Serum ferritin levels were below the mean for age in 85% and below 12 ng/mL in 33% of patients. Vitamin E levels were less than 5 micrograms/dL in 33%, indicating deficiency. Carboxyhemoglobin values were elevated in 64% of the patients. These data indicate that relative anemia is common in cystic fibrosis and suggest that iron and vitamin E deficiency may contribute to that anemia. Twenty-two patients with cystic fibrosis were then given 2 weeks of oral iron therapy followed by two to three additional weeks of iron and vitamin E. This therapeutic trial resulted in an increase in mean hemoglobin concentration from 13.87 to 14.50 g/dL (P less than 0.01) associated with a significant increase in levels of serum ferritin (P less than 0.001). The increase in hemoglobin occurred primarily during the second 2 weeks when patients were receiving both iron and vitamin E. However, we were unable to document evidence of increased hemolysis when patients were receiving iron therapy alone. This response to oral iron therapy is confirmation that iron deficiency contributes to the failure of some patients with cystic fibrosis to compensate hemotologically for hypoxia.

Mechanisms of inactivation of poliovirus by chlorine dioxide and iodine

Chlorine dioxide and iodine inactivated poliovirus more efficiently at pH 10.0 than at pH 6.0. Sedimentation analyses of viruses inactivated by chlorine dioxide and iodine at pH 10.9 showed that viral RNA separated from the capsids, resulting in the conversion of virions from 156S structures to 80S particles. The RNAs release from both chlorine dioxide- and iodine-inactivated viruses cosedimented with intact 35S viral RNA. Both chlorine dioxide and iodine reacted with the capsid proteins of poliovirus and changed the pI from pH 7.0 to pH 5.8. However, the mechanisms of inactivation of poliovirus by chlorine dioxide and iodine were found to differ. Iodine inactivated viruses by impairing their ability to adsorb to HeLa cells, whereas chlorine dioxide-inactivated viruses showed a reduced incorporation of [14C]uridine into new viral RNA. We concluded, then, that chlorine dioxide inactivated poliovirus by reacting with the viral RNA and impairing the ability of the viral genome to act as a template for RNA synthesis.

Quality of Meat from Cattle Fed Sewage Solids 1

Beef heifers in a feedlot were fed an experimental (E) diet containing gamma-irradiated ("pasteurized") dried sewage solids as 20% of the diet. Similar heifers received a conventional diet and served as controls (C). Four heifers from each group were slaughtered at the 68th day of the feeding program. Carcasses from E were smaller than from C (202 versus 245 kg), had less fat thickness (.76 versus 1.0 cm) and less internal fat (2.5 versus 2.9%). Steaks, roasts and ground beef (composite of all trimmings) were displayed for 3 d in a refrigerated (2-4°C) meat case. Ground meat from E was superior to C in lean color and overall visual acceptance; but the reverse was true for steaks and roasts (P<.05). Steaks and roasts from C were evaluated slightly higher than E in firmness of lean, resulting from more subcutaneous carcass fat of C. Microbial contamination of carcasses was assayed by cultures from swabs taken from the diaphragm muscle and the 12/13th rib area of hanging sides (at slaughter and days 2 and 7 postmortem) and from swabs and core samples of product at day 0 and days 3 and 17 postmortem. Colony counts from core samples taken from bulk ground beef (C) and soaked in peptone water averaged 8.5 × 10⁴ for day 0 and 7.5 × 10⁶ for day 3 samples, while samples from E carcasses averaged 3.8 × 10⁴ (day 0) and 4.1 × 10⁷ (day 3). Colony counts from surface swabs of beef patties averaged 4.6 × 10⁴ (day 0) and 5. 7 × 10⁶ (day 3) for C and 6.5 × 10⁴ (day 0) and 9.4 × 10⁶ (day 3) for E. Microbial counts of the product surveyed in this study did not differ (P>.05) due to diets (E vs. C). Livers and kidneys from cattle fed the E diet had higher levels (P<.05) of Fe and Pb than those from cattle receiving the C diet.