Oxygen distribution in squamous cell carcinoma metastases and its relationship to outcome of radiation therapy.

Oxygen distribution was measured in 31 fixed lymph node metastases (mean diameter 4.4 cm +/- 0.8 cm) from squamous cell carcinoma of the head and neck by passing a needle electrode through each tumor under CT guidance. Thirteen tumors had uniform oxygen distribution with all measurements under 10 mm Hg. Six tumors had uniform oxygen distribution with all measurements above 10 mm Hg, and twelve tumors had variable oxygen distribution with measurements higher in the periphery than in the center. Response to radiation therapy was judged by changes in tumor volume 90 days following completion of therapy compared to pre-therapy volume. Eighteen tumors were considered complete responders (CR); eleven, non-responders (NR); two, partial responders (PR). No statistically significant difference in radiation dose or tumor size was seen in the PR and CR groups. Mean pO2 was 20.6 (+/- 4.4) mm Hg in the CR group and 4.7 (+/- 3.0) mm Hg in the NR group (p less than 0.001). Normalized pO2 content defined as the total tumor oxygen content normalized by dividing by the volume was 37.4 (+/- 8.2) mm Hg in the CR group and 8.2 (+/- 5.1) mm Hg in the NR group (p less than 0.001). The volume and oxygen levels of each tumor were tabulated and analyzed. Twelve tumors had greater than 26% of their volume containing a pO2 less than 8 mm Hg. Eleven of these were NR and one PR. Nineteen tumors had less than 26% of their volume containing a pO2 less than 8 mm Hg. Eighteen were CR and one PR (p less than 0.001). These data suggest that oxygen plays a significant role in human tumor response to radiation therapy. Oxygen measurements appear to allow separation of subgroups of patients with a poor prognosis who would most benefit from maneuvers to circumvent the hypoxic effect.

Bony landmarks are not an adequate substitute for lymphangiography in defining pelvic lymph node location for the treatment of cervical cancer with radiotherapy.

PURPOSE: Curative radiotherapy (RT) for carcinoma of the cervix requires adequate irradiation of regional lymph node groups. The best nonsurgical method of defining lymph node anatomy in the pelvis remains the lymphangiogram (LAG). This study was designed to determine if bony landmarks could accurately substitute for LAG as a means of determining lymph node position for the purpose of pelvic RT treatment planning. METHODS AND MATERIALS: The post-LAG simulation films of 22 patients treated at the Fox Chase Cancer Center for cervical cancer were examined. On anterior/posterior (A/P) simulation films, the distance of lymph nodes was determined from the top, middle, and bottom of the sacroiliac joint, and at the pelvic rim, 1 and 2 cm above the acetabulum. On lateral (LAT) simulation films, lymph node position was measured at points 0, 4, and 8 cm along a line from the bottom of L5 to the anterior aspect of the pubic symphysis. Positive values represent lateral and anterior distances relative to the reference point on A/P and LAT films, respectively. Negative values represent distances in the opposite direction. The adequacy of standard pelvic fields as defined by the Gynecologic Oncology Group (GOG) (A/P: 1.5 cm margin on the pelvic rim; LAT field edge is a vertical line anterior to the pubic symphysis) was also examined. Data are expressed as the mean +/- two standard deviations, (i.e. 95% confidence level). RESULTS: On A/P simulation films, the distance of visualized lymph nodes had mean values of -1.6 +/- 1.7 cm (range -4.1 to -0.4 cm), -1.3 +/- 1.5 cm (range -3.4 to 0.0 cm), and 1.2 +/- 1.8 cm (range -1.0 to 2.6 cm) from the sacro-iliac (SI) joint at the superior, middle, and inferior points, respectively. The mean distance of the nodes from the pelvic rim at points 1 and 2 cm above the acetabulum was 0.3 +/- 1.2 cm (range -0.6 to 1.8 cm) and 0.2 +/- 1.8 cm (range -1.6 to 2.1 cm), respectively. On LAT simulation films, the distance of lymph nodes from points 0, 4, and 8 cm from the previously described reference line had mean values of 2.0 +/- 1.0 cm (range 1.3 to 3.0 cm), 0.9 +/- 3.9 cm (range -1.9 to 5.1 cm), and 1.8 +/- 2.1 cm (range -0.8 to 3.5 cm), respectively. Ten of 22 (45%) patients would have had inadequate nodal irradiation if their fields had been designed according to standard GOG parameters. In all cases, these incompletely irradiated lymph nodes were from the lowest of the lateral external iliac group. CONCLUSION: Great variability in pelvic lymph node location is demonstrated when LAG is used to directly visualize their location. Bony structures are inaccurate landmarks for pelvic lymph node position. The GOG standard pelvic fields are not consistently adequate to cover all lateral external iliac lymph nodes, although the clinical significance of this subgroup of lymph nodes is not known. At this time, LAG remains the ideal radiographic modality to define anatomic location of regional lymph nodes for pelvic RT treatment planning. The clinical importance of the most lateral group of external iliac lymph nodes in various stages of cervical cancer represents a potential area of future research.

Coronary thrombosis in a patient with May-Hegglin anomaly.

May-Hegglin anomaly (MHA) is a rare hereditary condition that is characterized by cytoplasmic inclusions in leukocytes and giant platelets. Many patients have some degree of thrombocytopenia. Most individuals with MHA are asymptomatic, but 25-43% of patients previously reported have had a hemorrhagic tendency. The authors describe a patient with MHA who had no history of hemorrhage but who developed complete coronary thrombosis after attempted angioplasty despite an apparent platelet count of 24,000 per mm3. Laboratory investigations revealed a normal bleeding time, normal platelet aggregation, and an increase in the size of approximately two-thirds of the platelets. The calculated platelet mass was near normal, which probably explains the thrombosis despite a decrease in platelet numbers. The authors conclude that in some patients with MHA platelets are functionally active both in vivo and in vitro.

Single donor, HL-A matched platelet transfusions for thrombocytopenic patients undergoing surgery.

Thrombocytopenic patients, who displayed hemostatic disorders and had been previously sensitized by repeated blood transfusions and/or pregnancies, were supported for surgical procedures by platelet transfusions obtained from a single ABO and HL-A matched donor by the use of continuous collection centrifugation. Because of the low incidence of HL-A identical donors, compatibility was assessed by known serological cross-reactivity of the HL-A determinants. In three cases repeated platelet transfusions had excellent in vivo survival, and sensitization could not be detected by a battery of immunological assays. In one case there was immune sensitization and refractoriness to repeated platelet transfusion, as documented by accelerated in vivo destruction of donor and third-party platelets bearing the disparate factor HL-A8. Although serologic tests for lymphocytotoxic and leukoagglutinating antibodies were negative, the patient displayed cellular immunity in leukocyte aggregation and cell-mediated plateletolysis tests. The single donor, continuous collection technique appears to have the technical advantage of rapid, efficient collection and the immunological benefit of a restricted spectrum of allosensitization.

A model for an outpatient imaging center.

U.S. federally imposed efforts to regulate joint venturing are a result of certain physician strategies to circumvent anti-kickback statutes by investing in clinics, labs, and facilities for self-referral. This article addresses the ethical debate on physician ownership, MRI as an evolving modality, the 1989 Ethics in Patient Referrals Act and the subsequently released "safe harbors," and finally, describes an existing model for physician/hospital ownership in an outpatient MRI facility.

Keratitis on exposure to dimethyl phosphorochloridothionate (dmpct).

Six cases of exposure to Dimethy Phosphorochloridothionate (DMPCT) are reported. All patients suffered cornel injuries. Characteristically the corneal lesions (punctate keratitis) became apparent after an interval of at least eight hours. With proper treatment all patients recovered completely with no impairment of visual acuity.

Percutaneous catheter drainage for malignant pericardial effusion.

Ultrasound (US)-guided and fluoroscopically guided pericardial catheter placement was performed in 12 patients with known underlying malignancy who had clinical and radiographic evidence of a significant pericardial effusion. US guidance facilitated placement of a 22-gauge needle by means of a subxyphoid or transthoracic approach. The tract was subsequently dilated over a wire under fluoroscopic guidance with placement of either an 8.5- or 10-F catheter. This technique successfully established pericardial drainage in all patients with excellent symptomatic relief. Cytologic findings were positive for malignancy in 10 of the 12 patients. Radiologically guided pericardiocentesis allowed safe, rapid stabilization of the condition of patients with symptoms from pericardial effusion. This resulted in excellent palliation in patients with terminal disease and improvement in the clinical status of other patients so that additional therapies, such as sclerosis with tetracycline or surgical placement of a pericardial window, could be performed on an elective basis.

Diagnosis of osteomyelitis by MR imaging.

Bone scans are highly sensitive for the diagnosis of acute osteomyelitis, but the difficulty of separating bone-marrow processes from soft-tissue disease limits the specificity and accuracy. A diagnostic technique capable of distinguishing bone-marrow processes from soft-tissue disease would improve the diagnostic accuracy of osteomyelitis. To evaluate the use of MR in the diagnosis of osteomyelitis, MR examinations were performed in 35 patients with suspected acute osteomyelitis. Twelve of these were proved to have osteomyelitis either by surgery (nine patients) or by clinical follow-up (three patients). In the other 23, osteomyelitis was excluded by surgery (12 patients) or by the clinical course (11 patients). Evidence of osteomyelitis on MR consisted of abnormalities of the bone marrow with decreased signal intensity on the T1-weighted images and increased signal intensity on the T2-weighted or short-T1 inversion recovery (STIR) images. MR and bone scintigraphy were interpreted by two radiologists who were given no clinical information other than to rule out osteomyelitis. The sensitivities of MR and static bone scan were 100% for bone-marrow abnormality. Because bone-marrow abnormality in osteomyelitis associated with healing fractures was incorrectly diagnosed by MR (one case) and bone scintigraphy (two cases), the sensitivities of MR and scintigraphy for the diagnosis of osteomyelitis were 92% and 82%, respectively. The specificities of MR and scintigraphy were 96% and 65%, respectively (p less than .05). The overall accuracy for the diagnosis of osteomyelitis was 94% for MR and 71% for bone scan (p less than .05). Because of its ability to separate soft-tissue disease from underlying bone marrow, MR may be used to evaluate patients with positive bone scintigraphy to improve the specificity and accuracy of diagnosis for osteomyelitis.

Case report 723. Popliteal artery aneurysm.

An unusually large, noncalcified popliteal artery aneurysm causing cortical erosion was erroneously diagnosed as a soft-tissue sarcoma. The case stresses the importance of excluding a vascular cause of a mass whenever biopsy is considered. We review the clinical and radiological features of popliteal artery aneurysm and describe the appearance of the aneurysm on MR.

Sonographically guided paracentesis for palliation of symptomatic malignant ascites.

The technique, results, and complications of 109 consecutive sonographically guided therapeutic paracenteses performed on 43 patients with malignant ascites are summarized. A 5.5-French Sacks One-Step Catheter was used in all cases but five in which tissue resistance prohibited passage of the catheter through the abdominal wall. The procedure was performed on an inpatient basis 70 times and in an outpatient setting 39 times. Colonic, ovarian, and breast carcinomas accounted for over 50% of the tumors resulting in malignant fluid collections. Three complications (hypotension, 2.6%) were directly related to the procedure; two of them were fatal (1.6%). The amount of ascitic fluid drained within the first 24 hr averaged 3.5 l at rates of 100-150 ml/sec. Ninety-five procedures (87%, in 39 patients) resulted in improvement of symptoms after drainage as manifested by decreased pain from abdominal distention, alleviation of nausea, improved appetite, or decreased dyspnea. The duration of symptomatic relief ranged from 4 days to 45 days (mean, 10.4 days). Sonographically guided paracentesis is an effective procedure that can be performed for short-term relief of symptoms caused by malignant ascites.

Atraumatic method of intraoperative retrograde transhepatic biliary stent insertion.

A significant risk of hepatic injury remains using reported methods of intraoperative retrograde transhepatic stenting (IRTS). Our hypothesis was that we could minimize this risk by: (1) using a pliable sheath to create a stent tract that follows the curve of the biliary tree, (2) decreasing the stent diameter, and (3) avoiding the hepatic hilum. We evaluated the safety of a novel technique of intraoperative stenting employing these three concepts. Twenty-four patients underwent IRTS between 1992 and 1995 at our institution after potentially curative resection (one bypass). Malignant disease was present in 22 of 24 patients. Bile ducts were normal caliber in all patients. There was no operative mortality and 38% operative morbidity, all readily treated. All complications were due to stent dislodgment. There were no deaths. This novel atraumatic method of IRTS has acceptable morbidity and mortality. Complications due to stent insertion are minimal. The technique compares favorably with previous methods of IRTS and offers a viable alternative to the surgeon when a transhepatic stent is required. Anchoring the stent securely to the skin is essential to prevent catheter dislodgement.

Radiologically guided balloon dilation of gastrointestinal strictures. Part II. Results of long-term follow-up.

Balloon dilation catheters were used to treat 94 gastrointestinal strictures in 92 patients over a 6-year period. Long-term follow-up data were obtained for 80 of these patients, with a mean follow-up period of 389 days. Overall, of the patients who underwent a successful dilation procedure, 83% remained symptom free after 1 year, and 69% after 2 years. The location of the stricture did not significantly influence the long-term outcome, nor did procedure characteristics, aside from primary technical failure. Both patients with malignant strictures and those whose strictures were associated with an anastomosis were more likely than other patients to have recurrent symptoms.

Radiologically guided balloon dilation of gastrointestinal strictures. Part I. Technique and factors influencing procedural success.

Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.

Retained anchoring suture after removal of a Cope-loop drainage catheter: use of the retract-and-cut method.

A method is described for managing retention of the anchoring suture within the tract after a Cope-loop drainage catheter has been removed. In the authors' experience, the overwhelming majority of such strings can be extracted by sliding a dilator over the suture and using gentle manipulation at the site of adherence. However, in 12 patients, this technique was not successful. In these patients, the retract-and-cut method was used: The suture is pulled taut and cut at the surface, allowing it to retract into the tract. This provided a safe and simple solution for this complication.

CT staging of esophageal carcinoma in patients treated by primary radiation therapy and chemotherapy.

Primary radiation therapy with concurrent chemotherapy is under study as definitive and palliative therapy for patients with esophageal carcinoma. To evaluate the correlation between CT staging and outcome, we retrospectively reviewed the CT scans of 48 patients treated with primary radiation therapy and concurrent chemotherapy and correlated CT staging with disease-free survival, overall survival, and site of relapse. Excluding one patient who was understaged and six patients who died of problems unrelated to esophageal carcinoma, mean survival of CT stage I, II, and III patients was 14.7, 21.3, and 5.2 months, respectively. When the CT stage is modified by the presence of nodal involvement on CT, the mean survival of stage IIn and IIIn (nodes greater than 1.5 cm in diameter) and stage IV patients (distant metastases) was 16.4, 19.2, and 10.6 months, respectively. Despite thickening of the esophageal wall greater than 3.0 cm in five patients with stage IIn cancer, mean survival was still 19.2 months. Patients with pericardial effusion had the worst survival of only 4.3 months. Stage II patients had a significantly longer (p less than 0.05) disease-free period than all other groups and the difference between stage II and III patients was highly significant (p less than 0.01). Stage II patients were also more likely to be disease-free at the time of death or last follow-up (p less than 0.05). Computed tomographic staging of esophageal carcinoma is useful in radiation therapy treatment planning and predicting outcome of patients managed with a nonsurgical technique of concurrent radiation and chemotherapy.

CT-guided laser therapy in resistant human tumors: phase I clinical trials.

Photodynamic therapy was performed on ten tumors in patients who did not respond to initial therapy and for whom no additional conventional therapy was available. A sensitizing agent (hematoporphyrin derivative [HpD]) was injected directly into each tumor under computed tomographic (CT) guidance to deliver high concentrations to the tumor and to minimize systemic toxicity. Three to 6 days after the injection, a clear Teflon sheath catheter was placed into the tumor under CT guidance. The tumor was exposed to red light (630-nm wavelength) through laser fiberoptics inserted in the sheath. The initial investigation confirmed the technical feasibility of CT-guided photodynamic therapy by means of intratumoral HpD injections and laser exposure through fiberoptics inserted in sheath catheters. The toxicity from a single treatment was minor, and the tumor response was encouraging.