Refined estimates of local recurrence risks by DCIS score adjusting for clinicopathological features: a combined analysis of ECOG-ACRIN E5194 and Ontario DCIS cohort studies.

PURPOSE: Better tools are needed to estimate local recurrence (LR) risk after breast-conserving surgery (BCS) for DCIS. The DCIS score (DS) was validated as a predictor of LR in E5194 and Ontario DCIS cohort (ODC) after BCS. We combined data from E5194 and ODC adjusting for clinicopathological factors to provide refined estimates of the 10-year risk of LR after treatment by BCS alone. METHODS: Data from E5194 and ODC were combined. Patients with positive margins or multifocality were excluded. Identical Cox regression models were fit for each study. Patient-specific meta-analysis was used to calculate precision-weighted estimates of 10-year LR risk by DS, age, tumor size and year of diagnosis. RESULTS: The combined cohort includes 773 patients. The DS and age at diagnosis, tumor size and year of diagnosis provided independent prognostic information on the 10-year LR risk (p ≤ 0.009). Hazard ratios from E5194 and ODC cohorts were similar for the DS (2.48, 1.95 per 50 units), tumor size ≤ 1 versus  > 1-2.5 cm (1.45, 1.47), age ≥ 50 versus < 50 year (0.61, 0.84) and year ≥ 2000 (0.67, 0.49). Utilization of DS combined with tumor size and age at diagnosis predicted more women with very low (≤ 8%) or higher (> 15%) 10-year LR risk after BCS alone compared to utilization of DS alone or clinicopathological factors alone. CONCLUSIONS: The combined analysis provides refined estimates of 10-year LR risk after BCS for DCIS. Adding information on tumor size and age at diagnosis to the DS adjusting for year of diagnosis provides improved LR risk estimates to guide treatment decision making.

Metal ion and salt effects on the phospholipase A2, lysophospholipase, and transacylase activities of human cytosolic phospholipase A2.

Human cytosolic phospholipase A2 (cPLA2) is an arachidonic acid specific enzyme which may play a role in arachidonic acid release, eicosanoid production, and signal transduction. The PLA2 activity of this enzyme is stimulated by microM levels of Ca2+. Using a pure recombinant enzyme, we have confirmed that cPLA2 is not absolutely dependent on Ca2+, since Sr2+, Ba2+ and Mn2+ also gave full enzyme activity. Heavy metals, in contrast, inhibited enzyme catalysis suggesting the involvement of an essential cysteine residue. In the absence of Ca2+, high salt concentrations overcame the requirement for divalent metals, indicating that Ca2+ is not required for PLA2 catalytic activity. cPLA2 also displays a lysophospholipase (lyso PLA) activity with lysophosphatidylcholine micelles as a substrate. Unlike the PLA2 activity, the lyso PLA activity toward these micelles is not stimulated by Ca2+. However, upon the addition of glycerol or Triton X-100 to the assay, Ca2+ activation is observed, indicating that substrate presentation can affect the apparent Ca2+ dependence. Glycerol was found to be a potent stimulator of lyso PLA activity and specific activities up to 50 mumol min-1 mg-1 were observed. In addition to the PLA2 and lyso PLA activities, we report that cPLA2 displays a relatively low, CoA-independent transacylase activity which produces phosphatidylcholine from lysophosphatidylcholine substrate. The observation of this novel transacylase activity is consistent with the formation of an acyl-enzyme intermediate.

Minimal toxicity and mortality in high-risk breast cancer patients receiving high-dose cyclophosphamide, thiotepa, and carboplatin plus autologous marrow/stem-cell transplantation and comprehensive supportive care.

PURPOSE: To assess the clinical toxicity and outcome associated with a comprehensive supportive care approach in poor-risk breast cancer (BrCA) patients with high-dose chemotherapy (HDC). PATIENTS AND METHODS: One hundred twenty-five consecutive patients with stages II, III or metastatic breast cancer received HDC between February 1992 and June 1994. Recipients received 4 days of continuous infusion of cyclophosphamide 1.5 g/m2/d, thiotepa 125 mg/m2/d, and carboplatin 200 mg/m2/d followed by infusion of bone marrow or peripheral-blood stem cells (PBSC) and recombinant human growth factor (rhu-GF) support. Patients received similar supportive care that included administration of prophylactic antibiotics, management of neutropenic fevers, and transfusion support. RESULTS: There were 38 women with stage II or III (27 patients with > or = 10 lymph nodes), four with stage IIIB, and 83 with metastatic breast cancer. The median age was 44 years (range, 27 to 61). Grade II or greater nonhematologic toxicities included diarrhea (66%), stomatitis (33%), hepatic venoocclusive disease (VOD) (5%), and pulmonary toxicity (4%). Myeloid and platelet engraftment was comparable between bone marrow and PBSC recipients (P > .1). Infectious complications were rare and consisted of gram-negative bacteremia (1.6%), gram-positive bacteremia (1.6%), fungemia (1.6%), and documented or suspected aspergillosis infection (3%). There was one treatment-related death secondary to severe VOD. CONCLUSION: A comprehensive supportive care approach was associated with a low treatment-related mortality rate of less than 1%. With the observed reduction in treatment-related mortality, it is reasonable to evaluate the efficacy of HDC in women with less than 10 positive nodes and stage II disease in well-designed clinical trials.

Radiosensitization of cultured human colon adenocarcinoma cells by 5-fluorouracil: effects on cell survival, DNA repair, and cell recovery.

Although 5-fluorouracil (5-FU) is commonly used in conjunction with radiotherapy to treat gastrointestinal malignancies, the molecular mechanisms underlying the clinically observed therapeutic advantage of this combination of agents have not been clearly established. The present in vitro studies addressed the possibility that the radiosensitization of log-phase cultured human colon adenocarcinoma cells by postirradiation administration of 5-FU was accompanied by an interference either with the rejoining of radiation-induced DNA double-strand breaks (DSB's) or with recovery from potentially lethal damage (PLD). Significantly more killing was observed in cells exposed to gamma-rays (1-6 Gy) and then treated with 5-FU (100 micrograms/mL; 0.77 mM) for 1 hr at 37 degrees C than in cells given gamma-rays but not 5-FU; essentially, the survival curve shoulder was removed. DSB rejoining measured using the neutral filter elution method after exposure to 25 Gy was identical regardless of whether 5-FU (100 micrograms/mL) was present during the repair period; thus, radiosensitization by this high-concentration postirradiation 5-FU protocol does not appear to be a result of interference with the overall rate of ligation of gamma-ray-induced DSB's. The effect of 5-FU on the ability of log-phase cells to recover from that sector of PLD that can be expressed by postirradiation incubation with hypertonic (0.5 M) salt solution (HSS) was also examined. When irradiated cells were treated with 5-FU during their recovery period and then incubated with HSS, no clonogenic cells survived. Therefore, although it was not possible to assess the actual kinetics of recovery from gamma-ray-induced PLD in 5-FU-treated cells, the drug clearly altered the metabolism or structure of the cells such that their susceptibility to HSS was markedly enhanced.

Radiotherapy for anal cancer: experience from 1979-1987.

Seventy patients with squamous cell carcinoma or cloacogenic carcinoma of the anus treated from 1979-1987 were reviewed. Five groups were analyzed: (a) local excision (LE) with postoperative radiotherapy (n = 9); (b) abdominoperineal resection (APR) with either pre- or postoperative radiotherapy (n = 22); (c) definitive radiotherapy alone (n = 8); (d) radiotherapy with continuous 5-Fluorouracil (5-FU) infusion (chemoradiation) (n = 25); and (e) patients treated for recurrent disease (n = 6). Abdomino-perineal resection and radiotherapy resulted in an actuarial local control (LC) rate of 90% and an overall 5-year survival rate of 77% (median follow-up, 48 months). All patients in Group 1 and 5/8 patients in Group 3 had locally controlled disease and were disease-free. The chemoradiation protocol resulted in a complete clinical response rate of 75% (18/24, one patient died during treatment) assessed 4-6 weeks after treatment. The colostomy-free local control rate with chemoradiation is 67% (16/24). Local control was 50% for all stages receiving 45-49 Gy and 90% for those patients receiving greater than or equal to 55 Gy but was not correlated with total 5-FU dose. Abdomino-perineal resection was performed to salvage six patients with persistent disease and two with recurrent disease, resulting in an overall local control rate of 92% (22/24). The actuarial survival was 96% (median follow-up, 14 months; range, 1-30). The acute complications of radiotherapy included diarrhea and perineal skin reactions that were increased by 5-FU infusion. However, diarrhea can be ameliorated by a modified treatment technique that reduces irradiation to the small intestine. For the entire patient group, minor late complications occurred in 23%, and major complications occurred in 9%.

Palliation of recurrent endometriosis with radiotherapeutic ablation of ovarian remnants.

OBJECTIVE: To review the use of radiotherapy for relieving the symptoms of recurrent endometriosis caused by functioning ovarian remnants. DESIGN: Retrospective study (case report). PATIENT(S): A woman with recurrent endometriosis of 14 years' duration. INTERVENTION(S): After hysterectomy and bilateral oophorectomy, hormonal management, and multiple explorations for recurrent endometriosis, cycling ovarian remnants were confirmed histologically. Pelvic irradiation was used to ablate this tissue. A dose of 15 Gy in 10 daily fractions was given through anterior and posterior opposed fields using 18-mV photons. RESULT(S): The patient had a prompt increase in FSH levels associated with castration levels of serum E2. A review of the literature on the use of radiotherapy in this clinical situation is presented. CONCLUSION(S): Radiotherapy should be considered in selected patients when ovarian castration is not a viable surgical option and hormonal therapies have failed.

A totally integrated simulation technique for three-field breast treatment using a CT simulator.

A method was devised to simulate patients with breast cancer in the actual treatment position utilizing a diagnostic CT spiral scanner, 3-D Image Workstation for virtual simulation, and a laser coordinate system to transfer planning parameters to the patient's skin. It was desired to produce non-divergent tangential beams through the lung as well as a matched line for tangential and supraclavicular fields. The patients were immobilized in an Alpha CradleTM cast. Radio-opaque markers were placed on the superior, inferior, medial, and lateral margins of the field so as to afford appropriate initial field set-up approximations. The patient was scanned. The data set was then transferred to the workstation where an isocenter was chosen. The patient was marked. Virtual simulation was then performed. This method employed a half beam technique for the posterior edge of the tangential fields. Table rotation and blocking of the superior margin of the tangential fields were used to produce a vertical edge to match a supraclavicular field. Using a beam's eye view the lateral tangent was matched to the medial exit. A digitally reconstructed radiograph was created to define the tangent fields and place the supraclavicular block. Our initial experience with 50 patients verifies that this is a reproducible and accurate technique. Time required for immobilization and tangential field simulation is approximately 30 minutes. Data is available for 3-D treatment planning or 2-D treatment planning on a reconstructed transverse slice angled to match the collimator angle through the patient. Using a CT simulator for simulation of breast cancer affords accuracy of at least equal magnitude to conventional simulators as determined by beam films and ease of set-up. This technique also affords greater ease in changing treatment parameters without having to resimulate the patient.

Cellulitis of the breast as a complication of breast-conserving surgery and irradiation.

Breast-conserving therapy (BCT) has become a standard treatment option for patients with early-stage breast cancer. We have observed cellulitis of the treated breast as a complication occurring before, during, and after breast irradiation. The cases of five women (median follow-up, 28 months; range, 24-65 months) who developed cellulitis before (n = 1), during (n = 2), or after (n = 2) breast irradiation were reviewed. A consecutive series of BCT patients at Emory University was reviewed to determine the incidence of this complication. Four of five women had an axillary dissection, yielding a median of 14 negative lymph nodes (range, 6-22 nodes). Two of four patients developed axillary seromas requiring aspiration. In these four patients, only the breast was irradiated. A fifth patient had no axillary dissection and had breast and supraclavicular/axillary irradiation. The median whole breast dose was 50 Gy (range, 46-50.4 Gy). The clinical features of cellulitis included erythema, edema, tenderness, and warmth in all patients. Cellulitis was a relapsing problem for four of the five patients. The incidence of this complication in our series of BCT patients was approximately 1%. Cellulitis in the ipsilateral breast can be a relapsing complication of BCT and can be seen before, during, or after breast irradiation. Axillary seromas and aspiration seem to indicate a subset of patients at risk of early cellulitis. Late cellulitis may be caused by a variety of factors related to modifications of vascular and skin integrity by surgery and radiotherapy. Prompt diagnosis and appropriate antibiotic therapy is recommended. This problem need not interrupt a course of breast irradiation, and does not necessarily lead to a poor cosmetic result.

Conservative treatment of early-stage breast cancer. The Emory experience.

Between January 1983 and December 1991, 80 women with AJCC clinical stage I or II breast cancer were treated with conservative surgery and radiation therapy. Reexcision of the primary was performed in 40 breasts, and residual tumor was identified in 40% of these. Margins of resection were assessed in 80% and, of these, 46 patients had final margins of resection that were negative, 86% had axillary node dissection, 45 patients had histologically negative axillary nodes, and 24 had histologically positive axillary nodes. Of patients with histologically positive lymph nodes, 92% received systemic adjuvant treatment consisting of chemotherapy in 19/24 and tamoxifen in 14/24. Median follow-up was 34 months (range: 6-90 months). The adjusted 5-year actuarial Overall Survival for the group was 92%, and Disease-Free Survival was 80%. The 5-year Local Recurrence-Free Survival was 96%. The present study confirms the excellent results that can be obtained with conservative surgery plus radiation therapy.

Conservative treatment of early-stage breast cancer in a medically indigent population.

The compliance with a program of breast-conservation treatment for early-stage breast cancer and the results of that treatment among women treated between January 1983 and January 1992 was investigated in a large inner-city public hospital serving a primarily black population. Medical records and charts were reviewed for 25 consecutive patients with stage I and II breast cancer seen in consultation in the radiation oncology department. Of those 25 patients, 20 underwent lumpectomy and radiation therapy. Survival, disease-free survival, and local recurrence-free survival were computed using the Kaplan-Meier method. Compliance was evaluated based on time to complete the prescribed course of radiotherapy after a lumpectomy. Five-year local recurrence-free survival for stage I and II patients was 95% (confidence interval [CI]: 71% to 99%). Five-year overall survival for stage II patients was 71% (CI: 31% to 92%), and disease-free survival was 74% (CI: 36% to 91%). This study demonstrates that a program of breast-conservation treatment for early-stage breast cancer can be implemented with good results, excellent treatment compliance, and 100% follow-up in a population of medically indigent women.

Analysis of human synovial fluid phospholipase A2 on short chain phosphatidylcholine-mixed micelles: development of a spectrophotometric assay suitable for a microtiterplate reader.

The development of a reliable assay for human synovial fluid phospholipase A2 (HSF PLA2) is important for the kinetic characterization of the enzyme and for the identification of enzyme inhibitors. This enzyme behaves differently from other extracellular PLA2s in many standard phospholipase assays and is generally assayed using radiolabeled, autoclaved Escherichia coli as a substrate. We have now developed a nonradioactive, continuous, spectrophotometric assay for this enzyme that is adaptable for use with a microtiterplate reader and is suitable for screening enzyme inhibitors. The assay uses a thioester derivative of diheptanoyl phosphatidylcholine as a substrate, with which the enzyme displays a specific activity of about 25 mumol min-1 mg-1. The substrate concentration curve fits a Hill equation with an apparent Km of 500 microM and a Hill coefficient of two. The enzyme has a pH optimum of 7.5 in this assay and requires about 10 mM Ca2+ for maximal activity. The presence of 0.3 mM Triton X-100 was necessary to solubilize the substrate; however, higher concentrations of the detergent inhibited enzyme activity. Using this spectrophotometric assay, inhibition of HSF PLA2 by a thioether phosphonate phosphatidylethanolamine analog was observed with an IC50 of 18 microM.

1-Hexadecyl-2-arachidonoylthio-2-deoxy-sn-glycero-3-phosphorylcholine as a substrate for the microtiterplate assay of human cytosolic phospholipase A2.

Human cytosolic phospholipase A2 (cPLA2) is an 85-kDa protein which displays a preference for arachidonoyl phospholipids as substrates. This substrate preference and the assay characteristics of the enzyme are quite different from those of the smaller, more well-studied extracellular PLA2s. We now report the development of a nonradioactive, spectrophotometric, microtiterplate assay for human cPLA2 using a novel synthetic thio-phospholipid analog as a substrate. This substrate is a phosphatidylcholine derivative with an arachidonoylthioester in the sn-2 position and an alkyl-ether in the sn-1 position. The use of an sn-1 alkyl-ether in the substrate ensures that the assay will only measure PLA2 activity and will not be complicated by the metabolism of the lysophospholipid product by the enzyme's lysophospholipase activity. cPLA2 is assayed at pH 7.4 and 37 degrees C with a mixed micellar substrate consisting of 2 mM thio-phospholipid and 4 mM Triton X-100 in 30% glycerol. Under these conditions, the assay is fairly linear for over 1 h.

Inactivation of secretory phospholipase A2 by ionizing radiation.

The extracellular phospholipase A2s (PLA2) from cobra venom, rattlesnake venom, and porcine pancreas were analyzed by radiation inactivation to determine their functional aggregation states. The analysis was performed in the presence of the protein transferrin at two different concentrations of PLA2: 5 micrograms/ml. The small size of these proteins necessitated the use of high radiation dosages. The catalytic activity of all samples decreased as a single exponential as a function of radiation dosage, to > 97% inactivation. Target size analysis of these curves yielded sizes corresponding to dimers for all three PLA2s, indicating that all three enzymes exist as dimers or larger aggregates under the conditions studied. An analysis of the amount of intact protein remaining by sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed that the loss of protein also followed a dimeric size for all three PLA2s. The loss of protein as a dimer indicates that transfer of radiation energy is occurring between polypeptides.

Paratesticular rhabdomyosarcoma: delayed effects of multimodality therapy and implications for current management.

BACKGROUND: The combined modalities of surgery, chemotherapy, and radiation therapy have greatly improved the survival rate in childhood paratesticular rhabdomyosarcoma, but the incidence of complications and late side effects is a cause for concern. METHODS: We reviewed the records of 18 patients treated for paratesticular rhabdomyosarcoma at St. Jude Children's Research Hospital between 1962 and 1989. Patients with Group I disease were treated with orchiectomy, retroperitoneal lymph node dissection, and multi-agent chemotherapy; more advanced cases also received radiation therapy with concurrent chemotherapy. RESULTS: Sequelae included esophageal and common bile duct stricture, inguinal nerve entrapment syndrome, and small bowel obstruction. Short stature was found in all children whose spines were irradiated via para-aortic fields (34-37 Gy) prior to puberty. Two of 18 patients died from treatment complications and one from progressive disease. CONCLUSIONS: Multimodality treatment offers an excellent prognosis in paratesticular rhabdomyosarcoma, but is associated with significant morbidity and mortality rates. A discussion of therapy components and their application to disease stages suggests possible approaches to optimizing treatment for this therapy-sensitive malignancy.