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At least 613 records · Page 34Linked to original sources
PubMed2005

Pilot study of an energy conservation education program delivered by telephone conference call to people with multiple sclerosis.

OBJECTIVE: To modify and pilot test a face-to-face group energy conservation education program for delivery by group telephone teleconference to people with multiple sclerosis. PARTICIPANTS: 29 community dwelling individuals with multiple sclerosis. METHODS: The first phase of the study involved the modification of an existing energy conservation education program to accommodate teleconference delivery. The second phase involved a pilot test of the intervention using a basic pre/post intervention design. Licensed occupational therapists delivered the intervention. OUTCOME MEASURES: Fatigue severity, fatigue impact, health related quality of life, self-efficacy for performing energy conservation strategies, and use of energy conservation behaviors. FINDINGS: Using an a priori alpha of p = 0.10, paired t-tests found significant reductions in fatigue severity, fatigue impact, and improvements in the following aspects of quality of life: bodily pain and general health. Average effect size was 0.31. The most used energy conservation strategies after the course were simplifying activities, adjusting priorities, changing body position, resting, and planning the day to balance work and rest. CONCLUSION: The pilot study supports on-going development and testing of energy conservation education delivered by teleconference to people with multiple sclerosis.

Adult↗
PubMed1991

Missense mutations and evolutionary conservation of amino acids: evidence that many of the amino acids in factor IX function as "spacer" elements.

We report 31 point mutations in the factor IX gene and explore the relationship between the level of evolutionary conservation of an amino acid and the probability of a mutation causing hemophilia B. From our total sample of 125 hemophiliacs and from those reported by others, we identify 95 independent missense mutations, 94 of which occur at amino acids that are evolutionarily conserved in the available mammalian factor IX sequences. The likelihood of a missense mutation causing hemophilia B depends on whether the residue is also conserved in the factor IX-related proteases: factor VII, factor X, and protein C. Most of the possible missense mutations in generically conserved residues (i.e., those conserved in factor IX and in all the related proteases) should cause disease. In contrast, missense mutations in factor IX-specific residues (i.e., those conserved in human, cow, dog, and mouse factor IX but not in the related proteases) are sixfold less likely to cause disease. Missense mutations at nonconserved residues are 33-fold less likely to cause disease. At least three models are compatible with these observations. A comparison of sequence alignments from four and nine species of factor IX and an examination of the missense mutations occurring at CpG residues suggest a model in which most residues fall on opposite ends of a spectrum. In about 40% of residues, virtually any missense mutation in a minority of the residues will cause disease, while virtually no missense mutations will cause disease in most of the remaining residues. Thus, many of the residues in factor IX are spacers; that is, the main chains are presumably necessary to keep other amino acid interactions in register, but the nature of the side chain is unimportant.

Amino Acid Sequence↗
PubMed2006

Breast-conserving surgery in early-stage breast cancer (indications, local recurrences, survival, cosmetic results).

INTRODUCTION: Breast cancer is an extremely actual problem in modern medicine and surgery in particular. Constantly growing frequency, younger age of the newly diagnosed patients, severe psychological collapse of the patients and serious impairment of quality of life are only some of the factors determining actuality of the problem. AIM: The aim of the present survey is to make a retrospective comparative clinical analysis of the results obtained after breast-conserving surgery and simple mastectomy in terms of 5- and 10-year survival, local recurrences and cosmetic outcome. PATIENTS AND METHODS: Over a 19-year period, 269 breast cancer patients were treated in the Clinic. Breast-conserving surgery plus axillary lymph node dissection in levels I, II and III was performed in 66.17% of the patients. In 33.83% of the patients ablation of the mammary gland (simple mastectomy) plus axillary lymph node dissection was done. In both groups adjuvant radiation therapy was performed and patients with positive axillary lymph nodes were further subjected to chemotherapy. Adjuvant hormone therapy with anti-estrogen drugs was administered in estrogen positive patients. RESULTS: Study of the late (5- and 10-year) results showed that in complex treatment the recurrence rate in patients subjected to breast-conserving surgery (BCS) was 4.00% and in those treated by simple mastectomy (SM)--2.99%. The 5-year survival was 90.10% for the patients undergoing BCS and 88.89% for those treated by SM. The 10-year survival was 80.56% for the patients treated by BCS and 77.14% for those subjected to SM. CONCLUSIONS: Breast-conserving surgery is indicated in all patients in stage I and II of the disease and tumor measured up to 3.5 cm regardless of the axillary lymph nodes status. There is no statistically significant difference in the survival rate between the two compared groups and cosmetic results are much better in the patients subjected to breast-conserving surgery. When complex treatment is accomplished breast-conserving operations provide recurrence rate equal to that in simple mastectomy. Unfavorable prognostic factors for recurrence are younger age, bigger lump size, greater number of positive lymph nodes and estrogen/progesterone negative status.

Adult↗
PubMed2006

[Comparative retrospective analysis of pain afflictions in patients with lumbar discopathy receiving conservative or operative therapies].

UNLABELLED: Pain afflictions are the basic problems in patients with discopathy of the lumbar backbone. Pain control is the key therapeutic task in patients with a disease of the intervertebral disc. Degree of reduction of the pain sensations is one of the most important criteria in assessment of the treatment efficacy. THE AIM: of this study was to evaluate the pain afflictions in patients with lumbar discopathy treated with conservative and operative therapies. MATERIAL AND METHODS: 665 patients aged between 16 and 76 years with discopathy at L4-L5 and L5-S1 levels have been enrolled to the study. In estimated group 348 patients received only a conservative therapy whereas 317 patients undergone an operative procedure. Analysis has been performed based on pain rating scores: Low Back Pain Rating Scale (LBPRS), Japanese Orthopedic Association Low Back Pain Score (JOA-LBPS), Domial's pain rating score. RESULTS: Results of performed studies show that conservative and operative treatment significantly alleviate pain affliction in patients with lumbar discopathy. Complete abatement of pain afflictions more frequent refers to operated patients than those only receiving conservative therapy. Alleviation of pain afflictions within a period of three years following operating procedure is significantly higher than within analogous period of conservative treatment. Reduction of pain obtained as a result of surgical procedure in higher degree refers to limb than backbone. Treatment method does not exert an influence on nature of pain afflictions within distant period. CONCLUSIONS: Alleviation of pain afflictions within a period of three years following operating procedure is significantly higher than within analogous period of conservative treatment. Treatment method does not exert an influence on nature of pain afflictions within distant period. Patients at the age of above 50 notify the higher level of intensity of pain ailments than young patients and patients in mid age.

Adolescent↗
PubMedDate not supplied

[Conserved and variable segments of the snake phospholipase A2 amino acid domain].

Homologous amino acid sequences of phospholipases A2 of snakes belonging to families Elapidae, Viperidae and Colubridae were considered in order to study the location of conservative and variable regions. To identify significant conservative and variable regions a comparison between two groups of aligned sequences of snake phospholipases A2 was successfully applied. The phospholipases A2 sequences were divided into two groups (taxons) according to the phylogenetic tree reconstructed from the pair distance matrix. Results of the comparison were plotted to facilitate the identification of significant conservative and variable regions. It was shown, that the results of the comparison between two phylogenetic groups of snake phospholipases A2 didn't depend much on the number of each group representatives, and the location of conservative and variable regions didn't significantly change if one of the groups was represented by the single sequence. It should be mentioned, that the more the phylogenetic difference between groups of phospholipases A2 the more was the number of significant conservative and variable regions. The knowledge of the number and location of conservative and variable regions and their dependence on phylogenetic relations between the compared taxons can be used to predict the synthetic peptide structure to obtain antibodies of various specificity. These antibodies may have either a wide range of cross-reactivity against all of phospholipases A2 or a limited range of cross-reactivity against phospholipases A2 of one taxon.

Amino Acid Sequence↗
PubMed1991

Identification of a possible control element, Mt5, in the major noncoding region of mitochondrial DNA by intraspecific nucleotide conservation.

Nucleotide sequences throughout the whole major noncoding region of mitochondrial DNA of 18 subjects were determined. Previously identified control elements were classified into three groups according to the degree of intraspecific nucleotide conservations: strictly conserved elements (LSP, HSP, Mt3, Mt3 on H-strand, mtTF1-element for HSP), relatively conserved elements (CSB-III, Mt4 on H-strand, and mtTF1-element for LSP), and variable elements (TAS, CSB-I, CSB-II). Moreover, alignment of nucleotide conservations disclosed a stretch of conserved sequence (5'-ATGCTTACAAGCAAG-3', nucleotide number 16, 194-16,208, designated as Mt5 element) in the middle of the hypervariable segment. Nucleotide conservation of this element was not only intraspecific but also interspecific.

Base Sequence↗
PubMed1990

Human and mouse LSP1 genes code for highly conserved phosphoproteins.

With use of the mouse LSP1 cDNA we isolated a human homologue of the mouse LSP1 gene from a human CTL cDNA library. The predicted protein sequence of human LSP1 is compared with the predicted mouse LSP1 protein sequence and regions of homology are identified in order to predict structural features of the LSP1 protein that might be important for its function. Both the human and mouse LSP1 proteins consist of two domains, an N-terminal acidic domain and a C-terminal basic domain. The C-terminal domains of the mouse and human LSP1 proteins are highly conserved and include several conserved, putative serine/threonine phosphorylation sites. Immunoprecipitation of LSP1 protein from 32P-orthophosphate-loaded cells show that both the mouse and human LSP1 proteins are phosphoproteins. The sequences of the putative Ca2(+)-binding sites present in the N-terminal domain of the mouse LSP1 protein are not conserved in the human LSP1 protein; however, a different Ca2(+)-binding site may exist in the human protein, indicating a functional conservation rather than a strict sequence conservation of the two proteins. The expression of the human LSP1 gene follows the same pattern as the expression of the mouse LSP1 gene. Southern analysis of human genomic DNA shows multiple LSP1-related fragments of varying intensity in contrast to the simple pattern found after similar analysis of mouse genomic DNA. By using different parts of the human LSP1 cDNA as a probe, we show that most of these multiple bands contain sequences homologous to the conserved C-terminal region of the LSP1 cDNA. This suggests that there are several LSP1-related genes present in the human genome.

Amino Acid Sequence↗
PubMed1979

Industrial hearing conservation.

Hearing conservation programs, when appropriate in industry, are now a necessity. Even though one may not wish to adopt an altruistic attitude toward the conservation of hearing, one must, like it or not, initiate a hearing conservation program because of both federal and state regulations. Since industrial noise exposure produced more hearing loss in more people than all other causes of hearing loss combined, it is incumbent on all industries with noise makers to do something about protecting human hearing. The tragedy is that nearly all industrial hearing loss can be prevented with proper hearing conservation measures. The cost of hearing conservation is far less than the cost of hearing loss in terms of human suffering and dollars in the compensation courts. Proper education of both managment and labor can result in successful hearing conservation programs. The method of choice is reduction of the noise at the source, but in many cases this is infeasible both technically and economically and therefore protection at the ear must be used. Experience has shown that with proper supervision ear protection programs can prevent the majority of instances of hearing loss in the majority of individuals exposed.

Acoustics↗
PubMed1978

Developmental priority of identity conservation: acceleration of identity and equivalence in normal and moderately retarded children.

In an attempt to clarify the chronological relationship between identity and equivalence conservation, normal preschool-aged children (experiment 1) were exposed to brief videotape demonstrations of a model conserving identity and equivalence, identity only, equivalence only, or neither. Subsequent performances indicate that identity was easier to accelerate than equivalence, and training in both identity and equivalence appeared to be most effective in accelerating conservation. Trainable mentally retarded (TMR) children were then exposed to either the identity-equivalence-conserving or control model (experiment 2). This population, which some have argued remains at a preoperational level of functioning, was more likely to conserve identity than equivalence. In addition, conservation in the training group increased following training, though these gains were not maintained over a 3-week retention interval.

Child Development↗
PubMed1995

Conservative versus operative treatment of appendicular abscess. Experience of 147 consecutive patients.

One hundred and forty-seven consecutive patients who were treated for appendicular abscess were studied retrospectively, to evaluate conservative and operative treatment. 69 patients (47%) were primarily treated conservatively; of them six (9%) had to be operated on in the acute phase because of worsening of the symptoms. 78 patients (53%) were operated on primarily. Of them, 22 (28%) had complications, five (6%) needed a reoperation. Interval appendicectomy was performed in 45 patients (31%) 2-6 months after conservative treatment, and all healed well. Eighteen patients (12%) were treated conservatively only. Colography was performed in 48 patients after conservative treatment. In four, a tumour was suspected, but at operation no tumour was found in any of them. However, one caecal carcinoma was found at the interval appendicectomy, but in this case the colography did not reveal the tumour. In addition, five cases of Crohn's disease and one of diverticulitis were detected. Our findings suggest that if appendicular abscess is operated on in the acute phase, there may be more complications, but it is often not possible to make the correct diagnosis before operation. The routine of interval appendicectomy may be questioned, but adequate follow-up should be arranged. Laparotomy is indicated without delay when there is clinical suspicion of cancer, even if the colography does not reveal a tumour. For young asymptomatic patients conservative treatment with sufficient follow-up might be sufficient.

Abscess↗
PubMed1994

Conserved waters in legume lectin crystal structures. The importance of bound water for the sequence-structure relationship within the legume lectin family.

An analysis of the water structure in the crystals of different legume lectins has been carried out. Protein hydration is found to be mainly dependent on the detailed local surface characteristics of the protein and will adapt upon the limited conformational changes that are the resultant of crystal packing forces and point mutations. Yet a significant portion of the water positions determined by x-ray crystallography appears to be conserved in all independent crystal structures of a given protein. Some of these waters are specific to this one specific protein, while others are conserved in crystal structures of homologous proteins as well. For those conserved waters, a clear structural role is often evident. Seven water sites were found to be completely conserved in all legume lectin crystal structures, independent of their degree of sequence homology or carbohydrate specificity. Of these, four waters are ligands to the manganese and calcium ions, and one water is located in the saccharide binding site interacting with a conserved Asp and Asn residue. Of the remaining two conserved waters, one of them stabilizes a beta-hairpin, while the other interacts with a beta-bulge structure of the back sheet.

Amino Acid Sequence↗
PubMed1995

[Efficiency of microbank systems for the conservation of microorganisms relevant to veterinary medicine and others which are not easy to cultivate].

In this paper the conservation of different bacteria, yeasts and molds from diagnostic material was examined with a commercial deep freeze system. 137 bacteria isolated from the stomachs of dogs, cats and pigs and from duodenal juice of cats and 7 isolates of yeasts and fungi from diagnostic material were conserved with the deep freeze system MICROBANK-TM (Mast Diagnostica). Furthermore 62 Helicobacter pylori-isolates and 1 Helicobacter felis-isolate were conserved with this system. After a storage period of 24 hours up to 20 months the isolates were recultured. 96% of the conserved microorganisms could be grown. It was not possible to cultivate 1 fungus-isolate (Fusarium sp.). 2 Helicobacter pylori-isolates, spiral bacteria from the stomach of a pig and a Clostridium tyrobutyricum-isolate were only recultured after 24 hours, 1 isolate Moraxella sp. after 2 months and another 4 anaerobe isolates after 5 months. The system MICROBANK-TM proved to be suitable for conservation and was also efficient for the conservation of microorganisms, which could not easily be cultivated.

Animals↗
PubMed1996

[Treatment outcome and complications of surgical and conservative management of mandibular fractures].

Retrospective analysis of 712 patients with 1166 mandibular fractures and follow up-study of 374 patients with 593 fractures was performed for discrimination of differences in wound- and bone-healing as well as late results between operative and conservative fracture treatment. 46.1% (328) of all patients have been treated conservatively, 53.9% (384) have been treated by operation. The follow up was performed on 255 patients with operative fracture treatment and 119 patients with conservative treatment. In 3.0% of the operatively treated patients bacterial infections occurred, in comparison to 8.7% of conservatively treated patients. From the viewpoint of functional aspects, such as occlusion, articulation and mandibular movement as well as radiological signs in the fractured region patients after operative treatment have shown partly significantly better results during the follow up compared to the group of conservatively treated patients. Neurological testings of inferior alveolar nerve and mental nerve have shown significantly better results in the group of conservatively treated patients. Since the functional results are much better after operative treatment, osteosynthesis with miniplates should be performed if there are no contraindications. The more precise reconstruction and stabilization of the fragments shortens time of hospitalization and leads to sooner functionality of the mandible.

Bone Plates↗
PubMedDate not supplied

Conservative management of spinal osteoarthritis with glucosamine sulfate and chiropractic treatment.

OBJECTIVE: To evaluate the rationale behind the most commonly used treatments of osteoarthritis, including nonsteroidal anti-inflammatory drugs (NSAIDs), and to assess more effective conservative treatment options. SUMMARY OF BACKGROUND DATA: This review includes a description of the pathophysiology and prevalence of osteoarthritis, joint physiology and NSAID treatment of osteoarthritis, as well as side effects on joints, the gastrointestinal tract, kidneys and livers. Several studies of conservative treatment, consisting of supplementation of glucosamine sulfate (which occurs naturally in the human body), exercise, and the use of chiropractic treatment for maintaining joint function and preventing further destruction, are reviewed. DATA SOURCES: A computerized search of Medline using the key indexing terms osteoarthritis, degenerative joint disease, nonsteroidal anti-inflammatory drugs, glucosamine sulfate, chiropractic and manipulation. RESULTS: Numerous studies wee obtained under each subheading and reviewed by category. Human and animal-model studies are described. CONCLUSION: The rationales for using NSAIDs in the treatment of osteoarthritis is controversial and openly contested. Given the detrimental effects of NSAIDs on joints and other organs, their use should be discouraged and their classification as a first choice conservative treatment should be abolished. A truly effective and conservative approach to the treatment of osteoarthritis should include chiropractic manipulation, essential nutrient supplementation, exogenous administration of glucosamine sulfate and rehabilitative stretches and exercises to maintain joint function. Because there is no correlation between pain levels and the extent of degeneration detected by radiographic or physical examination, conservative treatment should be initiated and sustained based on functional, objective findings and not strictly on how the patient feels. The use of NSAIDs should be limited to the treatment of gross inflammation and analgesics should only be used in the short-term when absolutely necessary for pain palliation. The present conservative approach could lead not only to a better quality of life but also to the saving of health care dollars by reducing the iatrogenic morbidity and mortality associated with NSAID use.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1997

[Hip dislocations and hip fractures--acetabular fractures. Indication, technique and results of conservative treatment].

Despite the great number of publications during the last 10 years concerning the indication, technique and results of operative treatment of acetabular fractures, conservative treatment still has an important role when considering the therapeutic possibilities. Because of the modern techniques of radiological imaging and improvement of diagnostic facilities, a more defined indication for treatment becomes possible. Conventional X-rays, completed by special projections like the Ala and Obturator view, and a CT scan allow determination of the fracture type (the Letournel/Judet classification or the AO classification). The most suitable treatment can then be adapted to the individual circumstances of the patient, i.e., age, general condition and overall severity of traumatic impairment. Determination of the intact part of the weight-bearing dome is important in selecting the most adequate therapeutic procedure. The larger the intact roof arc, the better the prognosis. Together with the X-ray controls following axial and facultative lateral extensions, the indication for conservative treatment can be confirmed. Early active motion of the injured limb, followed by walking exercises with partial weight-bearing, are important aspects of nonoperative treatment. Conservative treatment is recommended in non-displaced fractures or in fractures with little displacement, transverse fractures of the lower region or severely comminuted acetabular fractures with no possibility of reconstruction. Our clinical and radiological follow-up of 97 patients with acetabular fractures from the years 1981-1990 showed that the majority were treated conservatively (approx. 70%). The functional result after an average observation period of more than 70 months was good or excellent (based on the Merle d'Aubigné score). We feel it is important to look at operative and conservative treatment of acetabular fractures as two complementary non-competitive therapeutic methods. The choice of treatment should be based on an exact diagnosis considering fracture type, the individual circumstances of the patient, and application of the necessary diagnostic facilities. Conservative treatment can lead to excellent long-term results.

Acetabulum↗
PubMed1997

[Acute type B aortic dissection: prognosis after initial conservative treatment and predictive factors for a complicated course].

OBJECTIVE: Today there is still debate concerning the optimal mode of treatment for type B dissection of the aorta. Controversies are mainly due to discordant results regarding survival following medical or surgical treatment. We assessed the early and long-term outcome of acute dissection of the descending aorta after initial conservative treatment. METHODS: Between 1980 and 1995, 225 patients were hospitalized in the medical or surgical department of our institution with the diagnosis of acute type B aortic dissection. 38 patients (16.8%) underwent replacement of the descending aorta within the first week after hospital admission. Primary indications for immediate surgery were rupturing aneurysm in 15 patients, extensive dilatation of the descending aorta in 13, distal malperfusion in 8, and pseudocoarctation syndrome with uncontrollable hypertension in 2. All other patients (n = 187) underwent primary conservative treatment in the intensive care unit, which included appropriate antihypertensive medication. RESULTS: Hospital mortality during and after initial conservative treatment was 17.6% (33/187 patients). Main causes of death were rupture in 14 patients, intestinal malperfusion in 13 and cardiac failure in 3, whereas in 3 patients the cause of death could not be determined. Nine additional patients had to be referred for early surgery during the initial hospitalization because of contained rupture (n = 4), rapidly increasing size of the aorta (n = 2) and suspected intestinal ischemia (n = 3). Hospital mortality after early surgery was 21% (8/38 patients) for the overall time period. After hospital discharge from the initial acute dissection, surgery for chronic dissection was performed in 47 patients, mainly because of expanding descending aortic aneurysm. Hospital mortality was 8% in these patients (4/47). Actuarial survival rates after primary conservative therapy were 76 +/- 5% and 50 +/- 7% after 5 and 8 years respectively. CONCLUSION: Currently, surgery for acute type B dissection is limited to patients with rupturing disease, distal malperfusion or uncontrollable hypertension and pains. Despite aggressive antihypertensive treatment, hospital mortality after primary conservative treatment is still high and a substantial proportion of patients requires surgery during initial hospitalization. Although conservative treatment is recommended in most uncomplicated type B aortic dissections, early surgery should be considered in the following situations: younger patients with 5 cm diameter of the aorta at initial evaluation, as well as those with Marfan syndrome, patients with limited false aneurysm or retrograde dissection into the aortic arch, and those with poor medical compliance or uncontrollable proximal hypertension. Radiographic follow-up for an indefinite period may allow detection of potential late complications and proper planning of elective operations when indicated.

Acute Disease↗
PubMed1997

[The conservative treatment of major kidney injuries].

The choice of treatment (surgical or conservative) for major renal trauma still remains controversial. The objective of this study was to compare the results of patients with major renal trauma (grade III and IV) primarily treated by surgical intervention (1980-1992) with those in patients mainly treated conservatively (1992-1995). Between 1980 and 1995, 83 patients with major renal trauma were hospitalized at our institution. Our results show a higher nephrectomy rate of 44% in the case of primary surgical intervention compared to conservative management (27%). The outcome of twenty-two patients treated conservatively was analyzed prospectively with repeated radiological imaging, blood pressure profiles, and renal function assessment by means of MAG 3 renal scintigraphy. No patient developed renovascular hypertension and the relative function of the traumatized kidney was greater than 40% in 95% of patients. In conclusion, our results confirm a lower nephrectomy rate in the case of conservative management without any increase of the immediate or long-term morbidity. Major renal trauma (grade III, IV) can therefore be effectively treated by conservative management and primary surgical repair is only indicated in patients with hemodynamic instability, persistent hematuria and associated visceral injuries.

Adolescent↗
PubMed1997

Breast irradiation in women with early stage invasive breast cancer following breast conservation surgery. Provincial Breast Disease Site Group.

GUIDELINE QUESTIONS: 1) Should breast irradiation be given to women with early stage invasive breast cancer (stage I and II) following breast conservation surgery (lumpectomy with clear resection margins and axillary dissection)? 2) Is there an optimal schedule for breast irradiation? 3) What is a reasonable interval between definitive surgery and the start of breast irradiation? 4) Are there patients who can be spared breast irradiation after lumpectomy? OBJECTIVE: To make recommendations about the use of breast irradiation in women with early stage invasive breast cancer following breast conservation surgery. OUTCOMES: Local control is the primary endpoint of interest. Survival, quality of life (addressed through the adverse effects of radiotherapy) and cosmesis are also considered. PERSPECTIVE (VALUES): Evidence was selected and reviewed by 6 members of the Breast Disease Site Group (Breast DSG) of the Ontario Cancer Treatment Practice Guidelines Initiative. Earlier drafts of the evidence-based recommendation were reviewed, discussed and approved by the Breast DSG, which comprises medical oncologists, radiation oncologists, surgeons, epidemiologists, pathologists and a medical sociologist. There was no participation by a community representative in the development of this guideline. QUALITY OF EVIDENCE: There are 5 randomized controlled trials (RCTs) and 1 meta-analysis comparing breast irradiation with no breast irradiation following breast conservation surgery; 6 randomized trials comparing breast conservation surgery plus breast irradiation with mastectomy are also included, as well as several retrospective studies. BENEFITS: All of the 5 RCTs showed a significant decrease in local recurrence rates among patients receiving radiotherapy. In the 4 trials with a median follow-up of 5 years or longer, the relative risk reduction with breast irradiation ranged from 69% to 88%. The absolute differences ranged from 16% (p < 0.001) to 25% (p < 0.001). Despite the effect on local recurrence, no difference in survival was detected in any of the 5 trials. Most of the patients with local recurrence in these trials underwent mastectomy. HARMS: Major adverse effects of breast irradiation occur very infrequently. PRACTICE GUIDELINE: Women with early stage invasive breast cancer (stage I and II) who have undergone breast conservation surgery should be offered postoperative breast irradiation. The optimal fractionation schedule for breast irradiation has not been established, and the role of boost irradiation is unclear. Outside of a clinical trial, 2 commonly used fractionation schedules are suggested: 50 Gy in 25 fractions to the whole breast, or 40 Gy in 16 fractions to the whole breast with a local boost to the primary site of 12.5 Gy in 5 fractions. Shorter schedules (e.g., 40 or 44 Gy in 16 fractions) have also been used routinely in some centres. The enrollment of patients in ongoing clinical trials is encouraged. Women who have undergone breast conservation surgery should receive local breast irradiation as soon as possible after wound healing. A safe interval between surgery and the start of radiotherapy is unknown, but it is reasonable to start breast irradiation within 12 weeks after definitive surgery. For women who are candidates for chemotherapy, the optimal sequencing of chemotherapy and breast irradiation is unknown. It is reasonable to start radiotherapy after the completion of chemotherapy, or concurrently if anthracycline-containing regimens are not used. For further information, please refer to Ontario Cancer Treatment Practice Guidelines Initiative's practice guideline "Surgical Management of Early Stage Invasive Breast Cancer (stage I and II)."

Breast Neoplasms↗