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F Saran

Publications and source records attributed to F Saran.

18 recordsLinked to original sources
PubMed2000

A Comparison of clinical target volumes determined by CT and MRI for the radiotherapy planning of base of skull meningiomas.

PURPOSE: To assess the utility of image registration and to compare the localization of clinical target volumes (CTV) using CT and MRI for patients with base of skull meningiomas undergoing radiotherapy. METHODS AND MATERIALS: Seven patients were imaged using CT and a T1-weighted MR volumetric sequence. Following image registration using a chamfer-matching algorithm, transaxial MR slices were reconstructed to match the planning CT slices. The accuracy of the image fusion was assessed in a preliminary study with matching accuracy better than 1.5 mm. The CTV in each patient was separately segmented by two independent observers for both CT and reconstructed MR image sets. Scalar and vector assessments were made of the difference in radial extent between the two outlines on each transaxial plane for all patients. A positive vector value corresponded to a greater extension of the tumor on MR compared to CT and vice versa. Scalar measurements compared the modulus of the differences between MR and CT, regardless of which volume was more extensive. Qualitative comparisons were also performed. RESULTS: Interobserver difference was small with a mean (+/- 1SD) volume difference of 1.5 +/- 1.5 cm(3) for CT and 0.5 +/- 1.0 cm(3) for MRI. The mean CT- and MR- CTVs were 17.6 +/-10.8 and 19.6 +/-14.2 cm(3) respectively. The mean overlap and composite volumes were 13.8 +/-10. 1 and 23.3 +/-14.8 cm(3) respectively. Average scalar differences in the left, right, anterior, and posterior directions were 6.0 +/- 7.0, 3.3 +/- 2.5, 4.9 +/- 3.9, and 4.5 +/- 5.0 mm respectively. The average vector differences were 3.3 +/- 8.5, -0.3 +/- 3.8, 1.1 +/- 5. 8, 1.5 +/- 6.4 mm (for left, right, anterior, and posterior directions respectively). Qualitatively, MR appeared to discern more tumor involvement in soft tissue regions adjacent to the skull base whereas CT appeared to provide larger target volumes within bony regions. CONCLUSIONS: MRI appeared to define CTVs that were larger but not inclusive of CT-defined CTVs. Although the average vector differences were small, the differences on individual borders could be large. In some instances, the CT or MR volumes were vastly different, each providing separate information. Therefore, the use of MRI and CT is complementary. Until accurate histological confirmation of disease extent is available, it is prudent to consider composite CT/MR volumes for the radiotherapy planning of base of skull meningiomas.

Adult↗
PubMed1999

Value of a multileaf prescription preparation system for palliative external beam irradiation.

In palliative treatment, irregularly shaped fields are used to reduce side-effects and can improve, or avoid, field matching. We investigated the effectiveness of a multileaf collimator (MLC) supported by a digitizing data entry system in the palliative radiotherapy treatment of 66 patients and compared it with conventional shielding with geometrically shaped blocks. After conventional simulation of rectangular fields, irregular field shapes were marked on the simulator film in 17 patients (27%) to reduce radiotherapy related side-effects. Individual leading was performed with an MLC. Digitizing and fitting of the optimum leaf position were carried out using a multileaf preparation system (MLP, Elekta, Crawley, UK). Target volumes included bone metastases in the pelvis, spine and extremities, mediastinal soft tissues, lymph nodes and central nervous system. In 10 patients, treated with a parallel pair for pelvic metastases, MLC and conventional shielding were prospectively compared with regard to time requirements and area shielded. Compared with conventional blocking, the mean simulation, preparation and treatment time required for MLP fields was shorter (9.55 +/- 1.44 min vs 16.90 +/- 2.64 min, and 5.50 +/- 1.14 min vs 8.97 +/- 1.75 min). The mean shielded area was 31 cm2 larger for MLC fields compared with geometrically shaped blocks (p < 0.05). Compared with cerrobend blocking, the use of an MLC, supported by preparation data entry software, is more flexible and reduces radiotherapy resources. Therefore, a preparation data entry system as a separate device, or integrated into the treatment planning system, is a useful tool in palliative treatment.

Bone Neoplasms↗
PubMed1999

Radiotherapy in the treatment of benign meningioma of the skull base.

OBJECT: This study was undertaken to assess the long-term efficacy and toxicity of conventional fractionated external-beam radiation in the treatment of benign skull base meningioma. METHODS: This is a retrospective study of 82 patients with histologically verified benign skull base meningioma treated by surgery followed by fractionated external-beam radiation at the Royal Marsden Hospital between 1962 and 1992. The 5- and 10-year progression-free survival (PFS) rates were 92% and 83%, respectively, with the site of disease being the only independent prognostic factor for tumor control according to multivariate analysis. The 10-year PFS rate for patients with sphenoid ridge meningiomas was 69% compared with 90% for those with tumors in the parasellar region. The overall 10-year survival rate was 71%, with performance status and patient age found to be significant independent prognostic factors. Six patients had worsening vision, which was due to cataract in five cases and retinopathy in one. There were no recorded cases of cranial nerve neuropathy. CONCLUSIONS: The excellent long-term tumor control and length of survival with minimal toxicity associated with conventional external-beam radiation should serve as a baseline for evaluation of new treatment strategies such as radiosurgery and skull base surgery.

Adolescent↗
PubMed1998

The use of a standardized positioning support cushion during daily routine of breast irradiation.

PURPOSE: The use of positioning and immobilization techniques during external beam irradiation of the female breast is time consuming and expensive. The currently available standardized positioning devices are insufficient. For this reason, we designed a new and generally useable hard foam positioning support cushion for the use during breast irradiation, and tested its clinical usefulness in a prospective study. METHODS AND MATERIALS: Fifty-five female breast cancer patients receiving adjuvant radiotherapy following breast-conservative surgery were irradiated either without immobilization (n = 27) or with the positioning support cushion (n = 28). The time necessary for patient setup, the lying subjective comfort and--comparing portal images with simulator images--the reproducibility of the set up were determined. RESULTS: Irradiation reproducibility was significantly improved (average deviation without positioning support cushion: 8.4 mm, with positioning support cushion: 6.1 mm, p < 0.001). The time required for the positioning of the patient with positioning support cushion was in average 73 s, without cushion it was 55 s. A significantly higher proportion of patients (72%) found the position with the positioning support cushion as pleasant, whereas only 46% of patients were pleased with the position without cushion. CONCLUSION: The positioning support cushion designed in our department makes a substantial contribution to quality assurance in breast irradiation. It significantly increases the patients' comfort in a supine position. In contrast to conventional positioning and fixation aids it may be quickly and easily applied at low costs. Therefore, its use can be recommended.

Bedding and Linens↗
PubMed1998

[Improved reproducibility and comfort by standardized postural support in the irradiation of the female breast].

BACKGROUND: Positioning and immobilisation techniques are essential for precise radiotherapy. The currently available standardised positioning devices are insufficient. For this reason, we designed a new and generally usable hard foam positioning support cushion for the breast irradiation and tested its usefulness in a prospective study. PATIENTS AND METHODS: Fifty-five female breast cancer patients receiving adjuvant radiotherapy following breast conservative surgery were irradiated either without immobilisation (n = 27) or with the developed positioning support cushion (n = 28). The time necessary for patient set-up, the subjective lying comfort and--comparing portal images with simulator images--the reproducibility of the set-up were determined. RESULTS: It was possible to improve irradiation reproducibility significantly (average deviation without positioning support cushion: 8.4 mm, with positioning support cushion: 6.1 mm, p < 0.001). The additional time required for the positioning of the patient was in average 19 s (with positioning support cushion: 74 s, without cushion: 55 s). A significantly higher proportion of patients (72%) found the position with the hard foam cushion was pleasant, whereas only 46% of patients were pleased with the position without cushion. CONCLUSION: The positioning support cushion designed in our department seems to play an important role in quality assurance of external beam irradiation of the breast and significantly increases the patients' comfort in a supine position. Compared to conventional positioning and fixation devices it may be quickly and easily applied at low cost. Therefore, its use can be recommended.

Aged↗
PubMed1997

[Which factors modify the reproducibility of patient positioning in the daily irradiation routine?].

AIM: Factors which influence the accuracy of the field application during daily irradiation routine are not well known. The aim of this prospective analysis was to determine the significance of these factors on the occurrence of field misadjustments in irradiation without immobilization and to evaluate their clinical relevance. PATIENTS AND METHODS: Fifty-three patients received external cobalt-60 beam irradiation without fixation. Once weekly portal images of all treatment fields were carried out. In addition to objective patient data (age, weight, height, general condition, irradiation indication), the psychological situation of the patient during treatment (anxiety, restlessness, pain) and work circumstances of the medical staff during treatment were evaluated once weekly. The distance of clearly visible anatomic structures to the field borders of the portal images were measured and the deviation to the corresponding simulator images was calculated. Patient data were correlated to the number of field misadjustments (deviation larger than 1 cm). RESULTS: Patients whose condition is generally poor and patients being treated palliatively, patients with feeling of anxiety, restlessness or pain during simulation or irradiation and heavy patients (90 kg and more) were more often misadjusted. The number of field misadjustments increased with the stress of the medical staff. CONCLUSIONS: The problem of reproducibility of external beam irradiation without fixation in palliative treatment is of clinical relevance. Effective analgesic therapy and a comfortable and painfree patient set-up reduce misadjustments. In curative treatment, immobilization techniques should be used.

Aged↗
PubMed1997

Can prophylactic application of immunoglobulin decrease radiotherapy-induced oral mucositis?

Therapeutic application of immunoglobulin is reported to be successful in radiation-induced oral and oropharyngeal mucositis. In this study the efficacy of prophylactic application of immunoglobulin was investigated. In 42 patients with head and neck cancer, postoperative radiation treatment or radiation combined with chemotherapy was performed. In 20 consecutive patients, prophylactic mucositis treatment consisted of panthenol (4 x 10 ml/day) and nystatin (4 x 1 ml/day). The 22 following patients received, supplementary to panthenol and nystatin, 800 mg (5 ml) human immunoglobulin intramuscularly once weekly. During the treatment time, the degree of mucositis was examined 3 times a week. The distribution of maximal mucositis degree revealed slightly more severe mucous membrane reaction in the control group compared with the immunoglobulin group (n.s.). The analysis of mean mucositis degrees in both groups demonstrated statistically significant differences (t test, p = 0.031) related to the entire group (n = 42) and to those 16 patients receiving radiation combined with chemotherapy. There was no significant immunoglobulin-induced effect on mucositis in patients treated by radiation alone. The time from the beginning of therapy to the first interruption could be prolonged 5 days in the immunoglobulin group (n.s.). In conclusion, it is demonstrated that the prophylactic application of immunoglobulin seems to lower the degree of radiation-induced mucositis. In comparison to the published data about therapeutically given immunoglobulin, the clinical efficacy of the prophylactic application of immunoglobulin as it is performed in this study is less evident.

Adult↗
PubMed1997

Bilateral breast carcinoma versus unilateral disease. Review of 498 patients.

In literature data, an uncertainty exists whether occurrence of bilateral breast cancer decreases the survival probability of affected patients. Therefore, we analyzed the medical records of 498 postoperatively irradiated (1977-1982) female breast cancer patients (T1-4,N0-3,M0). In the follow-up time, in 36 patients a bilateral breast carcinoma treated by surgery with or without radiotherapy was found. The 10-year overall survival rates were 54% in patients who had unilateral disease, compared with 56% in bilateral carcinoma patients, respectively. The incidence of metastasis did not differ between both groups: 24.2% versus 38.8%. Eleven percent of unilateral cancers recurred; in the other group, local failure of the first and second tumor was observed in 19.4% and 11.1%, respectively. We conclude that the occurrence of bilateral breast cancer has no significant impact on survival, although the development of local failures and metastases seems to be more frequent. The therapeutic strategy in bilateral carcinoma should resemble the treatment procedure in unilaterally affected patients.

Adult↗
PubMed1996

Increase of surface dose using wound dressings during percutaneous radiotherapy with photons and electrons.

Different wound dressings are used for the supportive treatment of patients with radiation-induced skin lesions. Depending on beam quality and energy, an increase of the dose administered to the skin and thus an aggravated skin reaction is to be expected during percutaneous irradiation. The increase of the skin dose during irradiation with photons (Co60, 6 MV, 42 MV) and electrons (7 MeV, 20 MeV, 42 MeV) was determined using thermoluminescence dosimetry. The use of wound dressings during electron irradiation and during soft irradiation therapy does not significantly increase the dose administered to the skin and does not therefore cause any problems. During irradiation with high energy photons only extremely thin dressings should be used; if there is an aggravated skin reaction, the dressing should be taken off before irradiation commences.

Bandages↗
PubMed1996

In vivo dose increase in the presence of dental alloys during 60Co-gamma-ray therapy of the oral cavity.

During irradiation of the mouth cavity, dental metallic materials emit secondary electrons and thus increase the applied radiation dose in their vicinity. Therefore, local destruction of the mucous membrane contacting metallic dental crowns and fillings may be observed. Available data on this dose increase are based on measurements with beam arrangements perpendicular to the metallic surface. Since the dose modification depends on the beam direction in relation to specimen surface, a reliable prediction of dose modification in the close vicinity of dental caps on fillings under complex beam arrangements, as applied in the irradiation of head and neck region from the published data is not possible. Therefore, we measured dose increase in the immediate surrounding of metallic dental material using thermoluminescence dosimetry on the phantom and during routinely applied 60Co gamma ray therapy. Phantom measurements were carried out using several oblique irradiation angles and rotational therapy. In vivo measurements were carried out at alloy specimens containing gold, palladium, and amalgam in six patients and at permanently fixed golden teeth in five patients. In vivo, the following relative dose increase values according to a simultaneously measured reference value were obtained at the surface of different dental materials: 61% for fixed golden caps. 68% for the specimen containing gold, 33% for the specimen of palladium and 61% for the specimen of amalgam. The measured dose increases due to metallic dental material during routinely applied external 60Co beam irradiation are lower compared with those of perpendicular beam arrangements. Although, the extent of dose modification is less than expected, we still advocate protection of the oral mucosa to prevent painful lesion spots.

Cobalt Radioisotopes↗
PubMed1996

[Radiation load on the skin using a silicone-coated polyamide wound dressing during photon and electron radiotherapy].

BACKGROUND: Silicone-coated polyamide wound dressing is frequently used for the supportive treatment in patients with radiation induced skin lesions. The use of this kind of dressing during radiotherapy with high energy beams shifts the dose built-up effect towards the skin surface. Thus the dose delivered to the skin increases. The present work quantifies changes of the skin dose by a commercial silicon-coated polyamide wound dressing. The dependence on the beam quality and on different treatment techniques is investigated. PATIENTS AND METHODS: Measurements were performed with photon (60Co, 6 MV, 42 MV) and electron (7 MeV, 20 MeV, 40 MeV) beams using thin LiF thermoluminescence dosimeters (TLD) in a perspex phantom. The beams were directed perpendicularly to the phantom surface. For 60Co and 6 MV photon beams the skin dose was evaluated in vivo at different beam arrangements and at a given reference dose. RESULTS: For 60Co, 6 MV and 42 MV photon beams wound dressing caused a dose increase on the surface of the perspex phantom by a factor of 1.65, 1.39 and 1.33 respectively. Using oblique or rotational techniques for 60Co and 6 MV photon irradiation the wound dressing increased the skin dose but less compared to perpendicular beam direction. For electron beams the skin dose is relatively high (from 84% to 92%) and an increase by a dressing has no clinical relevance (factor 1.03 to 1.05). CONCLUSION: The silicone-coated polyamide wound dressing causes no relevant skin dose increase during radiation treatment with electron beams and can be left on the skin during irradiation. During radiation treatment with photon beams like 60Co and 6 MV the protective procedure should be adapted to skin changes, in case of strong skin reactions a removal during the time of irradiation should be considered.

Bandages↗
PubMed1996

Improvement of radiation treatment planning in squamous-cell head and neck cancer by immuno-SPECT.

UNLABELLED: Previous studies have shown high accuracy for immunoscintigraphy with 99mTc-MAb-174 in patients with squamous-cell carcinoma of the head and neck region compared to CT and MRI. We conducted a prospective study to determine if immunoscintigraphy provides additional diagnostic information for radiation treatment planning. METHODS: Radioimmunoscintigraphy (RIS) was performed on 40 patients (planar, whole-body, SPECT) with histologically confirmed squamous-cell carcinoma (30 primary tumors, 10 recurrences) after injection of the 99mTc (1.1 GBq) labeled monoclonal anti-squamous-cell cancer antibody 174H0.64 (murine IgG1). Results were combined with information obtained by clinical examination, sonography, panendoscopy and x-ray CT. The strategy for radiation treatment and the required treatment volumes were defined with and without immunoscintigraphical findings. RESULTS: Additional diagnostically relevant information from RIS was obtained from 10 patients (25%) with advanced tumors or recurrences. In three patients (7.5%), the treatment volume had to be extended. The therapeutic strategy for seven patients (17.5%) had to be changed due to the detection of metastatic disease beyond the head and neck region. RIS of patients with squamous-cell cancers of the head and neck region with 99mTcMAb-174H0.64 enabled the detection of tumors that were not depicted by other conventional diagnostic imaging procedures. CONCLUSION: The use of RIS in radiation treatment planning of advanced tumors of the head and neck region appears to yield important diagnostic information that may alter patient management.

Carcinoma, Squamous Cell↗
PubMed1995

[The in-vivo determination of dosage intensification due to dental alloys in the therapeutic irradiation of the oral cavity].

BACKGROUND: In the course of therapeutic irradiation of regions in the mouth cavity dosage increase due to the emission of secondary electrons in the vicinity of dental materials can be observed. This could induce local destruction of the mucous membrane in contact with metallic dental crowns and fillings. As at now, only rough estimates of this dosage increase could be made with the help of measurements carried out with models. PATIENTS AND METHODS: The degree of dosage increase in the immediate surrounding of metallic dental material was measured in an in-vivo study during therapeutic irradiation with 60Co gamma rays in the area of mouth cavity of 11 patients. Measurements were carried out by thermoluminescent dosimetry at permanently fixed golden teeth and alloy specimens containing gold and palladium and amalgam. RESULTS: The following relative dosage values according to a simultaneously measured reference value were measured at the surface of the different dental materials: 161% near fixed golden caps, 168% near the specimen containing gold in a high percentage, 133% near the specimen of palladium and 161% near the specimen of amalgam. CONCLUSION: The in vivo measured dosage increases due to metallic dental prosthesis are less than values obtained using back scatter arrangements for irradiating phantoms. Despite this, they could be of clinical relevance. Thus the usage of a mucous membrane protection during irradiation with 60Co, as a means of preventing local lesions of the oral mucosa, due to dental alloys within the treatment volume remains inevitable.

Cobalt Radioisotopes↗
PubMed1995

[Immunoglobulin for prevention of radiogenic mucositis].

Among various therapies administered during radiation-induced mucositis, treatment with immunoglobulin has proven clinically successful. In this study the efficacy of prophylactic applications of immunoglobulin was investigated from January 1992 through August 1993. Forty-two patients with histologically-proven head and neck cancer were given postoperative radiation treatment. In cases with macroscopic tumor residues or inoperability, combined radio-chemotherapy was given. This included 51.3 Gy at 1.9 Gy 5x/week, boosted to 10-26 Gy at 2 Gy 5x/week and carboplatin 60 mg/m2 at days 1-5 and 29-33. Panthenol (4x10 ml/day) and nystatin (4 x 1 ml/day) were given to 20 patients as prophylactic treatment for mucositis. Twenty-two subsequent patients also received intramuscular 800 mg (5 ml) human immunoglobulin (1x/week). According to the Seegenschmiedt/Sauer classification the extent of mucositis was determined 3x/week. Comparison of the distribution of maximal mucositis revealed a slightly more severe mucosal reaction in the control group (n.s.). Analysis of the mean degree of mucositis in both groups demonstrated statistically significant differences (p = 0.031) related to the whole collective and patients receiving concomitant chemotherapy while no effect of immunoglobulin was found in patients treated by radiation alone. In the immunoglobulin-treated-group, the time from the beginning of therapy to the first interruption was prolonged 5 days (37.5 +/- 13.1 vs. 42.7 +/- 13.3 days), but this difference was not significant. Although prophylactic application of immunoglobulin seemed to lower the degree of radiation-induced mucositis, this effect was less significant when compared to the immunoglobulin given in a therapeutic manner.

Adult↗
PubMed1995

[The prognosis of bilateral breast carcinoma compared to unilateral breast tumor. 5- and 10-year follow-ups].

PURPOSE: A review of published data does not provide a certainty whether survival rates are comparable or worse in women with bilateral breast cancer versus patients with an unilateral tumor. Therefore results of therapy in one-sided and both-sided breast cancer were retrospectively analysed. PATIENTS AND METHODS: In a period from 1977 to 1982 (follow-up 5 to 12 years) 531 breast cancer patients with T1-4 N0-3 M0 tumors were treated with mastectomy (n = 416) and breast conserving therapy (n = 115). Postoperative radiotherapy was performed in all patients (50 Gy, 2 Gy/day 5 times/weekly; chest wall/breast and regional lymph nodes). Patients with positive lymph nodes received chemotherapy. Forty patients developed bilateral breast cancer (simultaneous n = 10, metachronous n = 30) that was treated by mastectomy (n = 28) and conservative surgery (n = 12), respectively, followed by radiotherapy in 26 women. RESULTS: Five- and 10-year survival was 74% and 56% in unilateral affected women. In 83% and 67% there were no metastases, respectively. Incidence of metastases was 27.9%. In bilateral breast cancer group survival rates were 85% and 59% and without evidence of metastases 87% and 60%, respectively. Distant disease was diagnosed in 35%. Differences between the 2 groups were statistically not significant. Whereas in time of follow-up 11% of unilateral cancer locally failed in bilateral cancer patients recurrences of the first and second tumor were seen in 20% and 10%, respectively. CONCLUSIONS: Survival of patients with bilateral breast cancer is not significantly decreased compared with unilateral disease although in patients with both-sided carcinoma local recurrences and metastases seem to occur more frequently.

Adult↗
PubMed1995

[Value of SPECT-immunoscintigraphy in radiation treatment planning for patients with squamous cell carcinomas in the head and neck area].

PURPOSE: Introduction of monoclonal antibodies (immunoscintigraphy) has significantly extended the diagnostic spectrum of nuclear medicine in oncology. The detection rate of this new method in patients bearing squamous cell carcinoma of head and neck is better compared to computed tomography and magnetic resonance imaging. In a prospective study, we examined whether immunoscintigraphy in addition to other imaging procedures is able to provide additional diagnostic information for radiation treatment planning.

Antibodies, Monoclonal↗
PubMed1995

[The value of conventionally fractionated radiotherapy in the local treatment of HIV-related Kaposi's sarcoma].

BACKGROUND: During the course of AIDS, 25 to 44% of homosexual patients infected with the human immunodeficiency virus develop Kaposi's sarcoma. Main manifestation is the skin. Response rates of 80 to 100% can be achieved with total dosage up to 50 Gy. Nevertheless, remissions can also be attained with 20 Gy of fractionated radiotherapy. As clinical data on low dose conventional fractionated radiotherapy are insufficient we analysed the response rates of an overall dose of 20 Gy in conventional fractionation. PATIENTS AND METHODS: From June 1991 to June 1993, 43 patients with 111 HIV-associated Kaposi's sarcoma of the skin or oral cavity were treated. Lesions were irradiated with 5 to 12 MeV electrons or 60Co gamma-rays. The fractionation scheme was 5 times 2 Gy/week for skin and endoral lesions with a total reference dosage of up to 20 Gy. Side effects were assessed during therapy and the therapeutic result 6 weeks after end of treatment. RESULTS: Thirty-eight out of 111 lesions were judged as complete response (CR) (34%), 61/111 as partial response (PR) (55%) and 12/111 were judged as no change (NC) (11%). Overall response (CR + PR) was 89%. Two patients with lesions of oral cavity suffered from RTOG grade-IV mucositis after 10 and 14 Gy. In 71/106 skin lesions (67%), radiation induced RTOG grade-1 reactions were observed. CONCLUSION: In patients with HIV associated Kaposi's sarcoma effective palliation can be achieved by means of radiotherapy with an overall dose of 20 Gy in conventional fractionation. Yet, the fraction of patients with complete responses is with 34 to 47% lower compared with doses above 20 Gy (66 to 100%). With reference to the reported data our results point to a dose-response relationship for Kaposi's sarcoma. Therefore higher total reference doses, e.g. 30 Gy with weekly 5 times 2 Gy or 24 Gy with 5 times 1.6 Gy for mucous lesions, respectively, are suggested as by this mean the complete response rate can be doubled.

Adult↗