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Biomedical subjects

N R Datta

Publications and source records attributed to N R Datta.

14 recordsLinked to original sources
PubMed1997

Midline shield for radiation therapy of carcinoma of the uterine cervix: should it be "midline" or "individualized".

This study attempts to evaluate the advantage of individualized midline shield (IMLS) constructed on the basis of uterine geometry and applicator position in terms of the dosimetric consequences to points A-right (AR) and left (AL) as compared to standard midline shield (SMLS) in radiation therapy of carcinoma cervix. Twenty consecutive patients of carcinoma cervix (Stage I, II and III) were treated by external beam radiotherapy (EBRT) (50 Gy/5 weeks/25 fractions) and high-dose rate intracavitary brachytherapy (24 Gy/4 weeks/4 fractions) prescribed at point A. At the completion of 40 Gy by EBRT (phase I), IMLS (5 cm wide) at isocenter was fabricated on the basis of uterine geometry as ascertained by a dummy intracavitary application. The remaining 10 Gy of EBRT was delivered using IMLS (phase II) to effectively minimize and optimize the dose to point A. The dose profiles of IMLS were compared against the corresponding dose profile of a 5 cm SMLS and were found to be dependent on the positional variation of AR and AL with respect to the midline. With IMLS, the dose to AR and AL for the 10 Gy of phase II varied between 21.7-38.87% (30.01 +/- 4.87) and 22.42-35.72% (28.12 +/- 3.79) respectively. However with SMLS, the AR and AL doses would have ranged from 22.03% to 77.26% (34.55 +/- 15.94) for AR and from 20.59% to 96.2% (46.93 +/- 28.15) for AL leading to considerable inhomogeneity. Thus, in protocols incorporating midline shield for radiotherapy of carcinoma cervix, IMLS in place of SMLS could be preferred for achieving a definitive and homogeneous dose to the points AR and AL.

Brachytherapy↗
PubMed1996

Spatial information on dose distribution using multisectional dose-volume histograms.

Dose-volume histograms are useful tools to summarize the information on the dose profiles resulting within a target volume. However, the spatial relationships of the hot and the cold spots are blunted in the dose-volume histograms. This study tries to circumvent this problem using multisectional dose-volume histograms and highlight the utility of these in the optimization of a radiation therapy plan.

Brachytherapy↗
PubMed1996

Feasibility of non-cisplatin-based induction chemotherapy and concurrent chemoradiotherapy in advanced head and neck cancer.

The purpose of the present study was to determine the safety and efficacy of induction chemotherapy followed by concomitant chemoradiotherapy. Thirty-eight patients were randomised to receive induction chemotherapy, consisting of cyclophosphamide and methotrexate followed by concomitant 5-fluorouracil and irradiation (study group) or irradiation alone (control group). There were non-significant differences in the initial tumor clearance rates in the two groups. Median disease-free survival (in complete responders) was 17 months (6-60+) vs 11 months (5-60+) (p = 0.407) and overall survival 11 months (1-60+) vs 14 months (2-60+) (p = 0.428) in the study and control groups respectively. Acute morbidity and deaths during intervention were higher in the study group (p = 0.007). This study suggests that induction along with concomitant chemoradiotherapy is too toxic for routine use and also fails to provide a survival benefit.

Adult↗
PubMed1995

Urinary tract infection in patients of gynecological malignancies undergoing external pelvic radiotherapy.

A total of 216 midstream urine (MSU) samples from 36 patients with gynecological malignancies undergoing external pelvic radiotherapy (RT) were studied periodically every week for any evidence of urinary tract infection (UTI). UTI was detected in 33.3% patients of whom 8.3% had infection at the onset of RT and the rest developed UTI during the course of therapy. All three patients who had UTI at the onset of RT underwent cystoscopy as a part of routine pretreatment workup. A higher preponderance of UTI was observed in patients of stage III carcinoma cervix (33.3%) compared to stage II (16.7%) during the course of RT. Half of the patients with UTI had repeated episodes of infection despite appropriate antibiotic treatment. The study emphasizes the importance of conducting periodic MSU examination in patients with gynecological malignancies during RT and its treatment with appropriate antibiotics to minimize the risks of further injury to the already susceptible uroepithelium following radiotherapy.

Adult↗
PubMed1995

Multisectional planning for external beam radiotherapy: a "poor person's" alternative to three-dimensional treatment planning.

Recent technical advances in the field of computers have led to the use of three-dimensional dose computation for optimizing a radiation therapy plan. However, in centers which lack such a state-of-the-art technology, one could explore the use of multisectional planning to obtain information about the dose profiles all along the target volume. This article highlights the utility of multisectional planning as an alternative to three-dimensional treatment planning systems for external beam radiation therapy.

Esophageal Neoplasms↗
PubMed1993

Actinomycosis mimicking carcinoma of the maxillary sinus.

Human actinomycosis may pose a diagnostic problem at times and is often mistaken for a neoplasm. A thirty-five year old male was clinically diagnosed as a case of carcinoma of the right maxillary sinus on the basis of history, clinical presentation and radiologic findings. Tissue biopsy was negative for malignancy on three consecutive occasions. Microscopic examination showed bits of granulation tissue and fragments of filamentous structures. On microbiological examination, Actinomyces israelii was isolated and fungus culture was negative. Long term Penicillin treatment caused disappearance of all signs and symptoms. The report highlights the importance of bearing in mind the fact that certain rare, chronic, suppurative granulomatous infections, like actinomycosis, may mimic malignancy.

Actinomycosis, Cervicofacial↗
PubMed1991

Giant cell tumour of the petrous bone.

Giant cell tumours (GCT) are rare in the skull bones. In the cranium the sphenoid bone is the most common site. The petrous bone is a very uncommon location for such tumours. The chance location of GCT at the base of the skull makes total surgery difficult and hazardous. A case of GCT of the petrous bone is presented. The clinical course in the patient and role of primary radiotherapy in GCT in such an unusual site is discussed.

Adult↗
PubMed1990

Evaluation of electron beam irradiation technique in Indian breast carcinoma patients.

A technique for post-mastectomy irradiation in breast cancer patients is described. The chest wall and internal mammary nodes are irradiated with single, anterior electron beam. The axillary and supraclavicular nodal regions are treated with parallel opposed telecobalt beams. A total of 124 patients have been subjected to this procedure. All, except five, completed the treatment. Desquamation, dry as well as wet, was of universal occurrence in electron irradiated zones. The follow up period is 2-26 months with a median of 12 months. Out of the 106 followed up patients, two developed local recurrence while distant metastases were observed in 13 patients.

Adult↗
PubMedDate not supplied

Head and neck cancers: results of thermoradiotherapy versus radiotherapy.

Sixty-five patients were included in a randomized clinical study to evaluate the efficacy of local hyperthermia as a concomitant agent to radiotherapy in the treatment of carcinoma of the head and neck region. Local hyperthermia at 42-43 degrees C was generated by a 27 x 12 MHz radiofrequency diathermy unit and was used before radiotherapy in 33 patients; the remaining 32 patients were subjected to radiotherapy alone. The response in patients with early lesions (Stage I and II) was similar for both the groups, while in patients with advanced disease (Stage III and IV) a significantly better tumour control was obtained by the use of the combined treatment.

Carcinoma, Squamous Cell↗