TRACE METALS IN CANCER PATIENTS AND THEIR CORRELATION WITH RENAL FUNCTION

ABSTRACTTwo trace elements, copper (Cu) and zinc (Zn) in serum are elevated in cancer patients since both areconstituents of super oxide dismutase (SOD) as metalloenzyme, the enzyme that scavenge free radicals andactivated oxygen species in the body. The study of 52 cancer patients comprising of 31 carcinoma stomachand 21 breast cancer showed the elevation of both of these trace elements in serum when compared to 32healthy controls and effected the kidney functions as a consequences. Serum Cu and Zn were estimated byAtomic Absorption Spectrometer (AAS), analyzed statistically by student "t" test and marked elevationwas observed in cancer patient compared to healthy controls. Serum Cu and Zn values were 98.13 ± 17.49μg/dl 99..57 ± 13.91 μg /dl respectively in 38 healthy subjects and these trace metals were 156.23 ± 31.02 μg/dl and 171.86 ± 35.15 μg/dl in 52 cancer patients showing significant elevation (P <0.001). These elevatedelements were routed through kidneys and damaged nephrons since both of them are cationic heavy metals.Nephrotoxicity of these trace metals was reflected as elevated level of blood urea and creatinine and werefound to be 27.44 ± 7.72 mg /dl and 0.83 ± 0.30 mg/dl in control groups and 64.49 ± 49 mg /dl and 1.60 ± 0.72mg/dl in cancer patients respectively, a significant elevation (P<0.001) in study group. The elevation ofthese parameters may indicate renal origin.Key Words: Serum copper, serum zinc, super oxide dismutase, carcinoma stomach, carcinoma breastand nephrotoxicity.

Awareness of diagnosis and psychiatric morbidity among cancer patients--a study from South India

Awareness regarding cancer diagnosis and its relationship to psychiatric morbidity was studied in 294 newly admitted cancer patients at an oncology center in South India. Fifty-four percent of patients were aware that they had cancer and were able to discuss their diagnosis; 46% of patients reported nonawareness of diagnosis. Discriminant function analysis revealed that oral cancers and relatives' awareness of the cancer was more prevalent in the group aware of diagnosis. More patients in the "unaware" group refused treatment for psychological distress. There was no difference between the two groups in patterns and prevalence of psychiatric morbidity. The study emphasizes the complexities in assessing awareness in cancer patients and a need to study its various components and relationship to psychological distress.

Psychological well-being among cancer patients receiving radiotherapy--a prospective study

The impact of cancer on the psychological well-being of newly diagnosed cancer patients before and during the course of radiotherapy was assessed in 70 consecutive cancer patients. Most of the patients were over 40 years of age, women, illiterate and from a lower socioeconomic group. During the course of treatment there was a decrease in the well-being scores on some dimensions such as perceived family and primary group support. Improvements were seen in the dimensions of positive feelings, coping, social support other than the family and spiritual well-being. There were no changes in the dimensions of negative feelings and perceived ill-health. The results give a profile on well-being and the changes observed during radiotherapy.

Sacral chordomas: a 10-year study

A retrospective analysis of 14 cases of sacral chordoma seen between 1984 and 1993 at the Kidwai Memorial Institute of Oncology is reported. The mean patient age was 54 years, with 13 males and one female. Seventy-one per cent of patients presented with symptoms related to a painful sacral mass. Eight patients underwent radical surgery and two had adjuvant radiotherapy. One patient had a partial tumour resection. Three patients received radical radiotherapy. Two patients were offered only pain relief medication. The median follow-up was 33 months. The actuarial overall survival (OS) at 5 years was 48%. In the 12 patients in whom curative therapy was attempted, the 5-year OS was 56% and progression-free survival was 36%. Four patients developed local recurrence and three developed distant metastasis.

Dysgerminoma of the ovary: a retrospective study

A retrospective analysis of 22 patients with ovarian dysgerminoma who were treated between 1980 and 1987 was carried out. The median age at presentation was 24.5 years. A total of 15 patients were in stage I, one patient was in stage II and six patients were in stage III. Bilateral ovarian involvement was present in four patients. Conservative surgery was carried out in nine patients and 11 patients underwent radical surgery. Two patients had biopsy only. Fourteen patients received adjuvant radiotherapy and three patients received salvage radiation for recurrent disease. The 10-year actuarial survival rate was 81.8%. All 15 patients in stage I were alive and disease-free at a median follow-up of 125 months. Four patients (one in stage II and three in stage III) died of progressive or recurrent abdominopelvic disease. Pelvic recurrence occurred after conservative surgery in two patients in stage IA who had a tumour size greater than 10 cm, but they were salvaged with radical surgery, chemotherapy and radiotherapy. There were seven patients aged 20 years or less. All were alive and disease-free at a median follow-up of 127 months.

Efficacy and safety of granulocyte macrophage-colony stimulating factor (GM-CSF) on the frequency and severity of radiation mucositis in patients with head and neck carcinoma

PURPOSE

Based on the clinical evidence of mucosal protection by GM-CSF during cytotoxic chemotherapy, a pilot study was undertaken to determine the safety and mucosal reaction of patients receiving GM-CSF while undergoing definitive conventional fractionated radiotherapy in head and neck carcinoma.

METHODS AND MATERIALS

Patients were considered eligible if buccal mucosa and oropharynx were included in the teleradiation field. Ten adult patients with squamous cell carcinoma of head and neck (buccal mucosa--8 and posterior 1/3 tongue--2) were entered into the trial. Radiation therapy was delivered with telecobalt machine at conventional 2 Gy fraction and 5 fractions/week. The radiation portals consisted of two parallel opposing lateral fields. GM-CSF was given subcutaneously at a dose of 1 microg/kg body weight, daily, after 20 Gy until the completion of radiation therapy. Patients were evaluated daily for mucosal reaction, pain, and functional impairment.

RESULTS

The median radiation dose was 66 Gy. Eight patients received > or = 60 Gy. The tolerance to GM-CSF was good. All 10 patients completed the planned daily dose of GM-CSF without interruption. Mucosal toxicity was Grade I in four patients till the completion of radiotherapy (dose range 50-66 Gy). Six patients developed Grade II reaction, fibrinous mucosal lesions of maximum size 1.0-1.5 cm, during radiotherapy. None developed Grade III mucositis. The maximum mucosal pain was Grade I during GM-CSF therapy. In two patients after starting GM-CSF the pain reduced in intensity. Functional impairment was mild to moderate. All patients were able to maintain adequate oral intake during the treatment period. Total regression of mucosal reaction occured within 8 days following completion of radiotherapy.

CONCLUSIONS

GM-CSF administration concurrently with conventional fractionated radiotherapy was feasible without significant toxicity. The acute side effects of radiotherapy namely mucositis, pain, and functional impairment were nil to minimal. The results are suggestive of mucosal protection by GM-CSF during radiotherapy and warrants further study in randomized double blind trial.

Extrapolated response dose as a potential tool in radiotherapy and chemo-radiotherapy of head and neck cancers

An analysis of head and neck cancer patients treated by radiotherapy (RT) alone (114 patients) and by chemo-radiotherapy (RT + CT) (115 patients) was carried out; the doses varied from 40-77 Gy and 35-71 Gy in RT and RT + CT groups respectively. The chemotherapy (CT) (induction/concurrent) drugs used were 5-FU, cisplatin, methotrexate either single or in combination. Extrapolated response dose values were evaluated with alpha/beta values of 10, 2.5 and 6 Gy for acute, late complications and tumour response, respectively. Dose enhancement factor (DEF) and Therapeutic gain factor (TGF) values were evaluated on the basis of ERD for patients receiving 5-FU RTCT (72 patients). ERD vs late complication rate and response rate curves were drawn for RT, RT + CT (< 7 cycles), RT + CT (> 6 cycles) and RT + CT (cumulative). DEF values for response rate were 0.95, 0.95 and 0.82 for the three RT + CT groups respectively. Similarly DEF values for late complication rate were evaluated as 0.87, 0.93 and 0.88. TGF values for RT + CT were 1.09, 1.02 and 0.93. TGF values indicated lack of significant influence of CT on clinical outcome. The correlation of ERD with late complication, response and status at last follow up (NED) was statistically significant for both groups (P < 0.01). ERD did not correlated with acute complication in RT group (P > 0.01). From the present analysis, in RT + CT treatments of head and neck cancers, an ERD value of 69 Gy is suggested as the limit for an acceptable 5% late complication rate.

Descriptive epidemiology of childhood cancers in Bangalore, India

While fairly complete and reliable incident data on childhood cancers are available from the registries in India, mortality and survival information is not. Information concerning the latter was obtained by the Bangalore cancer registry through active follow-up involving visits to homes of patients. Between 1982 and 1989, 617 cases of cancers in childhood were registered, giving an age-standardized incidence rate of 84.8 and 48.4 per million in male and female children, respectively. Active follow-up provided mortality/survival information in 532 or 86.2 percent of these cases. Overall, observed five-year survival was 36.8 percent (both genders combined) with a relative survival of 37.5 percent when childhood mortality in the general population was taken into account. The five-year relative survival was best for thyroid carcinoma (100 percent) followed by Hodgkin's disease (73 percent) and retinoblastoma (72.9 percent). Survival was comparatively low, being 9.9 percent in acute nonlymphatic leukemia and less than 20 percent in rhabdomyosarcoma and the category grouped as 'other malignant neoplasms.' Survival in Hodgkin's disease was influenced by clinical stage at presentation, but was not statistically significant possibly due to small numbers.

Importance of anatomical subsite in correlating risk factors in cancer of the oesophagus--report of a case--control study

In Bangalore, cancer of the oesophagus is the third most common cancer in males and fourth most common in females with average annual age-adjusted incidence rates of 8.2 and 8.9 per 100,000 respectively. A case-control investigation of cancer of the oesophagus was conducted based on the Population-based cancer registry, Bangalore, India. Three hundred and forty-three cases of cancer of the oesophagus were age and sex matched with twice the number of controls from the same area, but with no evidence of cancer. Chewing with or without tobacco was a significant risk factor. In both sexes chewing was not a risk factor for cancer of the upper third of the oesophagus. Among males, non-tobacco chewing was a significant risk factor for the middle third but not for the other two segments and tobacco chewing was a significant risk factor for the lower third of the oesophagus, but not for the other two segments. Bidi smoking in males was a significant risk factor for all three segments being highest for the upper third, less for the middle third and still less for the lower third. The risk of oesophageal cancer associated with alcohol drinking was significant only for the middle third.

Improving cancer radiotherapy with 2-deoxy-D-glucose: phase I/II clinical trials on human cerebral gliomas

PURPOSE

Evaluation of tolerance, toxicity, and feasibility of combining large fraction (5 Gy) radiotherapy with 2-deoxy-D-glucose (2DG), an inhibitor of glucose transport and glycolysis, which has been shown to differentially inhibit repair of radiation damage in cancer cells.

METHODS AND MATERIALS

Twenty patients with supratentorial glioma (Grade 3/4), following surgery were treated with four weekly fractions of oral 2DG (200 mg/kg body weight) followed by whole brain irradiation (5 Gy). Two weeks later, supplement focal radiation to the tumor (14 Gy/7 fractions) was given. Routine clinical evaluation, x-ray computerized tomography (CT), and magnetic resonance (MR) imaging were carried out to study the acute and late radiation effects.

RESULTS

All the 20 patients completed the treatment without any interruption. The vital parameters were within normal limits during the treatment. None reported headache during the treatment. Mild to moderate nausea and vomiting were observed during the days of combined therapy (2DG + RT) in 10 patients. No significant deterioration of the neurological status was observed during the treatment period. Seven patients were alive at 63, 43, 36, 28, 27, 19, and 18 months of follow-up. In these patients, the clinical and MR imaging studies did not reveal any late radiation effects.

CONCLUSIONS

Feasibility of administering the treatment (2DG + 5 Gy) is demonstrated by the excellent tolerance observed in all 20 patients. Further, the clinical and MR studies also show the absence of any brain parenchymal damage.

Serum vitamins' status in oral leucoplakias--a preliminary study

Vitamins, such as A, beta carotene, C, E, B12 and folate, are the micronutrients with the strongest evidence of having a link to cancer prevention and control. Deficiency of these vitamins at the dietary, systemic or mucosal level will interact with tobacco use and increase the risk of oral precancerous lesions. The objective of this study was to (1) establish the baseline circulating levels of these vitamins in our normal population with and without tobacco use and (2) compare these levels with the values obtained in cases of oral leucoplakias. 50 normal controls with 25 each in chewers and non-chewers, matched for age and sex, were selected. 50 cases of oral leucoplakias (clinically detectable white patches) from the field constituted the study group. Simultaneous measurement of serum vitamin B12 and folate were carried out by radioassay. The other serum vitamins were estimated spectrophotometrically. Except for serum vitamin E, all the other serum vitamin levels were significantly decreased in oral leucoplakias compared to the controls. Cancer chemopreventive agents acting as inhibitors of both initiation and promotion, as analysed in our population, is promising for further intervention trials.

A case-control investigation on cancer of the ovary in Bangalore, India

Cancer of the ovary is the sixth leading cancer among females in Bangalore, and is a leading site of cancer in other population-based cancer registries in India. A case-control investigation was conducted utilizing the data from the population-based cancer registry in Bangalore. In addition to the core patient information, certain other details pertaining to consumption of tobacco, reproductive and obstetric factors and those related to the practice of family planning, including the method adopted, were available with the registry, for the period 1982-1985. Identical information was also available for patients residing in the registry area who did not have cancer. Ninety-seven cases of ovarian cancer in ever-married women were age-matched with 194 controls from the same area who showed no evidence of cancer. The risk of ovarian cancer was not influenced by tobacco habits, alcohol consumption, diet or the various reproductive factors. However, tubectomy as a method of family planning appeared to reduce the risk of development of ovarian cancer. This reduction in risk was not influenced by parity or age of the woman at the time of birth of the first child.

Descriptive epidemiology of lymphoid and haemopoietic malignancies in Bangalore, India

Lymphoid and haemopoietic malignancies as a group constitute one of the important cancers in India, as elsewhere in the world. While information on incidence and mortality of these cancers, and that on survival, are available from most developed countries, there are very few reports describing this experience in developing ones. Population-based cancer registration commenced in Bangalore, India, in January 1982, under the auspices of the Indian Council of Medical Research. This source provides fairly complete and reliable incidence data, but, in order to obtain mortality and survival information, active follow-up involving visits of homes of patients was undertaken. Between 1982 and 1989, 1397 cases of lymphoid and haemopoietic malignancies were registered in the Bangalore cancer registry, giving an age-adjusted incidence rate of 7.7 and 4.8 per 100,000 in males and females respectively. Active follow-up provided mortality/survival information in 1267 or 90.7% of these cases. The overall observed 5-year survival for these cancers combined (both sexes) was 26%, and relative survival 28.4%. The 5-year survival rate was lower in all the individual lymphomas and leukaemias as compared with similar reports from the developed countries. Survival in Hodgkin's disease was influenced by clinical stage and age at presentation.

Spinal cord compression by primary non-Hodgkin's lymphoma

Epidural Cord Compression (ECC) by primary lymphomas is rare entity and constitutes less than 3% of total malignant lymphoma with Non-Hodgkin's Lymphoma (NHL), diffuse large cell type being the most common histological subtype. In this paper 16 cases of primary NHL with cord compression seen at the Department of Medical Oncology, during the period 1988-1990 are reviewed. At presentation all patients had undergone Laminectomy with decompression of epidural mass. The histological diagnosis of NHL was subclassified according to the International working formulation and was evaluated for disease process elsewhere in the body. All patients with ECC by lymphoma received high dose steroids with concurrent Radiotherapy (local) and combination Chemotherapy. These patients had longer duration of neurological deficit prior to treatment had poor response. After 6 courses of chemotherapy 50% of the patients had complete neurological recovery (CR), 31% had partial neurological recovery (PR) and in 19% there was no neurological recovery (NR).

Incidence, mortality and survival in cancer of the cervix in Bangalore, India

Cancer of the cervix is the most common cancer among women in India, constituting between one-sixth to one-half of all female cancers with an age-adjusted incidence rate ranging from 19.4 to 43.5 per 100,000 in the registries under the National Cancer Registry Programme (NCRP) (Annual Reports, NCRP, ICMR). It has been estimated that 100,000 new cases of cancer of the cervix occur in India every year, and 70% or more of these are Stage III or higher at diagnosis. However, the incidence of cancer of the cervix as suggested in this report appears to be on the decline in Bangalore. Besides incidence and clinical stage at presentation knowledge of survival is essential to complete the picture of establishing baseline indicators to monitor and evaluate cancer control programmes. Survival analysis was carried out in 2121 patients diagnosed during 1982-89 in the population of Bangalore, India. The observed 5 year survival was 34.4% and the relative survival 38.3%. Clinical stage at presentation was the single most important variable in predicting survival. The 5 year observed survival for stage I disease was 63.3%, for stage II 44.0%, for stage III 30.3% and for stage IV 5.7%.

Survival in breast cancer: a population-based study in Bangalore, India

Survival from cancer reflects the aggressiveness of the disease, the effectiveness of treatment and host factors such as age. While hospital-based survival rates are typically used to evaluate the care provided in a particular hospital, population-based survival reflects the effectiveness of the overall cancer control strategy in the region. Here, we report the survival experience of 1514 breast cancer patients registered by the Bangalore population-based registry during 1982-1989. There have been very few reports on survival from cancer in India, mainly because of poor patient follow-up and inadequate system of registration of death. This has been largely overcome in this study by means of active follow-up through visits of homes of patients. Scrutiny of medical records and matching with death certificates, was also carried out in a small proportion (12%) of cases. Thus, information on vital status (whether dead or alive) as on January 1, 1993 was available for 1334 (88%) subjects and partial follow up data were available for a further 34 (2%). The observed 5 year survival was 42.3% and the corresponding relative survival was 46.8%. The observed survival was 57.4% for localized disease, 45.8% for direct extension, 37% for those with regional node involvement, 14.2% for distant metastasis and 38.3% for those with unstaged disease. The clinical extent of disease and the educational status were independent predictors of survival.

Efficacy of an anti-tobacco community education program in India

In a study on 'Assessment of Efficacy of an Anti-Tobacco Community Education Program' on Kolar District of Karnataka, India, an experimental and two control areas were chosen based on comparable population, health, and socioeconomic parameters. The two main objectives were to prevent individuals from taking up the tobacco habit among those who currently did not smoke or chew tobacco, and to stop the tobacco habit in those who did smoke or chew tobacco. A baseline tobacco-habit survey of the population was followed by anti-tobacco education of the community in the experimental area only. Two years later, a repeat survey of the population was conducted, followed by a final survey after a further three years. Methods of health education of the community included screening of films, exhibits, and personal contact with a display of photographs of the harmful effects of tobacco. The results were evaluated through changes in prevalence rates, quitters' rates, and initiation rate. The final survey showed that in the experimental area, the decline in the prevalence rate in the combined sample compared with the baseline rates was 10.2 percent in males and 16.3 percent in females, with a corresponding quitter's rate of 26.5 percent in males and 36.7 percent in females. Among men, a higher proportion (30.2 percent) had given up chewing compared with smoking (20.4 percent).

Physical characteristics of photon and electron beams from a dual energy linear accelerator

Clinically pertinent data of the photon beams of nominal energy 6 MV and 18 MV from a dual photon energy linear accelerator are measured using a radiation field analyser with semiconductor diodes and ionisation chambers. Percentage depth dose values are compared with available data from other linacs and BJR-17. Measurements made in the buildup region using a parallel plate chamber show a marked increase in the surface dose and dmax shifts by 3 mm and 14 mm for 6 MV and 18 MV photons, respectively as the field size is increased from 4 x 4 cm2 to the maximum. Variations of wedge angles with energy and field size are also determined up to wedge widths of 15 cm for all the four available wedge angles. Isodose plots of both the energies are plotted using semiconductor diodes in a RFA-3 system. Output factors, wedge transmission factors, and shielding tray factors were also measured in clear polystyrene phantom for both the photon energies at the depths of maximum ionisation. Beam characteristics of the electron beams of energies 6, 9, 12, 16, and 20 MeV produced by the Clinac-1800 have also been studied. The characteristics include percentage depth dose, isodose distribution, depth of maximum dose, surface dose, photon contamination, uniformity index, and penumbra. Most of the measurements were carried out using semiconductor detectors, whereas small volume ionization chambers and a plane-parallel chamber were kept as standards for comparison. Isodose distributions were drawn from the film densitometry method. Range-energy parameters are obtained from the observed depth dose data. These parameters vary from machine to machine and must be ascertained for individual units. The parameters differ to a considerable extent from their theoretically predicted values but generally follow the trend, experimentally observed by others, for similar types of units.

Speech evaluation after near total laryngectomy and total laryngectomy--a comparative acoustic analysis

The practice of Pearson's (1981) technique of near total laryngectomy with speech shunt is evaluated acoustically in 11 subjects using matched esophageal speakers. Not only do these patients vocalize earlier with effortless cease, analysis of their speech both subjectively & by acoustic analysis of the parameters seems definitely to be of superior quality. The functional utility of this technique is addressed in this study justifying its more frequent practice in unilateral lesions of larynx and hypopharynx which defy satisfactory control by conventional conservation laryngeal surgery or radiation therapy. The Oncological outcome will be taken up as a part of a future report when follow up of adequate duration occurs in sufficient number of cases.

Carcinoma of the urinary bladder metastatic to the oral cavity

Oral Metastasis from a carcinoma of the urinary Bladder is extremely uncommon. Two cases of transitional cell carcinoma of the Bladder, presenting eighteen and ten months after initial diagnosis, one with soft tissue metastasis in the upper alveolus and the other with bony metastasis to the mandible are discussed.

Diet and oral premalignancy in female south Indian tobacco and betel chewers: a case-control study

The diets of 158 tobacco/betel quid-chewing women diagnosed with oral premalignant lesions and 155 quid-chewing but lesion-free controls, frequency matched for age, tobacco/betel habits, and socioeconomic status, were assessed using a food frequency survey. Index scores generated from the food frequency survey indicated that the mean levels of consumption for foods of animal origin (p < 0.001), total vegetables and fruit (p = 0.001), vegetables alone (p = 0.006), fruits alone (p = 0.006), and green leafy vegetables (p = 0.015) were significantly lower in cases than in controls. The mean index score for cobalamin (vitamin B12) was lower in cases with a borderline significance (p = 0.05), whereas the indexes for folate and carotene were not significantly different. The analysis of index scores estimating the number of 100-g servings per week of foods of animal origin [meat, eggs, milk, curd (yogurt), fish] consumed revealed that women who ate fewer servings were more likely to have premalignant lesions than those who ate more animal foods [odds ratio (OR) 3.38, 95% confidence interval (CI) 2.07-5.54, p = 0.001]. The risk for low consumption of vegetables was not as significant as that for foods of animal origin. However, those eating low levels of vegetables and low levels of foods of animal origin were at the greatest risk for lesions (OR 5.38, 95% CI 1.72-22.17, p < 0.05). In South Indian female tobacco/betel chewers, a diet deficient in foods of animal origin appears to be a more significant risk factor for oral premalignancy than is a diet deficient in fruits and vegetables.

Interjugular neck dissection and post-operative irradiation for neck control in advanced glottic cancers--are we justified?

At the Kidwai Memorial Institute of Oncology, advanced laryngeal cancers are subjected routinely to primary surgery and/or post-operative radiotherapy (RT). The surgery consists of wide field laryngectomy which entails total laryngectomy, ipsilateral/bilateral thyroid lobectomy, bilateral paratracheal clearance, and bilateral clearance of levels 2, 3 and 4 lymphatics. Post-operative RT is indicated in event of the following histopathological (HPE) situations to consolidate local-regional control: (1) T4 primary; (2) significant subglottic extension; and (3) jugular/paratracheal metastatic deposits. This prospective study highlights the therapeutic efficacy of this protocol at our centre in 45 consecutive T4/T3 glottic cancers and specifically evaluates the role of interjugular dissection and/or post-operative RT in prevention of regional recurrence. Fifty-two per cent of primary lesions needed a post-surgical upstaging as against 14 per cent of the neck lesions. Accordingly 91 per cent of the cases (41/45) qualified for post-operative RT and 82 per cent (37/41) complied with the prescribed schedule. Recurrent disease in the lateral neck was noted in 2/37 who received the prescribed schedule and 1/4 non-compliant cases; while a recurrent central neck disease was noted in 1/37 and 1/4 of these cases respectively. All cases were followed-up for a period of two years and 66 per cent of the evaluable cases for a period of five years. This study confirms conclusively that our treatment schedule yields extremely gratifying two-year local-regional control rates of 89 per cent which translates into a two and five-year actuarial survival rate of 92 and 70 per cent respectively.

Dosimetric accuracy of a dual photon energy linac at low monitor setting for various pulse repetition frequencies

Accuracy of dose delivery at low monitor unit setting is studied for a dual photon energy linear accelerator. Dose delivered per MU is found to be constant for both the photon beams for MU settings above 30. For lower MUs there is definite deviation from the calibrated value and the error is found to be increasing as fewer MUs are set for dose delivery. This dose/MU ratio at low MU setting is found to be dose-rate dependent, showing an increasing trend with pulse repetition frequency (PRF). Also, the dosimetric ratio is observed to be mode dependent; its value for an 18 MV beam is almost double that observed in the case of a 6 MV beam at very low MU setting. The magnitude of this error should be determined for each energy so that appropriate corrections can be applied if very low MUs are to be used.

Intraluminal brachytherapy in carcinoma of the oesophagus: comparison of afterloading techniques

For improved local control or palliation of oesophageal cancers, Intra-luminal brachytherapy (ILB) has emerged as an increasingly popular treatment modality of therapy in recent years. In combination with external radiotherapy, afterloaded ILB can increase local control rates and may prolong survival of these patients. In this paper two techniques of ILB viz., manual and low dose-rate remote after loading methods, using Caesium-137 tubes and pellets respectively, are described in detail. On comparison of these two techniques it was found that both of them were similar with respect to their physical characteristics (dose rate, dose fall-off, maximum spinal cord dose, total reference air kerma, etc.). Clinically, the manual afterloaded ILB technique was found to be easier to use when compared with the low-dose rate remote afterloader. In addition, the number of patients with uterine cancers being high in a developing country, it was found that it was inappropriate to use the low dose remote afterloaders, designed for use in gynaecological cancers, for ILB of oesophageal cancers. Therefore, in the absence of high dose rate afterloaders, which can be utilized for intracavitary treatments of both uterine and oesophageal malignancies effectively, the manual after-loading ILB system as described in this paper could be a practical alternative. Cancer Oesophagus, Intraluminal radiotherapy technique.

Influence of intraluminal brachytherapy dose on complications in the treatment of esophageal cancer

PURPOSE

Demonstration of the influence of intraluminal brachytherapy dose on complications in the treatment of esophageal carcinoma.

METHODS AND MATERIALS

Between January 1990 and June 1991, 75 patients with esophageal cancer were treated with external radiotherapy followed by intraluminal brachytherapy. Patients had a Karnofsky score of over 70, with no supra-clavicular nodal or distant disease. An external radiotherapy dose between 40 and 55 Gy (mean 52 Gy), 5 times a week, 2 to 2.06 Gy/fraction, followed by a single session of Intraluminal brachytherapy using a locally developed, manual, afterloading applicator with Cs-137 sources with dose ranges of 8-10 Gy (Group 1: 42 patients), 10-12 Gy (Group 2: 11 patients), and 12-15 Gy (Group 3: 22 patients) at a mean dose rate of 2.09 Gy/hr was delivered.

RESULTS

The actuarial figures at 1 year were 39% for overall survival, 29% for disease-free survival, and 38% for local control. Fourteen patients (18.6%) developed complications of either an esophageal stricture or fistula. These were dependent on intra-luminal brachytherapy dose, whereas external radiotherapy and intra-luminal brachytherapy doses did not contribute significantly to local control. For Groups 1, 2, and 3, actuarial local control were 28%, 45%, and 63% (p < 0.1) and of complications were 6%, 20%, and 70% (p < 0.001), respectively. Also, on applying the Time/Dose/Fractionation formula on brachytherapy doses, it was found that the complication rate was 6% for TDF of < 31, 25% for TDF of 32-37, and 70% for TDF of > 38 (p < 0.001).

CONCLUSION

External radiotherapy doses in the range of 50 to 55 Gy followed by a dose of 10-12 Gy of intraluminal brachytherapy was found optimal with respect to complications and local control in the radiotherapeutic management of esophageal cancer.

Salivary duct carcinoma

Salivary duct carcinoma is an uncommon malignant tumor that occurs mainly in the parotid gland of elderly men. The 11 cases of salivary duct carcinoma which are included in this study occurred in older men (mean age 56 years) and were located in the parotid (7), submandibular salivary gland (2), and the minor salivary glands in the maxilla (2). The maximum tumor dimension ranged from 3 to 9 cm. Microscopically, all had infiltrating margins, with circumscribed groups of epithelial cells arranged in various patterns; the invasive component was embedded in a desmoplastic stroma. Perineural invasion and lymph node metastasis were noted in seven and three cases, respectively, at the time of initial surgery. Radical surgery was offered to ten patients and postoperative radiotherapy to nine patients. Salivary duct carcinoma appears to be an aggressive tumor with distinctive histological features, which has not been described in the minor salivary glands of the maxilla to date. The clinicopathologic features of these tumors are presented, with a review of the literature.

Neck metastasis from an occult primary--the Kidwai experience

This study highlights our treatment policy in 26 cases of epidermoid metastatic carcinoma in the neck from a primary deemed occult after exhaustive examination of the Upper Aero-digestive Tract (UADT). Planned Radical Neck Dissection (RND) and post-operative radiotherapy (RT) has been the favoured approach in all neck nodes deemed resectable and a loco-regional control rate of 64% was obtaining using this combined modality approach. Pre-operative RT was utilised in three cases with nodal disease of borderline resectability and loco-regional control was achieved in one case. Three cases of massive neck metastasis initially deemed unrectable became amenable to surgical salvage after Radical RT with concurrently administered chemotherapy. Only one of these remained disease free. Overall loco-regional control rate of 55 per cent could be achieved in 20 evaluable patients followed up for two years--three years (mean 30.5 months). Regional failures were noted in 25 per cent of patients while distant spread occurred in 15 per cent, thus accounting for an overall failure rate of 40 per cent. Manifest primaries were documented in 20 per cent, half of which could be salvaged and successfully controlled.

The dose time relationship in the radiotherapy of carcinoma of the cervix--application of CRE formalism

A retrospective analysis of 291 patients with cancer of the uterine cervix treated with a combination of external and intracavitary radiotherapy was carried out. Patients were either treated with 45 Gy in 20 fractions by five fractions per week or with 42 Gy in 14 fractions by three fractions per week or with 42 Gy in 14 fractions by three fraction per week schedule by external radiotherapy. For brachytherapy the total dose was 24 to 32 Gy at a dose rate of 1.4 to 2.2 Gy per hour. Complication were correlated with total CRE values for point A (CRE TA) and for rectum CRE TR. Correlations of CRE TA with overall complication rate (p value < 0.05) and rectal complication rate (p value < 0.01) were excellent. Lack of correlation was observed between CRETR and overall complication rate (p value > 0.1) as well as rectal complication rate (p value > 0.1). In order to limit Grade II and III rectal and bladder complications to acceptable level, in combined external and intracavitary treatments, CRETA value of less than 2500 reu is suggested.

Intraluminal brachytherapy in oesophageal cancer: a simple afterloading technique

Carcinoma of the oesophagus occurs in a good number of patients in any oncology department. Management is either by surgery or radiotherapy. In view of the proximity of the oesophagus to the critical organs in the thorax, effective external beam radiotherapy becomes difficult. A possible solution could be the use of intraluminal brachytherapy (ILB) in addition to external radiotherapy. In this paper a simple and locally developed method of ILB is described which delivers an effective boost to the oesophageal lesion in radical treatments and gives good palliation in advanced cases. Also, this system takes the load off the low dose rate afterloading machines used for intracavitary therapy in gynaecological cancers which otherwise would have also been used for the ILB treatment of oesophageal cancers. A description of the manual afterloading ILB applicator, the technique of its application, and a review of literature, is presented.

Application of radiation effect models in combined external and intracavitary radiotherapy of carcinoma of the uterine cervix

A retrospective analysis of 291 patients with cancer of the uterine cervix treated with a combination of external and intracavitary radiotherapy was carried out. Patients were treated with an external radiotherapy dose of 45 Gy in 20 fractions, 5 fractions per week, or 42 Gy in 14 fractions, 3 fractions per week. For brachytherapy the total dose was 24 to 32 Gy at a dose rate of 1.4 to 2.2 Gy per hour. Treatment results in terms of survival, local disease-free survival and complication rates were compared with cumulative radiation effect (CRE) and extrapolated response dose (ERD) values for point A (CRETA and ERDTA respectively) and for rectum (CRETr and ERDTr respectively). CRETA and ERDTA values did not significantly correlate with local disease-free and survival rates. Correlations of CRETA and ERDTA with overall complication rate and with rectal complication rate (p-value less than 0.025) were good. No significant correlation was observed between CRETr or ERDTr and overall complication rate and rectal complication rate. In order to limit grades II and III rectal complications to acceptable level, in combined external and intracavitary treatment, CRETA and ERDTA values of less than 2,500 and 93 respectively are suggested.

Post laryngectomy rehabilitation the case for planned early speech therapy

This study reflects the efficacy of planned early speech therapy on post laryngectomy rehabilitation. Not only do a larger number of laryngectomees acquire intelligible esophageal speech where therapy is instituted early but also the pace of development and quality of the speech is far superior when compared to those laryngectomees in whom speech therapy was delayed. This paper unequivocally supports the institution of planned early speech therapy in the successful rehabilitation of the laryngectomee. Such therapy can proceed simultaneously with the post operative radiation therapy sans deleterious effects and without prolonging hospital stay with its attendant overheads.

The time dose fractionation (TDF) relationship in the radiotherapy of carcinoma of the cervix

A retrospective analysis of 291 patients with cancer of the uterine cervix treated with a combination of external and intracavitary radiotherapy was carried out. Patients were either treated with 45 Gy in 20 fractions by five fractions per week or with 42 Gy in 14 fractions by three fractions per week schedule by external radiotherapy. For brachytherapy the total dose was 24 to 32 Gy at a dose rate of 1.4 to 2.2 Gy per hour. Treatment results in terms of response, survival, recurrence and complication were correlated with total TDF values for point A (TDFTA) and for rectum TDFTR. Correlations of TDFTA with overall complication rate (p value less than 0.05) and rectal complications rate (p value less than 0.01) were excellent. TDFTA values did not correlate with response, recurrence and survival rates (p value greater than 0.1). Lack of correlation was observed between TDFTR and overall complication rate (p value greater than 0.1) as well as rectal complication rate (p value greater than 0.1). In order to limit grade II and III rectal and bladder complications to acceptable level, in combined external and intracavitary treatments, TDFTA value of less than 150 is suggested.