Biomedical subjects

K Engin

Publications and source records attributed to K Engin.

At least 19 recordsLinked to original sources

PubMed2004

[Calcification of hydrophilic acrylic intraocular lenses: clinical and pathological aspects].

PURPOSE: The aim of this study was to evaluate the clinical aspects of ten eyes with calcified hydrophilic acrylic intraocular lenses and pathological data obtained from seven explanted lenses. MATERIAL AND METHODS: Forty-seven eyes of 40 patients received the same implant in the first 6-month period of 2001. Ten eyes showed intraocular lens opacification detected 6-18 months after the operation: seven lenses were explanted and three were left in place because they were not causing a decrease in visual acuity or glare at light. Five of ten eyes were diabetic. The explanted lenses were examined under the light microscope and the electron microscope. The elemental analysis of the lens surfaces was made by energy dispersive spectrometry. RESULTS: The light microscopy showed an irregular surface covered by a gray-white opacity. The electron microscopy detected multiple granulations on the front and back surfaces of the lenses including some portions of the haptics. The size and density of these granulations were smaller on the back surface. The energy dispersive spectrometry showed the presence of calcium and phosphate on both surfaces. The spikes of calcium and phosphate were smaller for the back surface of the lenses. DISCUSSION: Calcification was predominantly seen on the surfaces that were in contact with aqueous not covered with anterior capsule. Half (5/10) of the cases were diabetic even though 18% of all patients receiving this lens were diabetic. The presence of diabetes is very common in other series. These data suggest the role of a metabolic factor influencing the milieu of the lens in this calcification process. CONCLUSION: Calcification of the hydrophilic acrylic lenses is a relatively serious complication, but the conditions leading to its appearance and the physiopathology have not yet been fully elucidated. The surgeon should be very careful in the choice of the intraocular lens to implant, and even more so if the patient is diabetic.

Aged↗

PubMed2002

Factors influencing cosmetic results after breast conserving management (Turkish experience).

We aimed to determine predictive factors affecting cosmetic results after breast conserving management in breast cancer. Data on 96 patients with 97 breast cancer cases, who had been admitted to Uludağ University M.A. Radiotherapy Center between October 1995 and December 1998 and managed with breast-conserving treatment, were analysed to determine the factors affecting cosmetic outcome. Possible factors affecting cosmesis were grouped as patient-related, tumor-related and treatment-related. Mann-Whitney U test was used in univariate analyses whereas logistic regression was used in multivariate analyses. Median follow-up time was 29.5 months ranging between 11 and 53 months and median age at admission was 50 (range 22-84). Cosmetic results were grouped in five categories; excellent; good; fair; poor and, very poor, using criteria, such as presence of fibrosis, telangiectasia, shape of breast, asymmetry, status of areola, pigmentation. Treated breasts were scored by the patients, three radiation oncologists and a breast surgeon independently. In the analysis performed using scores given by the patients, cases with scores 3 and above (unsatisfactory) were compared with cases with scores below 3 (satisfactory). Eighty-two patients (84%) considered cosmetic result as satisfactory (excellent/good) whereas 15 patients (16%) considered unsatisfactory (fair/poor/very poor). In univariate analysis using Mann-Whitney U test, type of surgery (P=0.0655) was the statistically significant factors affecting cosmetic results. In multivariate analysis using logistic regression, tumor quadrant (P=0.0060) and elapsed radiation therapy days (P=0.0090) were the most significant factors. Median values were taken into consideration for the scores given by the physicians and cases with scores 3 and above (unsatisfactory) were compared with cases with scores below 3 (satisfactory). Eighty-two cases were evaluated as satisfactory (84%) whereas 15 cases were unsatisfactory (16%). In this set of data, patient age (P=0.0144), menopausal status (P=0.0111), institution which surgery was performed (P=0.0045), type of surgery (P=0.0044), placement of metallic clips (P=0.0083) and skin fibrosis (P=0.038) were found to be significant in univariate analysis using Mann-Whitney U test. In multivariate analysis using logistic regression, institution where surgery took place (P=0.0015), menopausal status (P=0.0087) and telangiectasia (P=0.0657) were the most significant factors.

Journal Article↗

PubMed2001

Effects of Taxol plus radiation on the apoptotic and mitotic indices of mouse intestinal crypt cells.

PURPOSE: In this study we investigated the effect of Taxol, radiation, or Taxol plus radiation on highly proliferative normal tissue--the intestinal crypt cells of Swiss albino mice. MATERIALS AND METHODS: Swiss-albino mice, 3-4 months old, were used in this study. Taxol was administered by bolus intravenously through the tail vein. Radiation was given using a linear accelerator. There were four treatment categories, which comprised a total of 34 groups. Each group consisted of five animals. The first category was a control category which comprised one group (n = 5). The second treatment category was Taxol alone which comprised three groups (n = 15). The third treatment category was radiation alone which comprised three groups (n = 15). The fourth treatment category was Taxol plus radiation which comprised 27 groups (n = 135). Mice were killed 24 h after Taxol or radiation or combined administration using ether anesthesia. Using a light microscope, apoptotic and mitotic indices were counted on jejunal crypt cells of mice that were stained with hematoxylin-eosin. Differences between groups were statistically evaluated with Student's t-test. RESULTS: Taxol caused a dose-dependent increase in apoptosis (P = 0.045) and decreased the mitotic index (P = 0.006) at high doses. Similarly, radiation caused a dose-dependent increase in apoptosis (P = 0.046) and decreased the mitotic index (P = 0.299) at higher radiation doses. Compared to radiation alone, Taxol caused a significant induction of apoptosis (P = 0.010). In combination, no significant radiosensitizing effect of Taxol was observed (enhancement ratio < 1), when compared to radiation alone. However, an increase in apoptosis was observed after 24 h of Taxol exposure when compared to 12 or 48 h of Taxol exposure (P = 0.0001 and P = 0.0001). CONCLUSION: These findings suggest that Taxol did not cause a radiosensitizing effect in intestinal crypt cells. However, a 24-hour pretreatment of Taxol exposure followed by radiation caused significant induction of apoptosis and reduction of the mitotic index when compared to other Taxol timing sequences. Thus, the lack of a radiosensitizing effect of Taxol in these proliferative cells may be due to enhanced mitotic death rather than apoptotic death.

Animals↗

PubMed2000

The relationship between genetic susceptibility to head and neck cancer with the expression of common fragile sites.

BACKGROUND: Numerous studies have recently been conducted to investigate genetic mechanisms in cancer causes and pathogenesis. Some of these studies have shown that there were certain specific chromosomal defects in normal cells of cancer patients and in their first-degree relatives. It was suggested that these individuals were susceptible to cancer development when compared with people without these defects. Materials and Methods Chromosomal anomalies, such as gaps, breaks, and acentric fragments, and fragile site expression rates were determined in peripheral blood lymphocyte cultures in 14 head and neck cancer patients, 17 first-degree relatives of these patients, and 20 healthy individuals as a control group in this study. RPMI 1640 medium, composed of aphidicolin, 5-bromodeoxyuridine, and caffeine were used for the induction of fragile sites. RESULTS: In cytogenetic and statistical evaluation, it was observed that both chromosomal aberration rates and fragile site expression frequencies in head and neck cancer patients and in their first-degree relatives were significantly greater than the control group (p <.05). It was found that fragile site expression was site specific in head and neck cancer patients and in their first-degree relatives. These specific sites were determined to be 1p21-22, 1q21, 1q25, 2q21, 2q31-33, 3p14, 16q22-23, 18q21, and 22q12 sites. CONCLUSIONS: These findings support studies showing that the fragile sites might be unstable factors in human genomes and their expression could be affected by some genetic factors, such as tumor suppressor genes and mismatch repair genes, and by some environmental factors, such as benzo (a) pyrene, dimethylnitrosamine, and dimethylsulfate. In conclusion, fragile sites may be playing an important role in the genetic tendency to head and neck cancer. Overexpression of these sites in normal lymphocytes may be used as a reliable marker to determine the genetic susceptibility in head and neck cancer patients and in their first-degree relatives.

Adult↗

PubMed1996

Biological rationale and clinical experience with hyperthermia.

Hyperthermia (HT) as an adjunct to radiation therapy (RT) has been a focus of interest in cancer management in recent years there have been numerous randomized and nonrandomized studies conducted to assess the efficacy of HT combined with either RT or chemotherapy especially in the treatment of superficially seated malignant tumors. The major impact of HT is currently on locoregional control of tumor. Heat may be directly cytotoxic to tumor cells or inhibit repair of both sublethal and potentially lethal damage after radiation. These effects are augmented by the physiological conditions in tumor that lead to states of acidosis and hypoxia. Blood flow is often impaired in tumor relative to normal tissues, and HT may lead to a further decrease in blood flow and augment heat sensitivity. Three major areas of clinical investigation have borne the greatest fruit for HT as adjunctive therapy to RT. These include recurrent and primary breast lesions, melanoma, and head and neck neoplasms. Thermal enhancement ratio was increased in all cases and is approximately 1.4 for neck nodes, 1.5 for breast, and 2 for malignant melanoma. In general, the most important prognostic factors for complete response (CR) are RT dose, tumor size and minimal thermal parameters minimal thermal dose (t43min), mean minimal temperature (Tmin) or T90, i.e., temperature exceeded by 90% of thermal sensors]. The number of HT fractions administered per week appears to have no bearing on the overall response, which may be indicative of the effects of thermotolerance. The total number of HT fractions delivered also appears irrelevant provided adequate HT is delivered in one or two sessions. The major prognostic factors for the duration of local control were tumor histology, concurrent RT dose, tumor depth and Tmin. Although numerous single institution studies showed increased CR rates and improved local control, the efficacy of HT as an adjunct to RT should be assessed with well-designed multi-institutional randomized clinical trials. Such clinical trials are underway.

Chemotherapy, Adjuvant↗

PubMed1995

Thermoradiotherapy in the management of superficial malignant tumors.

In recent years there have been numerous randomized and nonrandomized studies conducted to assess the efficacy of hyperthermia combined with either radiation therapy or chemotherapy, especially in the treatment of superficially seated malignant tumors. The major impact of hyperthermia is currently on locoregional control of tumor. Heat may be directly cytotoxic to tumor cells or inhibit repair of both sublethal and potentially lethal damage after radiation. These effects are augmented by the physiological conditions in tumors which lead to states of acidosis and hypoxia. Blood flow is often impaired in tumor relative to normal tissue, and hyperthermia may lead to a further decrease in blood flow and augment heat sensitivity. Three major areas of clinical investigation have borne the greatest fruit for hyperthermia as adjunctive therapy to radiation therapy. These include recurrent and primary breast lesions, melanoma, and head and neck neoplasms. The thermal enhancement ratio was increased in all cases and is estimated to be 1.4 for neck nodes, 1.5 for breast, and 2 for malignant melanoma. In general, the most important prognostic factors for complete response are radiation dose, tumor size, and minimal thermal parameters (minimum thermal dose, mean minimum temperature or temperature exceeded by 90% of thermal sensors). The number of heat fractions administered per week appears to have no bearing on the overall response, which may be indicative of the effects of thermotolerance. The total number of heat fractions delivered also appears to be irrelevant provided adequate heat is delivered in one or two sessions. The major prognostic factors for the duration of local control are tumor histology, concurrent radiation therapy dose, tumor depth, and mean minimum temperature.

Animals↗

PubMed1994

Tumor extracellular pH as a prognostic factor in thermoradiotherapy.

PURPOSE: Tumor extracellular pH measurements in 26 human tumors were evaluated for the purpose of prognostic indication of response to thermoradiotherapy. METHODS AND MATERIALS: Twenty-six patients (10 male, 16 female; mean age 62 years, range 18-89) were treated with external microwave hyperthermia (915 MHz) combined with radiation therapy. Tumor histologies included: 46% adenocarcinoma, 38% squamous cell carcinoma, 12% soft tissue sarcoma, and 4% malignant melanoma. The mean tumor depth was 1.6 +/- 0.2 cm (range 0.4-3 cm) and the mean tumor volume was 73 +/- 11 cm3 (range 1-192 cm3). The mean radiation dose administered concurrently with hyperthermia was 39 +/- 1 Gy (range 24-60 Gy, median of 40 Gy), in 15 fractions (range 8-25), over 32 elapsed days (range 15-43). The mean number of hyperthermia sessions administered was 5.4 +/- 0.5 (range 2-10). A battery operated pH meter and combination 21 ga recessed glass, beveled needle microelectrodes were used for tumor pH measurements. Calibration in pH buffers was performed before and after each pH measurement. The needle microelectrodes were 2.5 cm in length. RESULTS: A complete response (CR) was obtained in 20 of 26 patients (77%) and a partial response in six (23%). The mean extracellular tumor pH was 6.88 +/- 0.09 in CR patients while it was 7.24 +/- 0.09 in noncompletely responding (NCR) patients (p = 0.08). Logistic regression analysis indicated that the probability of obtaining a complete response was influenced by the tumor volume (p = 0.02), tumor depth (p = 0.05), and extracellular tumor pH (p = 0.08). Lesions in the pH range of 6.00-6.40 and lesions in the pH range of 6.41-6.80 exhibited a CR rate of 100%, while those lesions in the pH range of 6.81-7.20 exhibited a CR of 90% and those in the pH range of 7.21-7.52 exhibited a CR of 50% (p = 0.002). In lesions with depth < or = 1.5 cm, the CR rate was 100% when the tumor pH was < 7.15 and 75% when the tumor pH was > or = 7.15. In lesions with depth between 1.5 and 3 cm, the CR rate was 66% when the tumor pH was < 7.15 and 43% when the tumor pH was > or = 7.15 (p = 0.02). In small tumors, that is, < or = 20 cm3, tumor pH increased with volume, whereas in larger tumors, that is, > 20 cm3, tumor pH decreased as a function of tumor volume. CONCLUSION: Tumor extracellular pH may be useful as a prognostic indicator of tumor response to thermoradiotherapy.

Combined Modality Therapy↗

PubMed1994

Human tumor extracellular pH as a function of blood glucose concentration.

PURPOSE: Mammalian cells are sensitized to hyperthermia when the extracellular pH (pHe) is acutely reduced to < pH 7.0-7.2. However, cells chronically adapted to low pHe may not demonstrate such sensitivity. Although much of the extracellular environment of human tumors is at lower than normal physiological pH, it may be necessary to acutely acidify tumors to cause a change in the therapeutic response to hyperthermia. The purpose of this study was to reduce extracellular pH in human tumors by elevation of blood glucose. METHODS AND MATERIALS: The change in tumor pHe was measured as a function of the change in blood glucose concentration after oral administration of 100 g glucose in 25 fasting, nondiabetic patients. pHe was determined by needle microelectrodes, and blood glucose determined by "Chemstrips" and a glucometer. In some patients blood glucose concentration rose with time after ingestion to a peak change of 50-100 mg/dL between 30-70 min and then began to decrease. In another group of patients glucose concentration increased by 100-200 mg/dL over 30-90 min and remained elevated as if the patients in this group were Type II diabetics. RESULTS: In 14 transient hyperglycemic patients (56%), as blood glucose increased tumor pHe decreased by a mean of -0.17 +/- 0.04 pH units (p < or = 0.0001, range of -0.41-(+)0.07). By contrast in eight persistent hyperglycemic patients, tumor pHe remained unchanged or actually increased an average of 0.03 +/- 0.04 pH units (range of -0.15-(-)0.14). Normal tissue pHe in five patients was unchanged by hyperglycemia, pHe = 7.33 +/- 0.03. Among all patients, 52% exhibited a pHe decrease > or = 0.1 pH unit, and 24% exhibited a pHe decrease > or = 0.2 pH unit. In five transient hyperglycemic patients whose preglucose tumor pHe was between 6.90 and 7.22, the average decrease in pHe induced by hyperglycemia was 0.25 +/- 0.05 pH unit. A linear relationship was observed between the change of pHe and the maximum change in blood glucose such that the greatest decrease in tumor pHe occurred when the glucose change was minimal. The slope was 0.0017 +/- 0.0005 pH units/mg/dL glucose (p < or = 0.005). The linear relationship included both tumors in transient hyperglycemic patients and in persistent hyperglycemia patients. CONCLUSION: Since patients who exhibited the lowest change in blood glucose exhibited the greatest decrease in tumor pHe, it may be that cells in these patients were better able to transport glucose intracellularly which in tumor cells would permit a more rapid production of lactic acid from aerobic and/or anaerobic glycolysis. These data may be helpful in predicting the response of individual patients to oral hyperglycemia as a clinical thermosensitizer.

Blood Glucose↗

PubMed1994

Hyperthermia in cancer treatment (I).

In recent years there have been numerous randomized and nonrandomized studies conducted to assess the efficacy of hyperthermia combined with either radiation therapy or chemotherapy especially in the treatment of superficially seated malignant tumors. The major impact of hyperthermia is currently on loco-regional control of tumor. Heat may be directly cytotoxic to tumor cells or inhibit repair of both sublethal and potentially lethal damage after radiation. These effects are augmented by the physiological conditions in tumor which lead to states of acidosis and hypoxia. Blood flow is often impaired in tumor relative to normal tissue, and hyperthermia may lead to a further decrease in blood flow and augment heat-sensitivity. Three major areas of clinical investigation have borne the greatest fruit for hyperthermia as adjunctive therapy to radiation therapy. These include recurrent and primary breast lesions, melanoma, and head and neck neoplasms. Thermal enhancement ratio was increased in all cases and is estimated to be 1.4 for neck nodes, 1.5 for breast and 2 for malignant melanoma. In general, the most important prognostic factors for complete response are radiation dose, tumor size and minimal thermal parameters (minimal thermal dose (t43min), mean minimal temperature (Tmin) or T90, i.e., temperature exceeded by 90% of thermal sensors). The number of heat fractions administered per week appears to have no bearing on the overall response, which may be indicative of the effects of thermotolerance. The total number of heat fractions delivered also appears irrelevant provided adequate heat is delivered in one or two sessions. The major prognostic factors for the duration of local control are tumor histology, concurrent radiation therapy, dose, tumor depth and Tmin.

Clinical Trials as Topic↗

PubMed1994

Biological rationale for hyperthermia in cancer treatment (II).

Hyperthermia (HT) has gained a great interest in the past two decades. The nature of hyperthermia-induced cell lethality is quite different from that of radiation-induced killing. The G1-phase of the cell cycle is the most resistant to HT while S-phase cells are quite sensitive. In addition to heat-induced cytotoxicity, HT sensitizes cells to low LET ionizing radiation. The mechanism of heat cytotoxicity is distinct from that of ionizing radiation. Unlike the response to ionizing radiation, heat cytotoxicity is influenced by thermotolerance, low pH and nutritional deprivation, but is independent of acute hypoxia. Also, blood flow influences the heating characteristics of a tumor relative to normal tissue, and vascular collapse may occur after heating. Thermotolerance is a nonheritable resistance to HT induced by exposure to heat and other cytotoxic agents. Thermotolerance develops within 2-3 h during exposure to temperatures less than 43 degrees C. Cells exposed for a brief period to temperatures higher than 43 degrees C are sensitized to exposure to temperatures below 43 degrees C. This is called "stepdown heating, SDH". SDH results from the inhibition of thermotolerance development by exposure to the high temperature. Cells are sensitized to HT damage by acutely lowering pH, and thermotolerance development is reduced at low pH. Reduced pH also enhances thermoradiosensitization. Since much of a tumor population is at low pH, and these tumor cells are very likely to be hypoxic and radioresistant, this offers one of the strongest reasons for combining HT with radiation therapy in the treatment of human tumors. The neovasculature in tumors does not respond to increased temperatures as do blood vessels in normal tissues, and these differences in blood flow may lead to selective tumor heating. HT dramatically enhances the cytotoxicity of the electron affinic radiosensitizers in hypoxic cells. HT sensitizes the cell to many cytotoxic agents and even converts some drugs that are innocuous to highly toxic. HT chemosensitization may occur by an increased reaction rate, increased permeability, or decreased repair. The most promising chemosensitization by HT would seem to be with alkylating agents and cis-platinum since they are enhanced at all elevated temperatures.

Animals↗

PubMed1994

Prognostic factors in bilateral breast cancer.

Twenty-nine bilateral breast carcinoma patients were analyzed retrospectively. The incidence of bilateral carcinoma of the breast among unilateral breast cancer patients was approximately 2.4%. Median age was 46 years at the time of first cancer diagnosis (range 26-69 years). The majority of the lesions were invasive ductal carcinoma (86%). Of 58 tumors, 10 were staged as Stage I (17%), 30 as Stage II (52%), 8 as Stage III (14%) and 10 as Stage IV (17%). Patients were treated with various combinations of surgery, radiation treatment and chemotherapy. Of 29 patients with bilateral breast cancer, 5 presented with simultaneous bilateral disease (17%), 7 (24%) with synchronous tumors whereas 17 (59%) developed asynchronous tumors. The mean interval between two cancers was 2.6 +/- 0.6 years. Overall survival was 4.8 +/- 0.7 years and overall 5-year actuarial survival was calculated to be 51%. Age, menopausal status and tumor size at the time of initial cancer correlated with the time interval between two cancers. Age, tumor size and nodal status at the time of initial cancer and the time interval between two cancers correlated with the overall survival.

Actuarial Analysis↗

PubMed1993

Thermoradiation therapy for superficial malignant tumors.

BACKGROUND: Between 1980-1990, 126 patients were treated with radiation therapy (RT) and hyperthermia using 915-MHz external microwave applicators. All but 11 patients had failed to respond to previous therapy. METHODS: The mean tumor volume was 73 +/- 13 cm3, and the mean radiation dose delivered was 45 +/- 1 Gy. Hyperthermia was administered biweekly in 83% of the fields in 5.5 +/- 0.2 sessions. Lesions were stratified by depth. The predictive influence of pretreatment or treatment parameters was analyzed for the probability of response by logistic regression and for the duration of local control by proportional hazards. RESULTS: In tumors considered potentially heatable (i.e., < or = 3-cm deep), the complete response (CR) rate was 70%, whereas the CR rate for patients with tumors deeper than 3 cm was 18% (P < 0.0001). Among superficial lesions of less than or equal to 3-cm depth that exhibited a CR, 14 recurred (26%, 8.7 +/- 1.6 months), while 39 lesions were recurrence-free at last follow-up of 17.8 +/- 1.4 months. The 50% tumor-effective dose was 44 Gy. For superficial lesions that received between 30-60 Gy, the CR rate was 55% when the fraction size was less than 3 Gy, whereas it was 77% when the fraction size was 3-4 Gy (P = 0.05). Multivariate logistic regression analysis indicated that the model best correlating with CR included concurrent radiation dose (P = 0.006) and tumor volume (P = 0.02; model P = 0.0001). Multivariate proportional hazard analysis indicated that the model best correlating with duration of local control included tumor histology (P = 0.004; model P = 0.0007). The overall survival rate of patients with lesions of less than or equal to 3-cm depth who were treated with thermoradiation therapy was 16.1 +/- 1.2 months. For patients with lesions more than 3-cm deep, survival was 8.7 +/- 1.1 months (P < 0.001). Forty-two fields were treated without any skin reactions (33%), 59 exhibited erythema (47%), and 25 experienced thermal blistering (20%). CONCLUSIONS: Treatment of superficial malignant tumors can benefit from the adjuvant use of hyperthermia delivered with external 915-MHz applicators provided tumors are less than 3 cm from the surface and the lateral margins are within the 50% specific absorption rate (SAR) on the surface.

Adenocarcinoma↗

PubMed1993

Cancer of the male breast: the Turkish experience.

Twenty-six patients with male breast cancer who were admitted to the Center of Oncology and Nuclear Medicine, Istanbul, Turkey, between 1980 and 1988, were analyzed retrospectively. Median age was 60 years. Most lesions were infiltrating ductal carcinomas (92%). Of 26 lesions, 9 were staged as stage II (35%), 14 as stage III (54%), and 3 as stage IV (11%). All but five patients underwent unilateral mastectomy (81%). Postoperative treatment consisted of radiation therapy combined with chemotherapy in 11 patients (42%), chemotherapy with or without hormonal therapy in 4 (15%), radiation therapy alone in 10 (38%). Radiation therapy was delivered for a mean total radiation dose of 52 +/- 2 Gy (range 30-60 Gy). Chemotherapy consisted of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in most patients (60%). FAC regimen (5-fluorouracil, Adriamycin, and cyclophosphamide) was given to 6 patients (40%). Six patients were known to have died of breast cancer during follow-up (23%). Fourteen patients were NED (no evidence of disease) at last follow-up (54%). Overall actuarial 5-year survival was calculated to be 37%, and median actuarial survival was 46.6 months. Actuarial 5-year disease-free survival was 27%, and median actuarial disease-free survival was 47.1 months. Only one patient had a local recurrence, and eight patients had 13 distant metastases (31%). Age (P = 0.023), tumor stage (P = 0.055) and nodal status (P = 0.013) were the most significant prognostic factors correlated with the overall survival.

Actuarial Analysis↗

PubMed1993

Occupational physical activity, socioeconomic status, and risks of 15 cancer sites in Turkey.

A multiple-site case-control study of 15 cancers (stomach; colon; rectum; larynx; lung; melanoma; skin; female breast; male breast; cervix; ovary; uterus; prostate; testis; and bladder) was conducted to evaluate their association with occupational physical activity and socioeconomic status (SES). A hospital-based study population (3,486 male cases and 379 female cases, and 2,127 male and 244 female controls) was established in an oncological treatment center in Istanbul, Turkey, from 1979-84. Assessment of physical activity and SES was based on job titles held by the study subjects. Two measures of physical activity were developed based on energy expenditure and 'sitting time' during working hours. Observed risks were adjusted for age, smoking, and SES. Elevated risks were observed among workers who held sedentary jobs for cancers of the colon (odds ratio [OR] = 1.6), rectum (OR = 1.3), melanoma (OR = 1.9), male breast (OR = 1.4), prostate (OR = 5.0), and ovary (OR = 2.0). Cancers of the cervix and uterus showed significantly decreasing risks with decreased activity. Risks of cancers of the colon, rectum, larynx, ovary, and melanoma were enhanced after risks for physical activity indices were adjusted for SES, while the associations between physical activity and cancers of the prostate, cervix, and uterus were weakened after SES adjustment. Risks of melanoma rose significantly with both activity indices after SES adjustment.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1993

'Patchwork' fields in thermoradiotherapy for extensive chest wall recurrences of breast carcinoma.

Chest wall lesions of advanced breast carcinoma in 23 patients were treated with thermoradiotherapy with clinical intent between January 1987 and March 1992. Treatment consisted of external 915 MHz microwave hyperthermia with commercially available applicators and radiation therapy to doses between 32-58 Gy. Twenty-three large, diffuse lesions were treated with multiple field patchwork hyperthermia. All lesions were diffuse with or without multiple nodules < or = 3 cm depth. All lesions had failed previous therapy. The mean number of hyperthermia fields per patient was 3.2 +/- 0.4 (range of 2-7). The complete response rate was 91% in this group of extensive, diffuse lesions treated by the patchwork technique. Mean total radiation dose administered concurrently with multiple field patchwork hyperthermia was 42 +/- 1 Gy. The recurrence rate was 5%. The mean survival in patients who had a complete response was 9.0 +/- 1.3 months. The reduced survival among patchwork treated patients was due to the extensive tumor burden existing outside of the treated fields in these patients. The skin reactions were minor, causing minimal discomfort. There was no evidence of increased thermal damage to skin, or of tumor recurrence at junctions of hyperthermia field overlap. It is concluded that extensive, diffuse lesions of chest wall recurrence of advanced carcinoma of the breast can be treated effectively with multiple field patchwork thermotherapy.

Adult↗

PubMed1993

Hyperthermia and radiation in advanced malignant melanoma.

Advanced melanoma (48 lesions in 40 patients) was treated with external microwave hyperthermia combined with radiation therapy between 1980-1988. Thirty-three lesions in 28 patients were evaluable for tumor response (mean age 64 years, 19 male, 9 female). Evaluable lesions received 13 to 66 Gy (mean 37 +/- 2 Gy) over 5 to 16 fractions (mean of 10) in 14 to 56 elapsed days (mean of 25). Tumor volume (pi/6*length*width*depth) was 62 +/- 16 cm3 (1-377 cm3). Hyperthermia was administered in 6.6 +/- 0.4 sessions (range 1-14), there were 3.2 +/- 0.4 thermal sensors per tumor (range 1-11) and 27 fields were treated twice-weekly (82%). Of the 33 evaluable lesions, 12 exhibited a complete response (36%), and 17 had a partial response (52%). Among the 12 complete responders four recurrences (33%) were observed at 8.6 +/- 1.4 months (median of 8.2 months). In superficial tumors with depth < or = 3 cm and with lateral dimensions within 2 cm of the boundaries of the microwave applicator, the complete response rate was 50% (11/22); whereas for patients with deeper tumors with depth > 3 cm, the complete response rate was 9% (1/11), p = 0.02. The minimal tumor thermal dose during the first hyperthermia treatment session correlated with response (t43min1 = 20 +/- 7 vs. 6 +/- 3 minEq43 degrees C for complete responders and noncomplete responders, respectively, p = 0.06); and 7 of 10 lesions that had t43min 1 > or = 8 minEq43 degrees C achieved a complete response whereas only 5 of 22 lesions (23%) that had t43min1 < 8 minEq43 degrees C did so (p = 0.01). However, neither the minimum tumor temperature during the first treatment, the median minimum tumor temperature over all treatment sessions nor the sum of minimum thermal dose over all treatment sessions correlated with tumor response. Twenty-three patients with 28 lesions died during follow-up (82%). The survival for complete responding patients with superficial lesions was 21.3 +/- 1.5 months compared to 4.5 +/- 0.5 months for patients with superficial lesions that did not experience a complete response (p = 0.0001). For patients with noncomplete responding lesions deeper than 3 cm survival was 4.4 +/- 0.6 months. Twenty lesions were treated without any skin reaction (42%, 20/48). Of the rest, 23 had erythema (48%, 23/48), seven had blistering (14%, 7/48) and one had ulceration of the skin.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1992

Occupational physical activity and colon cancer risk in Turkey.

A case-control study of 107 colon cancer cases and 486 controls from an oncological clinic in Istanbul was conducted to examine the association between occupational physical activity and colon cancer in Turkey, where incidence of this disease is low. Only two of the four activity measures showed evidence of an increased colon cancer risk for sedentary jobs (time spent sitting OR = 1.5 and occupational energy expenditure OR = 1.6); neither was statistically significant. Subjects below age 55 showed higher risk associated with sedentary jobs than did the older age group, probably due to their adoption of a more western lifestyle, including dietary habits, less activity, and other factors that may interact to increase the risk of colon cancer.

Adolescent↗

PubMedDate not supplied

Randomized phase 2 study of radiotherapy alone versus radiotherapy with paclitaxel in non-small cell lung cancer.

This randomized phase 2 study aimed to assess and compare the toxicity and response rates in patients with unresectable non-small cell lung cancer treated with radiotherapy (1.8-2 Gray [Gy] daily, five fractions a week, total 63 Gy) or radiotherapy + paclitaxel administered weekly (1.8 Gy daily, five fractions a week, total 59.4 Gy). Twelve patients in the latter arm received 30 mg/m2 paclitaxel (median six cycles) over a 3-h infusion once weekly. After assessing toxicity, the remaining nine patients received 60 mg/m2 paclitaxel weekly (median six cycles). Response was evaluated radiologically 1 month after treatment. Grade 3 toxicity was 20% and 38% in the radiotherapy and chemoradiotherapy groups, respectively. Overall survival rates in complete and objective (complete plus partial) responders and progression-free survival rate of the objective responders were significantly better in the chemoradiotherapy arm. We believe that using paclitaxel in concurrent chemoradiotherapy regimens may be effective in patients with unresectable, locoregionally advanced non-small cell lung cancer.

Adult↗