Search PubMed⌕ Search

Biomedical subjects

D M Shin

Publications and source records attributed to D M Shin.

At least 73 records · Page 4Linked to original sources
PubMed1996

p53 expressions: predicting recurrence and second primary tumors in head and neck squamous cell carcinoma.

BACKGROUND: The survival rate for head and neck squamous cell carcinoma remains poor despite therapeutic advances over the last two decades. For patients with disease confined to the head and neck, there are two major and biologically distinct patterns of treatment failures after definitive therapy: recurrence of primary disease and development of second primary tumors. Understanding the biological basis of patterns of treatment failure after definitive therapy is needed to guide the development of adjuvant treatment and strategies to prevent second primary tumors. PURPOSE: To determine whether expression of the p53 protein has prognostic significance and/or is associated with patterns of treatment failure, we examined protein expression in primary tumor specimens of patients with head and neck squamous cell carcinoma. METHODS: Immunohistochemical analysis with a monoclonal antibody (DO7) specific for p53 protein was used to detect expression of the protein in formalin-fixed, paraffin-embedded tumor samples from 69 head and neck cancer patients treated with definitive local therapy (surgery and/or radiotherapy) between January 1980 and October 1983 at The University of Texas M. D. Anderson Cancer Center. We quantitated p53 protein expression and assessed its association with duration of patient survival, patterns of treatment failure (recurrence of primary tumor and development of second primary tumor), and other clinical parameters. All reported P values resulted from two-sided statistical tests. RESULTS: We found detectable levels of p53 protein expression in the tumor cell nuclei of 41 of 69 patients. Thirty-six (52%) of 69 patients whose tumors exhibited p53 protein expression in greater than or equal to 10% of the cell nuclei were grouped as p53 positive, and 33 (48%) of 69 patients whose tumors exhibited less than 10% nuclear expression were groups as p53 negative. The clinical characteristics of the patients in the p53-positive, and p53-negative groups were well balanced. Overall survival was significantly lower, and the times to tumor recurrence, to second primary tumors, and to any treatment failure were significantly shorter in the p53-positive group that in the p53-negative group (P=.0002, P=.047, P=.003, and P=.0009, respectively), mainly because the p53 positivity was associated with earlier development of tumor recurrence and second primary tumors. The rate of second primary tumor development per person per year was also significantly higher in the p53-positive group that in the p53-negative group. By use of multivariate analysis according to the Cox regression model, p53 expression status was identified as the most significant predictor of overall survival duration (P=.007), time to tumor recurrence (P=.053), time to second primary tumors (P=.035), and time to any treatment failure (P=.004). CONCLUSIONS: The expression of p53 protein in primary head and neck squamous cell carcinoma was significantly predictive of shorter survival because of its association with earlier development of both tumor recurrence and second primary tumors. Thus, p53 expression may be a valuable marker for identifying individuals at high risk of developing a recurrence of primary disease and second primary tumors who may benefit from adjuvant therapy and chemoprevention after definitive local therapy.

Adult↗
PubMed1996

Molecular and cellular biomarkers for field cancerization and multistep process in head and neck tumorigenesis.

One way to explain the development of head and neck cancer is through the theories of field cancerization, i.e., the exposure of an entire field of tissue to repeated carcinogenic insult, and multistep process, i.e., development of multiple cancers in a predisposed filed through a series of recognizable stages. Recent molecular genetic studies of histologically normal and premalignant epithelia of high-risk subjects and studies of malignant tumors in aerodigestive tract epithelia have identified a continuum of accumulated specific genetic alterations that possibly occur during the clonal evolution of tumors, namely, during the multistep process. Second primary or multiple primary tumors arise in the same fields as independent clones, with similar but unique molecular genetic and/or cellular alterations. Consequently, the assessment of these genetic and phenotypic alterations has been integrated into clinical chemoprevention trials in an effort to identify biomarkers that are also risk predictors and intermediate end points. This review covers candidate biomarkers of the processes of field cancerization and multistep tumor development in aerodigestive tract epithelia, including general and specific genetic markers, proliferation markers, and squamous differentiation markers.

Biomarkers, Tumor↗
PubMed1996

Retrovirus-mediated wild-type p53 gene transfer to tumors of patients with lung cancer.

A retroviral vector containing the wild-type p53 gene under control of a beta-actin promoter was produced to mediate transfer of wild-type p53 into human non-small cell lung cancers by direct injection. Nine patients whose conventional treatments failed were entered into the study. No clinically significant vector-related toxic effects were noted up to five months after treatment. In situ hybridization and DNA polymerase chain reaction showed vector-p53 sequences in posttreatment biopsies. Apoptosis (programmed cell death) was more frequent in posttreatment biopsies than in pretreatment biopsies. Tumor regression was noted in three patients, and tumor growth stabilized in three other patients.

Aged↗
PubMed1996

Treatment of patients with small-cell lung cancer refractory to etoposide and cisplatin with the topoisomerase I poison topotecan.

PURPOSE: This study was designed to assess the anti-tumor activity of topotecan (TPT) in patients with small-cell lung cancer (SCLC) refractory to etoposide. PATIENTS AND METHODS: Refractoriness to etoposide was defined as lack of response to etoposide-containing frontline therapy, or progression during or within 3 months of the last dose of etoposide-containing frontline or second-line therapy. Other eligibility criteria were presence of measurable disease, Zubrod scale performance status (PS) < or = 2, < or = two prior chemotherapy regimens, and adequate renal and liver function. TPT was administered at a dose of 1.25 mg/m2/d for 5 days over 30 minutes every 21 days. RESULTS: Thirty-two patients were registered, of whom 28 are fully assessable. All patients had been treated with frontline etoposide and cisplatin. Three patients (11%) achieved a partial remission (PR) (durations, 7, 8, and 19 weeks) and two (7%) achieved a minor response; five patients (17%) had stable disease and 18 (65%) had progressive disease. One of the three patients who achieved a PR had failed to respond to frontline cisplatin and etoposide. The overall median survival duration was 20 weeks. Grade 3 to 4 granulocytopenia and thrombocytopenia occurred after 70% and 31% of courses administered, respectively. No grade 3 to 4 non-hematological toxicities were observed. Grade 1 or 2 nonhematological toxicities (in percentage of patients) consisted of nausea (41%, 8%) and vomiting (25%, 11%), and alopecia (100%). CONCLUSION: TPT at the dose and schedule used has modest antitumor activity in SCLC patients refractory to etoposide and cisplatin, which indicates that clinical resistance to the topoisomerase II poison etoposide does not confer cross-sensitivity to the topoisomerase I poison TPT. TPT is well tolerated, with myelosuppression of short duration being the most common and limiting toxicity.

Adult↗
PubMed1996

Phase II study of topotecan in patients with advanced non-small-cell lung cancer previously untreated with chemotherapy.

PURPOSE: This study was designed to assess the anti-tumor activity of topotecan (TPT) in patients with advanced non-small-cell lung cancer (NSCLC) previously untreated with chemotherapy. PATIENTS AND METHODS: Patients with stage IIIB or IV NSCLC with measurable disease in nonradiated fields were eligible. Other eligibility criteria were Zubrod performance status (PS) < or = 2 and adequate renal and liver function. TPT was administered at a dose of 1.5 mg/m2/d for 5 days over 30 minutes every 21 days. Of 48 registered patients, 40 were fully assessable. Nineteen patients had adenocarcinoma (AD), 14 squamous carcinoma (SCC), and seven poorly differentiated carcinoma. RESULTS: Six patients (15%) achieved a partial remission (PR) (durations: 8, 14, 18, 28, 56, and 61 weeks) and four patients a minor response; 10 patients had stable disease and 20 patients progressive disease. The PR rate was 36% (five of 14 patients) in patients with SCC versus 4% (one of 26 patients) in those with other histologies (P = .014). The overall median survival time was 38 weeks and 30% of patients were alive at 1 year. Grade 3 to 4 granulocytopenia and thrombocytopenia occurred after 76% and 10% of courses administered, respectively. No grade 3 to 4 nonhematologic toxicities were observed. Grade 1 or 2 nonhematologic toxicities consisted of nausea (46% and 5%), vomiting (31% and 7%), and fatigue (53% and 16%). CONCLUSION: TPT at the dose and schedule used has moderate antitumor activity in NSCLC; its activity is mostly limited to patients with SCC. TPT is well tolerated, with myelosuppression of short duration being the most common and limiting toxicity.

Adenocarcinoma↗
PubMed1996

Detection of chromosome instability of tissue fields at risk: in situ hybridization.

Many human tumors are thought to develop along a multistep pathway in tissues that have encountered long periods of carcinogen exposure and thus have accumulated genetic hits in functional targets relevant to tumor evolution. The cumulative degree of genetic change is dependent on both exogenous (e.g., degree of carcinogen exposure) and endogenous factors (e.g., metabolism of procarcinogens, repair or misrepair capacity, proliferation properties of the tissue, capability of damaged cells to survive). Thus one approach to risk estimation is to measure the accumulated amount of genetic damage in a target tissue at risk for tumor development. Since one cannot predict the exact site of the future tumor, the risk assay must detect a generalized ongoing process of genetic instability from small, random biopsies. The technique of chromosome in situ hybridization involves the use of chromosome- or region-specific probes and provides an ability to directly visualize genetic change (e.g., random or clonal chromosome polysomy and monosomy) on thin tissue sections (where tissue architecture is maintained) or exfoliated cells. Analyses of normal and premalignant lesions adjacent to tumors (e.g., head and neck, lung, bladder, cervix, breast) have demonstrated that chromosome instability can be detected in the field of the tumor (i.e., in normal and premalignant cells in a tissue at 100% risk of tumor development) and the degree of chromosome instability increases with the degree of histologic progression toward cancer. Analyses of premalignant lesions (e.g., oral leukoplakia and erythroplakia from individuals at risk for aerodigestive tract cancer) by chromosome in situ hybridization have uncovered varying degrees of chromosome instability. However, approximately half of those individuals who showed a high degree of chromosome instability in biopsies subsequently developed aerodigestive tract cancer. Of interest, half of these tumors have developed away from the biopsied site, suggesting that the detection of a chromosome instability process in one aspect of the tissue might yield risk information for the total tissue field. These studies also suggest that chromosome in situ hybridization might be useful for identifying individuals with high tumor risk who might benefit from chemopreventive intervention.

Bronchi↗
PubMed1996

Genetic instability and the development of recurrence of primary tumor and second primary tumor during head and neck tumorigenesis.

To determine whether the degree of genetic instability is associated with the development of recurrence of primary tumor (RPT) and second primary tumor (SPT), we examined 46 cases of head and neck squamous cell carcinomas (HNSCC) by nonisotopic in situ hybridization using chromosome specific DNA probes for chromosome 9 and 17. Forty-six cases were classified into three groups; group I, 15 cases without developing RPT and SPT; group II, 21 cases with RPT, and group III, 10 cases with SPT. We demonstrated the statistical significant increment of genetic instability in terms of normalized chromosome index (NCI) and polysomy index (PI) of chromosome 9 and 17 from normal adjacent to malignant lesions (ANL), to hyperplasia (HYP), to dysplasia (DYP), to squamous cell carcinomas (SCC). Our results demonstrated the trend of increased chromosome indices as the tissue progressed from ANL to SCC in group II over group I. However, when we compared the genetic instability between group I and the specimens from the patients who developed RPT within 6 months (group III), we found the significant increment of PI of both chromosome 9 (0.84 +/- 0.54 vs 1.25 +/- 0.46, p = 0.10) and 17 (1.02 +/- 0.62 vs 1.89 +/- 0.87, p = 0.06) on ANL in the later group. Our results also demonstrated the higher trend of genetic instability on ANL in group III over group I as shown by the statistical significance of NCI of both chromosome 9 (0.98 +/- 0.12 vs 1.06 +/- 0.02, p = 0.05) and 17 (1.02 +/- 0.09 vs 1.10 +/- 0.05, p = 0.05). These results suggested that the degree of genetic instability might be used as a potential molecular marker for the risk assessment of early RPT and SPT development during head and neck tumorigenesis.

Adult↗
PubMed1996

Genetic instabilities of chromosome 9, 17 and accumulation of p53 overexpression during multistage tumorigesis in head and neck cancer.

Malignant transformation and tumor progression are currently thought to be the result of the accumulation of genetic alterations in critical genes, the proto-oncogenes and the tumor suppressor genes. Among the tumor suppressor genes, the p53 tumor suppressor gene mutations are the most prevalent. In order to determine genetic instability and p53 expression, we analyzed the genetic changes of chromosome 9 and 17 by non-isotopic in situ hybridization in formalin-fixed, paraffin embedded tissues and calculated for normalized chromosome index (NCI) and polysomy index (PI), and the expression of p53 by using immunohistochemistry (IHC). The means of chromosome 9 and 17 NCI were found to increase gradually as the tissues progressed from normal to squamous cell carcinoma; 1.02 and 1.03, respectively, in normal adjacent tissue (ANL), 1.19 and 1.20 in hyperplasia (HYP), 1.28 and 1.31 in mild dysplasia (MD), 1.38 and 1.43 in moderate dysplasia (ModD), 1.39 and 1.66 in severe dysplasia/carcinoma in situ (SD/CIS), and 1.65 and 1.83 in squamous cell carcinoma (SCC). Moreover, the PI 9 and 17 means also increased as the tissues passed from histologically normal epithelium to HYP to dysplasia (DYP) to cancer. In ANL, PI 9 and 17 means were 0.90 and 1.53 percent, compared to 3.78 and 3.38 percent in HYP, 3.73 and 5.12 percent in MD, 5.66 and 8.47 percent in ModD, 13.56 and 20.99 percent in SD/CIS, and 17.74 and 22.50 percent in SCC. Interestingly, p53 expression also increased continuously, not only in amount but also in the incidence of its expression, as the tissues progressed from normal to cancer, 2.29 percent in ANL, 4.65 percent in HYP, 9.09 per cent in MD, 9.58 per cent in ModD, 29 percent in SD/CIS, and 38.67 per cent in SCC in the amount; and 3 of 33 (9%) in ANL, 6 of 37 (16%) in HYP, 5 of 21 (24%) in MD, 3 of 12 (25%) in ModD, 8 of 18 (44%) in SD/CIS, and 24 of 49 (49%) in SCC in the incidence. Our studies demonstrated that genetic instability and p35 expression occurred very early from ANL to SCC and increased gradually through HYP, DYP, to SCC in head and neck cancer. The genetic instability and the loss of normal p53 function play the potential role in multistep tumorigenesis in head and neck cancer and might be the useful biomarkers in assessing the risk of tumor development.

Carcinoma, Squamous Cell↗
PubMed1995

Prospective study of combination chemotherapy with cyclophosphamide, doxorubicin, and cisplatin for unresectable or metastatic malignant pleural mesothelioma.

BACKGROUND: This study was designed to determine the efficacy and side effects of a combination of cyclophosphamide (C), doxorubicin (D), and cisplatin (P) in patients with inoperable, unresectable, or metastatic malignant pleural mesothelioma. METHODS: Twenty-three patients with unresectable or metastatic malignant pleural mesothelioma were entered onto the study. The median age was 62 years (range, 42-74 years); there were 20 males and 3 females; the median performance status was 1 (Zubrod's scale). The histologic types included epithelial (14 patients), sarcomatoid (4 patients), unclassified (4 patients), and mixed type (1 patient). Twenty patients were known to have been exposed to asbestos and 3 were not. All patients were treated with the following starting dose of chemotherapy: a cycle comprised of C, 500 mg/m2 intravenously, day 1; D, 50 mg/m2 intravenously, day 1; and P, 80 mg/m2 intravenously, day 1 every 3 weeks. The cisplatin dose was reduced to 50 mg/m2 for the subsequent courses. For the assessment of tumor response, all patients had computed tomography scans of the chest after each three cycles of chemotherapy. RESULTS: Overall, 7 of 23 patients (30%) had partial responses (durations of responses [weeks]: 158+, 91+, 70+, 41+, 40, 39, 25), three had minor responses, and 14 had stable or progressive disease. One partial responder later underwent surgical resection and no viable tumors cells were found in the pathologic specimen. All patients have stopped treatment, and eight are still alive. The most common side effect was granulocytopenia (grade 4, 52%; grade 3, 17%). Other hematologic side effects were modest. Nonhematologic side effects included mild to moderate nausea and vomiting, neutropenic fever (three patients), peripheral neuropathy (one patient), and congestive heart failure (one patient). The overall median duration of survival was 60 weeks. CONCLUSION: Combination chemotherapy with CDP was well tolerated and had significant activity against unresectable or metastatic malignant pleural mesothelioma. The median duration of responses was 60 weeks; however, the survival rate was far from satisfactory. Continued development of new approaches including the biologic understanding of tumor development and testing new agents is warranted.

Adult↗
PubMed1995

Evaluation of cognitive function in patients with limited small cell lung cancer prior to and shortly following prophylactic cranial irradiation.

PURPOSE: Cognitive deficits after treatment for small cell lung cancer (SCLC) have been attributed to prophylactic cranial irradiation (PCI). A prospective study of neuropsychological function was undertaken to document the evolution and magnitude of neuropsychologic deficits. METHODS AND MATERIALS: Thirty patients with limited stage SCLC who responded well (29 complete response (CR), 1 partial response (PR)) to combination chemotherapy plus thoracic irradiation or resection were studied with neuropsychological tests in the cognitive domains of intelligence, frontal lobe function, language, memory, visual-perception, and motor dexterity prior to a planned course of PCI. Nine patients had a neurologic history that could influence testing. RESULTS: An unexpected 97% (29 out 30) of patients had evidence of cognitive dysfunction prior to PCI. The most frequent impairment was verbal memory, followed by frontal lobe dysfunction, and fine motor incoordination. Of the patients with no prior neurologic or substance abuse history, 20 out of 21 (95%) had impairments on neuropsychological assessment. This neurologically normal group was just as impaired as the group with such a history with respect to delayed verbal memory and frontal lobe executive function. Eleven patients had neuropsychological testing 6 to 20 months after PCI; no significant differences were found from their pretreatment tests. CONCLUSIONS: A high proportion of neurologically normal patients was limited SCLC and favorable responses to combination chemotherapy have specific cognitive deficits before receiving PCI. Short-term (6 to 20 months) observations after PCI have shown no significant deterioration.

Adult↗
PubMed1995

Interdigitating versus concurrent chemotherapy and radiotherapy for limited small cell lung cancer.

PURPOSE: Sequencing and timing of chemotherapy and radiotherapy for limited small-cell lung cancer (LSCLC) was studied in two consecutive trials. METHODS AND MATERIALS: In the interdigitating (IDG) trial, three cycles of COPE (cyclophosphamide 750 mg/M2 i.v. Day 1, vincristine 2 mg i.v. Day 8, cisplatin [DDP] 20 mg/M2 Days 1-3, etoposide 100 mg/M2 i.v. Days 1-3), were followed by thoracic radiation therapy (1.5 Gy bid 5-6 h apart, repeated twice at 3-week intervals) to give 45 Gy in 9 weeks; COPE was given during the intervals and for two more cycles. Operable patients had thoracotomy followed by IDG. Prophylactic cranial irradiation (PCI), 2.0 Gy x 15 fractions with a total dose of 30 Gy in 3 weeks, was given to the complete responders (CR) after completion of chemotherapy. In the concurrent (CON) trial, patients received DDP 60 mg/M2 i.v. Day 1, and etoposide 120 mg/M2 i.v. Days 1-3 for four cycles, every 3 weeks, and concurrent thoracic radiation therapy to 45 Gy with either 1.8 Gy daily, for 5 weeks or 1.5 Gy bid for 3 weeks. Prophylactic cranial irradiation (PCI) was given to the complete responders, 2.5 Gy daily for 2 weeks (25 Gy) (approximately 3 months after the initiation of treatment). RESULTS: The IDG group had 28 evaluable patients with median follow-up of 17.5 months. The CON group had 33 evaluable patients with median follow-up of 21 months. Overall survival rates for IDG patients were 79% at 1 year, 39% at 2 years, 30% at 3 years, and 27% at 4 years compared to 93%, 70%, 51%, and 46%, respectively, for the patients treated with CON (p = 0.01). Loco-regional recurrence (44%) and distant metastasis (48%) was more frequent as the first site of failure in the IDG group compared to the CON group (30% and 30%, respectively). Brain metastases constituted 30% of first metastases with IDG compared to none with CON. Esophagitis was significantly greater with CON. Hematologic and pulmonary toxicity were similar with IDG and CON. One death due to infection was seen in each treatment group. CONCLUSION: Concurrent chemoradiotherapy appears to be more effective than IDG. Earlier administration of PCI with concurrent chemotherapy and thoracic irradiation may reduce the risk of brain metastasis.

Adult↗
PubMed1995

p53 and retinoid chemoprevention of oral carcinogenesis.

We studied p53 protein's pattern of expression, association with retinoid response or resistance, and modulation by retinoid intervention in oral premalignancy. These p53 analyses were included in a prospective trial of the retinoid isotretinoin (1.5 mg/kg/day for 3 months) in 40 patients (45 oral premalignant lesions). Seven nonsmoking subjects (eight oral biopsies) were included as a control. Protein levels of p53 were determined separately for the whole epithelium and the basal, parabasal, and superficial layers. A wide range of accumulated p53 protein levels occurred in 40 (89%) of 45 lesions in basal and parabasal but not superficial layers. No p53 protein was detected in any normal controls. Accumulation of p53 increased in direct association with histological grade (P = 0.0004). An inverse relationship occurred between the levels of accumulated p53 protein and response to isotretinoin (P = 0.006). High-dose isotretinoin did not modulate accumulated p53 protein expression.

Adult↗
PubMed1995

Phase II study of docetaxel for advanced or metastatic platinum-refractory non-small-cell lung cancer.

PURPOSE: We conducted a phase II study to determine the response to and toxicity of docetaxel (Taxotere; Rhône-Poulenc Rorer Pharmaceuticals, Inc, Collegeville, PA) in patients with advanced non-small-cell lung cancer refractory to prior platinum-containing chemotherapy (PCC) regimens. PATIENTS AND METHODS: Forty-four patients with stage IIIb or IV platinum-refractory non-small-cell lung cancer were treated with 100 mg/m2 of docetaxel intravenously over 1 hour every 3 weeks. The responses of 42 of 44 patients were assessable. Most patients had a Zubrod performance status of 1; the predominant histologic type was adenocarcinoma (61%), and 91% of patients had stage IV disease. RESULTS: Nine of 42 assessable patients (21%) achieved a partial response to treatment. The median response duration (from response to progression) was 17 weeks, and the projected median survival duration of all patients is 42 weeks (51 weeks for adenocarcinoma and 22 weeks for nonadenocarcinoma). Grade 3/4 neutropenia occurred in 85% of patients and was associated with fever that required intravenous antibiotics in 16% of patients (3% of cycles). Other acute side effects included easily treated hypersensitivity reactions and dermatitis. Cumulative side effects included fluid retention and neuropathy. CONCLUSION: Docetaxel administered at 100 mg/m2 intravenously every 3 weeks has notable activity against platinum-refractory non-small-cell lung cancer, with a 21% major response rate. Primary side effects were neutropenia, hypersensitivity, and fluid retention.

Adenocarcinoma↗
PubMed1995

Three-dimensional kinematic analysis of baseball pitching in acceleration phase.

To examine the relationships of pitching performance to maximum external rotation of the shoulder and to time in the acceleration phase, 3 male baseball pitchers were tested using three-dimensional cinematography. Analysis indicated that increasing maximum external rotation of the shoulder at the very beginning of the acceleration phase would help to generate a higher pitching ball velocity since a greater linear and angular displacement could be used to accelerate the throwing forearm. Slowing the wrist action just before ball-release may be a key technique to increasing pitching velocity of the ball.

Adult↗
PubMed1994

Differential expression of nuclear retinoid receptors in normal, premalignant, and malignant head and neck tissues.

Retinoids reverse premalignant lesions and inhibit the development of second primary cancers in patients with upper aerodigestive tract cancers. It is thought that these effects result from the ability of retinoids to restore normal cell growth and differentiation. Since nuclear retinoid receptors (RARs and RXRs) are the ultimate mediators of retinoid actions, alterations in their expression could lead to cancer development. To determine whether the expression of the mRNAs of the receptors is related to the development of head and neck squamous cell carcinoma (HNSCC), we used digoxigenin-labeled antisense riboprobes of RAR-alpha, RAR-beta, RAR-gamma, RXR-alpha, and RXR-beta for in situ hybridization to histological sections of specimens from 7 normal volunteers and 31 HNSCC patients. All 31 tissue specimens contained carcinomas, 16 also contained dysplastic lesions, 22 also contained hyperplastic lesions, 17 also contained adjacent normal tissue, and 6 contained all 4 types of tissue. All specimens from normal volunteers expressed the 5 receptors. Similar levels of RAR-gamma and RXR-alpha and RXR-beta mRNAs were detected in most of the adjacent normal, hyperplastic, dysplastic, and malignant tissues. RAR-alpha mRNA was detected in 94% of adjacent normal tissues and hyperplastic tissues, in 87% of dysplasias, and in 77% of HNSCCs. In contrast, RAR-beta mRNA was detected in about 70% of adjacent normal and hyperplastic lesions, and its expression decreased further to 56% of dysplastic lesions and to 35% of HNSCCs. The difference in RAR-beta level in carcinoma and adjacent normal tissues was significant (P < 0.05). These results indicate that the decreased expression of RAR-beta may be associated with HNSCC development.

Carcinoma, Squamous Cell↗
PubMed1994

Dysregulation of epidermal growth factor receptor expression in premalignant lesions during head and neck tumorigenesis.

The development of head and neck cancer, believed to result from field cancerization and a multistep process of tumorigenesis, is often associated with an accumulation of genotypic and phenotypic alterations. The phenotypic changes could be the result of dysregulation of growth control genes such as epidermal growth factor receptor (EGFR). With the goal of identifying a potential biomarker of the multistep process of tumorigensis, we studied specimens of 36 head and neck squamous cell carcinomas from 5 different sites that contained normal epithelia and/or premalignant lesions adjacent to the tumors. Almost all of the individuals from whom these specimens were obtained had been exposed to first-hand smoking and/or alcohol consumption. Using a monoclonal anti-EGFR antibody for immunohistochemical analysis on paraffin-embedded sections with attached 886 cells for internal control, the levels of EGFR expression were assessed by image analysis. The relative staining intensity of EGFR in normal epithelia adjacent to tumors was 2-fold higher than that in normal control epithelium (P = 0.021), suggesting that, even in histologically normal epithelium, EGFR was already up-regulated in tissues surrounding tumors. These findings supported the theory of field cancerization in head and neck tumorigenesis. As tissue progressed from normal tissue adjacent to tumor to hyperplasia and to dysplasia, EGFR expression remained elevated. However, in the step from dysplasia to squamous cell carcinoma, EGFR expression was further and dramatically up-regulated (P = 0.01). Therefore, these results indicate that EGFR dysregulation happens in two steps, the moderate up-regulation of EGFR expression in normal epithelium adjacent to tumor and the further up-regulation of EGFR expression in the change from dysplasia to squamous cell carcinoma. In summary, the studies presented here indicate that EGFR dysregulation might be a useful marker for identifying individuals at risk of tumor development and an intermediate end point in chemoprevention trials.

Adult↗
PubMed1994

Thymoma. A retrospective study of 87 cases.

BACKGROUND: The authors retrospectively analyzed 87 patients with malignant thymoma treated at M.D. Anderson Cancer Center between 1951 and 1990. The analysis examined the clinical stages, histologic types, and treatment modalities and attempted to determine if chemotherapy had an impact on survival. METHODS: The patients were divided into three groups by their year of treatment and treatment modality. Patients treated between 1951 and 1975 were in Group I; patients treated between 1976 and 1980 were in Group II; and patients treated between 1981 and 1990 were in Group III. Most of the patients (18 [72%] in Group I; 16 [62%] in Group II; and 18 [50%] in Group III) had surgical resection alone or with radiotherapy. Patients with advanced-stage disease in Group I received single-agent chemotherapy, whereas patients with advanced-stage disease in Group II received a different, combination chemotherapy regimen, and those in Group III were treated primarily with cisplatin- and doxorubicin-based combination chemotherapy, e.g., the cyclophosphamide doxorubicin, and cisplatin with or without prednisone. The 17 patients treated with cisplatin with or without prednisone were separately evaluated for survival according to their response. RESULTS: Twenty-eight patients (5 [20%] in Group I; 6 [23%] in Group II; and 17 [47%] in Group III) received chemotherapy alone or after surgery or radiotherapy. The cisplatin with or without prednisone regimen was used in 17 Group III patients for initial treatment or for relapse. The overall response rate among the patients receiving the cisplatin with or without prednisone regimen was 64%; 6 (35%) had a complete response, and 5 (29%) had a partial response. Thirty-one (36%) of the 87 total patients had 45 recurrent tumors; the lung (29%), pleura (22%), and mediastinum (18%) were the most common sites of recurrence, whereas bone was the most common distant metastatic site. The 5-year survival rate was 70% in patients with Stage I disease, 71% in patients with Stage II or III disease, and 46% in patients with Stage IV disease. The 10-year survival rate was 70% in patients with Stage I disease, 47% in patients with Stage II or III disease, and 21% in patients with Stage IV disease. Statistical analysis indicated a significant difference among the survival rates of patients with noninvasive Stage I, invasive Stage II plus III (P = 0.033), and Stage II plus III and IV tumors (P = 0.056), but not between patients with Stage II or III tumors. Patients with a major response to the cisplatin with or without prednisone regimen had a significant survival improvement compared to those with no response (P = 0.002, log-rank test). CONCLUSIONS: Because thymoma is a chemosensitive tumor and frequently recurs in patients with Stage II or greater disease, chemotherapy carries a potential survival benefit and should be incorporated into the multimodality approach to prolong disease-free survival.

Adolescent↗