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Biomedical subjects

P A Treseler

Publications and source records attributed to P A Treseler.

At least 19 recordsLinked to original sources
PubMed2003

Accuracy of fine-needle aspiration cytology in patients with radiation-induced thyroid neoplasms.

BACKGROUND: Fine-needle aspiration cytology (FNAC) is useful for selecting patients with thyroid nodules for thyroidectomy. Its value in patients who have been exposed to low-dose therapeutic radiation is questionable because these patients have an increased risk of multifocal benign and malignant tumours, and thyroid cancer is common in such patients. METHODS: Between 1960 and 1999, 171 patients with one or more thyroid nodules who had a history of exposure to radiation underwent operation; 49 of these patients had preoperative FNAC. The cytology results in these 49 patients were compared with those of an age- and sex-matched control group of patients with thyroid nodules who did not have a history of radiation exposure. RESULTS: Of those who had been exposed to radiation, six of 20 patients with 'benign' cytology by FNAC and six of 16 patients with 'suspicious' cytology had thyroid cancer. All 13 specimens considered to be malignant on FNAC were indeed malignant. There was a higher rate of false-negative cytological examinations among patients with a history of irradiation that in those without. CONCLUSION: FNAC of thyroid nodules in patients with a history of irradiation is not as accurate as that in non-irradiated patients, primarily because of coexisting occult thyroid cancers.

Biopsy, Needle↗
PubMed2001

Completely resected anaplastic thyroid carcinoma combined with adjuvant chemotherapy and irradiation is associated with prolonged survival.

BACKGROUND: The prognosis of anaplastic thyroid carcinoma (ATC) has been dismal. The objective of this study was to identify prognostic factors in patients who had prolonged survival. METHODS: Patients with ATC were identified from a computer database at a tertiary referral center. Univariate and multivariate analyses for survival differences were performed using the Kaplan-Meier log-rank statistic and the Cox proportional hazards model, respectively. RESULTS: Of the 33 evaluable patients, median survival was 3.8 months. Median age was 69 years. Prior goiter was present in 6 patients (18%), and 6 (18%) had prior thyroid carcinoma. Median tumor size was 6 cm, and 12 (36%) had adjacent well-differentiated carcinoma. Of the 26 patients who underwent neck exploration, 8 patients were potentially cured and received postoperative chemotherapy and irradiation; 4 (50%) were surgically macroscopically free of disease, and 4 (50%) patients had minimal residual disease after total thyroidectomy and resection of tumor adherent to adjacent structures. Four of these 8 patients survived longer than 2 years; their 5-year survival estimate was 50%. Eighteen patients underwent palliative resection of neck disease, leaving macroscopic residual disease or distant metastases; postoperative adjuvant chemotherapy and irradiation were administered in 16 of these 18 patients. Seven patients were treated with only chemotherapy and irradiation. In patients treated with potentially curative resection, median survival was 43 months compared with 3 months with palliative resection (P =0.002); the median survival of 3.3 months with only chemotherapy and irradiation was no different than palliative resection (P =0.63). No association was found between survival and age, prior goiter, prior thyroid carcinoma, adjacent differentiated carcinoma, or tumor size. CONCLUSIONS: Although the prognosis of most patients with ATC continues to be poor, complete resection of ATC combined with postoperative adjuvant chemotherapy and irradiation resulted in long-term survival, even with persistent minimal disease that remained on vital structures. An aggressive attempt at maximal tumor debulking followed by adjuvant therapy was found to be warranted in patients with localized ATC.

Age Factors↗
PubMed2001

Mouse intestinal goblet cells expressing SV40 T antigen directed by the MUC2 mucin gene promoter undergo apoptosis upon migration to the villi.

Mucinous colorectal cancers exhibit a characteristic set of molecular genetic alterations and may be derived from progenitor cells committed to the goblet cell lineage. Previously, we demonstrated that the MUC2 mucin gene promoter drives transgene reporter expression with high specificity in small intestinal goblet cells of transgenic mice. On the basis of these experiments, we reasoned that the MUC2 promoter could be used to drive SV40 T antigen (Tag) expression in the same cell type, decoupling them from their normal antiproliferative controls. A line of mice was established (MUCTag6) that expressed Tag in intestinal goblet cells as determined by RNA blot and immunohistochemical analysis. These goblet cells were markedly involuted however, most notably in the villi. Endogenous intestinal MUC2 message levels were reduced to about one third the normal level in these mice. However, absorptive cell lineage markers were comparable with nontransgenics. Bromodeoxyuridine-positive S-phase cells are limited to crypts in nontransgenic intestine but are present in both crypts and villi in MUCTag6. In contrast, mitotic cells were not present in the villi, indicating that MUCTag6 villi goblet cells do not progress into M phase. Apoptotic cells positive for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling were increased more than fourfold in MUCTag6 villi (P < 0.0001), and apoptotic goblet cells were evident. Electron microscopic examination of MUCTag6 intestinal villi revealed the presence of degraded cell remnants containing mucin goblets together with other cell debris, further indicating apoptosis of the goblet cell lineage. Thus, the expression of Tag in intestinal goblet cells releases them from normal antiproliferative controls, causing their inappropriate entry into S phase even after they transverse the crypt/villus junction. They do not, however, progress to M phase. Instead, they undergo apoptosis with a high degree of efficiency in S or G(2) phase. These experiments demonstrate that apoptosis effectively blocks inappropriate goblet cell proliferation in the intestine, supporting its proposed role as an antineoplastic mechanism.

Animals↗
PubMed2001

Coexisting chronic lymphocytic thyroiditis and papillary thyroid cancer revisited.

The effect of chronic lymphocytic thyroiditis (CLT) on the behavior of papillary thyroid cancer (PTC) remains unclear. In recent studies the presence of CLT in patients with PTC was reported to be associated with a lower recurrence rate and an improved survival rate. Furthermore, patients with PTC and tumor infiltrating lymphocytes (TILs) have been reported to have lower recurrence rates and a lower frequency of distant metastases. Because of these and other observations, a tumor immune response in PTC has been suggested. The aim of our study was to determine: (1) the relative frequency of CLT in PTC; (2) the prognostic significance of CLT in patients with PTC; and (3) if TIL occurs independently or in association with CLT. A 10-year retrospective study of patients who underwent initial thyroidectomy for PTC from 1986 to 1996 was completed. The extent of thyroid lymphocytic infiltration was determined within the tumor, surrounding the tumor, and in the distant parenchyma by two independent observers blinded to the clinical data. Dense focal/diffuse lymphoid aggregates throughout the thyroid gland were diagnostic of CLT and when present within or surrounding the tumor were designated TILs. A total of 136 patients with PTC (typical and follicular variant of PTC histologic subtypes) were identified with a mean follow-up of 4.4 years and a 8% mortality rate at 10 years. Thirty percent of the patients with PTC had coexisting CLT, and 65% of these patients with CLT had positive anti-thyroglobulin antibodies. Patients with coexisting CLT and PTC were younger (p < 0.05), more likely to be female (p < 0.05), and more likely to have multicentric tumors (p < 0.001) compared to patients without CLT. Only 5% of patients had TILs without CLT, but 82.5% of patients with CLT had TILs identified (p < 0.0001). By univariate analysis CLT, age, gender, stage of PTC, tumor multicentricity, and tumor size were significant prognostic factors. Only age and TNM stage of PTC remained independent prognostic factors by multivariate analysis. We found a similar frequency (30%) of coexisting CLT and PTC as reported by others; but, more importantly, the presence of TILs primarily occurred in association with CLT. The presence of CLT in patients with PTC correlated with an improved prognosis. It was not an independent prognostic factor, however, and was not associated with a lower recurrence rate or a lower frequency of distant metastasis.

Chronic Disease↗
PubMed2001

Micrometastasis to in-transit lymph nodes from extremity and truncal malignant melanoma.

BACKGROUND: The sentinel lymph node (SLN) is the first lymph node in the regional nodal basin to receive metastatic cells. In-transit nodes are found between the primary melanoma site and regional nodal basins. To date, this is one of the first reports on micrometastasis to in-transit nodes. METHODS: Retrospective database and medical records were reviewed from October 21, 1993, to November 19. 1999. At the UCSF Melanoma Center, patients with tumor thickness > 1 mm or < 1 mm with high-risk features are managed with preoperative lymphoscintigraphy, selective SLN dissection, and wide local excision. RESULTS: Thirty (5%) out of 557 extremity and truncal melanoma patients had in-transit SLNs. Three patients had positive in-transit SLNs and negative SLNs in the regional nodal basin. Two patients had positive in-transit and regional SLNs. Three patients had negative in-transit SLNs but positive regional SLNs. The remaining 22 patients were negative for in-transit and regional SLNs. CONCLUSIONS: In-transit SLNs may harbor micrometastasis. About 10% of the time, micrometastasis may involve the in-transit and not the regional SLN. Therefore, both in-transit and regional SLNs should be harvested.

Extremities↗
PubMed2001

Evaluation of sentinel lymph node status in spindle cell melanomas.

BACKGROUND: The propensity for spindle cell melanoma to metastasize to the lymph node is relatively low despite its relative thick depth. To date, there are no published reports on the sentinel lymph node (SLN) status in patients diagnosed with spindle cell melanoma and desmoplastic malignant melanoma (DMM). OBJECTIVE: Our purpose was to report our experience on the SLN status in spindle cell melanoma and DMM. METHODS: We undertook a retrospective database and medical record review from Oct 21, 1993 to Sept 29, 1999. At the University of California at San Francisco Melanoma Center, patients with tumor thickness greater than 1 mm or less than 1 mm with high-risk features are managed with preoperative lymphoscintigraphy, selective SLN dissection, and wide excision. RESULTS: Of 29 patients diagnosed with spindle cell melanoma and DMM, 28 had negative SLNs and are free of disease except for one patient who experienced splenic, bony, and brain metastases. The mean follow-up in this population was 16.5 and 11 months, respectively. CONCLUSION: Our preliminary findings show that SLNs from patients diagnosed with spindle cell melanoma and DMM only rarely harbor micrometastasis despite their relative thickness. A larger number of cases from multicenter databases may further define the true biology of SLNs in this melanoma variant.

Adult↗
PubMed2000

Multidisciplinary approach to selective sentinel lymph node mapping in breast cancer.

Although the role of axillary lymph node dissection is controversial with respect to survival benefits, its role as a staging procedure has been well established since nodal involvement is the most reliable prognostic indicator for patients with breast cancer. Selective sentinel lymph node (SLN) dissection is gaining acceptance as a useful staging procedure because it is minimally invasive and spares approximately 70-80% of the patients a more extensive axillary lymph node dissection. The evolving techniques for selective SLN dissection using blue dye and radiotracer methods are reviewed in this article. Based on the classic definition of the breast lymphatic drainage and recently published articles addressing the issue of peritumoral and intradermal injections, a possible new and simplified approach using intradermal injection may identify the axillary SLN more quickly and reliably. This article emphasizes the importance of a multidisciplinary approach in the identification of SLNs by preoperative lymphoscintigraphy performed by expert nuclear medicine physicians, the intraoperative mapping and harvesting of SLNs by well trained surgeons and the meticulous examination of SLNs by experienced pathologists. Therefore, to achieve the highest rate of accuracy regarding SLN status, it is imperative that a multidisciplinary team with close communication and cooperation be formed. The clinical significance of SLNs will be determined by results from follow-up and clinical trials.

Breast Neoplasms↗
PubMed2000

Pathologic analysis of the sentinel lymph node.

The development of the sentinel lymph node concept has had a revolutionary effect on the way radical cancer surgery is viewed. The selective excision of the sentinel node alone has been proposed as an alternative to complete regional lymphadenectomy. This article addresses the sentinel lymph node hypothesis and the role of pathologic analysis, radiation safety, intraoperative and postoperative assessment, pathologic analysis in prognosis, and polymerase chain reaction-based studies.

Breast Neoplasms↗
PubMed2000

Is familial non-medullary thyroid carcinoma more aggressive than sporadic thyroid cancer? A multicenter series.

BACKGROUND: The aggressiveness of familial non-medullary thyroid cancer (FNMTC) has been a subject of debate. The purpose of the study was to determine whether FNMTC is more aggressive than sporadic thyroid cancer. METHODS: A multicenter retrospective matched-case control study of FNMTC versus sporadic non-medullary thyroid cancer was conducted. Disease-free survival (time to recurrence) for both groups was compared. RESULTS: Forty-eight familial cases were compared with 144 age-, gender-, and stage-matched controls. Patients with FNMTC had a significantly shorter disease-free survival compared with sporadic non medullary thyroid cancer. Patients with FNMTC who presented with evidence of distant metastasis, or who were from families with more than 2 thyroid cancer-affected members, had the worst prognosis. The available staging systems were less likely to predict the outcome in patients with FNMTC than in patients with sporadic non-medullary thyroid cancer unless one accounted for the strength of family history in the staging system. CONCLUSIONS: FNMTC is more aggressive than sporadic non-medullary thyroid cancer. The best predictors of a poor outcome in patients with FNMTC are the number of family members affected by thyroid cancer and evidence of distant metastasis.

Adult↗
PubMed2000

The helix-loop-helix transcription factor, Id-1, is overexpressed in medullary thyroid cancer.

BACKGROUND: The Id-1 helix-loop-helix protein inhibits differentiation and enhances cell proliferation. It is required for cell cycle progression. The Id-1 gene is highly expressed in a variety of tumor-derived cell lines. It increases after mitogen stimulation and is overexpressed in some human neoplasms. Therefore, we hypothesized that the Id-1 gene may play a role in medullary thyroid carcinogenesis. METHODS: The expression of the Id-1 protein in human medullary thyroid cancer (MTC) and the corresponding normal thyroid tissue was determined by Id-1 immunohistochemistry. In a human MTC cell line (TT), the effects of growth stimulation and redifferentiation on Id-1 expression were determined by Northern blot analysis. RESULTS: Id-1 immunostaining intensity in 9 MTC samples (6 sporadic, 2 familial, and 1 MEN 2A) was moderate to strong. However, it was absent or faint in the corresponding normal thyroid tissue. The Id-1 protein was significantly overexpressed in MTC compared with corresponding normal thyroid tissue on the basis of the percentage of positive cells and immunostaining intensity (P =.002). In the TT cell line, Id-1 messenger RNA (mRNA) expression was increased 4-fold after growth stimulation with serum. Phorbol ester (which induces redifferentiation in the TT cell line) downregulated Id-1 mRNA expression. CONCLUSIONS: Id-1 is overexpressed in MTC. The Id-1 gene may play a role in the regulation of MTC differentiation and proliferation.

Adult↗
PubMed1999

A Val 677 activating mutation of the thyrotropin receptor in a Hürthle cell thyroid carcinoma associated with thyrotoxicosis.

Thyroid nodules presenting as hot at 131I-scintigraphy are usually benign follicular adenomas. We report a 42-year-old female patient with an autonomously functioning Hürthle cell thyroid carcinoma causing thyrotoxicosis. Genetic analysis of her thyroid tumoral DNA revealed a heterozygotic activating mutation of the thyrotropin receptor (TSHR) gene that was located downstream to all of the other genetic alterations currently identified, and is due to a base substitution at codon 677 (normal cytosine replaced by guanine, CTG for GTG causing leucine substitution by valine in the seventh transmembrane domain of the receptor). This mutation was detected in the tumor, but not in the leucocytes from the same patient. The Val 677-TSHR mutant showed constitutive activity, in terms of cyclic adenosine monophosphate (cAMP) production, when permanently transfected in Chinese hamster ovary (CHO) cells. Gsp and ras oncogenes and the p53 tumor suppressor gene were not present in the Hürthle cell cancer. The TSHR mutation in this Hürthle cell carcinoma may be responsible for maintaining differentiated thyroid function and hyperthyroidism.

Adenocarcinoma↗
PubMed1997

Prognostic factors in thyroid carcinoma.

Thyroid carcinomas range from the most indolent to the most aggressive human malignancies. A variety of clinical and pathologic factors can be used to help predict behavior and determine appropriate therapy. New molecular biologic techniques show promise in further refining the assessment of prognosis in thyroid cancer patients.

Biomarkers, Tumor↗
PubMed1996

Postarthroplasty histiocytic lymphadenopathy in gynecologic oncology patients. A benign reactive process that clinically may be mistaken for cancer.

BACKGROUND: A distinctive histiocytosis occurs in the regional draining lymph nodes after large joint replacements, resulting in lymphadenopathy that may mimic cancer both grossly and microscopically. Postarthroplasty histiocytic lymphadenopathy has most often been observed in males during surgery for prostate cancer. METHODS: The authors present three examples of postarthroplasty histiocytic lymphadenopathy that occurred in gynecologic oncology patients. We studied the clinical, histologic, and immunohistochemical features of all three cases and the ultrastructure of one of them. RESULTS: Most involved lymph nodes were enlarged, but histiocytosis was also seen in normal sized lymph nodes. Microscopically, histiocytes with abundant granular cytoplasm were present in the lymph node parenchyma, and, to a lesser extent, in the sinuses. Normal lymph node architecture was variably effaced and the histiocytic infiltrate extended focally into the perinodal tissue. Small, black metal particles were present in the histiocytes in every case. Birefringent polyethylene particles were a prominent finding in all three cases as confirmed by positive modified oil red O staining, and, in one case, by electron microscopy. The histiocytes were strongly immunoreactive for CD68, but immunostains for S100 protein, MAC 387, and cytokeratin were negative. CONCLUSIONS: Enlargement of the lymph nodes in cancer patients who have had large joint replacements may be due to a benign histiocytosis rather than to metastatic cancer. The histologic features of the lymphadenopathy are distinctive and recognizable in routine histologic preparations. Polyethylene wear particles shed from joint prostheses are the most common substances in the histiocytes and are the most likely cause of the histiocytosis.

Aged↗
PubMed1991

Chronic myelomonocytic leukemia transformation in polycythemia vera.

Myelodysplasia is an increasingly recognized complication of polycythemia vera (PCV) which often precedes leukemic transformation. This paper describes two patients with aggressive chronic myelomonocytic leukemia, previously undescribed as a complication of PCV. Both patients presented with rapidly increasing splenomegaly which was resistant to treatment with hydroxyurea and external beam irradiation. Splenectomy precipitated fatal hepatic failure in one patient. The other died shortly after transformation to acute myelomonocytic leukemia (FAB M4 classification). Pathology of the bone marrow, spleen, and liver was remarkable for extensive infiltration by dysplastic myeloid elements. Survival was short, only 4-6 months from diagnosis. The unique characteristics in these patients were: (i) prior history of PCV; (ii) rapidly increasing splenomegaly resistant to standard therapy; (iii) absence of overt marrow fibrosis; (iv) hypercellularity (greater than or equal to 90% cellular) of the bone marrow with dysplasia in the myeloid, erythroid, and megakaryocytic cell lines; (v) peripheral monocytosis greater than 1 x 10(9); and (vi) extensive infiltration of the spleen and liver by dysplastic myeloid cells. In addition, the patient who subsequently developed acute leukemia had been treated with hydroxyurea under the PVSG-08 protocol, providing further evidence of the potential leukemogenic effects of this agent.

Aged↗
PubMed1989

Leaflet entrapment causing acute severe aortic insufficiency during balloon aortic valvuloplasty.

Cusp entrapment is a previously unreported mechanism of aortic insufficiency after balloon aortic valvuloplasty. In a patient who developed severe acute aortic insufficiency and expired after balloon aortic valvuloplasty, pathologic evaluation revealed a large, solitary, fractured, calcific nodule in the noncoronary cusp in which the malaligned, irregular fracture surfaces of the nodule had entrapped the leaflet in an open position. The ease with which the entrapped leaflet was reduced by manipulation on postmortem examination suggests that further manipulation of the cusp might restore valve competence in some cases when aortic insufficiency occurs after balloon valvuloplasty in calcific aortic stenosis.

Aged↗
PubMed1986

The relative immunogenicity of corneal epithelium, stroma, and endothelium. The role of major histocompatibility complex antigens.

Corneal allografts have been shown to give rise to immune responses, but the role and relative importance of individual corneal cell populations in evoking such responses remain unclear. We dissected ACI (RT1a) rat corneas into separate epithelial, stromal, and endothelial components by a method that yields pure cell populations in tissue culture, and grafted these components separately to groups of fully allogeneic PVG (RT1c) recipients). Grafts of corneal stroma elicited strong cellular cytotoxic immune responses in a cell-mediated lymphocytotoxic assay, but corneal epithelium failed to generate any detectable response. Grafts of corneal endothelium alone, however, evoked a potent cellular cytotoxic response. Using congenic rats, it was found that grafts from PVG.1A (RT1a) donors to PVG (RT1c) recipients (which differ at both the RT1.A and B loci) yielded identical results. However, no corneal component graft from PVG.R1 (RT1rl) donors to PVG recipients (which differ only at RT1.A) generated a detectable immune response. Use of target lymphoblasts from congenic strains established that at least part of all responses detected were directed against class I (RT1.A) major histocompatibility complex antigens. These findings indicate that there is differential immunogenicity of specific corneal tissue components in the rat that may be further influenced by the degree of MHC disparity between donor and recipient.

Animals↗