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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2003-2006, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018396

RESUMO

Breast-conserving surgery, also known as lumpectomy, is an early stage breast cancer treatment that aims to spare as much healthy breast tissue as possible. A risk associated with lumpectomy is the presence of cancer positive margins post operation. Surgical navigation has been shown to reduce cancer positive margins but requires manual segmentation of the tumor intraoperatively. In this paper, we propose an end-to-end solution for automatic contouring of breast tumor from intraoperative ultrasound images using two convolutional neural network architectures, the U-Net and residual U-Net. The networks are trained on annotated intraoperative breast ultrasound images and evaluated on the quality of predicted segmentations. This work brings us one step closer to providing surgeons with an automated surgical navigation system that helps reduce cancer-positive margins during lumpectomy.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Redes Neurais de Computação , Ultrassonografia Mamária
2.
J Surg Oncol ; 95(7): 546-54, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17219388

RESUMO

BACKGROUND: The clinical relevance of RT-PCR positivity for melanoma markers in the sentinel node remains controversial. Our purpose was to determine whether patients with a histologically negative but RT-PCR positive node were at an increased risk for recurrence than their RT-PCR negative counterparts. METHODS: Thirty-nine adult patients underwent sentinel node biopsies for melanoma between 1998 and 2000. Each sentinel node was bivalved. Half was serially sectioned and examined by routine hematoxylin and eosin (H&E) and immunohistochemistry (IHC; S100, HMB-45, melanA, and tyrosinase). The other half was analyzed by a nested RT-PCR assay for tyrosinase. RESULTS: Patients were followed for recurrence with a mean follow-up of 71.1 months. The odds ratio of recurrence for RT-PCR positive versus RT-PCR negative patients was 1.39 (0.34, 5.62; p = 0.73). Within the histology negative subgroups, the risk of recurrence in the RT-PCR positive group (26.7%) was not significantly different from the risk of recurrence in the RT-PCR negative group (22.2%) (p = 0.33 chi-squared). RT-PCR of the sentinel node was not a predictor for recurrence on multivariate analysis (p = 0.65). CONCLUSION: Sentinel node RT-PCR positivity did not risk stratify histologically negative melanoma patients beyond routine pathologic examination in this series.


Assuntos
Linfonodos/patologia , Melanoma/patologia , Recidiva Local de Neoplasia/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Melanoma/secundário , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Fatores de Risco
3.
Ann Surg Oncol ; 8(2): 133-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11258777

RESUMO

BACKGROUND: The optimal radioactive tracer and technique for sentinel lymph node localization in breast cancer is yet to be determined. The dilemma of small particle size with dispersion to second echelon nodes versus failure of migration of larger radiocolloids needs to be resolved. A new radiocolloid preparation with particle size under 0.1 micron was developed with excellent primary/post lymphatic entrapment ratio. OBJECTIVE: To assess the feasibility of a new 99mTc radiocolloid cysteine-rhenium colloid in sentinel lymph node (SLN) localization for breast cancer. METHODS: Forty-seven patients with newly diagnosed T1 or T2 breast cancer underwent injection of 99mTc-labeled cysteine-rhenium colloid followed by lymphoscintigraphy. Same day SLN biopsy with patent blue dye and intraoperative gamma probe to identify SLNs were performed. RESULTS: SLN mapping and intraoperative localization were successful in 46/47 (98%) of patients. The blue dye radioactive tracer concordance was 94%. There was one false-negative in a patient with a nonpalpable tumor that underwent ultrasound-guided peritumoral radiocolloid injection. CONCLUSIONS: 99mTc-cysteine-rhenium colloid is highly effective in identifying SLNs. It has the advantage of smaller particle size than sulfur colloid with easier lymphatic migration. It has a more neutral pH with less pain on injection and does not require filtration, thereby minimizing radiation exposure to technologists.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Cisteína , Compostos de Organotecnécio/uso terapêutico , Biópsia de Linfonodo Sentinela/métodos , Animais , Axila , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Corantes/administração & dosagem , Cisteína/análogos & derivados , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Estudos Prospectivos , Coelhos , Cintilografia , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade
4.
Ann Plast Surg ; 45(5): 491-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11092358

RESUMO

Nodal metastases in patients with melanoma identify a reduction of survival by 50%; however, elective lymph node dissection (ELND) has not been shown clearly to improve survival. Morton's technique of sentinel node biopsy, using preoperative lymphoscintigraphy and intraoperative blue dye, addresses elegantly the controversy regarding ELND. Sentinel node biopsy has been shown to stage the patient accurately because metastases from melanoma follow an orderly progression from the sentinel node to the remainder of the basin. Fifty-six consecutive patients with American Joint Committee on Cancer stage 1b or 2 melanoma seen at the London Health Sciences Center between July 1998 and January 2000 were enrolled prospectively to undergo sentinel node biopsy. Preoperative lymphoscintigraphy was conducted in the nuclear medicine department. A total of 10 to 15 MBq (0.27-0.41 mCi) of technetium 99m (99mTc) rhenium colloid or filtered sulfur colloid was injected intradermally around the biopsy scar. Images were obtained to localize all draining nodal basins. The location of the sentinel node was marked on the skin. The patient was taken to the operating room and anesthetized. Isosulfan blue dye was injected intradermally around the biopsy scar. A hand-held gamma probe was used intraoperatively as a guide to the first draining node. Blue-stained lymphatic channels aided in the dissection. Sentinel node localization was successful in 55 of 56 patients, for an overall success rate of 98%. Preoperative lymphoscintigraphy identified a sentinel node in an unpredictable location in 32% of patients. On average, 2.3 sentinel nodes per patient were identified on the initial scan, and 2.2 sentinel nodes per patient were recovered at surgery. Both 99mTc rhenium and filtered sulfur colloid showed no substantial differences in tracer uptake and retention in the sentinel node. Twelve patients had a positive sentinel node on routine histology, and 11 patients subsequently underwent completion lymphadenectomy. The mean thickness of the primary melanoma in the 12 patients with positive sentinel nodes was 3.7 mm compared with a mean tumor thickness of 1.8 mm in the remaining 41 patients with negative biopsies (p = 0.0003). Two patients experienced recurrence in a regional basin after negative pathological evaluation of the sentinel node. Reverse transcription-polymerase chain reaction analysis of both of these patients was positive. Two patients are alive with metastatic disease and 54 patients are alive without disease, with a mean follow-up of 1 year (range, 2-24 months). Complications occurred at a substantially higher rate (45%) after completion lymphadenectomy than after sentinel node biopsy alone (9%). Sentinel node biopsy is a feasible technique with a high success rate (98%), but it requires a multidisciplinary approach. This study validates the clinical usefulness of 99mTc rhenium colloid for lymphoscintigraphy.


Assuntos
Melanoma/patologia , Compostos Radiofarmacêuticos , Rênio , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia , Compostos de Tecnécio , Adulto , Idoso , Feminino , Humanos , Londres , Excisão de Linfonodo , Masculino , Melanoma/cirurgia , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias Cutâneas/cirurgia , Coloide de Enxofre Marcado com Tecnécio Tc 99m
5.
Cancer Genet Cytogenet ; 118(1): 35-41, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10731588

RESUMO

Jumping translocation is a rare cytogenetic aberration in leukemia and lymphoma, and its etiologic mechanisms are not clearly known. We report two cases with jumping translocations. One had follicular lymphoma and jumping translocations of 1q onto the telomeric regions of 5p, 9p, and 15q in three cell lines, co-existing with the specific translocation t(14;18)(q32;q21). The second case had acute myeloid leukemia (AML) and jumping translocations of 11q as the sole aberration, onto multiple derivative chromosomes in each of the abnormal cells. A total of 17 telomeric regions were seen as the recipients of 11q in this case, and 9q was always involved as one of the recipients in all abnormal cells. Fluorescence in situ hybridization (FISH) confirmed the identification of 11q material in the derivative chromosomes. While 1q has been the most common donor of acquired jumping translocations, this is the first report on jumping translocations of 11q. Different from all previously reported jumping translocations which involve only one recipient in each cell line and lead to a mosaic trisomy, multiple recipients in most of the abnormal cells in this case had led to a tetrasomy, or a pentasomy of 11q. The pattern of chromosome involvement as the recipients of 11q appears to show a continuing evolutionary process of jumping, stabilization, and spreading of the donor material into other chromosomes. Somatic recombinations between the interstitial telomeric or subtelomeric sequences of a derivative chromosome and the telomeric sequences of normal chromosomes are believed to be the underlying mechanism of jumping translocations and their clonal evolution.


Assuntos
Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 1/genética , Leucemia Mieloide/genética , Linfoma Folicular/genética , Translocação Genética/genética , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneuploidia , Coloração Cromossômica , Feminino , Humanos , Cariotipagem , Masculino , Telômero/genética
6.
Int J Radiat Oncol Biol Phys ; 42(2): 319-24, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9788410

RESUMO

BACKGROUND AND PURPOSE: To determine the percentage of complete responders and the resectability rate for patients with locally advanced carcinoma of the rectum treated by 5-fluorouracil (5-FU) infusional chemotherapy and pelvic radiation. MATERIALS AND METHODS: Between October 1992 and June 1996, 29 patients with a diagnosis of locally advanced unresectable rectal cancer received preoperative 5 FU by continuous intravenous infusion at a dose of 225 mg/m2/day concurrent with pelvic radiation (median 54 Gy/28 fractions). All patients were clinical stage T4 on the bases of organ invasion or tumor fixation. Median time for surgical resection was 6 weeks. RESULTS: Median follow-up for the group was 28 months (range 5-57 months). Six patients were felt to be persistently unresectable or developed distant metastases and did not undergo surgical resection. Of the 29 patients, 23 proceeded to surgery, 18 were resectable for cure, 13 by abdominoperineal resection, 3 by anterior resection and 2 by local excision. Of the 29 patients, 4 (13%) had a complete response, and 90% were clinically downstaged. Of the 18 resected patients, 1 has died of his disease, 17 are alive, and 15 disease-free. The regimen was well tolerated; there was only one treatment-related complication, a wound dehiscence. CONCLUSION: The combination of 5 FU infusion and pelvic radiation in the management of locally advanced rectal cancer is well tolerated and provides a baseline for comparison purposes with future combinations of newer systemic agents and radiation.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Antimetabólitos Antineoplásicos/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia
7.
Am J Surg Pathol ; 20(10): 1260-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8827033

RESUMO

Tumor angiogenesis is associated with metastasis in several types of solid tumors, including melanoma, breast, prostate, lung, bladder, and oral-cavity tumors. The purpose of this study was to determine whether tumor angiogenesis could predict recurrence following curative surgery for colorectal cancer. Thirty-five patients were studied, including 13 patients with recurrent tumor and 22 without. Representative formalin-fixed, paraffin-embedded sections of invasive colorectal cancers from these patients were sectioned. The endothelial cells of microvessels within the tumors were highlighted by immunohistochemical staining for CD31. The most active areas were identified and the microvessels counted in a x 400 field (0.152 mm2) by two observers in a blinded fashion. Tumor microvessel count (p = 0.0062). Dukes' staging (p = 0.0004), vascular invasion (p = 0.0280), and tumor grade (p = 0.0559) were all significantly associated with tumor recurrence. Tumor microvessel counts > or = 65 per x 400 field were associated with tumor recurrence (p = 0.0035, relative risk [RR] = 11.3). Controlling for Dukes' stage, a multivariate logistic regression model revealed that a tumor microvessel count > or = 65 is an important predictor of tumor recurrence (p = 0.0783, RR = 6.0). A backwards elimination proportional hazards model revealed that a microvessel count > or = 65 shows a trend toward independent prediction of time to tumor recurrence (p = 0.1203, RR = 2.967) when controlled for Dukes' staging (p = 0.0029, RR = 9.089). Despite the small number of patients studied, these results suggest that the number of microvessels in sections of invasive colorectal adenocarcinoma immunohistochemically stained with CD31 may be an important independent predictor of tumor recurrence and time to recurrence.


Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/patologia , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/patologia , Recidiva Local de Neoplasia/patologia , Neovascularização Patológica/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Incidência , Masculino , Microcirculação/patologia , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida
8.
Gastroenterology ; 107(3): 847-53, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8076771

RESUMO

BACKGROUND/AIMS: Truncal vagotomy causes gallbladder dilatation and possibly cholelithiasis. During liver transplantation, when the gallbladder is transplanted with the donor liver, the gallbladder and liver are extrinsically denervated. The aim of this study was to determine whether extrinsic denervation affects gallbladder volume and postprandial emptying. METHODS: To evaluate fasting gallbladder volume, 26 transplant recipients underwent ultrasonography. Twenty-eight normal volunteers were controls. To evaluate postprandial contractility, seven transplant recipients underwent radionuclide gallbladder-emptying studies. Gastric emptying and cholecystokinin release were simultaneously determined after a fatty meal to exclude a difference in gallbladder stimulus. Sixteen normal volunteers were controls. RESULTS: There were no differences in fasting gallbladder volume or postprandial contractility, gastric emptying, and cholecystokinin release between transplant patients and controls. Median fasting and postprandial gallbladder volumes for the transplant recipients (95% confidence) were 16 mL (12-34 mL) and 3 mL (0-8 mL), respectively, and for controls were 18 mL (13-21 mL; P = 0.73) and 3 mL (1-6 mL; P = 0.97), respectively. CONCLUSIONS: These data do not show gallbladder dilatation or impaired postprandial gallbladder contraction in the extrinsically denervated gallbladder. This finding suggests that gallbladder dilatation may be caused by the unopposed activity of the sympathetic system after truncal vagotomy.


Assuntos
Ingestão de Alimentos , Jejum , Vesícula Biliar/inervação , Vesícula Biliar/fisiologia , Transplante de Fígado , Adulto , Colecistocinina/sangue , Denervação , Feminino , Vesícula Biliar/diagnóstico por imagem , Esvaziamento Gástrico , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Valores de Referência , Estômago/diagnóstico por imagem , Doadores de Tecidos
11.
Can J Surg ; 34(5): 477-80, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1655199

RESUMO

The authors report the case of a 21-year-old man who had malignant transformation within an eccrine spiradenoma involving the big toe. Although benign eccrine spiradenoma is not an uncommon cutaneous adnexal tumour, malignant change in this tumour is rare. To the authors' knowledge only 16 cases have been reported previously. Two histologically distinct components were seen in the tumour: typical eccrine spiradenoma, constituting a small part of the tumour, and carcinoma with areas of transition. The patient was treated by below-knee amputation and superficial inguinal node dissection. There was no evidence of recurrence 2 years after surgery.


Assuntos
Adenoma de Glândula Sudorípara/patologia , Carcinoma/patologia , Glândulas Écrinas/patologia , Neoplasias das Glândulas Sudoríparas/patologia , Adulto , Transformação Celular Neoplásica , Doenças do Pé/patologia , Humanos , Masculino , Dedos do Pé
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