Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Medicina (Kaunas) ; 54(6)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513999

RESUMO

A simple solution may exist for both the problem of sudden dementia and confusion after surgery in the elderly and the bimodal relapse pattern among breast cancer patients who were treated with a mastectomy. Systemic inflammation by a variety of mechanisms can induce tumor outgrowth from dormant states, such as single dormant cells and avascular micrometastases. This may also explain sudden confusion and dementia for the elderly after surgery. We propose that surgery-induced inflammation may be addressed by "protective anesthesia". We suggest ketorolac for 4 days starting at the time of surgery to prevent early relapse in breast and probably other cancers; perhaps that or something similar could be used before surgery in elderly patients to prevent post-operative cognitive dysfunction.


Assuntos
Neoplasias da Mama/cirurgia , Confusão/etnologia , Demência/epidemiologia , Mastectomia/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Inflamação/tratamento farmacológico , Interleucina-6/sangue , Cetorolaco/uso terapêutico , Camundongos , Recidiva Local de Neoplasia/patologia , Complicações Pós-Operatórias/prevenção & controle
2.
BMC Cancer ; 9: 7, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19133151

RESUMO

BACKGROUND: Women with Down syndrome very rarely develop breast cancer even though they now live to an age when it normally occurs. This may be related to the fact that Down syndrome persons have an additional copy of chromosome 21 where the gene that codes for the antiangiogenic protein Endostatin is located. Can this information lead to a primary antiangiogenic therapy for early stage breast cancer that indefinitely prolongs remission? A key question that arises is when is the initial angiogenic switch thrown in micrometastases? We have conjectured that avascular micrometastases are dormant and relatively stable if undisturbed but that for some patients angiogenesis is precipitated by surgery. We also proposed that angiogenesis of micrometastases very rarely occurs before surgical removal of the primary tumor. If that is so, it seems possible that we could suggest a primary antiangiogenic therapy but the problem then arises that starting a therapy before surgery would interfere with wound healing. RESULTS: The therapy must be initiated at least one day prior to surgical removal of the primary tumor and kept at a Down syndrome level perhaps indefinitely. That means the drug must have virtually no toxicity and not interfere meaningfully with wound healing. This specifically excludes drugs that significantly inhibit the VEGF pathway since that is important for wound healing and because these agents have some toxicity. Endostatin is apparently non-toxic and does not significantly interfere with wound healing since Down syndrome patients have no abnormal wound healing problems. CONCLUSION: We propose a therapy for early stage breast cancer consisting of Endostatin at or above Down syndrome levels starting at least one day before surgery and continuing at that level. This should prevent micrometastatic angiogenesis resulting from surgery or at any time later. Adjuvant chemotherapy or hormone therapy should not be necessary. This can be continued indefinitely since there is no acquired resistance that develops, as happens in most cancer therapies.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Simulação por Computador , Endostatinas/administração & dosagem , Neovascularização Patológica/prevenção & controle , Pré-Medicação , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Síndrome de Down/genética , Endostatinas/genética , Feminino , Humanos , Modelos Biológicos , Neovascularização Patológica/genética , Cicatrização/efeitos dos fármacos
3.
Breast Cancer Res ; 10(5): R83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18844974

RESUMO

INTRODUCTION: The dynamics of breast cancer recurrence and death, indicating a bimodal hazard rate pattern, has been confirmed in various databases. A few explanations have been suggested to help interpret this finding, assuming that each peak is generated by clustering of similar recurrences and different peaks result from distinct categories of recurrence. METHODS: The recurrence dynamics was analysed in a series of 1526 patients undergoing conservative surgery at the National Cancer Institute of Milan, Italy, for whom the site of first recurrence was recorded. The study was focused on the first clinically relevant event occurring during the follow up (ie, local recurrence, distant metastasis, contralateral breast cancer, second primary tumour), the dynamics of which was studied by estimating the specific hazard rate. RESULTS: The hazard rate for any recurrence (including both local and distant disease relapses) displayed a bimodal pattern with a first surge peaking at about 24 months and a second peak at almost 60 months. The same pattern was observed when the whole recurrence risk was split into the risk of local recurrence and the risk of distant metastasis. However, the hazard rate curves for both contralateral breast tumours and second primary tumours revealed a uniform course at an almost constant level. When patients with distant metastases were grouped by site of recurrence (soft tissue, bone, lung or liver or central nervous system), the corresponding hazard rate curves displayed the typical bimodal pattern with a first peak at about 24 months and a later peak at about 60 months. CONCLUSIONS: The bimodal dynamics for early stage breast cancer recurrence is again confirmed, providing support to the proposed tumour-dormancy-based model. The recurrence dynamics does not depend on the site of metastasis indicating that the timing of recurrences is generated by factors influencing the metastatic development regardless of the seeded organ. This finding supports the view that the disease course after surgical removal of the primary tumour follows a common pathway with well-defined steps and that the recurrence risk pattern results from inherent features of the metastasis development process, which are apparently attributable to tumour cells.


Assuntos
Neoplasias da Mama/epidemiologia , Metástase Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Tábuas de Vida , Pessoa de Meia-Idade , Modelos Biológicos , Metástase Neoplásica/fisiopatologia , Recidiva Local de Neoplasia/fisiopatologia , Segunda Neoplasia Primária/fisiopatologia , Especificidade de Órgãos , Modelos de Riscos Proporcionais
4.
Nat Clin Pract Oncol ; 4(12): 699-710, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18037874

RESUMO

Primary tumor removal, usually considered intrinsically beneficial, can perturb metastatic homeostasis, and for some patients results in the acceleration of metastatic cancer. The continuous-growth model is required to yield to an interrupted-growth model, the implications of which are episodes of tumor dormancy. This Review analyzes the recent evolution of two paradigms related to the development of breast cancer metastases. The evolution of the paradigms described herein is supported by a growing body of findings from experimental models, and is required to explain breast cancer recurrence dynamics for patients undergoing surgery with or without adjuvant chemotherapy.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Mastectomia/efeitos adversos , Quimioterapia Adjuvante , Humanos , Modelos Biológicos , Metástase Neoplásica/fisiopatologia , Metástase Neoplásica/prevenção & controle , Processos Neoplásicos , Recidiva
5.
J Clin Oncol ; 22(1): 102-7, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14701771

RESUMO

PURPOSE: To provide data relevant to the paradoxical mortality excess for women age 40 to 49 years observed during the first 6 to 8 years in the invited group in all mammography screening studies. PATIENTS AND METHODS: In 1,173 patients undergoing mastectomy alone as primary treatment, allocated to subsets according to menopausal status and tumor size, hazard rates for death were calculated. The ratios between the hazard rate for T2-T3 patients and the corresponding value for T1 patients were assessed over time. RESULTS: For postmenopausal patients, the ratio appeared to be time-dependent, dropping from the maximum value of approximately 5 at the first year after surgery to a near constant value of approximately 2 after 5 to 6 years. Premenopausal patients, on the contrary, showed a nearly constant ratio of approximately 3. Therefore, although in each T-category the 10-year survival of premenopausal and postmenopausal patients was similar, its time distribution was menopause-dependent. In particular, the difference between cumulative survival of premenopausal and postmenopausal T2-T3 patients attained statistical significance after 3 years. CONCLUSION: The mortality reduction due to the diagnosis of smaller tumors is significantly higher for postmenopausal women than for premenopausal women during early postsurgery time. According to the hypothesis that primary tumor surgical removal, occurring sooner in the invited group than in the control arm of screening trials, results in some acceleration of metastasis development, a greater number of unfavorable events (recurrence and death) should occur in the invited group. We suggest that for younger women, the early balance between benefit from tumor downsizing and harm from surgery-induced metastasis acceleration results in harm. This disadvantage does not occur in postmenopausal women.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/mortalidade , Mamografia , Programas de Rastreamento , Menopausa , Estadiamento de Neoplasias , Adulto , Fatores Etários , Neoplasias da Mama/cirurgia , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Mastectomia , Pessoa de Meia-Idade , Metástase Neoplásica , Fatores de Risco
6.
Breast Cancer Res ; 6(6): R689-96, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15535851

RESUMO

INTRODUCTION: Information on the metastasis process in breast cancer patients undergoing primary tumour removal may be extracted from an analysis of the timing of clinical recurrence. METHODS: The hazard rate for local-regional and/or distant recurrence as the first event during the first 4 years after surgery was studied in 1173 patients undergoing mastectomy alone as primary treatment for operable breast cancer. Subset analyses were performed according to tumour size, axillary nodal status and menopausal status. RESULTS: A sharp two-peaked hazard function was observed for node-positive pre-menopausal patients, whereas results from node-positive post-menopausal women always displayed a single broad peak. The first narrow peak among pre-menopausal women showed a very steep rise to a maximum about 8-10 months after mastectomy. The second peak was considerably broader, reaching its maximum at 28-30 months. Post-menopausal patients displayed a wide, nearly symmetrical peak with maximum risk at about 18-20 months. Peaks displayed increasing height with increasing axillary lymph node involvement. No multi-peaked pattern was evident for either pre-menopausal or post-menopausal node-negative patients; however, this finding should be considered cautiously because of the limited number of events. Tumour size influenced recurrence risk but not its timing. Findings resulting from the different subsets of patients were remarkably coherent and each observed peak maintained the same position on the time axis in all analysed subsets. CONCLUSIONS: The risk of early recurrence for node positive patients is dependent on menopausal status. The amount of axillary nodal involvement and the tumour size modulate the risk value at any given time. For pre-menopausal node-positive patients, the abrupt increase of the first narrow peak of the recurrence risk suggests a triggering event that synchronises early risk. We suggest that this event is the surgical removal of the primary tumour. The later, broader, more symmetrical risk peaks indicate that some features of the corresponding metastatic development may present stochastic traits. A metastasis development model incorporating tumour dormancy in specific micro-metastatic phases, stochastic transitions between them and sudden acceleration of the metastatic process by surgery can explain these risk dynamics.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Pós-Menopausa , Pré-Menopausa , Modelos de Riscos Proporcionais , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Simulação por Computador , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
9.
Int J Surg ; 5(5): 300-4, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17933694

RESUMO

There is excess breast cancer mortality for African-Americans (AA) compared to European-Americans (EA) of 1.5-2.2 fold that first appeared in 1970s and has been worsening since. This disparity may not be explained solely by reduced access to medical care. We proposed that surgery to remove a primary tumor induces angiogenesis of distant dormant micrometastases in 20% of premenopausal node-positive patients. This hypothesis helps explain the reduced benefit of mammography for women aged 40-49. Interestingly, for AA the average age at diagnosis is 46 while for EA it is 57. The resultant increased proportion of AA premenopausal breast cancer suggests a possible explanation for the AA/EA excess mortality. Early detection, which began in the 1970s, is more effective in postmenopausal women than in premenopausal women. Since AA breast cancer is mostly premenopausal and EA breast cancer is mostly postmenopausal, it might be anticipated that starting in the 1970s because of surgery-induced early mortality, outcome would be superior for EA compared to AA.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/fisiopatologia , Mama/patologia , Neovascularização Patológica/etnologia , Neovascularização Patológica/fisiopatologia , Adulto , Negro ou Afro-Americano , Biópsia/efeitos adversos , Mama/cirurgia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Neovascularização Patológica/etiologia , Pós-Menopausa , Pré-Menopausa , População Branca
10.
Cancer ; 110(9): 1880-8, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17876835

RESUMO

Since the 1970s, overall age-adjusted breast cancer mortality rates in the U.S. have been higher among African American (AA) women than among Caucasian American (CA) women. The racial disparity is not fully explainable based on socioeconomic factors. Suspected biologic factors underlying this trend may be interpreted by both epidemiologic and clinical perspectives. Descriptive epidemiologic studies suggest that breast cancer may be a mixture of at least 2 main diseases and/or causal pathways. The first breast cancer is early-onset, with peak incidence near age 50 years and generally more aggressive outcome. The second breast cancer is late-onset, with peak incidence near age 70 years and more indolent course. The early-onset type of breast cancer is overrepresented among AA women compared with CA women. Clinical studies suggest that the course of breast cancer may be characterized by a common pathway through sequential dormant and active states eventually resulting in clustered appearance of clinical metastases. A balance between tumor and host traits influences the pace of the common pathway. Therefore, the recurrence risk profile of a single patient is seemingly determined by a specific mix of hierarchical prognostic factors, resulting from the unique genetic, environmental, or behavioral traits of that individual, which may be affected by race-related factors. We suggest that the components of the AA versus CA disparity not attributable to socioeconomic factors are a particular case of the more general issue of host-tumor interaction and that epidemiologic and clinical views are complementary; each is observing biologic parameters, which are not completely captured by the other. A 'unifying hypothesis' incorporating findings from genetics, epidemiology, and clinical studies should be aggressively pursued.


Assuntos
Negro ou Afro-Americano/etnologia , Neoplasias da Mama/etnologia , Modelos Biológicos , População Branca/etnologia , Animais , Feminino , Humanos , Fatores de Risco , Fatores Socioeconômicos , Resultado do Tratamento
11.
J Clin Oncol ; 24(27): 4391-6, 2006 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-16926222

RESUMO

PURPOSE: To find a quantitative relationship between tumor size and frequency of axillary lymph node involvement. PATIENTS AND METHODS: The frequency of axillary node involvement versus primary tumor volume was analyzed in 10 selected series of patients incorporating a total of 57,244 women with resectable breast cancer. The average number of events per unit volume resulting in tumor spread to axillary lymph nodes before tumor surgical removal Theta(V)/V, was estimated under simple probabilistic assumptions. RESULTS: The allometric scaling law Theta(V)/V = 0.0586V(-0.7457) was estimated on the data, fitting the proportion of lymph node involvement on tumor volume V (in microliters). The estimate 0.7457 (95% CI, 0.7200 to 0.7713) suggests that the true scaling exponent, under the assumed model, may be the fractional value, which characterizes scaling relationships for a wide variety of biologic variables at both the whole organism level and organ level. CONCLUSION: Results suggest that the phenomenon should be related to some internal structural trait of the tumor. The vascular network seems to be the best candidate. This result does not support a mere mechanical model of lymphatic tumor spread. A more complex biology-based model of lymphohematogenous spread is suggested, in which the axillary nodes draining the lymph from the primary tumor may become activated by factors produced by both tumor cells and tumor stroma, thus favoring cell-selective homing of otherwise circulating tumor cells. The success of fractal features related to the internal architecture brings additional support to the consideration of primary breast cancer as an organ-like structure.


Assuntos
Biometria , Neoplasias da Mama/patologia , Linfonodos/patologia , Axila , Neoplasias da Mama/cirurgia , Feminino , Humanos , Incidência , Linfonodos/cirurgia , Metástase Linfática , Computação Matemática , Modelos Biológicos , Modelos Estatísticos , Células Neoplásicas Circulantes , Biópsia de Linfonodo Sentinela
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA