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M J Lopez

Publications and source records attributed to M J Lopez.

At least 55 records · Page 3Linked to original sources
PubMed1993

Role of extended resection in the initial treatment of locally advanced colorectal carcinoma.

The focus of this review is the role of extended resection in the initial treatment of primary colorectal carcinoma. About 10% of patients with newly diagnosed colorectal cancer will have locally advanced disease without evident distant or discontiguous intraabdominal metastases. En bloc resection of such tumors, including attached tissues or organs, provides a 5-year survival rate of about 40%, if the microscopic margins are tumor free. As many as 60% of these large tumors are node negative; in this circumstance the 5-year survival rate approaches 70%. These results are achievable when there is a meticulous preoperative and intraoperative search for metastases, a wide anatomic resection, including en bloc lymphadenectomy, is performed, and tumor manipulation is minimized. Blunt separation of structures adherent to the primary tumor should be avoided because adhesions will be neoplastic in about 50% of cases, and cancer recurrence is virtually certain when tumor is transected. The mortality from multivisceral resection, including total pelvic exenteration, should be 10% or less. We emphasize the importance of including these patients in prospective trials to define their optimal adjuvant therapy. There is a disturbing recurring theme in published series, failure to extend the scope of resection in potentially curable patients. The management of these locally advanced lesions typically receives but cursory notice in otherwise highly detailed reviews or textbook chapters. In the present era of emerging multimodality treatment for colorectal cancer, the adequacy of the one most important treatment component--surgical resection--is seldom emphasized. Furthermore, our perusal of the recent literature disclosed no diminution in the incidence of inadequate resection, suggesting that this subject requires more emphasis in postgraduate surgical education.

Age Factors↗
PubMed1993

Indications for prophylactic mastectomy.

This article reviews the current state of knowledge regarding factors which put women at highest risk for developing breast cancer and identifies that population we consider as potential candidates for prophylactic mastectomy. Specifically, we focus on the concept of cumulative predisposition and the relative risk assigned to more significant factors that increase a woman's chances of developing breast cancer: family history, proliferative breast histology, and previous cancer in one breast. In addition to outlining the results of reconstruction, the article also examines the controversy surrounding the issue of whether any mastectomy can be truly prophylactic. We conclude with advice to physicians who must counsel women concerned about their breast cancer risk so they can help their patients make fully informed choices.

Adolescent↗
PubMed1992

Pathology and treatment of impalpable breast lesions.

With the increasing use of mammography, more needle-localized breast biopsies (NLBB) are being done. The purpose of this study was to analyze the pathology of impalpable breast lesions and the impact of NLBB on treatment strategies. From 1985 to 1990, 1,605 NLBB were performed, of which 321 (20%) were malignant. Twenty-five percent of malignant biopsies demonstrated in situ disease only. The average size of all lesions detected was 16 mm, and, for invasive cancer, 12 mm. Eighteen percent of invasive cancers had metastasized to the axillary lymph nodes. Surgical management consisted of mastectomy in 74% of patients and breast conservation treatment (BCT) in 26%. No significant difference in surgical management for women 50 years of age or younger compared with those older than 50 years of age was noted. Although the use of BCT for eligible women is recommended by the National Institutes of Health, it is not widely practiced, possibly reflecting less physician acceptance of BCT. These observations suggest that the detection of smaller, impalpable breast cancers has had no impact on treatment strategies.

Adult↗
PubMed1992

Effects of dantrolene on myoplasmic free [Ca2+] measured in vivo in patients susceptible to malignant hyperthermia.

Malignant hyperthermia (MH) is a genetic disease characterized by hypermetabolism in skeletal muscle following a triggering stimulus and can be reversed or pretreated with dantrolene sodium. The myoplasmic free [Ca2+] was measured, using Ca2+ selective microelectrodes in vivo in the superficial fibers of the sartorius muscle of eight MH-susceptible and eight control subjects. Both groups received continuous epidural anesthesia with chloroprocaine 3%. In both the control and MH muscle fibers, the myoplasmic free [Ca2+] was measured before and after the intravenous administration of a cumulative dantrolene dose of 0.5, 1.5, and 2.5 mg/kg. The mean resting myoplasmic free [Ca2+] was 0.112 +/- 0.004 microM (mean +/- SEM n = 32) in the control and 0.485 +/- 0.022 microM (n = 33) in the MH subjects. In the MH subjects, dantrolene induced a dose-dependent reduction in myoplasmic free [Ca2+]. The 0.5-mg/kg dose reduced it to 0.326 +/- 0.017 microM (n = 22), the 1.5-mg/kg dose to 0.233 +/- 0.015 microM (n = 25), and the 2.5-mg/kg dose to 0.092 +/- 0.008 microM (n = 26). In controls, dantrolene also reduced resting myoplasmic free [Ca2+] but to a lesser extent. The 0.5-mg/kg dose reduced it to 0.096 +/- 0.004 microM (n = 22), the 1.5-mg/kg dose to 0.077 +/- 0.003 microM (n = 23), and the 2.5-mg/kg dose to 0.068 +/- 0.002 microM (n = 27). The results of the study extend our previous findings in humans and swine and demonstrate that it is possible to measure myoplasmic free [Ca2+] in vivo in humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗
PubMed1991

Squamous cell carcinoma of the anal canal.

Between 1979 and 1988, 33 patients with squamous cell carcinoma of the anal canal were treated with chemoradiation. There were 24 women and 9 men, from 37 to 90 years of age (median: 63 years). Complete tumor regression occurred in 29 of the 33 patients (88%), only one of whom later developed recurrence. In the other four patients, there was persistent tumor after 3 months; three of these patients died within 2 years; and one is alive with distant metastases 2 years later. During the first 5 years of the study, seven patients with complete tumor regression underwent planned abdominoperineal resection following chemoradiation. Four of the abdominoperineal resection specimens were free of tumor, but three were not. These three patients, who had abdominoperineal resection within 3 months of chemoradiation, are disease-free. Ten of the 29 patients who had complete tumor regression had biopsies of the primary site 3 months after treatment. All biopsies were negative for residual carcinoma. At present, 26 patients (79%) are alive and disease-free from 2 to 10 years post-treatment (median: 4 years). Two patients died of unrelated causes, four of cancer, and one is alive with cancer. Complications of the chemoradiation required surgical intervention in two patients, and two others developed severe hematologic toxicity, for a complication rate of 12% (4 of 33 patients). There was no treatment-related mortality. These results support the efficacy of chemoradiation treatment for carcinoma of the anal canal. They suggest that abdominoperineal resection no longer need be part of the planned initial management, and that posttreatment biopsy of the primary site is unnecessary, unless palpable or visible abnormalities are present 3 months after treatment.

Adult↗
PubMed1990

Multimodal therapy in locally advanced breast carcinoma.

Among 879 patients treated for breast cancer between 1975 and 1984, advanced disease was found in 125 (14%). A subgroup of 34 (4%) presented with untreated locally advanced disease without demonstrable distant metastases at the time of diagnosis (stage IIIB = T4abed, NX-2,MO). During the first 5 years (1975 through 1979), 17 patients were treated primarily with sequential radiotherapy and chemotherapy (Group A). From 1980 to 1984 (Group B), the management consisted of four courses of induction multi-drug chemotherapy followed primarily by mastectomy and additional chemotherapy. The mean follow-up for the most recent group (Group B) is 48 months. Follow-up was complete. While the local disease control rate was the same for both groups (76%), the survival was remarkably different. Group A patients experienced a median survival of 15 months, and only one survived 5 years. In Group B, the median survival was 56 months with nine patients (53%) alive between 40 and 76 months, seven (41%) of whom are 5-year survivors. While the overall mortality of patients with inflammatory breast cancer was greater in both groups when compared with the group with noninflammatory disease, the survival of patients in Group B was better than in Group A for both inflammatory and noninflammatory cancers (p less than 0.01). Estrogen receptor, nodal, and menopausal status did not influence survival. These data suggest that neoadjuvant chemotherapy improves survival for patients with stage IIIB breast carcinoma and delays the establishment or progression of distant metastases. Mastectomy is an important component in the treatment of this disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Long-term results of surgical resection of locally advanced colorectal carcinoma.

This study was undertaken to review the long-term results of multivisceral resection of locally advanced colorectal carcinoma. Between 1964 and 1980, 1042 patients underwent exploratory surgery for colorectal cancer. Of these, 58 patients (5.5%) underwent curative multivisceral resection for suspected contiguous invasion by the primary tumor. Follow-up was complete for all patients. The primary tumors were located in the rectum (38 patients), sigmoid (9 patients), left colon (6 patients), and right colon (5 patients). En bloc resection of other viscera included uterus, adnexa, bladder, vagina, small intestine, abdominal wall, liver, stomach, kidney, and ureter. The operative morbidity and mortality rates were 31% and 1.7%, respectively. Resection margins were free of tumor in 54 patients. In the four patients with tumor-positive resection margins, recurrence of disease was evident between 8 and 22 weeks after surgery (mean survival time, 8.2 months). Carcinomatous invasion of the resected contiguous organ was confirmed in 49 patients (84%). The mean survival time for patients without lymph node metastases was 100.7 months, but it was only 16.2 months (p less than 0.01) for patients with lymph node metastases. Actuarial 5-year disease-free survival rate for patients without lymph node metastases was 76% (36 of 47 patients). None of the patients (0 of 11) with lymph node metastases survived for 5 years. Three of 36 of the 5-year survivors experienced recurrence of disease before the seventh postoperative year; no cancer-related deaths occurred between 7 and 25 years. These data suggest that survival in locally advanced colorectal carcinoma is more dependent on lymph node status than on the extent of local invasion. Effective disease control associated with survival in the long term can be achieved by multivisceral resection.

Adult↗
PubMed1989

Carcinoma of the anal region.

Preservation of anorectal function makes chemoradiotherapy attractive as the primary treatment in patients with squamous cell carcinoma of the anal region. Despite variations in techniques of chemoradiotherapy administration, the accumulated experience of a number of institutions indicates substantial improvement over previous approaches, which included surgery or radiation therapy individually. Although no longer providing the definitive therapeutic role in this disease, the surgeon is frequently asked to evaluate lesions suspected of being anal malignancies. In addition, it is the surgeon who most often performs the diagnostic biopsy, consults on local complications of chemoradiotherapy, and manages complications of local recurrence. In this context, optimal care includes early organization of the medical oncologist, radiation therapist, and surgeon to participate in the initial diagnostic evaluations, examinations with the patient under anesthesia, and follow-up during therapy. A complete response is often not evident until 2 to 3 months after treatment. We recommend a follow-up schedule of monthly visits for the first 6 months, examinations every 3 months for the next 2 years, and assessment every 6 months thereafter. Evaluation during early routine visits includes manual and proctoscopic examination of the perineum and rectum and review of the hemogram and liver enzyme levels in the serum. CT, MRI, or lower endoscopy procedures are performed only if clinical examination or studies suggest the possibility of recurrence or a second primary tumor. Patients with an incomplete response to therapy after 3 months often undergo examination under anesthesia with biopsy of suspect areas. Chronic inflammatory changes in the area of previous carcinoma may be interpreted as persistent disease. Thus histologic proof of recurrent malignancy must be obtained before considering surgical or chemoradiotherapy salvage treatment.

Anus Neoplasms↗
PubMed1989

Breast cancer detected by screening: the importance of long-term follow-up.

This study updates a 10- to 15-year follow-up of 136 patients with breast cancer among 10,187 symptom-free participants in a screening program. Mammography was the sole detection modality in 76 (56%) patients. The combination of mammography and physical examination revealed 41 (30%) cancers, whereas 19 (14%) were detected on physical examination alone. There were 26 (19%) noninvasive and 110 (81%) invasive neoplastic lesions. Positive axillary nodes were found in 34 (25%) patients, and 102 (75%) patients had negative nodes. For the entire group 5- and 10-year survival rates were 84.5% and 75%, respectively. After a minimum follow-up of 10 years and a median of 13.5 years, 102 patients are alive; one of these has a recurrence of cancer. Among the 34 patients who are no longer living, 14 died of causes unrelated to breast cancer. Two patients in the group in which diagnosis was based on mammography alone died of breast cancer, for a breast cancer-related fatality rate of 2.6% (2/76). By contrast, the breast cancer-related mortality of patients whose tumors were palpable at the time of detection was 30% (18/60) (p = 0.00001). This study suggests that long-term survival of patients whose breast cancer is detected by screening is, in large measure, dependent on the ability to detect malignant lesions before they become palpable.

Adult↗
PubMed1988

Transvaginal parametrial needle biopsy for detection of postirradiation recurrent cancer of the cervix.

During the 27-year period from 1956 to 1982, transvaginal parametrial needle biopsies were performed on 76 patients clinically suspected of harboring postirradiation recurrent cervical cancer without mucosal lesions suitable for biopsy under direct vision. Needle biopsies indicated cancer in 41 patients, resulting in 20 abdominal explorations. Eleven of these patients underwent total pelvic exenteration. Three patients survived longer than 5 years. Among 35 patients whose biopsies did not suggest cancer, eight proved to be false-negative as demonstrated by later progression of local and systemic disease. The remaining 27 patients in whom biopsies showed negative results were cured by radiation therapy. Bleeding, easily controlled by vaginal packing, occurred in one patient; in another, a pelvic abscess was drained 7 days after the biopsy. The authors conclude that when judiciously performed, transvaginal parametrial needle biopsy has a high diagnostic yield (89%) with minimal morbidity (2.6%). Its application during the careful observation of patients suspected to harbor recurrence may increase the operability rate and may offer selected patients a chance for cure by radical pelvic surgery.

Adult↗
PubMed1988

Primary carcinoma of the gallbladder: TNM staging and prognosis.

In order to investigate the lethality of carcinoma of the gallbladder and several of the coexisting features, a retrospective analysis of 53 patients with this disease was undertaken. Abdominal pain, obstructive jaundice, and a right upper quandrant mass were present in approximately one-half of the patients. Laboratory and radiological data were frequently nonspecific and did little to identify the diagnosis. The most common preoperative diagnoses were cholelithiasis or chronic cholecystitis. Cholecystectomy was the most frequently performed procedure. Fifteen wedge liver resections were performed. No radical or extended liver resections were done. Eighty-one percent of the patients had sufficient data for staging. Five patients (11.6%) had stage I lesions, three patients (7.0%) had stage II lesions, while 17 (39.5%) and 18 (41.9%) patients had stage III and IV lesions, respectively. Mean survival was 6.4 months for the entire group. Three patients are still alive (two longer than 5 years and one at 2 years) for an overall survival of 5.7%. Both staging and grading of the tumor correlated well with patient survival. Those patients with stage I lesions survived significantly longer (23 months vs. 3 months) than those with stage IV tumors. Also, those with more favorably graded (well-differentiated) neoplasms lived an average of 13 months longer than patients with poorly differentiated lesions.

Adenocarcinoma↗
PubMed1988

Total pelvic exenteration as a therapeutic option in advanced malignant disease of the pelvis.

Between 1966 and 1986, 99 patients underwent total pelvic exenteration at the Ellis Fischel State Cancer Center. Fifty-eight per cent of these were done for recurrence of carcinoma of the cervix uteri after radiation. The second most common type of malignant condition treated with total pelvic exenteration was localized advanced adenocarcinoma of the rectum. Fourteen of 99 patients died prior to discharge and after five years, 36 of 80 patients had survived. Seven deaths after discharge were attributed to the operation. There were 97 complications in 64 of the 99 patients after total pelvic exenteration prior to discharge. Between 1976 and 1981, one out of 14 patients undergoing total pelvic exenteration for locally advanced recurrent carcinoma of the cervix uteri died prior to discharge. Eight of 13 of the patients who survived that operation lived for five years. Total pelvic exenteration should be strongly considered in selected patients with locally advanced malignant lesions of the pelvis.

Adult↗
PubMed1987

Exenterative surgery for locally advanced rectosigmoid cancers. Is it worthwhile?

Among 1480 patients treated for cancers of the rectosigmoid over a 30-year period, 24 patients underwent total pelvic exenteration. These patients, 13 men and 11 women, had a median age of 64 years. Pathologic staging revealed 15 Dukes' B and nine Dukes' C lesions. For 17 patients, this operation was the only form of therapy. The operative mortality rate was 20.8%; however, the mortality rate has decreased to 13.3% during the past 20 years and to 9% in the past decade. Five complications occurred in the group surviving the procedure, resulting in a 26.3% morbidity rate. Three of the five complications occurred in patients who had previous radiation therapy or surgery. The overall 5-year survival rate was 41.6%. Those patients surviving the operation had 5- and 10-year survival rates of 52.6% and 31.5%, respectively. There were seven patients in whom the disease recurred at an average of 20.3 months after exenteration, and all died an average of 8 months later. The recurrence rate for patients with Dukes' B lesions was 27% compared with 57% for patients with Dukes' C lesions. The remaining 12 disease-free patients had a mean survival of 11 years. At present, four patients are alive and well 6 to 30 years after exenteration. The best predictor of morbidity was treatment before exenteration (p less than .005). Age older than 65 years and the presence of nodal metastases may contribute to increased mortality rates and recurrence, respectively, but these relationships were not statistically significant for the group. Total pelvic exenteration is advocated for selected primary, locally advanced, rectosigmoid lesions in good-risk patients; it can be achieved now with acceptable morbidity and mortality rates and a survival rate in excess of 40% at 5 years.

Aged↗
PubMed1986

The impact of breast cancer screening on survival. A 5- to 10-year follow-up study.

The Missouri Breast Cancer Detection Demonstration Project (BCDDP) at the Cancer Research Center in Columbia, Missouri, detected 136 malignant lesions among 10,187 asymptomatic participants between 1974 and 1980. Mammography was the sole detection modality in 76 or 56% of cases (Group 1). Mammography combined with physical examination revealed 41 (30%) additional cases (Group 2). Physical examination alone detected 19 (14%) cases (Group 3). Follow-up was complete in all cases. There were 26 (19%) noninvasive and 110 (81%) invasive lesions. Positive axillary nodes were found in 34 (25%) cases, and 102 (75%) patients had negative nodes. The overall 5-year survival was 84.5%. After a minimum follow-up of 5 years and a median follow-up of 8.5 years, 108 patients are alive, 5 of whom have recurrences. Among 28 deceased patients, 9 died of causes unrelated to breast cancer. The 5-year survival of Group 1 was 95% (72/76). Among this group of patients, 84% (64/76) had negative lymph nodes. At 5 to 10 years follow-up, there have been no breast cancer-related deaths among this group, and only one patient has recurrent disease 91 months after mastectomy. Furthermore, 85% (22/26) of all noninvasive lesions were found in this group. Of the remaining 12 patients diagnosed by mammography alone but who had positive nodes, the 5-year survival was 75% (9/12). By contrast, patients diagnosed by mammography plus physical examination (Group 2) experienced a survival of 71% (29/41) at 5 years. Sixty-three percent of patients diagnosed by physical examination had negative lymph nodes. Their 5-year survival was 84%, which contrasts with a 50% 5-year survival for patients with positive nodes. In Group 3, 79% (15/19) had negative nodes. The 5-year survival rate of this group was 74% (14/19), and the 5-year survival rate of the node-negative patients with invasive disease in this group was 29% and 21% lower than that of the node-negative patients with invasive disease of Groups 1 and 2, respectively (P less than 0.01). This study suggests that improved survival in breast cancer screening program is in large measure dependent on the ability to detect lesions before they become palpable. The authors conclude that mammography is a determining factor in early diagnosis, and at 5 to 10 years contributes significantly to improved 5- and 10-year survival rates.

Adult↗
PubMed1986

Haematogenous metastatic patterns in colonic carcinoma: an analysis of 1541 necropsies.

The sequence of events in haematogenous metastasis from colonic carcinoma was analysed, using 1541 necropsy reports from 16 centres. The findings are consistent with the cascade hypothesis that metastases develop in discrete steps, first in the liver, next in the lungs and finally, in other sites. Deviations of necropsy findings from the cascade model are largely explained on the basis of false negative reports. In only 216 of 1194 cases was there suggestive evidence that metastatic patterns (excluding lymph nodes) were causally related to lymphatic or non-haematogenous pathways. The incidence of metastatic involvement in 'other' (quaternary) sites correlated with target organ blood-flow (ml min-) per g, only when bone marrow and thyroid were excluded. In the thyroid the incidence was lower than expected on the basis of blood flow per g tissue; this may indicate that the thyroid is an unfavourable site for metastatic growth of colonic carcinoma. In the bone marrow it is higher; the latter may be due to delivery of cancer cells via both arterial blood and the vertebral venous plexus. Recognition of this pattern of metastases in the bone marrow could be important with respect of diagnosis and therapy, in patients with colonic carcinoma.

Aged↗