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Michael O Meyers

Publications and source records attributed to Michael O Meyers.

9 recordsLinked to original sources
PubMed2006

Complications associated with neoadjuvant radiotherapy in the multidisciplinary treatment of retroperitoneal sarcomas.

INTRODUCTION: Retroperitoneal sarcomas (RPS) remain a therapeutic challenge due to high local recurrence rates. Preoperative RT offers theoretical advantages in the multidisciplinary care of RPS. The purpose of our study was to evaluate our experience using preoperative radiotherapy (PRT) in the treatment of RPS. METHODS: This is a single-institution review of patients with RPS treated with PRT from 1994 until 2004. Three radiation oncologists and four surgical oncologists were involved. Medical records, tumor registries, and death records were reviewed. RESULTS: Fourteen patients were included; nine were treated for primary presentation and five for recurrent disease. Histologic grade was grade I (n = 3), grade II (n = 3), and grade III (n = 8). Five patients received additional IORT. Radiotherapy complications were generally mild, including nausea (n = 3), diarrhea (n = 1), dehydration (n = 1), anemia (n = 1), and skin changes (n = 1); one required early cessation due to nausea. Thirteen patients had gross negative margins; while 7/13 had negative microscopic margins. Operative complications included anastomotic bleeding (n = 1), fluid collections (n = 2), ileus (n = 3), ascites (n = 2), temporary leg weakness (n = 1), and uncomplicated wound infections (n = 2). In patients with R0 or R1 resections, one and two year local control rates were 64 and 50%. Overall survival for all patients was 90% at 1 year and 74% at 2 years with median survival of 21 months. CONCLUSION: PRT and IORT can be administered effectively in carefully selected patients with resectable RPS. Larger multi-center studies are needed to delineate the role of PRT and IORT to improve local recurrence and survival rates in the treatment of RPS.

Aged↗
PubMed2006

Axillary lymph node count is lower after neoadjuvant chemotherapy.

BACKGROUND: Retrieval of fewer than 10 lymph nodes at axillary dissection (ALND) for breast cancer can represent anatomic variation or inadequate dissection. We postulated that despite aggressive ALND, a lower lymph node count is more frequent after neoadjuvant chemotherapy. METHODS: Patients who received neoadjuvant chemotherapy followed by ALND were compared with patients who received surgery first. All patients received a level I and II ALND at a single institution by one of the breast surgeons. The number of nodes retrieved at ALND was dichotomized into categories (< 10 and > or = 10), and compared using Fisher exact test. RESULTS: A total of 143 neoadjuvant and 170 surgery-first patients were studied. Patients treated with neoadjuvant chemotherapy were significantly more likely to have fewer than 10 lymph nodes retrieved at ALND than were the surgery-first patients (19/143 or 13% vs. 6/170 or 4%, P = .003). CONCLUSIONS: A low lymph node count is more common in patients after treatment with neoadjuvant chemotherapy and should not be assumed to represent an incomplete ALND.

Adult↗
PubMed2006

Experienced radio-guided surgery teams can successfully perform minimally invasive radio-guided parathyroidectomy without intraoperative parathyroid hormone assays.

Minimally invasive parathyroidectomy is an accepted treatment option for primary hyperparathyroidism. The need for intraoperative parathyroid hormone assays (iPTH) to confirm adenoma removal remains controversial. We studied minimally invasive radio-guided parathyroidectomy (MIRP) performed using preoperative sestamibi localization studies, intraoperative gamma detection probe, and the selective use of frozen section pathology without the use of iPTH. This is a single institution review of patients with primary hyperparathyroidism treated with MIRP by surgeons experienced in radio-guided surgery between October 1, 1998 and July 15, 2005. Information was obtained by reviewing computer medical records as well as contacting primary care physicians. Factors evaluated included laboratory values, pathology results, and evidence of recurrence. One hundred forty patients were included with a median preoperative calcium level of 11.3 mg/dL (range, 9.6-17) and a PTH level of 147 pg/mL (range, 19-5042). The median postoperative calcium level was 9.3 mg/dL. All patients were initially eucalcemic postoperatively except for one who had normal parathyroid levels. However, five (4%) patients required re-exploration for various reasons. Of the failures, one was secondary to the development of secondary hyperparathyroidism, and therefore would not have benefited from iPTH, one had thyroid tissue removed at the first operation, and three developed evidence of a second adenoma. One of these three patients had a drop in PTH level from 1558 pg/mL preoperatively to 64 pg/mL on postoperative Day 1, indicating that iPTH would not have prevented this failure. Thus, only three (2.1%) patients could have potentially benefited from the use of iPTH. MIRP was successful in 96 per cent of patients using a combination of preoperative sestamibi scans, intraoperative localization with a gamma probe, and the selective use of frozen pathology. This correlates with reported success rates of 95 per cent to 100 per cent using iPTH. We conclude that minimally invasive parathyroidectomy can be successfully performed without using iPTH assays.

Adenoma↗
PubMed2005

Staged sentinel lymph node biopsy before mastectomy facilitates surgical planning for breast cancer patients.

BACKGROUND: In patients with breast cancer who choose mastectomy with immediate reconstruction, the sentinel lymph node (SLN) status on permanent histology may complicate treatment if a metastasis is found. The purpose of this study was to determine how performing an SLN biopsy (SLNB) before the definitive operation would influence subsequent surgical procedures. METHODS: Our SLN database was searched for patients who underwent staged SLNB with subsequent mastectomy between 2001 and 2004. RESULTS: Twenty-five patients with 27 breast cancers underwent SLNB before mastectomy. Of them, 9 of 27 (33%) were node positive. All 9 patients underwent modified radical mastectomy. Three node-positive patients did not undergo immediate reconstruction. Of the remaining 6 node-positive patients, 5 underwent reconstruction with autologous tissue rather than a tissue expander. In contrast, 6 of 16 (37%) node-negative patients underwent reconstruction with a tissue expander. CONCLUSIONS: Staged SLNB assists in selecting the appropriate operation in patients who are considering immediate reconstruction.

Adult↗
PubMed2004

Is reporting of recurrence data important in pancreatic cancer?

BACKGROUND: Therapeutic approaches to patients with pancreatic cancer have undergone a paradigm shift in recent years. However, little is known about the outcome of patients with recurrent pancreatic cancer who undergo treatment. The purpose of this study was to identify patients with recurrent pancreatic cancer and to determine whether treatment after recurrence had any effect on outcome. METHODS: A review of all patients undergoing surgical resection with curative intent revealed 70 patients with documented recurrence and complete medical records. Patients were grouped into three categories: group 1 included those who received treatment after recurrence (n = 45), group 2 included those who were not offered treatment (n = 9), and group 3 included those with poor performance status who received no treatment (n = 16). RESULTS: The median overall survival for the three groups was 26, 18, and 14.5 months for groups 1, 2, and 3, respectively (P <.00001). The median survival after recurrence was 10 months, 6 months, and 1 month, respectively, for the three groups (P <.0001). CONCLUSIONS: This is the first series we are aware of that compares the outcomes of patients who received treatment after recurrence of pancreatic cancer with the outcomes of those who received no treatment. In this series, it seems that patients who were well enough to tolerate additional therapy had a longer survival than those who received supportive care only. This may be important in the analysis of adjuvant therapy trials of pancreatic cancer with survival as an end point.

Adenocarcinoma↗
PubMed2003

Angiogenesis and hepatic colorectal metastases.

Angiogenesis is a critical step in the metastatic cascade of colorectal cancer. Several angiogenesis inhibitors have been evaluated in animal models and have shown efficacy, but challenges remain in using these drugs effectively in the clinical setting. Although several of these angiogenesis inhibitors are currently being evaluated in clinical trials, alone or in combination with cytotoxic chemotherapy, early results suggest that angiogenesis inhibitors alone, when used for advanced disease, have minimal activity. It is likely that this class of drugs will prove more efficacious when used either in the setting of minimal disease as agents that may promote tumor dormancy or in combination with other conventional forms of therapy. In addition, strategies such as metronomic therapy have been proposed whereby lower doses of cytotoxic chemotherapy, given more frequently, may act via an antiangiogenic mechanism [67,68]. Another challenge is identifying methods of assessing response to antiangiogenic therapy. To date, traditional methods of identifying response to treatment have not proven effective. Several investigators are working toward identifying circulating endothelial or tumor-associated factors that may be useful in following treatment. Novel imaging techniques are also being evaluated with enhanced CT and MRI, and newer modalities. Hepatic colorectal metastases provide an opportune setting in which to accomplish these challenges because the high incidence of disease and the ability to measure tumor with a variety of techniques lend themselves to evaluation of antiangiogenic therapy.

Angiogenesis Inhibitors↗
PubMed2003

Locoregional strategies for colorectal hepatic metastases.

Hepatic colorectal metastases present a challenging problem in patients with recurrent colorectal cancer. Twenty percent of patients with recurrence will have liver metastases as a component of their disease, and only 10% of these patients will have isolated liver metastases that are resectable. Although systemic chemotherapy alone has not proven efficacious in the treatment of liver metastases, a number of options exist in managing these lesions. For those that are resectable, surgery remains the optimal treatment, with an expected 5-year survival rate of 33%-39% based on several large series. Hepatic artery chemotherapy is another adjunct treatment in patients undergoing resection and may further improve survival. This benefit may be even more pronounced when combined with systemic chemotherapy. Newer-generation agents are likely to further improve results. More recently, new therapeutic modalities have been used to treat unresectable lesions. These include hepatic artery chemotherapy and ablative techniques such as radiofrequency ablation and cryoablation. This article will highlight the data regarding hepatic resection for colorectal metastases, describe the rationale for and efficacy of hepatic arterial chemotherapy in the postoperative adjuvant setting and in unresectable liver disease, and review the current literature describing ablative techniques in the treatment of liver metastases.

Antineoplastic Agents↗
PubMed2002

Intraoperative detection of a bronchial carcinoid with a radiolabeled somatostatin analog.

Carcinoid tumors of the lung are rare neuroendocrine tumors that make up approximately 1 to 2% of all lung neoplasms. These tumors overexpress somatostatin receptors, and somatostatin analog therapy has become standard in the treatment of carcinoid tumors. In addition, radiolabeled somatostatin analogs have been used to diagnose and treat these lesions. We describe the case of a patient with a right lung mass diagnosed as a carcinoid tumor. The patient underwent complete resection of this tumor with the assistance of intraoperative detection with a handheld gamma probe after the administration of the radiolabeled somatostatin analog (111)In-pentetreotide. This approach allowed us not only to detect the tumor easily, but to scan the bed of the tumor after resection and to re-excise an area of increased radioisotope uptake that corresponded to the presence of residual tumor. We believe this to be the first reported case of bronchial carcinoid resected with the assistance of intraoperative gamma detection after the administration of a radiolabeled somatostatin analog. This technology allowed us to achieve a complete surgical resection with no residual tumor detected either pathologically or by somatostatin scanning.

Adult↗