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Edward R Laws

Publications and source records attributed to Edward R Laws.

15 recordsLinked to original sources
PubMed2003

Key personalities in the development and popularization of the transsphenoidal approach to pituitary tumors: an historical overview.

Although the transsphenoidal procedure, as we know it today, was devised at the beginning of the last century, its acceptance and eventual widespread affirmation have been a slow but relentless process. Like many technologic and scientific advances, several individuals contributed to the perfection of an idea whose time had come. Yet, it is unequivocally accepted that a few key figures played a critical role in the development, preservation, and eventual widespread popularization of transsphenoidal surgery. These pioneers were original thinkers and bold (albeit careful) surgeons. Their persistence in the face of incredible obstacles provides a source of continuous inspiration.

Austria↗
PubMed2003

Gliadel for pituitary adenomas and craniopharyngiomas.

OBJECTIVE: We developed a protocol for a clinical trial of postresection implantation of Gliadel wafers in patients with aggressive, relentlessly recurring pituitary adenomas and craniopharyngiomas. METHODS: Ten patients, nine with pituitary adenomas and one with a craniopharyngioma, underwent implantation of from two to eight Gliadel wafers. RESULTS: No obvious adverse reactions occurred. Death as a result of disease progression occurred in two patients with malignant adenomas. One patient died as a result of a stroke after undergoing five surgical procedures and prior radiotherapy. The seven living patients have been followed for 5 to 27 months (mean follow-up, 19 mo). Four patients have been free of recurrent or residual tumor, two have stable residual disease, and one has experienced tumor progression. CONCLUSION: The results of this study suggest a role for Gliadel implantation in patients with recurring aggressive pituitary adenomas and craniopharyngiomas.

Adenoma↗
PubMed2003

Anemia, testosterone, and pituitary adenoma in men.

OBJECT: Older men with clinically nonfunctioning pituitary tumors have been noted to be anemic, to have hypopituitarism, and to have low serum levels of testosterone. The authors hypothesized that men with pituitary adenomas and hypogonadism have a physiologically related decrease in hematocrit. METHODS: A retrospective analysis was conducted of 216 patients older than 50 years of age who harbored pituitary adenomas. In 100 men serum testosterone levels and a complete blood (cell) count (CBC) were obtained before treatment; a CBC was also acquired in a series of women with pituitary adenomas. Using clinical laboratory standards, anemia was defined as a hematocrit less than 40% in men and less than 35% in women. Thirty-one (46.3%) of 67 men with low serum concentrations of testosterone were anemic. In men with low levels of testosterone, the average hematocrit was 39.9%, compared with 45.6% for men with normal testosterone levels (p < 0.001). Men with macroadenomas were most likely to have both anemia and a low serum concentration of testosterone. Anemia was associated with a low level of testosterone, adjusting for tumor size (odds ratio 19, 95% confidence interval 4.86-77.03). Of patients with anemia, 84% were men and 16% were women (p < 0.001). The prevalence of anemia in women was low and was not correlated with tumor size. Men receiving testosterone replacement therapy had a significantly higher hematocrit value than men with low or normal testosterone levels. CONCLUSIONS: These findings support a direct relationship between serum testosterone levels and hematopoiesis in men, and demonstrate that hematopoiesis is compromised in men who have low concentrations of testosterone due to a pituitary adenoma.

Adenoma↗
PubMed2003

Perioperative complications and neurological outcomes of first and second craniotomies among patients enrolled in the Glioma Outcome Project.

OBJECT: In many new clinical trials of patients with malignant gliomas surgical intervention is incorporated as an integral part of tumor-directed interstitial therapies such as gene therapy, biodegradable wafer placement, and immunotherapy. Assessment of toxicity is a major component of evaluating these novel therapeutic interventions, but this must be done in light of known complication rates of craniotomy for tumor resection. Factors predicting neurological outcome would also be helpful for patient selection for surgically based clinical trials. METHODS: The Glioma Outcome Project is a prospectively compiled database containing information on 788 patients with malignant gliomas that captured clinical practice patterns and patient outcomes. Patients in this series who underwent their first or second craniotomy were analyzed separately for presenting symptoms, tumor and patient characteristics, and perioperative complications. Preoperative and intraoperative factors possibly related to neurological outcome were evaluated. There were 408 patients who underwent first craniotomies (C1 group) and 91 patients who underwent second ones (C2 group). Both groups had similar patient and tumor characteristics except for their median age (55 years in the C1 group compared with 50 years in the C2 group; p = 0.006). Headache was more common at presentation in the C1 group, whereas papilledema and an altered level of consciousness were more common at presentation in patients undergoing second surgeries. Perioperative complications occurred in 24% of patients in the C1 group and 33% of patients in the C2 group (p = 0.1). Most patients were the same or better neurologically after surgery, but more patients in the C2 group (18%) displayed a worsened neurological status than those in the C1 group (8%; p = 0.007). The Karnofsky Performance Scale score and, in patients in the C2 group, tumor size were important neurological outcome predictors. Regional complications occurred at similar rates in both groups. Systemic infections occurred more frequently in the C2 group (4.4 compared with 0%; p < 0.0001) as did depression (20 compared with 11%; p = 0.02). The perioperative mortality rate was 1.5% for the C1 group and 2.2% for the C2 group (p = not significant). The median length of the hospital stay was 4 days in each group. CONCLUSIONS: Perioperative complications occur slightly more often following a second craniotomy for malignant glioma than after the first craniotomy. This should be considered when evaluating toxicities from intraoperative local therapies requiring craniotomy. Nevertheless, most patients are neurologically stable or improved after either their first or second craniotomy. This data set may serve as a benchmark for neurosurgeons and others in a discussion of operative risks in patients with malignant gliomas.

Central Nervous System Neoplasms↗
PubMed2003

Survival following surgery and prognostic factors for recently diagnosed malignant glioma: data from the Glioma Outcomes Project.

OBJECT: The Glioma Outcomes Project represents a contemporary analysis of the management of malignant (Grade III and Grade IV/GBM) gliomas in North America. This observational database was used to evaluate the influence of resection, as opposed to biopsy, on patient outcome as measured by the length of survival. Attempts were made to reduce the impact of selection bias by repeating the data analysis after omitting patients with major negative prognostic factors. METHODS: Outcome data from 788 patients accrued from multiple sites over a 4-year period (1997-2001) were analyzed with the primary outcome measure being length of survival. Of these, 565 patients with recent diagnoses formed the basis of the present analysis. Patients were systematically followed up until death or up to 24 months after enrollment in the study, and survival data were correlated with the histopathological grade and location of the tumor, the extent of surgery, the patient's performance status, and demographic factors. The median length of survival was 40.9 weeks for patients with recently diagnosed GBMs. The true median length of survival for patients with Grade III gliomas was not reached, although there was a 58% survival rate at 104 weeks. In multivariate analysis, resection rather than biopsy (p < 0.0001), age 60 years or younger (p < 0.0001), and a Karnofsky Performance Scale (KPS) score of 70 or greater (p = 0.0004) were associated with a prolonged survival time for patients with Grade III or IV gliomas. The prognostic value of resection compared with biopsy was maintained (p < 0.0001), even after eliminating patients considered to be "poor risk" (those with age > 60 years, KPS score < 70, or presence of multifocal tumors), who may have been overrepresented in the biopsy group. Survival "tails" at 24 months were 58% for Grade III gliomas and 11% for GBMs. CONCLUSIONS: These data provide Class II evidence to support tumor grade, patient's age, and patient's functional status as prognostic factors for survival in individuals with recently diagnosed malignant gliomas. Resection (compared with biopsy) is also a strong prognostic factor; however, no quantitative attempt was made to assess the true extent of the resection.

Adult↗
PubMed2003

Intrasellar schwannomas: report of two cases.

OBJECTIVE AND IMPORTANCE: The complex regional anatomic features surrounding the sella turcica make the differential diagnosis of intrasellar and parasellar lesions complicated. Sellar and parasellar schwannomas are rare. With the exclusion of parasellar schwannomas arising from cranial nerves within the cavernous sinus and extending into the sella, there have been only two reported cases of true intrasellar schwannomas. CLINICAL PRESENTATION: We describe the clinical, radiological, and pathological features of two cases in which the histopathological diagnosis of schwannoma was confirmed with immunohistochemical analyses and/or electron microscopy. INTERVENTION: The two cases were grossly resected via a transsphenoidal approach. Follow-up monitoring revealed no evidence of recurrence. CONCLUSION: Schwannomas may atypically occur in the sellar region, in which they demonstrate the typical light microscopic, immunohistochemical, and ultrastructural features observed in the peripheral nervous system. New and existing hypotheses regarding the histopathogenesis of intrasellar and parasellar schwannomas are presented.

Adult↗
PubMed2002

The neurosurgical management of Cushing's disease.

Cushing's disease and its associated clinical syndrome reflect the effects of excess cortisol on the individual. The cause of Cushing's disease is ordinarily an ACTH-secreting benign pituitary adenoma. The diagnosis of Cushing's disease is established by sophisticated endocrine testing and comprehensive imaging studies. Because of the devastating effects of excess cortisol, therapy that provides prompt and effective normalization of serum cortisol is essential. Currently, this goal is best achieved by transsphenoidal microsurgery. This paper reviews the clinical presentation, laboratory analysis, surgical management and outcome in patients with Cushing's disease.

Adenoma↗
PubMed2002

Hemangiopericytoma in the setting of acromegaly.

Acromegaly is associated with an increased incidence of neoplasia thought to be related in part to tonic increases in circulating levels of insulin-like growth factor-1 (IGF-1). Hemangiopericytomas, particularly those occurring in soft tissues, are known to possess IGF receptors. These tumors often behave aggressively and can be recalcitrant to surgery and radiation therapy. A 49-yr-old man presented with an erosive, midline scalp mass and cutis gyrata. Further diagnostic imaging and endocrinologic analysis confirmed two diagnoses: a hemangiopericytoma and acromegaly associated with an intrasellar pituitary tumor. Both the hemangiopericytoma and the pituitary adenoma were surgically resected; Western blot analysis confirmed the presence of IGF-1 receptors in the hemangiopericytoma. Two years later, the patient underwent resection of a right frontal hemangiopericytoma with an identical histologic phenotype and receptor positivity for IGF-1. The occurrence of a central nervous system hemangiopericytoma in patient with acromegaly is rare. Growth and recurrence of hemangiopericytoma may have been fostered by the presence of IGF-1 receptors. Paracrine mechanisms related to IGF-1 may have contributed to its pathogenesis and growth. The presence of IGF-1 receptors in hemangiopericytomas may have treatment implications for additional adjuvant therapies.

Acromegaly↗
PubMed2002

The long-term significance of microscopic dural invasion in 354 patients with pituitary adenomas treated with transsphenoidal surgery.

OBJECT: Pituitary adenomas are considered benign tumors; however, they may infiltrate surrounding tissues including the dura mater. In this paper the authors analyze the clinical significance of microscopically confirmed dural invasion by comparing a range of variables (age and sex of patients, adenoma type, adenoma size on magnetic resonance [MR] images, remission, residual pituitary disease, recurrence, survival, and disease-free interval after surgery) between patients with noninvasive adenomas and those with invasive ones. METHODS: Between 1992 and 1997 dural specimens were obtained in 354 patients with pituitary adenomas who underwent transsphenoidal surgery performed by the senior author (E.R.L.). Dural specimens were examined using routine histological methods and assessed for invasion by pituitary adenoma tissue. The dura was invaded by the pituitary adenoma in 161 patients (45.5%), and in 192 patients (54.5%) no evidence of dural invasion was found. Dural invasion was present significantly more frequently in the repeated surgery group (69%, 55 patients) than in the primary transsphenoidal surgery group (41%, 291 patients). The mean age of patients undergoing primary transsphenoidal surgery was significantly older in cases of invasive adenomas (50 years) compared with cases of noninvasive adenomas (43 years), and these age differences also correlated with adenoma size. Women tend to develop clinically evident, smaller adenomas at a younger age than men. Of the patients with pituitary adenomas that were 20 mm or smaller, 117 (76%) of 154 were women, whereas of the patients with adenomas that were larger than 20 mm, 74 (54%) of 137 were men. The frequency of dural invasion increased with increasing size of the pituitary adenoma as measured on MR images. In 291 patients who underwent primary pituitary surgery, the frequency of dural invasion according to adenoma size was 24% (< or = 10 mm), 35% (> 10 to < or = 20 mm), 55% (> 20 to < or = 40 mm), and 70% (> 40 mm). In patients who underwent primary transsphenoidal surgery, dural invasion was present in more than 50% of those with nonfunctioning adenomas and in 30 to 35% of patients with endocrinologically active adenomas. The mean diameter of the gonadotrophic adenomas and null-cell adenomas was significantly larger than that of each of the endocrinologically active adenomas. In 58 (20%) of 291 patients who underwent primary pituitary surgery there was residual pituitary disease postsurgery, and 20% of this subset of patients showed clinical improvement to such an extent that no further management was recommended. After pituitary surgery, residual tumor tissue was demonstrable significantly more frequently in patients with invasive adenomas than in those with noninvasive adenomas. Recurrences after initial remission (cure) of pituitary disease occurred in 18 (8.8%) of 205 patients between 2 and 79 months after primary pituitary surgery (median 25 months). The recurrence rate was not related to dural invasion in a consistent or significant fashion. Seven patients died between 14 and 79 months after pituitary surgery and all had invasive adenomas identified on gross observation at surgery and on microscopy. The survival rate was slightly but significantly decreased for patients with invasive adenomas (91%) compared with patients with noninvasive adenomas (100%) at 6 years postsurgery. CONCLUSIONS: The principal significance of dural invasion by pituitary adenoma is the persistence of tumor tissue after transsphenoidal surgery (incomplete adenomectomy; 20% in primary pituitary tumor resections). The increase in adenoma size with time and the concurrent development of dural invasion are the major factors that determine an incomplete adenomectomy. When the adenoma remains restricted to the sellar compartment or shows only moderate suprasellar extension, dural invasion may not yet have developed and conditions for complete selective adenomectomy are improved.

Adenoma↗
PubMed2002

Cushing's case XLV: Minnie G.

A 23-year-old patient who was examined in 1910 by Harvey Cushing triggered his lifelong interest in the syndrome that bears his name. "Minnie G.," as she became historically known, presented with a "...syndrome of painful obesity, hypertrichosis, and amenorrhea with overdevelopment of secondary sexual characteristics accompanying a low grade of hydrocephalus and increased cerebral tension." This case stimulated Harvey Cushing's inquisitive mind and sparked an interest that 20 years later culminated in his seminal report, "The basophil adenomas of the pituitary gland and their clinical manifestations (pituitary basophilism)." In this classic work, Cushing reported in detail the cases of two patients encountered from his own practice and 10 similar cases collected from the literature. Minnie G. was the first case that Cushing reported. The clinical course of that case is briefly reviewed in this article.

Adenoma↗
PubMed2002

Primary sellar lymphoma: radiologic and pathologic findings in two patients.

We describe the clinical, MR imaging, and pathologic findings in two cases of primary sellar lymphoma in immunocompetent individuals. Both patients had hypopituitarism, and one patient had a sixth cranial nerve palsy. MR images depicted sellar and suprasellar masses in both patients, and extension into the cavernous and sphenoid sinuses was also present in one patient. The pathologic diagnosis in both cases was large B cell lymphoma.

Aged↗
PubMed2002

Targeted delivery in primary and metastatic brain tumors: summary report of the seventh annual meeting of the Blood-Brain Barrier Disruption Consortium.

The November 2000 NIH report of the Brain Tumor Progress Review Group identified delivering and targeting therapeutic agents as a priority in the treatment of malignant brain tumors. For this reason, the seventh annual Blood-Brain Barrier Disruption Consortium meeting, partially funded by an NIH R13 Grant, focused on recent advances in targeted delivery to the central nervous system, clinical trials for primary and metastatic brain tumors using enhanced chemotherapy delivery, and strategies to lessen the toxicities associated with dose intensive treatments, using thiols.

Antineoplastic Agents↗
PubMed2002

Pituitary surgery: transsphenoidal approach.

THE TRANSSPHENOIDAL APPROACH for sellar tumors has evolved significantly since it was described initially during the first decade of the 20th century. The approach currently incorporates technological advancements and refinements in patient selection, operative technique, and postoperative care. Although many of these innovations are considered indispensable, the operative technique, as performed by contemporary neurosurgeons, is not standardized. This variability is a reflection of surgeon's preference, the lessons of experience, and the bias inherent in neurosurgical training. The methods and preferences described herein embody the distillation of an experience gained from 3900 transsphenoidal operations.

Cerebrospinal Fluid Otorrhea↗
PubMed2002

Use of FloSeal hemostatic sealant in transsphenoidal pituitary surgery: technical note.

OBJECTIVE: Bleeding during transsphenoidal pituitary surgery can lead to a variety of operative difficulties. When the endonasal transsphenoidal approach is used, even mild intraoperative hemorrhage can lessen visibility in the confined operative field of view. This technical note describes the use of a hemostatic agent we have found of benefit in obtaining prompt hemostasis during this operation. METHODS: Operative records were reviewed for an 18-month period for all patients who underwent transsphenoidal surgery since we began using FloSeal hemostatic sealant in January 2000. RESULTS: During the study period, 293 transsphenoidal operations were performed for pituitary lesions. Of these, 20 procedures involved vigorous or persistent bleeding. When the standard techniques for hemostasis failed or were inadequate, FloSeal, a sterile mixture of a gelatin matrix and thrombin component mixed at the time of use, was applied to the site of hemorrhage by use of a 14-gauge angiocatheter to reach the sella. We observed complete hemostasis immediately on application of FloSeal in all cases except one, which required a second application. Hemostasis was obtained immediately after the second application. No operations were aborted during this period as a consequence of undue bleeding. CONCLUSION: We detail the method in which we use FloSeal in transsphenoidal surgery and report our impression of its effectiveness. FloSeal has been demonstrated to be safe and biocompatible as compared with hemostatic agents currently in use.

Adolescent↗