Significance of wet autoclave pretreatment in immunohistochemistry

Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2 antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric study group as the standardized method for AgNOR analysis in archival material.     

Proliferative (mib1, mdm2) versus anti-proliferative (p53) markers in head and neck cancer. An Immunohistochemical study

Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT₂N₀M₀, R₀) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies (CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively. MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small and localized squamous cell carcinomas of the head and neck region.     

Videolaparoscopic treatment of liver hydatid cysts with partial cystectomy and omentoplasty

Hydatid disease is one of the world's most important health problems. Although several conservative approaches have been used for the management of this condition, surgery remains the ideal choice in most of the cases. Videolaparoscopic approach can safely be applied for the management of liver hydatid cysts if several precautions are undertaken. In this study, we present two liver hydatid cyst cases successfully treated with partial cystectomy and omentoplasty using videolaparoscopic approach.     

Prevalence of known and hidden alcoholism in the revisited lundby population

Summary Using the new data from a second followup of the Lundby 1947 cohort, the aim of the present paper has been to analyze some relationships between known and hidden alcoholism in a Swedish general population sample. Information was collected by psychiatrists trough free, exploratory field interviews checked against documentary records. Alcoholism was medically defined for present purposes. Information was obtained for 98% of the 952 men surviving the cross-section date July 1, 1972. The distribution of alcoholism and other psychiatric disorders in the total population and in age subgroups was analyzed epidemiologically. The true prevalence of alcoholism in the adult men was 9.5%, comprising 7.2% known and 2.3% hidden. The proportion of hidden to known cases was 0.301 (Temperance Boards 0.871, Psychiatric Agencies 0.961, Drinking and driving offences 4.31). The main finding that about 70% of male alcoholics in Lundby appears to be known to the agencies is at variance with current views that there is an iceberg under the tip, though consistent with Rubington's suggestion that so-called hidden alcoholism is not totally but partially invisible in welfare societies.     

99mTc-gentamicin: Chemical and biological evaluation

^99mTc-Gentamicin complex, a new agent for renal studies, is prepared by the reduction of pertechnetate by stannous chloride. Organ distribution in rats and paper chromatography with Whatman 3MM paper [developed in n-butanol, acetic acid, and water (4:1:1)] were favored as analytical tools for determination of labeling parameters of ^99mTc-Gentamicin. A higher concentration of stannous ion is responsible for the formation of insoluble technetium species which concentrate in the liver. The mean kidney: liver ratio of 10.4:1 was obtained 1 h after injection. This confirms that scintigraphic delineation of kidneys is highly satisfactory.     

Pancreatic tumors in multiple endocrine neoplasia type 1: Clinical presentation and surgical treatment

Among 33 patients with endocrine pancreatic tumors due to multiple endocrine neoplasia type 1 (MEN-1), 19 (58%) patients had hypergastrinemia, 7 (21%) patients had hyperinsulinism, and 7 (21%) patients had clinically non-functioning lesions. At least one gross tumor was found in all patients undergoing pancreatic surgery, including those with negative localization studies prior to operation. The patients also had additional macroscopic tumors as well as numerous microadenomas, and the lesions frequently were positive for immunostaining with multiple hormones, mainly pancreatic polypeptide, insulin, glucagon, and somatostatin. Duodenal endocrine lesions were found in 4 of 5 investigated patients and stained with gastrin and somatostatin antibodies. Distal, mainly subtotal pancreatic resection, was performed in 18 patients, eventually combined with caput tumor enucleation or duodenotomy, while a few patients underwent only tumor enucleation or a Whipple procedure. The long-erm outcome of operation was most favorable in patients with hyperinsulinism; only 1 patient had clinical recurrence. Patients with hypergastrinemia experienced only transitory lowering of serum gastrin values after pancreatic surgery and 47% of them had or developed metastases. Such tumor spread was seen in 57% of the patients with non-functioning lesions. Nine patients died from progressive tumor disease during follow-up. Consistent with previous studies, we found that surgery is indicated in MEN-1 patients with hyperinsulinism even if a lesion is not visualized by radiology. In addition, these indications should be extended to also include patients with only biochemical markers of disease, including elevations of gastrin, as these indicate the presence of gross tumors. This strategy should be applied especially in patients with aggressive family histories to possibly reduce the risk of malignant tumor progression.

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Resumen Entre 33 individuos con tumores pancréaticos endocrinos como componente del síndrome de neoplasia endocrina múltiple tipo 1 (NEM-1), 19 pacientes (58%) tenían hipergastrinemia, 7 (21%) hiperinsulinismo y 7 (21%) lesiones clínicas no funcionantes. En la totalidad de los pacientes sometidos a cirugía pancreática fue hallado por lo menos un tumor, incluso en aquellos con examenes de localización negativos anteriores a la operación. Estos pacientes también albergaban tumores macroscópicos, así como numerosos microadenomas; con frecuencia las lesiones demostraron inmunocoloración con diferentes hormonas, principalmente polipéptido, insulina, glucagón y somatostatina. Se encontraron lesiones endocrinas duodenales en 4 de cada 5 pacientes investigados, las cuales colorearon con gastrina y anticuerpos a la somatostatina. Se practicó resección pancreática distal (principalmente resección subtotal) en 18 pacientes, eventualmente combinada con enucleación del tumor (cuando éste se hallaba ubicado en la cabeza del páncreas) o duodenectomía; solamente unos pocos pacientes fueron sometidos a simple enucleación del tumor o al procedimiento de Whipple. El resultado a largo plazo fue más favorable en los pacientes con hiperinsulinismo, puesto que sólo uno presentó recurrencia clínica. Los pacientes con hipergastrinemia exhibieron apenas una disminución transitoria de los valores de gastrina sérica luego de la cirugía pancreática. Cuarenta y siete por ciento del conjunto tuvo o desarrolló metástasis, en tanto que la extensión local del tumor se presentó en 57% de los casos con lesiones no funcionantes. Nueve pacientes murieron por progresión de la neoplasia en el curso del seguimiento. En acuerdo con sugerencias previas, se considero quo la cirugía está indicada en pacientes con NEM-1 e hiperinsulinismo, aún en los casos en que no se visualiza radiológicamente la lesión, pero que la indicación puede ser ampliada para incluir también pacientes con sólo marcadores bioquímicos, tales como niveles elevados de gastrina, indicativos de la presencia de tumores macroscópicos. Esta estrategia debe ser aplicada principalmente en aquellos pacientes con historia familiar agresiva, con lo cual tal vez se reduce el riesgo de progesión maligna del tumor.

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Résumé Parmi 33 patients ayant une tumeur pancréatique endocrine due à une néoplasie endocrine multiple de type 1 (MEN-1), 19 (58%) avaient une hypergastrinémie, 7 (21%) un hyperinsulinisme et 7 (21%) une lésion cliniquement muette. On a mis en évidence au minimum une grosse tumeur chez tous les patients, y compris chez ceux dont les examens préopératoires de dépistage tumoral étaient négatifs. Les patients étaient également porteurs de tumeurs macroscopiques et de nombreux microadénomes. Les lésions montraient souvent un immunomarquage positif pour de multiples hormones, principalement le polypeptide pancréatique, l'insuline, le glucagon et la somatostatine. Des lésions endocrines duodénales furent retrouvées chez 4 des 5 patients explorés; elles montraient un immunomarquage avec les anticorps angigastrine et anti-somatostatine. Une résection pancréatique distale, le plus souvent subtotale, a été réalisée chez 18 patients. Elle était éventuellement complétée par une énucléation tmorale de la tête ou par une duodénotomie. Peu de patients ont bénéficié d'une simple énucléation ou d'une intervention de Whipple. L'évolution postopératoire à long terme a été plus favorable en cas d'insulinome puisque seul un patient a eu une récidive clinique. Les patients atteints de gastrinome n'ont présenté que transitoirement une diminution des taux sériques de gastrine après la chirurgie pancréatique. Quarante sept pour cent de ces patients avaient ou ont développé des métastases contre 57% des patients porteurs de lésions sans traduction clinique. Neuf patients sont décédés en raison de l'extension tumorale au cours du suivi. Conformément à des suggestions antérieures, la chirurgie semble indiquée chez les patients atteints de MEN-1 avec hyperinsulinisme même si la radiologie ne visualise pas de lésion. Mais cette indication peut être élargie aux patients dont seuls les paramètres biologiques sont en faveur d'une grosse tumeur (dont l'hypergastrinémie). Cette stratégie pourrait convenir particulièrement aux patients ayant des antécédents familiaux importants; elle permettrait peut-être de réduire le risque d'extension tumorale.

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Presented at the International Association of Endocrine Surgeons in Stockholm, Sweden, August, 1991.     

Method for Dissection of Mesenteric Metastases in Mid-gut Carcinoid Tumors

With adequate medical management the midgut carcinoid tumor generally is an indolent malignancy associated with substantial life expectancy and appreciable life quality, even in the presence of liver metastases and significant tumor burden. Abdominal complications may occur in this entity of carcinoids owing to entrapment of intestines and encasement of mesenteric vessels by mesenteric metastases and associated marked mesenteric fibrosis. This may be the cause of abdominal pain, disabling diarrhea, weight loss to the extent of malnutrition, and eventually the risk of death with acute or chronic intestinal obstruction or intestinal gangrene. Operative removal of the mesentericointestinal lesion is often indicated to prevent or treat these complications but may be technically difficult when mesenteric metastases extend in the vicinity of major vessels in the mesenteric root. At laparotomy 56 patients with advanced midgut carcinoids underwent removal of the mesenteric tumor with a method for preserving the mesenteric vessels. This was feasible by mobilizing and releasing the right colon and mesenteric root from posterior adhesions, identifying the mesenteric artery below the pancreas, and free-dissecting this artery on the tumor capsule in the mobilized mesentery. Dissection was successful even with tumors initially judged inoperable unless tumor growth completely surrounded the mesenteric vessels or extended retroperitoneally. One patient was subjected to distal intestinal artery bypass. Symptom relief was been substantial and often of long duration after mesenteric tumor removal in patients who prior to surgery often had threatening intestinal ischemia. Patients with advanced midgut carcinoids may benefit markedly from dissectional removal of mesenteric tumors, which (conceivably better than conventional wedge resection) preserves the length of the remaining intestine.