Frequency Of Malignant Tumors Research Articles

Endoscopic Ultrasonography-Guided Fine-Needle Aspiration for Duodenal Subepithelial Lesions Showing a Hypoechoic Mass on Endoscopic Ultrasound Imaging.

For duodenal subepithelial lesions showing a hypoechoic mass on endoscopic ultrasound imaging, the utility of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types have not been the focus of previous literature. This study aimed to clarify this. This prospective observational study enrolled 22 consecutive patients who underwent endoscopic ultrasoundguided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass on endoscopic ultrasound. Immunohistochemical analysis was performed for all endoscopic ultrasound-guided fine-needle aspiration and surgically resected specimens. The main outcome measures were the technical results of endoscopic ultrasound-guided fine-needle aspiration and the frequency of histological types of duodenal subepithelial lesions with hypoechoic mass. Thirteen fine-needle aspiration specimens were obtained from the duodenal bulb and eight from the descending duodenal region. The puncture was not performed because of intervening vessels in one patient. The diagnostic rate was 81% (95% confidence interval: 58.1-94.6, 17/21 patients). In 12 patients receiving surgical resection (excluding one cancellation of endoscopic ultrasoundguided fine-needle aspiration), the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration was 75% (95% confidence interval: 42.8-94.5, 9/12 patients). No complications were observed. The histopathological diagnoses included 11 cases of gastrointestinal stromal tumor (50%), 2 cases of leiomyoma (9%), 2 cases of metastatic cancer (9%), 2 cases of benign inconclusive, and 1 case each of carcinoid, malignant lymphoma, leiomyosarcoma, gauzeoma, and aberrant pancreas (4.5% each). The frequency of malignant tumors in the duodenal subepithelial lesions with hypoechoic mass group was 73% (16/22 patients). Endoscopic ultrasound-guided fine-needle aspiration for duodenal subepithelial lesions with hypoechoic mass was safe and accurate. As duodenal subepithelial lesion with hypoechoic mass has a reasonably high possibility of containing malignant tumors, it is desirable to perform endoscopic ultrasound-guided fine-needle aspiration.

Previous, simultaneous, or subsequent occurrence of malignant tumours in patients with primary hyperparathyroidism: a closer look at the single-tertiary-centre cases.

Our aims were to explore the relationship between primary hyperparathyroidism (pHPT) and malignant tumour development, to determine the frequency and the time of occurrence of malignant tumours in patients with pHPT, and to evaluate the characteristics of pHPT in these patients. This retrospective cohort study included consecutive individuals who were diagnosed with pHPT aged 18 years or older in a university hospital during a 7-year period. A total of 198 patients with pHPT were reviewed retrospectively. Demographic, clinical, biochemical, radiologic findings, and histopathological diagnosis were collected from the electronic medical records of the hospital system. The mean age of the study population was 58 ± 13 years and was predominantly female (female/male: 162/36). There were 42 (21.2%) patients with malignant tumours. Five (12%) out of 42 patients had metachronous double malignancies. The most common 2 concurrent malignancies were breast (36.1%) and thyroid (17.0%). Sixty-eight per cent of the malignant tumours occurred before the diagnosis of pHPT. A higher percentage (87.5%) of simultaneous tumours was seen in the thyroid gland. No statistically significant differences were observed between patients with and without malignant tumours in terms of demographic, clinical, biochemical, radiological, and histopathological features. The median follow-up duration was 24 months after parathyroid surgery. The results of this study revealed that pHPT was associated with various tumour types. The frequency of malignant tumours was 21.2%. Breast and thyroid cancers were the most common 2 cancers coexisting with pHPT. A large percentage of malignant tumours occurred before the diagnosis of pHPT. A higher percentage of simultaneous tumours was seen in the thyroid gland. pHPT patients with and without malignant tumours seemed to have similar characteristics.

Clinically latent and autopsy-verified inflammatory disorders and malignant tumours in transplant patients

AimsThe number of clinical autopsies decreases while the rate of missed relevant diagnoses is known to be 2%–20%. In this study, we focused on postmortem examinations of patients after transplantation...

Strain difference in transgene-induced tumorigenesis and suppressive effect of ionizing radiation.

Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/−, p53−/−) and Hd-rR HNI hybrid (p53+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/− fish than in p53−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.

CT features of thyroid nodules with isolated macrocalcifications detected by ultrasonography.

PurposeA thyroid nodule with an isolated macrocalcification is visualized as a calcified nodule with complete posterior shadowing on ultrasonography (US). This study aimed to determine the computed tomography (CT) features of isolated macrocalcifications detected using US.MethodsThis study included 20 patients who had thyroid nodules with isolated macroalcifications and underwent neck CT or chest CT. The patients were enrolled from a sample of 82 patients with isolated macrocalcifications detected by US drawn from 7,142 consecutive patients who underwent thyroid biopsy at two institutions. We evaluated the CT features of nodules with isolated macrocalcifications and categorized them as central or rim calcifications. We assessed the nodule size and the frequency of nondiagnostic fine-needle aspiration (FNA) results and malignant tumors according to the CT features of isolated macrocalcifications.ResultsCT scans showed central calcifications in 18 (90.0%) and rim calcifications in two (10.0%) of the 20 nodules with isolated macrocalcifications. Among the 18 nodules with central isolated macrocalcifications, complete compact calcification was found in six nodules and partial coarse calcification in 12 nodules. In 18 nodules with central isolated macrocalcifications, the nondiagnostic FNA rate and frequency of malignant tumors were not significantly different between complete and partial central calcifications (P=0.620 and P=0.999, respectively). Malignant tumors were only found in nodules with central isolated macrocalcifications.ConclusionThe majority of nodules with isolated macrocalcifications showed central calcifications on CT. Thyroid nodules with isolated macrocalcifications detected by US should not be classified as having a type of rim or peripheral calcification.

External validation of the Japanese difficulty scoring system for minimally-invasive distal pancreatectomies

IntroductionPreoperative prediction of the difficulty of surgery would be useful for surgeons embarking on MIDP. A novel difficulty scoring system(DSS) was recently developed in Japan but has not been externally validated. This study aims to externally validate the DSS determine its association with important clinical outcome parameters. MethodsRetrospective review of 90 patients who underwent MIDP from 2006 to 2018. The patients were stratified into 3 groups (low, intermediate and high difficulty) according to the DSS with some minor modifications. ResultsDifficulty of MIDP was classified as low in 45(50%), intermediate in 32(35.5%) and high in 13(14.4%). Comparison between the baseline characteristics across the 3 difficulty groups demonstrated a significant difference in the frequency of malignant tumors, larger tumor size, frequency of extended pancreatectomies and use of robotic assistance. There was statistically significant increase in operation time, blood loss and blood transfusion rate across the 3 groups from low to high difficulty. ConclusionThe DSS correlated significantly with operation time, blood loss and blood transfusion rate. These findings support the validity of the system.

External validation of the Japanese difficulty scoring system for minimally-invasive distal pancreatectomies

Introduction: Preoperative prediction of the difficulty of surgery would be useful for surgeons embarking on minimally-invasive distal pancreatectomy(MIDP). A novel difficulty scoring system(DSS) was recently developed in Japan but has not been externally validated. This study aims to externally validate the DSS determine its association with important clinical outcome parameters Method: Retrospective review of 90 patients who underwent MIDP from 2006 to 2018. The patients were stratified into 3 groups (low, intermediate and high difficulty) according to the DSS with some minor modifications. Result: Difficulty of MIDP was classified as low in 45(50%), intermediate in 32(35.5%) and high in 13(14.4%). Comparison between the baseline characteristics across the 3 difficulty groups demonstrated a significant difference in the frequency of malignant tumors, larger tumor size, frequency of extended pancreatectomies and use of robotic assistance. There was statistically significant increase in operation time, blood loss and blood transfusion rate across the 3 groups from low to high difficulty. Conclusion: The DSS correlated significantly with operation time, blood loss and blood transfusion rate. These findings support the validity of the system.

Squamous Cell Carcinoma Developed in Chronic Osteomyelitis

Abstract Introduction. Squamous cell carcinoma is the second as frequency in malignant tumors of the skin, representing 20% of this type of cancer. Inferior lip squamous carcinoma is most frequent, of 94%, because the trauma, sunburns, smoke and radiations are more frequent. Metastasis at distance in the area with chronic osteomyelitis is a rare situation. Material and method. A 78-year-old male, treated for inferior lip carcinoma, without any oncological treatment, was admitted in our clinic for a leg tumor on the anterior part, developed over a scar after osteomyelitis treated in the adolescence. The tumor growth was quick. We decided the treatment plan from the point of view of a multidisciplinary approach, plastic surgeon-orthopedistoncologist- dermatologist. A biopsy from the extraosseous tumor was performed and after the histological confirmation, the resection of the tumor block was made. For the confirmation of the bone invasion, we had to repeat the immunohistochemistry twice because the first result was negative. Until the final decision, the patient had an external fixation on the leg. A large tissue appeared on the area of resection, the aspect being suggestive for granulation. Amputation was decided after the complementary investigations and another biopsy from the granulation tissue. Results and conclusions. Squamous cell carcinoma of the lip needs prophylactic laterocervical ganglia resection for limiting metastasis.

Benign features of infection-related tumor-like lesions of the lung: A retrospective imaging review study.

Differentiation of benign and malignant pulmonary tumor-like lesions is challenging but increasingly important. We evaluate the most common imaging features in benign lesions based on the frequency of their appearance and compare with corresponding frequencies in malignant tumors from literature. Retrospective imaging review study in one center between 1 January 2012 and 30 June 2014. We reviewed the data from 2466 pathological examinations of lung specimens collected from the hospital. We excluded malignant or non-tumor-like lesions and identified 133 infection-related lesions for imaging review. The frequency of 11 benign imaging features was evaluated in the selected infection-related tumor-like pulmonary lesions and was compared with corresponding frequency in malignant tumors. Most of the evaluated lesions were seen to have one to four benign features. The two most common benign features are marginal ground glass or infiltrates (62.4%), followed by pleura-based wedge shape (50.4%). Features with significantly higher frequency in benign infection-related lung lesions than malignancy are calcification or hyperdensity, pleura-based wedge shape, adjacent clustered small nodules, and strongly or poorly enhanced soft tissue part. Infection-related lung lesions usually have one to four benign features and the common features with significantly higher frequency than malignant condition are pleura-based wedge shape, calcification or hyperdensity, adjacent clustered small nodules, and strongly or poorly enhanced soft tissue part.

P009: Epidemiology, microbiology and outcome of community-οnset gram-negative bacteremias in a Greek University Hospital

Among 145 patients with gram-negative COB, 83 (57.2%) had HCAB and 62 (42.8%) had CAB. The frequency of malignant tumors, renal insufficiency and dementia was higher in patients with HCAB than with CAB. In both groups Escherichia coli was the mostcommon causative agent but the prevalence of Klebsiella pneumoniae in HCAB was significantly higher than CAB (19.3% vs. 4.8%). Patients with HCAB had higher Charlson score and higher Pitt bacteremia score, less frequent administration of appropriate empirical antibiotic treatment and higher probability of death than patients with CAB. The antimicrobial resistance in HCAB aι CAB patients respectively, was found 27/83 (32.5%) vs. 4/62 (6.5%) (P<.001) to third-generation cephalosporins (3GC), 22/83 (26.5%) vs. 7/62 (11.3%) (P=.021) to aminoglycosides, 29/83 (34.9%) vs. 9/62 (14.5%) (P=.005) to quinolones. Bacteria that produced ESBL were 16/76 (21.1%) vs. 2/59 (3.4%) (P=.003), and carbapenem-resistant were 10/83 (12.0%) vs. 2/62 (3.2%) (P=.056) in HCAB aι CAB patients respectively Conclusion There are significant differences in the severity of underly- ing diseases, causative pathogens, antibiotic resistance, outcome and treatment between the two groups. In our region 3GC, aminoglycosides or fluoroquinolones are pro- posed as appropriate empirical treatment for patients with CAB, whereas in patients with HCAB carbapenems should be the initial therapy. Disclosure of interest None declared.

Urinary tract nosocomial infections at the Clinical centre in Kragujevac

Urinary tract infections are the most frequent hospital infections and account for about 40% of total hospital infections. The main risk factor for their development is the use of catheters. Assessment of basic epidemiological and etiological characteristics of nosocomial urinary tract infections (NUTIs) and investigation of differences in risk factors among the patients with NUTIs with and without the urinary catheter. The study comprised patients treated in chosen units/ of the Clinical Center in Kragujevac, in whom NUTI was registered during 2009. Differences in risk factors for NUTIs between the catheterized and uncatheterized patients were tested by the logistic regression analysis. NUTIs was registered in 162 patients whose average age was 66.2 +/- 13.5 years with approximately equal gender participation (51.2% men and 48.8% women). Almost three quarters of the patients with NUITs had indwelling urinary catheter, 12.0 +/- 7.7 days on average (from 1 to 39 days). In the patients with urinary catheter, the risk for NUITs was significantly positively associated with emergency admission to hospital treatment (p=0.0185). The uncatheterized patients had a significant frequency of malignant tumours comparing to the patients with a urinary catheter (p=0.039). The compared groups did not differ in other risk factors. The most frequently isolated microbial agents was Klebsiella spp (37.3%), then Pseudomonas aeruginosa (14.1%) and Proteus mirabilis (11.9%). Most of the bacteria showed a great level of resistance to frequently used antibacterial drugs, even up to 100%. It is necessary to define national recommendations for the prevention and control of NUTIs in the future.

Skeletal metastatic carcinoma: A case from 15th–20th century Coimbra, Portugal

AbstractThis paper discusses the differential diagnosis of unusual and distinct pathological changes in the skeletal remains of a 40+‐year‐old female from 15th–20th century Coimbra (Portugal). The most affected area seems to have been the skull, but multiple lesions, lytic and/or blastic, have been found throughout the post‐cranial skeleton, more specifically in the scapulae, clavicles, humerus, sternum, ribs, sacrum, innominates and femurs. The differential diagnosis of the lesions gave rise to several possible pathological conditions, namely, Langerhans cell histiocytosis (granulomatosis or Histiocytosis X), multiple myeloma and metastatic carcinoma. Various macroscopic and radiological aspects lead us to consider metastatic carcinoma as the most probable diagnosis. Despite the argumentative identity of the possible primary lesion, age, sex and the mixed nature of the osseous response are consistent with cancer of the breast but do not exclude other carcinomas, namely lung cancer. With temporal and regional differences emerging in the frequency of malignant tumours, the identification of new cases becomes important, particularly from geographic areas where few cases have been reported. In fact, the present report adds to the only case of metastatic carcinoma detected in non‐identified Portuguese human skeletal remains until now. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Evaluation of occurence of cancer of the lung among young people in six regions of the western Ukraine

21188 Background: Analysis of the cases of malignant lung tumors of young people (&lt;34 yrs, born in 1963–2004) and diagnosed in 1997–2004 was made using the materials of the database of cancer registers of Volyn (V), Ivano-Frankivsk (IF), Lviv (L), Rivne (R), Ternopil (T) and Chernivtsi (C) regions. The population of young people &lt;34 yrs of this region - 4.2 million/year. Results: Among 7541 cases of cancer in the six regions of the Western Ukraine malignant tumors of the lungs were diagnosed in 102 cases (1.4%). This pathology was registered in males in 57 cases, and in females in 45. The number of males with tumors of the lungs prevailed in V, IF, L, T. The number of young males and females with such pathology during the said period was the same - 11 cases in each gender group - in R. The youngest among the 102 individuals from the above said six regions were a boy aged 6 and a girl aged 16 from R. Combination with other tumors was observed in three females (C49, C53, C58) and one male (C81). In C among 766 cases of malignant tumors in young people &lt;34 years lung cancer were detected in 5 (0.7%). Among 959 cases of cancer such tumors of the lungs were detected in 8 (0.8%) in V. Among the young people &lt;34 years this pathology was detected in 14 (1.2%) in IF out of all 1156 cases of malignant tumors, in T - 947 tumor - 15 cases (1.6%). Among the six above regions in L there have been detected 2465 cases of malignant tumors, of which lung cancer were diagnosed in 38 - 1.5%. The highest frequency of occurrence of this pathology was registered in R (1.8%) - 22 cases in 1248 cases of malignant tumors. Conclusions: Fluctuation of frequency of this pathology in all these regions in various years during the investigated period had a wave-like character. As each of these regions is characterized by different geographic and climatic conditions, physical and chemical factors, exhausts of industrial enterprises, the study of frequency of malignant tumors in young people will permit to evaluated more objectively contribution of hereditary factor in the development of this pathology. The perspectives of further research in this field lie in the study of the role of genetic predisposition to the occurrence and development of malignant tumors in each patient, taking into account ecological zone of residence, occupational hazards and harmful habits. No significant financial relationships to disclose.

Malignant tumors in two ancient populations: An approach to historical tumor epidemiology

The actual increase in the rate of malignant tumors has been ascribed to a higher life expectancy and the influence of various environmental factors. Herein, we present data on the frequency of malignant tumors in paleopathologically well-defined historic populations. Thereby, we looked for malignant growth affecting the skeleton in three study populations of 905 individuals that have been excavated from the necropoles of Thebes-West and Abydos, Upper Egypt covering the time period between 3200 and 500 BC and 2547 individuals that have been buried in a Southern German ossuary dating from between AD 1400 and 1800. The tissue preservation of both the Egyptian and Southern German material was excellent. All available specimens were subjected to a very careful macroscopic examination; isolated findings were also radiologically investigated. In parallel, anthropological data, such as gender and age at death, were recorded. We identified 5 cases of malignant tumors affecting the skeleton in the Egyptian material and 13 cases affecting the skeletal material from Southern Germany. In most instances, multiple osteolytic lesions with slight osteoblastic reaction are strongly suggestive for metastatic carcinoma. Few cases with poorly reactive osteolyses were most compatible with plasmacytoma. Relative tumor frequencies on an age- and sex-adjusted population basis (using a mathematic model of skeletal involvement of malignant tumors in a well-defined English study population from AD 1901 to 1905) indicated that the tumor rates were not statistically different between ancient Egyptian, the historical Southern German and the recent English reference population. These observations indicate that malignant tumors were present in spatially and temporarily different populations over the last 4000 years with an age- and gender-adjusted frequency not different from Western industrial populations of c. 100 years ago. Therefore, we conclude that the current rise in tumor frequencies in present populations is much more related to the higher life expectancy than primary environmental or genetic factors.

Pattern of malignant diseases at the University of Benin Teaching Hospital

This study was designed to evaluate the pattern of malignant diseases seen at the University of Benin Teaching Hospital over a 20-year period (January 1980-December 1999). A total of 2258 histologically confirmed malignant diseases were seen with the predominant tumours comprising carcinoma of the cervix (20.59%), breast (18.25%), prostate (7.13%), endometrium (6.47%) and colon and rectum (5.71%). We believe that the figure reported here represents an underestimate of the frequency of malignant tumours seen in the hospital and recommend the establishment of hospital- and population-based cancer registries to ensure proper documentation of malignant diseases within the region.

Breast Pathology and Reduction Mammaplasty

Breast cancer is the tumor with the highest prevalence and incidence in women. Reduction mammaplasty is one of the most common procedures performed in Brazil by the plastic surgeon, and it is not uncommon for the surgeon to find a breast tumor during the operation or afterward, when the histopathological report is received. In this study, 2488 patient files were reviewed retrospectively. All patients had undergone reduction mammaplasty at the senior author's private clinic (the Ivo Pitanguy Clinic) between January of 1957 and December of 2002. Resected breast tissue was examined histopathologically. The objective of this study was to verify the occurrence of breast carcinoma found accidentally postoperatively. The senior author's team performed all of the operations and the same pathologist performed every histopathological examination. The histopathological test results were divided into two groups: benign lesions and tumors. The highest frequency of breast pathology was benign lesions, and of them, 80.8 percent involved fibrocystic changes and fibroadiposity. The tumor group was subdivided into benign tumors and malignant tumors. Among the benign tumors, fibroadenoma was the one most common, in 2.2 percent. The frequency of malignant tumors was 0.5 percent of all patients. Most of the histopathological lesions were found in patients between 30 and 50 years of age. A reduced number of patients had no lesions (3.7 percent). Lack of a pathological investigation or a cursory or hurried examination of any mammary tissue by the pathologist may overlook important lesions. In the analysis of these statistics, the concept of normal breast tissue was questioned.

Apoptosis and bcl-2 oncogene expression in Wilms' tumor.

Wilms' tumor (WT) usually has a good outcome, although a poor prognosis is often related to more advanced stages and anaplastic features. Apoptosis occurs with variable frequency in malignant tumors, and may have a role in reducing their growth rate. The bcl-2 proto-oncogene inhibits apoptosis, and the consequent increase in the number of cells may play a role in the development of tumors. The aim of this study was to analyze the role of apoptosis and bcl-2 expression in WT. Twenty-six resected WT specimens were studied; 12 patients had stage I tumor, 4 stage II, 5 stage III, 3 stage IV, and 2 stage V. Twenty-three tumors were classified as favorable histology (FH) and 3 as unfavorable (UH). The mean follow-up was 34 months; 22 patients were alive and 4 were dead (2 with FH: 1 stage III and 1 stage IV, and 2 with UH stages 4). Apoptosis was detected by the in-situ end-labelling technique; bcl-2 expression was detected by immunohistochemistry. An apoptotic index (AI) was calculated as the ratio of apoptotic to normal cells in each specimen. The AI was lower in higher tumor stages, with a significant difference between stages I and IV (P < 0.05). In cases with UH, Al was lower than in tumors with FH (P < 0.01). The AI was also lower in patients who died than in those who survived (P < 0. 01). In all specimens no correlation between AI and bcl-2 expression was observed. Progression to advanced stages of WT and a poor prognosis f anaplastic tumors may be linked with disruption of the mechanisms that control apoptosis. Bcl-2 does not play a role as a regulator of apoptosis in WT, other oncogenes and tumor-suppression genes may be more involved in inhibiting apoptosis in WT.

Detection of p53 and histopathological classification of skin tumours induced by halogen lamps in hairless mice.

Skin lesions induced by exposure of three strains of female hairless mice to the light emitted by uncovered halogen quartz lamps were subjected to histopathological analysis. We examined 170 representative specimens out of a total of 597 skin lesions, i.e. 38 out of 74 SKH-1 mice, 110 out of 472 MF-1 mice, and 42 out of 51 C3H mice. The results provided evidence of various types of alterations, including preneoplastic changes, such as epidermal hyperplasia, and benign tumours, such as papillomas, as well as tumours with an increasing degree of malignancy, i.e., keratoacanthoma-like tumours, appendage/basal tumours, actinic keratoses/carcinomas in situ, and squamocellular carcinomas. SKH-1 was the most sensitive strain to the far-ultraviolet wavelengths delivered by halogen lamps, as shown not only by the shortest latency time and the highest multiplicity of skin lesions but also by the highest frequency of malignant tumours. Some areas of atypical melanocyte proliferation were only detected in C3H pigmented mice. Eighty-two of the lesions excised from MF-1 mice were additionally examined for p53 protein by immunohistochemical methods. Formalin-fixed, paraffin-embedded sections and frozen sections were analyzed in parallel by using polyclonal CM-1 antibody and monoclonal PAb240 antibody, respectively. A positive response for p53 was only observed in squamocellular carcinomas, and was related to the size of cancers; in fact, six out of 10 cancers of 10-30 mm in diameter were positive, whereas all 16 cancers of 2-9 mm in diameter were negative. All six positive squamocellular carcinomas were detected by using the CM-1 antibody, which recognizes both wild-type and mutant forms of p53 protein, and five of them were also positive with the PAb 240 antibody, which only recognizes the mutant form. Thus, p53 mutation appears to be a late event in the development of halogen-induced skin tumours in hairless mice, requiring a severe degree of malignancy and an advanced stage of the neoplastic mass growth.

Frequency of malignant tumours in diabetes mellitus.

The frequency of malignant tumours found at post mortem in 14,465 non-diabetics and 1,568 diabetics was surveyed. The different incidence of cancer in the two groups was very significant from the statistical point of view but the type of treatment of diabetes did not appear to have any influence on the incidence of malignancies.

Malignant tumors in psychotic patients. I. Studies of incidence.

The observation that malignant tumors are rare among patients in psychiatric hospitals has been reported frequently.* More recently, however, it has been contended that the frequency of malignant tumors is just as high among psychotics as in the general population and that the previous notion was based on a misleading statistical method.† However, the observations reported in both these groups of papers were based on mortality records, and it appears necessary to check the validity of the published opinions and conclusions by studying, in the setting of a large psychiatric hospital, the annual incidence of malignant tumors, that is, the number of cases first diagnosed during the study year. The present study is, as far as it could be ascertained, the first dealing with this aspect of the problem. Present Investigation During a three-year period from Dec. 31, 1951, to Dec. 31, 1954, a total of 46 cases of malignant