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Background: This study was performed in knowledge of the increasing gap between breast disease treatment in countries with restricted resources and developed countries with increasingly sophisticated examination methods., Methods: The authors present the analysis of a breast disease register consisting of diagnostic cases from Mazar e Sharif and Herat in 2018 and 2019. The study comprises a total of 567 cases, which were presented to experts via telemedicine for final diagnosis. 62 cases (10.9%) were excluded due to inacceptable data or insufficient image quality. These data provided by daily diagnostic classification were used for the built-up of a profile for each frequent breast disease and a breast cancer register. All images and cases were seen by at least 3 independent experts. The diagnoses were made in 60% of cases by cytology of fine needle aspiration and in 40% by histological images., Results: For each entity of breast diseases (e.g., fibroadenoma), a profile of context variables was constructed allowing to assist medical decisions, as "wait and see," elective surgery or immediate surgical intervention with R0 (complete) resection. These "profiles" could be described for fibroadenoma, mastitis, galactocele, fibrous-cystic disease, and invasive breast cancer., Conclusions: The presented preliminary data set could serve as a cost-effective basis for a North Afghan breast cancer registry, with option to extent to a national model. These preliminary data are transformed in profiles of breast diseases, which are used by the local physicians in charge of breast disease patients. Each new case can be compared by the local treating physician with the profile of all preceded cases with the same diagnosis., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 Gerhard Stauch et al.)

Introduction: We describe the use of telepathology in countries with restricted resources using two diagnosis assistance systems (Isabel and Memem7) in addition to the diagnoses made by experts in pathology via the iPath-Network., Methods: A total of 156 cases, largely from Afghanistan, were analysed; 18 cases had to be excluded because of poor image quality., Results: Of the remaining 138 cases (100%), a responsible physician provided a tentative diagnosis for 61.6% of them. With a diagnosis from a consultant pathologist, it was then possible to make a definite diagnosis in 84.8% of cases on the basis of images taken from hematoxylin and eosin staining sections alone. The use of the diagnosis assistance systems resulted in an ordered list of differential diagnoses in 82.6% (IsabelHealth) and in 74.6% (Memem7) of cases, respectively. Adding morphological terminology reduced the list of possible diagnoses to 52.2% (72 cases, Memem7), but improved their quality., Discussion: In summary, diagnosis assistance systems are promising approaches to provide physicians in countries with restricted resources with lists of probable differential diagnoses, thus increasing the plausibility of the diagnosis of the consultant pathologist.

We present a unique case of infectious mononucleosis attended with transient asymptomatic BK virus (BKV) manifestation in the urine of an immunocompetent caucasian boy without kidney dysfunction. The urine sediment showed abundant decoy cells initially misdiagnosed as malignant cancer cells. This case demonstrates that the occurrence of polyoma-BKV bearing decoy cells is self-limiting and not necessarily associated with overt kidney disease in an immunocompetent child. The shedding of decoy cells into the urine might be promoted by viral co-infections modulating the host's immune response such as infectious mononucleosis.

Objective: In this study, the efficiency of telemedical consulting with regard to fine needle aspirates from space-occupying lesions (SOLs) of the liver is investigated for the first time., Study Design: The study includes fine needle aspirations from 62 patients, 33 with hepatocellular carcinoma (HCC) and 29 with non-hepatic tumors. Using the Internet-based iPath system, the initial pathologist submitted 1-8 images from smears and cell block sections. One consultant assessed the cytological and another one the histological images. Both made their diagnoses independent of each other. A final diagnosis was made by immunochemistry of cell block sections. The cytological images were analyzed retrospectively for the occurrence of the most typical HCC indicators. The number of these indicators was related to the initial diagnoses of the three pathologists, and possible reasons for diagnostic errors were analyzed based on this analysis., Results: The accuracy of the preliminary telemedical diagnoses regarding HCC was 82.0% for the cytological images and 87.7% for the histological images. Most of the false diagnoses occurred in tumors with unusual cytological and histological patterns., Conclusions: Telemedical consulting is a valuable tool to obtain a second opinion. However, for improvement of the diagnosis of HCC, supplementary immunochemical tests are necessary.

Background: The iPath telemedicine platform Basel is mainly used for histological and cytological consultations, but also serves as a valuable learning tool., Aim: To study the level of accuracy in making diagnoses based on still images achieved by experienced cytopathologists, to identify limiting factors, and to provide a cytological image series as a learning set., Method: Images from 167 consecutive cytological specimens of different origin were uploaded on the iPath platform and evaluated by four cytopathologists. Only wet-fixed and well-stained specimens were used. The consultants made specific diagnoses and categorized each as benign, suspicious or malignant., Results: For all consultants, specificity and sensitivity regarding categorized diagnoses were 83-92 and 85-93%, respectively; the overall accuracy was 88-90%. The interobserver agreement was substantial (κ = 0.791). The lowest rate of concordance was achieved in urine and bladder washings and in the identification of benign lesions., Conclusion: Using a digital image set for diagnostic purposes implies that even under optimal conditions the accuracy rate will not exceed to 80-90%, mainly because of lacking supportive immunocytochemical or molecular tests. This limitation does not disqualify digital images for teleconsulting or as a learning aid. The series of images used for the study are open to the public at http://pathorama.wordpress.com/extragenital-cytology-2013/., (© 2014 S. Karger AG, Basel.)

Molecular markers reliably predicting failure or success of Bacillus Calmette-Guérin (BCG) in the treatment of nonmuscle-invasive urothelial bladder cancer (NMIBC) are lacking. The aim of our study was to evaluate the value of cytology and chromosomal aberrations detected by fluorescence in situ hybridization (FISH) in predicting failure to BCG therapy. Sixty-eight patients with NMIBC were prospectively recruited. Bladder washings collected before and after BCG instillation were analyzed by conventional cytology and by multitarget FISH assay (UroVysion, Abbott/Vysis, Des Plaines, IL) for aberrations of chromosomes 3, 7, 17 and 9p21. Persistent and recurrent bladder cancers were defined as positive events during follow-up. Twenty-six of 68 (38%) NMIBC failed to BCG. Both positive post-BCG cytology and positive post-BCG FISH were significantly associated with failure of BCG (hazard ratio (HR)= 5.1 and HR= 5.6, respectively; p < 0.001 each) when compared to those with negative results. In the subgroup of nondefinitive cytology (all except those with unequivocally positive cytology), FISH was superior to cytology as a marker of relapse (HR= 6.2 and 1.4, respectively). Cytology and FISH in post-BCG bladder washings are highly interrelated and a positive result predicts failure to BCG therapy in patients with NMIBC equally well. FISH is most useful in the diagnostically less certain cytology categories but does not provide additional information in clearly malignant cytology., (Copyright 2008 UICC.)

Aim: To investigate whether nuclear and cytoplasmic Maspin expression is associated with distinct clinicopathological parameters and TP53 expression in a representative series of primary non-small cell lung cancer (NSCLC)., Methods: Tissue microarrays (n=487) were used to immunohistochemically analyse expression of Maspin and TP53. Cytoplasmic and nuclear expression of Maspin was scored on the basis of the percentage of positive tumour cells. Univariate analysis of clinicopathological variables potentially affecting tumour-specific survival was performed., Results: Immunohistochemical Maspin expression (nuclear and cytoplasmic) was informative in 72.3% (352/487) of cases. Cytoplasmic and nuclear Maspin immunoreactivity in >or=10% of tumour cells was detected in 37.8% (133/352) and 65.3% (230/352) of informative cases, respectively. Nuclear and cytoplasmic Maspin staining was observed more frequently in primary squamous cell carcinomas than in other lung cancer types. Only nuclear Maspin immunoreactivity was significantly associated with positive TP53 staining. Cytoplasmic or nuclear Maspin expression was not associated with tumour-specific survival., Conclusion: Maspin expression was found both in the nucleus and the cytoplasm of NSCLC, more frequently in squamous cell carcinomas. However, no association with tumour-specific survival could be demonstrated.

Mesothelioma are primary malignant neoplasms of the serous membranes. They usually involve the pleura and rarely the pericardium, the peritoneum and the tunica vaginalis testis. About 90% are associated with exposure to asbestos. The exposure is generally occupational, an environmental inhalation of asbestos and asbestiform fibers in areas in Turkey has been observed and presents a major health problem. This report of a patient from Anatolia with peritoneal mesothelioma after environmental exposure outlines the importance of considering this pathology in the differential diagnosis of a Turkish patient presenting with ascites.

Objective: To evaluate MAGE tumor-associated antigen (TAA) expression in an extensive panel of normal and neoplastic tissues., Summary Background Data: TAAs of the MAGE family represent targets of active specific immunotherapy. Limited-size studies indicate that they are expressed in normal testis and tumors of different histologies. High-throughput tissue microarray (TMA) technology and MAGE TAA-specific monoclonal antibodies now allow us to comprehensively evaluate their expression in large numbers of tissues and to address clinical correlations., Methods: A TMA containing 3,520 samples from 197 different tissues and a non-small-cell lung cancer TMA including 301 specimens were stained using the MAGE TAA-specific monoclonal antibody 57B. For patients with squamous cell carcinoma of the lung, the dichotomous result (positive vs. negative) of MAGE TAA staining was used as a predictor variable along with other covariates in proportional hazard regression analysis of tumor-specific survival., Results: MAGE TAAs are expressed with frequencies ranging between 22.7% (larynx) and 50% of cases (lung) in squamous cell carcinomas from different anatomic areas and in large cell carcinomas of the lung (37.9%). The authors provide here the first description of MAGE TAA expression in basalioma (48.1%). To investigate the clinical significance of MAGE expression in a frequently positive tumor type, a non-small-cell lung cancer, TMA was then studied. In this TMA 43.2% of tumors were 57B positive. In patients with squamous cell carcinoma, MAGE TAA positivity was significantly correlated with a shorter tumor-specific survival in the proportional hazard regression analysis model., Conclusions: These data suggest novel potential therapeutic indications in different types of cancers. In lung squamous cell carcinoma, the significant association of MAGE TAA expression with poor prognosis suggests that patients with 57B-positive tumors may benefit from early, specific immunotherapy procedures.

A total of 9000 urine samples from 69 kidney transplant recipients were studied for differential diagnoses of transplant rejection and cyclosporin/tacrolimus toxicity. New-Sternheimer and Papanicolaou staining were used to differentiate cells in urine. We also employed an immunocytochemical technique for further identification of exfoliated cells. With New-Sternheimer and Papanicolaou staining, the predominance of proximal tubular cells was useful to differentiate cyclosporin/tacrolimus toxicity from acute rejection in cases of increased serum creatinine level. During rejection episodes, an increased number of mononuclear cells and renal epithelial cells were found. Immunocytochemical analysis showed a significant increase of CD2-, CD4- CD8-, CD25- and HLA-DR-positive cells with rejection. However, there was no relationship between Banff criteria rejection grade and the increase of mononuclear cells.

We report on a 17-year-old patient with severe bronchiolitis due to Mycoplasma pneumoniae infection. Despite an early 10-day course of clarithromycin, she developed progressive dyspnea, cough, fever, and severe obstructive ventilatory impairment. Sixteen days after onset of the disease a severe hemolytic anemia developed with only cold agglutinins positive at serologic screening. Thoracoscopic lung biopsy revealed diffuse bronchiolitis with suppurative intrabronchiolar inflammation, lymphohistiocytic "cuffing" of the bronchioli, and foam cell aggregates within neighboring alveoli. The infiltrate consisted mainly of CD3+, CD8+ lymphocytes and CD68+ macrophages. The diagnosis of Mycoplasma pneumoniae bronchiolitis was based on repeated complement fixation tests, which turned strongly positive only at day 74 after onset of the disease. Pulmonary function improved slowly under long-term prednisone treatment.

The case of a 44-y-old woman with HIV infection and cytomegalovirus retinitis in whom antiretroviral therapy (HAART) revealed pulmonary cryptococcosis is presented. Pulmonary cryptococcosis occurred simultaneously with immune recovery uveitis after starting HAART, showing that complex clinical pictures may arise from immunreconstitution diseases.

In a 59-year-old male patient, chronic dry cough and dyspnoea on exertion preexisting for several years became rapidly progressive within a few weeks prior to hospitalisation. He died one month after admission from respiratory failure. Three months before admission, history, pulmonary function tests, and computed tomography (CT) of the chest revealed no evidence of asthma, COPD, or any other lung disease. Clinical examination showed no clubbing, but end-inspiratory velcro-rales were audible over both lungs. Inhaled steroids and diuretics did not bring clinical amelioration. On admission there were basal consolidations, bronchiectases, and predominant fibrotic changes with honeycombing and subpleural thickening over both lungs, in the absence of any ground-glass pattern in the CT. At the same time lymphocytosis predominated in bronchoalveolar lavage (BAL). The search for pneumonia, viral infection, tumour, vasculitis, or a drug-related disorder remained negative. Pathological examination at autopsy showed nonuniform fibrosing alveolitis.

Background: Reactivation of polyomavirus type BK (BK virus) is increasingly recognized as a cause of severe renal-allograft dysfunction. Currently, patients at risk for nephropathy due to infection with the BK virus are identified by the presence of cells containing viral inclusion bodies ("decoy cells") in the urine or by biopsy of allograft tissue., Methods: In a retrospective analysis, we performed polymerase-chain-reaction assays for BK virus DNA in plasma samples from 9 renal-allograft recipients with BK virus nephropathy; 41 renal-allograft recipients who did not have signs of nephropathy, 16 of whom had decoy cells in the urine; and as immunocompromised controls, 17 patients who had human immunodeficiency virus type 1 (HIV-1) infection (stage C3 according to the classification of the Centers for Disease Control and Prevention) and who had not undergone transplantation., Results: In all nine patients with BK virus nephropathy, BK virus DNA was detected in the plasma at the time of the initial histologic diagnosis (a mean [+/-SD] of 46+/-28 weeks after transplantation) and during the course of histologically diagnosed, persistent BK virus disease. In three of the six patients with nephropathy who were studied serially after transplantation, BK virus DNA was initially undetectable but was detected 16 to 33 weeks before nephropathy became clinically evident and was confirmed by biopsy. Tests for BK virus DNA in plasma became negative and the nephropathy resolved after the doses of immunosuppressive drugs were decreased in two patients and after removal of the renal allograft in three patients. BK virus DNA was found in the plasma of only 2 of the 41 renal-allograft recipients who had no signs of nephropathy and in none of the patients with HIV-1 infection., Conclusions: Testing for BK virus DNA in plasma from renal-allograft recipients with use of the polymerase chain reaction is a sensitive and specific method for identifying viral nephropathy.

Invasive pulmonary aspergillosis (IPA) is a life-threatening infectious complication in neutropenic patients after high-dose chemotherapy or hematopoietic stem cell transplantation. Its diagnosis is mainly based on clinical symptoms, and radiological signs on thoracic CT scan. The value of bronchoscopy is controversial. We analyzed the diagnostic yield of bronchoscopy in 23 consecutive patients with histologically proven invasive pulmonary aspergillosis. In seven patients (30%) bronchoscopically obtained specimens were diagnostic for pulmonary fungal infection. Typical hyphae were detected by cytology in six patients and fungal cultures were positive in four cases. Patients with a positive bronchoscopic result presented more often with multiple changes on thoracic CT scan (71%; 5/7), but had received a lower median cumulative dose of amphotericine B (300 mg; 168-3010 mg) compared to patients with non-diagnostic bronchoscopy (25% multiple lesions (4/16); amphotericine dose 1100 mg, 260-2860 mg). The diagnostic yield of bronchoscopy was not associated with clinical symptoms or duration of neutropenia. Bronchoscopy allows the diagnosis of IPA in about one third of patients. Fungal cultures and cytological examination of intrabronchial specimens obtained during bronchoscopy have a high specificity, but its sensitivity is low. It is advisable to perform diagnostic bronchoscopy before starting antifungal therapy. Better diagnostic tools are urgently needed.

A 85-year-old woman was admitted to our hospital because of a presumtive diagnosis of pulmonary thromboembolism. The patient presented with a history of progressive dyspnoea and retrosternal pain. 3-4 weeks ago she had noticed a swollen left leg. On examination a 4/6-pansystolic murmur was found. An arterial blood gas analysis showed a reduced oxygen saturation. An electrocardiogram revealed deep S-waves in lead I and pathological Q-waves in lead III. The chest X-ray showed cardiomegaly, a pulmonary nodule and an ill-defined opacity inferioposteriorly. Ventilation-perfusion mismatch was demonstrated by lung ventilation-perfusion scanning. Transthoracic echocardiography showed pulmonary hypertension and tricuspid regurgitation. On the 20th hospital day the patient died from multi organ failure. Pulmonary thromboembolism secondary to deep venous thrombosis of the lower extremities was the most likely diagnosis. In view of the patients' history of night sweat, loss of appetite and weight loss a malignant process had to be taken into consideration. A tumor originating from the right ventricle, the right ventricular outflow tract or the pulmonary artery was compatible with the clinical picture of multiple pulmonary emboli. On autopsy a polymorph cellular sarcoma measuring 6 x 3 x 3 cm was found in the right ventricular outflow tract. Section of the lung revealed a single pulmonary metastasis and multiple thromboemboli of various age. Pulmonary artery sarcomas, as described in our case, are extremely rare. The prognosis is poor and often the diagnosis is only made on autopsy.

Polyomavirus (PV) exceptionally causes a morphologically manifest renal allograft infection. Five such cases were encountered in this study, and were followed between 40 and 330 d during persistent PV renal allograft infection. Transplant (Tx) control groups without PV graft infection were analyzed for comparison. Tissue and urine samples were evaluated by light microscopy, immunohistochemistry, electron microscopy, and PCR. The initial diagnosis of PV infection with the BK strain was made in biopsies 9+/-2 mo (mean +/- SD) post-Tx after prior rejection episodes and rescue therapy with tacrolimus. All subsequent biopsies showed persistent PV infection. Intranuclear viral inclusion bodies in epithelial cells along the entire nephron and the transitional cell layer were histologic hallmarks of infection. Affected tubular cells were enlarged and often necrotic. In two patients, small glomerular crescents were found. In 54% of biopsies, infection was associated with pronounced inflammation, which had features of cellular rejection. All patients were excreting PV-infected cells in the urine. PV infection was associated with 40% graft loss (2 of 5) and a serum creatinine of 484+/-326 micromol/L (mean +/- SD; 11 mo post-Tx). Tx control groups showed PV-infected cells in the urine in 5%. Control subjects had fewer rejection episodes (P<0.05) and stable graft function (P = 0.01). It is concluded that a manifest renal allograft infection with PV (BK strain) can persist in heavily immunosuppressed patients with recurrent rejection episodes. PV mainly affects tubular cells and causes necrosis, a major reason for functional deterioration. A biopsy is required for diagnosis. Urine cytology can serve as an adjunct diagnostic tool.

Mutations of the tumor suppressor gene p53 are the most common genetic alterations observed in human cancer. Loss of wild-type p53 function impairs cell cycle arrest as well as repair mechanisms involved in response to DNA damage. Further, apoptotic pathways as induced by radio- or chemotherapy are also abrogated. Gene transfer of wild-type p53 was shown to reverse these deficiencies and to induce apoptosis in vitro and in preclinical in vivo tumor models. A phase I dose escalation study of a single intratumoral injection of a replication-defective adenoviral expression vector encoding wild-type p53 was carried out in patients with incurable non-small cell lung cancer. All patients enrolled had p53 protein overexpression as a marker of mutant p53 status in pretreatment tumor biopsies. Treatment was performed either by bronchoscopic intratumoral injection or by CT-guided percutaneous intratumoral injection of the vector solution. Fifteen patients were enrolled in two centers, and were treated at four different dose levels ranging from 10(7) to 10(10) PFU (7.5 x 10(9) to 7.5 x 10(12) particles). No clinically significant toxicity was observed. Successful transfer of wild-type p53 was achieved only with higher vector doses. Vector-specific wild-type p53 RNA sequences could be demonstrated in posttreatment biopsies of six patients. Transient local disease control by a single intratumoral injection of the vector solution was observed in four of those six successfully transduced patients. There was no evidence of clinical responses at untreated tumor sites. Wild-type p53 gene therapy by intratumoral injection of a replication-defective adenoviral expression vector is safe, feasible, and biologically effective in patients with advanced non-small cell lung cancer.

Invasive pulmonary aspergillosis (IPA) is associated with a high mortality. In 27 consecutive neutropenic patients who underwent lung resection for suspected IPA, we analyzed preoperative diagnostic evaluation, operative procedure, perioperative management, histological findings, outcome concerning recurrence of aspergillosis, and survival to evaluate the morbidity and mortality of a surgical treatment of IPA. Seventeen patients with hematologic diseases had previously undergone high-dose chemotherapy and four stem cell transplantation. Six patients with aplastic anemia were treated with antilymphocyte globulin. IPA was suspected if localized infiltrates developed on thoracic CT scan, and fever persisted under antibiotic therapy in neutropenic patients. In only one case a diagnosis of IPA could be made preoperatively. Twenty patients underwent lobectomy and seven wedge resection. At day of surgery the neutrophil count was below 500 x 10(9)/L in 78% of patients, and the platelet count below in 50 x 10(9)/L in 58% of patients. Invasive fungal infection was confirmed histologically in 22 of 27 patients (81.5%); in five patients no fungal infection was documented. The median duration of surgery was 120 min. Postoperatively, patients stayed one night in the intensive care unit, and chest tubes were removed after 2 d. Within 7 d a median of four erythrocyte packs and two platelet packs per patient were replaced. Major surgical complications occurred in two patients (bronchial dehiscence; pleural aspergillosis). Minor surgical complications included prolonged chest tube drainage (recurrent pneumothorax, n = 2; air leakage, n = 1; hematothorax, n = 1), pleural effusion (n = 4), and seroma (n = 2). Postoperatively, two patients suffered from histologically proven disseminated aspergillosis (pleural aspergillosis, renal aspergilloma) and another patient from suspected orbital aspergillosis. At 30 d postoperative mortality was 11% and 3-mo survival was 77%. After lung resection, seven patients underwent stem cell transplantation without recurrence of IPA. In conclusion, we suggest lung resection is a therapeutic option for invasive pulmonary aspergillosis in neutropenic patients with hematologic diseases and is associated with a low surgery-related morbidity and mortality.

Human herpes virus 8 (HHV8) DNA has recently been detected in sarcoma tissue of patients with Kaposi's sarcoma. HHV8 DNA could also be found in bronchoalveolar lavage (BAL) fluid of patients with tracheobronchial Kaposi's sarcoma. To determine the specificity, sensitivity and predictive values of HHV8 DNA detection in the BAL for the diagnosis of pulmonary Kaposi's sarcoma, 100 consecutive BAL were prospectively analyzed for the presence of HHV8 DNA using a nested PCR assay. In addition, 19 BAL samples of 14 AIDS patients with cutaneous or visceral Kaposi's sarcoma were retrospectively investigated. The prospective group consisted of 79 BAL performed in immunocompromised and of 21 BAL in nonimmunocompromised patients. Four patients of the prospectively analyzed group undergoing six BAL showed tracheobronchial Kaposi's sarcoma at five bronchoscopies. All of the five BAL samples performed in these patients with endoscopically visible Kaposi's sarcoma were positive for HHV8 DNA. Following chemotherapy and antiretroviral treatment tracheobronchial Kaposi's sarcoma was no longer detectable at a subsequent bronchoscopy and HHV8 DNA in BAL became negative in one patient. One BAL sample of a HIV-positive patient with no evidence of Kaposi's sarcoma was HHV8 DNA-positive. The sensitivity, specificity, positive and negative predictive values of HHV8 detection for the diagnosis of tracheobronchial Kaposi's sarcoma were 100%, 98.9%, 83.3%, and 100%, respectively. Twelve of 19 BAL samples of the retrospective group were HHV8 DNA-positive. In this group, 10 patients undergoing a total of 14 BAL suffered from pulmonary Kaposi's sarcoma. HHV8 DNA was documented in 10 of these 14 BAL samples. In three BAL of this group HHV8 DNA was positive, but pulmonary Kaposi's sarcoma was diagnosed at a later stage. In conclusion, the detection of HHV8 DNA in BAL is restricted to patients with Kaposi's sarcoma and is highly sensitive and specific for pulmonary involvement of Kaposi's sarcoma.

Inactivation of the p53 gene plays a key role in tumour biology, probably through a disturbed cell cycle control and an increased genetic instability in p53-inactivated tumours. To learn more about the relationship between p53 alterations, proliferation and genetic instability (DNA aneuploidy) in lung cancer patients, specimens of 220 surgically resected lung carcinomas with clinical follow-up information were examined by immunohistochemistry (p53; CM1) and flow cytometry. Nuclear p53 positivity--found in 49.5% of the tumours--was associated with both high S-phase fraction (SPF) and DNA ploidy aberrations. SPF was higher in p53-positive tumours (15.9 +/- 10.2) than in p53-negative tumours (10.3 +/- 8.7; P = 0.03). The rate of p53 positivity was higher in 101 DNA-aneuploid and DNA-multiploid tumours (55%) than in 27 diploid and peridiploid carcinomas (33%; P = 0.0512). These results are consistent with an in vivo role of p53 inactivation for increased proliferative activity and development of genomic instability in lung cancer. There was no association between SPF and prognosis. Although prognosis was worse in DNA-aneuploid and multiploid tumours than in diploid, peridiploid and tetraploid carcinomas (P = 0.029), DNA ploidy was not an independent predictor of poor prognosis in multivariate analysis. These data show that DNA-flow cytometry has little prognostic value for patients with resected non-small-cell lung carcinoma.