Clinicopathological and interphase cytogenetic analysis of desmoid tumours

 

Aims:

Recurrence of desmoid tumours is difficult to predict from only histological findings. In this study, immunohistochemistry for counting stromal blood vessels and proliferative activity, DNA flow cytometry, and interphase cytogenetic analysis of chromosome 8 by fluorescence in-situ hybridization (FISH) were performed to assess the correlation between their parameters and the recurrence of desmoid tumours.  

Methods and results:

The cases examined included 16 extra-abdominal desmoid and eight abdominal desmoids, comprising 14 recurrent and 10 non-recurrent cases. Eleven (69%) of the 16 extra-abdominal desmoids and three (38%) of the eight abdominal desmoids recurred. Patients with recurrent lesions (mean age, 20 years) were younger than those with non-recurrent tumours (34 years). Histologically, tumours with hypervascular areas frequently recurred after surgery in comparison with those with hypovascularity. There was no significant correlation between tumour size, the labelling index of the proliferating cell nuclear antigen (PCNA) and the recurrence. In flow cytometric analysis, all the cases examined showed a diploid pattern. The FISH study revealed that the incidence of trisomy 8 was significantly higher in the recurrent (72.7%) than in the non-recurrent cases (12.5%).  

Conclusions:

These results suggest that a subgroup of desmoid tumours at risk of recurrence may be hypervascular lesions associated with trisomy 8.     

Granular cell dermatofibroma

 

Aims:

To describe a series of five granular cell dermatofibromas as an unusual and rare manifestation of fibrohistiocytic tissue response.  

Methods and results:

Five granular cell dermatofibromas were collected out of 136 tumours filed as granular cell tumours. Clinically, all lesions occurred on the shoulder or back of middle-aged adults (two women, three men), mostly with the clinical diagnosis of a fibrohistiocytic lesion. Histology revealed well-circumscribed, dermal to subcutaneous lesions dominated by periodic acid–Schiff (PAS) positive, granular cells. Acanthosis above, as well as storiform arrangement of spindle cells, sclerotic collagen and some interspersed lymphohistiocytic infiltrate at the periphery of the lesion, indicated the fibrohistiocytic origin. Lesions showed prominent reactivity with NK1C3 (CD57), as well as for macrophage markers KiM1p and KP1 (CD68). In contrast to classic Schwannian/neurogenic granular cell tumours, granular cell dermatofibromas were S100 protein negative, but showed variable reactivity for factor XIIIa (10–50%) in 4/5, for smooth muscle specific actin (10–50%) in 2/5 and with E9 (10–30%) in 3/5 lesions. Electron microscopy in one case revealed large pools of phago-lysosomes and variably sized glycogen granules in granular cells.  

Conclusion:

Our series delineates granular cell dermatofibroma as a distinct clinicopathological variant of fibrohistiocytic tissue response which needs to be distinguished from other tumours with granular cell features.     

Expression of c-Met correlates with grade of malignancy in human astrocytic tumours: an immunohistochemical study

 

Aims:

Recent studies suggest the involvement of hepatocyte growth factor/scatter factor (HGF/SF) in glioma cell invasion and tumour progression. We investigated the distribution and rate of tumour cells that express c-Met protein, which is the cell-surface receptor for HGF/SF, in astrocytic tumours. The type of cells that express c-Met in tumour tissues was also identified.  

Methods and results:

c-Met expression was screened immunohistochemically in a total of 43 astrocytic tumours, including 14 low-grade astrocytomas (A), 13 anaplastic astrocytomas (AA) and 16 glioblastoma multiforme (GBM). c-Met reactivity was demonstrated predominantly in the cytoplasm of tumour cells. Bizarre large tumour cells tended to stain intensely. Higher c-Met expression levels (≥ 2 +, more than 25% cells were positive) were noted in 21.4% of (A) vs. 53.8% in (AA) and 87.5% in (GBM) ( P  < 0.001), indicating a clear relationship between c-Met protein staining and higher grade astrocytic tumours. Moreover, c-Met immunoreactivity was also shown in tumour microvasculature, reactive astrocytes, and neurones in the cortex infiltrated by glioma cells. In 85.7% of cases containing infiltrated cortex, neurones were positive vs. no neurones in non-neoplastic regions ( P  < 0.002).  

Conclusions:

This evidence suggests that c-Met expression in the brain could be associated with astrocytoma progression and also reactive process. Immunohistochemical determination of c-Met-expressing cell types helps to understand possible roles of c-Met in tumour tissues.     

p53 tumour suppressor gene protein expression in early and advanced gallbladder carcinoma

 

Aims:

Gallbladder carcinoma is one of the most frequent malignant tumours occurring in Chile and the mortality rate in both sexes ranks among one of the highest in the world. Mutation of p53 tumour suppressor gene has been demonstrated in many tumours. Our aim was to determine protein expression of p53 gene in early and advanced gallbladder carcinoma.  

Methods and results:

Protein expression of gene p53 was studied by immunohistochemical means in 191 gallbladder carcinomas (157 primary tumours, 34 metastases) and 25 controls. In 86 out of 191 cases (45%), protein expression of gene p53 was observed. Differences related to sex, age, or race were not observed. All gallbladder controls were negative. Twenty-five per cent of well-differentiated tumours were p53 positive, while moderate or poorly differentiated carcinomas reached 50% ( P  = 0.04). p53 expression was observed in 23.5% of early carcinomas and in 48.2% of advanced carcinomas ( P  = 0.01). No differences between primary tumours and metastasis were demonstrated.  

Conclusions:

Protein expression of p53 tumour suppressor gene is observed in 45% of gallbladder carcinomas. The absence of expression in controls and in normal mucosa adjacent to tumours suggests its utility in differentiating atypical gallbladder epithelia from neoplastic lesions.     

Expression of stratified epithelial-type cytokeratins in hyalinizing trabecular adenomas supports their relationship with papillary carcinomas of the thyroid

 

Aim:

To evaluate the cytokeratin pattern of expression of hyalinizing trabecular adenomas and to verify whether or not these tumours, that share morphological features with papillary carcinomas, present the stratified epithelial-type cytokeratins commonly found in ordinary papillary carcinomas.  

Methods and results:

This study consisted of the immunohistochemical detection of simple and stratified epithelial type cytokeratin filaments in a series of six hyalinizing trabecular adenomas, three papillary carcinomas with a trabecular growth pattern and two carcinomas combining hyalinizing trabecular and papillary patterns. Simple epithelial-type cytokeratins 7, 8, 18 and 19 were found in every case. Expression of the stratified epithelial-type cytokeratins 1, 5/6 and/or 13 was detected in four hyalinizing trabecular adenomas.  

Conclusion:

Based on this, as well as on the cytological features and on the frequent co-occurrence of hyalinizing trabecular adenoma and papillary carcinoma, we suggest that the former lesion may be considered a peculiar encapsulated variant of papillary carcinoma.     

Reproducible and highly sensitive detection of the broad spectrum epithelial marker keratin 19 in routine cancer diagnosis

 

Aims:

In this study the recently developed keratin 19 antibody RCK108 is biochemically and immunohistochemically characterized. Its applicability as a keratin marker in routinely processed histological tissue specimens is assessed.  

Methods and results:

The keratin 19 antibody RCK108 antibody was tested on normal and malignant routinely formalin-fixed, paraffin-embedded tissue specimens. It stains most, although not all, glandular epithelia and showed (focal) reactivity in the basal cell compartment of stratified epithelia. It was found to react with most epithelial tumours, including adenocarcinomas, squamous cell carcinomas and endocrine tumours of various origins.  

Conclusions:

Its reproducible and highly sensitive staining characteristics make RCK108 a useful antibody to be applied as a broad epithelial marker for carcinoma detection in routinely processed paraffin sections. As such, RCK108 is a specific reagent for practically all epithelial tumours. A few types of epithelial malignancies, known not to contain keratin 19, were negative for RCK108. Therefore the antibody is also useful in some narrow differential diagnostic considerations such as cholangiocellular carcinoma (RCK108 positive) vs. hepatocellular carcinoma (RCK108 negative). Another important feature of this antibody is that it shows very little reactivity in mesenchymal tissues, or mesenchymally derived tumours, as is frequently described for other keratin antibodies. A few leiomyosarcomas showed sporadic reactivity.     

Multinucleated stromal giant cells of testis

 

Aims:

This study documents the frequency of multinucleated stromal giant cells within the interstitium of the testis and looks for possible aetiological reasons for this occurrence.  

Materials and methods:

We examined sections of testes from 150 unselected autopsy cases finding stromal giant cells in 43%. An aetiological association between the occurrence of multinucleated stromal giant cells in this site and hormonal or other pathogenetic influences could not be established.  

Conclusions:

In many instances, this occurrence appears to be an age related phenomenon.     

Prognostic value of high serum levels of CA-125 in malignant secretory peritoneal mesotheliomas affecting young women. A case report with differential diagnosis and review of the literature

 

Aims:

Very few cases of diffuse, malignant, peritoneal mesothelioma have been reported in young women. Distinction between peritoneal mesothelioma and serous epithelial tumours, including papillary serous carcinomas and borderline serous tumours, can be difficult. Differential diagnosis based on clinical appearance and imaging techniques is broad and inconclusive, thus the diagnosis must be confirmed by histological examination. Because the vast majority of tumours involving the peritoneal and serosal surfaces are due to primary or metastatic serous epithelial tumours, there is a tendency on the part of pathologists to disregard the possibility of mesothelioma when examining a biopsy or excision specimen. This is especially likely to occur when mesothelioma is associated with highly elevated serum levels of CA-125, which is the typical tumoral marker of epithelial serous tumours from the ovary. The association between peritoneal mesothelioma and high serum levels of CA-125 has been reported in the literature only in two cases.  

Case details:

In order to avoid a misdiagnosis of this neoplasm we describe a new case of peritoneal mesothelioma in an 18-year-old woman with high serum levels of CA-125.  

Conclusions:

Besides its clinicopathological characteristics and its histological, immunohistochemical and ultrastructural features, we describe its biological behaviour, which seems to be worst when CA-125 levels are high.     

Mammary epidermoid inclusion cysts after wide-core needle biopsies

 

Aims:

To investigate the prevalence of squamous epidermoid inclusion cysts after wide-core needle biopsy.  

Methods and results:

Epidermoid inclusion cysts were found in five of 17 surgical excisions (29%) after preliminary wide-core needle biopsies in a 7-month period. Thereafter they were not seen in 26 subsequent postwide-core surgical excisions in a period of 6 months.  

Conclusions:

The cysts appear to be an iatrogenic complication of wide-core biopsy, and need morphological recognition in order to avoid confusion with spontaneous squamous metaplasia of benign or malignant breast epithelium. Longer term implications are unknown.     

Rapid verification of the identity of questionable specimens using immunohistochemistry with monoclonal antibodies directed against HLA-class I antigens

 

Aims:

A case report is presented in which an unexpected pathological diagnosis raised the possibility that biopsies of two patients were mixed-up. Since these biopsies were obtained from kidney transplant patients, the HLA-typings of both patients were known.  

Methods and results:

We developed an immunohistochemical method using HLA-class I specific monoclonal antibodies to recognize the donor and recipient antigens in these biopsies. Using this method we could confirm the identity of the patients of whom the biopsies had been taken.  

Conclusions:

This method, which uses the highly polymorphic HLA-system, is potentially useful for rapid and easy verification of the identity of specimens if a mix-up is suspected.     

Gastrointestinal tumour masses due to multiple myeloma: a pathological mimic of malignant lymphoma

 

Aims:

To describe and evaluate two cases of gastrointestinal involvement by multiple myeloma.  

Methods and results:

Clinical details were obtained from patients records and routine histopathological sections were correlated with haematological and immunohistochemical investigations. As shown in the accompanying illustrations, myeloma manifests as large, atypical, non-cohesive cells which may mimic high-grade lymphoma.  

Conclusions:

Extraskeletal spread of multiple myeloma occurs more frequently than is currently recognized, but clinical involvement of gut is rarely reported. Gut involvement may occur soon after initial diagnosis of myeloma and may be of serious clinical consequence. Histologically, it may mimic high-grade lymphoma. Failure to recognize myelomatous involvement of gut may result in inappropriate surgery or oncological therapy.     

Thyroid carcinoma associated with familial adenomatous polyposis

 

Aims:

Thyroid carcinoma is an extracolonic manifestation that is present in about 1% to 2% of patients with familial adenomatous polyposis (FAP). Less than 100 cases have been reported in detail. We have investigated the suggestion that FAP associated thyroid carcinoma is significantly different morphologically from both papillary and follicular types and can be considered as a separate entity.  

Methods and results:

Specimens from three patients with FAP associated thyroid tumours, all but one having single nodules, have been analysed. All three patients belonged to an extended kindred (23 siblings in four generations) who had genetic analysis and intensive screening for thyroid nodules. Seven patients had the same APC mutation at codon 1061. Pathological examination revealed a typical papillary carcinoma, encapsulated variant, in all patients, with follicular areas in one case. All thyroid specimens, in addition to histological and immunohistological examinations, were also specifically studied for activation of the RET-PTC oncogene, that seems to be restricted to papillary thyroid carcinoma. Two of the three patients had RET-PTC activation (PTC₁ isoform).  

Conclusions:

The findings suggest that the tumours were certainly papillary, at least in the present kindred. Further studies in different families are required for a better understanding of this peculiar tumour and of its biological behaviour.     

Hepatic stem-like cells in hepatoblastoma: expression of cytokeratin 7, albumin and oval cell associated antigens detected by OV-1 and OV-6

 

Aims:

In a recent study we described a population of small epithelial cells (SEC) in human hepatoblastoma that exhibit ultrastructural features of the oval cells of rodents. Both SEC and oval cells are immunoreactive for cytokeratin 7, a marker of biliary differentiation, and it was postulated that SEC, like oval cells, are closely related to hepatic stem cells. This study was undertaken to investigate whether SEC also exhibit immunolabelling for albumin, a marker of hepatocytic differentiation, and to determine whether other antigens typical of oval cells are detectable in hepatoblastoma.  

Methods and results:

Hepatoblastomas of various subtypes were investigated by electron microscopy, and by immunohistochemistry with the monoclonal antibodies OV-1 and OV-6, which recognize antigens associated with oval cells. Double-labelling for cytokeratin 7 and albumin was carried out by immuno-electron microscopy. OV-1 stained scattered cells in seven of 12 tumours investigated and OV-6 in nine. On immunoelectron-microscopic investigation, SEC exhibited labelling for both cytokeratin 7 and albumin.  

Conclusions:

The results demonstrate that antigens associated with oval cells are found in certain cells in hepatoblastoma. SEC, like oval cells, co-express markers for hepatocytic and biliary differentiation. The findings further support the hypothesis that SEC are closely related to the putative bipotent hepatic stem cell, which, by definition, gives rise to both hepatocytes and biliary epithelial cells.     

Carcinosarcoma of the oesophagus showing neuroendocrine, squamous and glandular differentiation

 

Aim:

A case of oesophageal carcinosarcoma occurring in a previously fit, 64-year-old man is reported.  

Case summary:

The carcinomatous component displayed neuroendocrine, squamous and glandular differentiation; the sarcomatous component showed no specific features of differentiation. In-situ squamous carcinoma was present in the adjacent squamous mucosa. The most superficial part of the invasive tumour consisted of carcinosarcoma with a predominant neuroendocrine epithelial component. Squamous carcinoma without an accompanying sarcomatous component occupied most of the deeper part of the tumour, suggesting outgrowth of this tumour type by a selective growth advantage.  

Conclusion:

We speculate that further tumour growth might have led to complete replacement of the tumour by pure squamous carcinoma, and that other advanced oesophageal squamous carcinomas might have had their origin in a short-lived carcinosarcomatous phase.     

Large cell neuroendocrine carcinoma of the thymus

 

Aim:

We highlight the occurrence of an unusual neuroendocrine tumour, a large cell neuroendocrine carcinoma, arising from the thymus.  

Case details:

A 68-year-old man with a history of cigarette smoking had a large mediastinal tumour arising from the thymus removed. Two years later the tumour recurred; it was debulked surgically but the patient died 2 months later. Histological examination of both tumour specimens revealed a tumour with an endocrine pattern, composed of large pleomorphic cells with large nuclei and prominent nucleoli. The mitotic count ranged from 19 to 26 per 10 high-power fields and large tracks of coagulative tumour necrosis were present. The tumour cells were strongly positive for neuron-specific enolase (NSE), chromogranin, CAM5.2 and AE1/3, with cytoplasmic dot-like accentuation for the latter three markers. The tumour fulfilled the criteria for a diagnosis of large cell neuroendocrine carcinoma.  

Conclusions:

Large cell neuroendocrine carcinoma should be distinguished from atypical carcinoid and small cell carcinoma. It is a distinctive neuroendocrine malignancy with a prognosis between that of atypical carcinoid and small cell carcinoma, and needs to be treated aggressively.     

Retrieved endogenous biotin: a novel marker and a potential pitfall in diagnostic immunohistochemistry

 

Aim:

Antigen retrieval (AR) procedures are based on the effect of heating (by either microwave or pressure cooking treatments) on routinely fixed and paraffin embedded tissues. We observed that AR procedures restore the reactivity of endogenous biotin (EB) and report on the distribution of EB following AR in a series of routinely fixed and embedded tissues.  

Methods and results:

Following pressure cooking or microwave treatments, a simple streptavidin–peroxidase staining revealed retrieved endogenous biotin (REB) in normal tissues (such as liver, kidney and adrenal cortex), in oxyphylic cells and in some tumours, especially in carcinomas of the kidney and of the adrenal cortex. In formalin-fixed (but not in alcohol-fixed) tissue sections, the heating procedures caused an intense and finely granular cytoplasmic reaction, following a routine streptavidin-conjugated peroxidase treatment. The staining was prevented by blocking of EB by a sequential avidin–biotin treatment.  

Conclusions:

Retrieval of EB reactivity can cause pitfalls in diagnostic immunohistochemistry but, alternatively, it might also constitute a useful and novel diagnostic marker.     

Stereological estimates of the nuclear/cytoplasmic ratio and star volume on fibreoptic biopsies are of prognostic value for survival in a preliminary study of advanced squamous cell carcinoma of the lung

 

Aims:

This study evaluated the role of morphometric and clinical parameters in establishing the prognosis of patients submitted to radiotherapy for advanced squamous cell carcinoma of the lung.  

Methods and results:

Morphometric studies were performed by point counting techniques. Forty patients were included in this study. Group 1 patients ( n  = 22) were those with survival equal to or less than 6 months; group 2 ( n  = 10) patients had a survival of 7 to 12 months; and group 3 ( n  = 8) included patients with survival greater than 12 months. To characterize these three groups of patients, models combining categorical and continuous variables were constructed by means of discriminant analysis. Weight loss, histological grade, nuclear/cytoplasmic ratio and star volume of the nuclei were selected during the backward procedure as relevant variables to characterize the three groups of patients. The overall sensitivity of the model was 90%.  

Conclusions:

Our results indicate that histopathological data may help to predict prognosis in patients with advanced squamous cell lung carcinoma, and encourage the use of morphometric procedures in histopathological analysis of this type of lung tumour.     

Intravascular lymphomatosis: a clinicopathological study of two cases presenting as an interstitial lung disease

 

Aims:

Intravascular lymphomatosis is an uncommon type of non-Hodgkin's lymphoma characterized by intravascular proliferation of neoplastic lymphoid cells. Although the tumour is basically a systemic disease, eventually involving multiple organs, primary presentation in the lung is rare.  

Methods and results:

We describe the clinicopathological features of two patients with intravascular lymphomatosis presenting in the lung. One patient complained of fever, headache and chest pain; the other, of dyspnoea on exertion and headache. Both patients showed reticulonodular density on chest radiography and decreased diffusion capacity. Lung biopsy showed features characteristic of intravascular lymphomatosis. Malignant lymphoid cells were CD30 positive T-cells of anaplastic large cell type in one patient and B-cells of large cell type in the other. There was a poor response to chemotherapy and both patients died of the disease within 3 months of diagnosis.  

Conclusions:

These cases and 10 previous reports illustrate the need to include intravascular lymphomatosis in the differential diagnosis of interstitial lung disease.     

Identification of oncocytic lesions of salivary glands by anti-mitochondrial immunohistochemistry

 

Aims:

To evaluate the immunohistochemistry using an anti-mitochondria antibody in the investigation of various oncocytic lesions of the salivary glands.  

Methods and results:

Ten cases of adenolymphoma (Warthin's tumour) and one case each of benign oncocytoma and oncocytic carcinoma of the salivary glands were examined. Normal salivary glands were also tested. They were investigated immunohistochemically using mouse monoclonal antibody against human mitochondria. In normal salivary glands, epithelial cells of the striated ducts showed a thick linear immunoreactivity, which corresponded well to the intracytoplasmic distribution pattern of mitochondria. In addition, a small number of swollen epithelial cells showing an intense, finely granular immunoreactivity in the cytoplasm were scattered in the ductal system and acini ('oncocytic metaplasia'). Almost all neoplastic cells involved in adenolymphoma, benign oncocytoma, and oncocytic carcinoma showed an intense, finely granular immunoreactivity in the cytoplasm.  

Conclusions:

Immunohistochemistry using the anti-mitochondria antibody proved to be a highly sensitive and specific method for light microscopic identification of mitochondria and superior to routine H & E or PTAH stain especially in the detection of isolated oncocytic cells.     

Rhabdomyomatosis of the newborn lung unassociated with other malformations

 

Aims:

To describe a case of rhabdomyomatosis of the lung unassociated with other external or visceral malformations in a newborn infant.  

Methods and results:

A 26 weeks' gestation newborn male with no relevant medical or family history presented a well-circumscribed solid area in the posterior mediastinum occupying the upper lobe of the right lung. The possibility of neuroblastoma or an extralobar pulmonary sequestration were excluded after laboratory and arteriographic studies. No visceral anomalies were found. At the age of 9 months the patient underwent a partial lobectomy, and he is free of disease 39 months after surgery. Histological examination demonstrated the presence of numerous bundles of striated fibres arranged haphazardly in the pulmonary interstitium in a background of a type-II congenital cystic adenomatoid malformation-like morphology of the resected lung.  

Conclusion:

The presence of striated muscle fibres in the lung not necessarily represents a lethal congenital malformation. As this case shows, rhabdomyomatosis of the lung can affect a single pulmonary lobe, and resection of the affected lung parenchyma may be curative. It is important for pathologists to be aware of this entity, although it is exceptional, and to include it in the differential diagnosis of pulmonary masses in the newborn lung.