Inflammatory Pseudotumor of the Liver: Report of Two Cases

Inflammatory pseudotumor of the liver is a very rare lesion. Herein we describe two cases of this entity which occurred in two women aged 22 and 49 years, respectively. Both cases were considered to be clinically malignant and only the histopathologic examination revealed the non-neoplastic nature of the disease. Ultrastructural and immunohistochemical studies further supported the evidence of a reactive disease.

Superficial acral fibromyxoma: a clinicopathological and immunohistochemical analysis of 12 cases of a distinctive soft tissue tumor with a predilection for the fingers and toes

AIM

Superficial acral fibromyxoma (SAFM) is a rare soft tissue tumor, recently delineated and documentated as a separate entity. We report 12 cases of SAFM observed in our department from June 2004 to June 2010 and highlight pathological features and differential diagnosis.

METHODS

Radiographic examination of the affected digit was performed in all patients. All the tumors were surgically excised under local anesthesia. Follow-up was made every 6-8 months for a maximum period of five years.

RESULTS

The patients consisted of 8 men and 4 women, age range 28-76 years (mean 51), presenting with a solitary mass or nodule located in the toes and fingers. Histologically the lesions were well circumscribed dermal nodules composed of stellate and spindle cells, arranged in a myxoid matrix. Very low grade atypia and a few mitotic figures were found in only one case. Neoplastic cells showed immunoreactivity for CD34 (12 patients). In contrast focally positive or negative staining was shown for the epithelial membrane antigen (EMA) and CD 99. Actin, S100 protein, HMB45 and cytokeratin were negative. In three cases marked hyperkeratosis and acanthosis of the epidermis was present. Pathological analysis confirmed the diagnosis of superficial acral fibromyxoma. No recurrences were observed even in a long term, 2-5 year follow-up.

CONCLUSION

Complete surgical excision of the tumors and a careful follow-up is suggested, despite the benign course previously reported.

Apolipoprotein D in CD34-positive and CD34-negative cutaneous neoplasms: a useful marker in differentiating superficial acral fibromyxoma from dermatofibrosarcoma protuberans

More recent techniques to characterize the genetic profile of soft-tissue tumors include the use of gene arrays. Using this technique, Apolipoprotein D (Apo D), a 33-kDa glycoprotein component of high-density lipoprotein, has been found to be highly expressed in dermatofibrosarcoma protuberans. To corroborate these results, we sought to ascertain the utility of Apo D by investigating its sensitivity and specificity in a variety of CD34-positive and CD34-negative cutaneous neoplasms including superficial acral fibromyxoma, sclerotic fibromas, and cellular dermatofibromas. Of interest, we found absence of Apo D expression in all four cases of superficial acral fibromyxoma. Of the remaining CD34-positive lesions, Apo D expression was noted in 35/36 (97%) cases of dermatofibrosarcoma protuberans, 3/5 (60%) giant-cell fibroblastomas, 4/4 (100%) sclerotic fibromas, 8/8 (100%) neurofibromas, and 1/1 (100%) solitary fibrous tumor. Of the CD34-negative lesions, Apo D expression was noted in 2/22 (9%) regular dermatofibroma, 23/45 (51%) cellular dermatofibroma, 10/10 (100%) malignant fibrous histiocytoma, 9/10 (90%) atypical fibroxanthoma, 7/8 (86%) cellular neurothekeoma, 9/9 (100%) malignant melanoma, 8/8 (100%) melanocytic nevi (100%), 0/2 superficial angiomyxoma, 0/15 fibromatosis, 0/1 nodular fasciitis, and 1/2 (50%) desmoplastic fibroblastomas. In summary, our findings indicate that Apo D expression is not specific to dermatofibrosarcoma protuberans. Its principal use as an immunohistochemical adjunct lies in its utility in differentiating superficial acral fibromyxoma from dermatofibrosarcoma protuberans. Although strong positive staining of Apo D in a markedly atypical fibrohistiocytic lesion is suggestive of atypical fibroxanthoma and/or malignant fibrous histiocytoma, further studies with the inclusion of other atypical spindled cell neoplasms are required to conclusively prove the same.

CD99 immunoreactivity in atypical fibroxanthoma and pleomorphic malignant fibrous histiocytoma: a useful diagnostic marker

Atypical fibroxanthoma (AFX), a benign lesion, and pleomorphic malignant fibrous histiocytoma (MFH) are thought to represent points along the same neoplastic spectrum but with different prognoses and treatments. Diagnosis based on histology and clinical parameters alone is sometimes difficult, and a reliable cost-effective immunohistochemical marker to help distinguish these lesions would be beneficial. The diagnosis of AFX or MFH was based upon published clinical and microscopic criteria. Formalin-fixed, paraffin-embedded tissues of 17 cases of AFX and 26 cases of MFH were immunostained with monoclonal antibody to CD99. For all cases, CD99 expression was scored on a four-tiered scale: negative, weak (1+), moderate (2+), or strong (3+). Two pathologists blinded to tumor diagnoses and type of immunostain evaluated each case independently. The interobserver correlation coefficient was calculated. Seventeen patients with AFX (16 males and one female; mean age = 79) and 26 patients with MFH (16 males and 10 females; mean age = 60) were included. AFX lesions were from the head and the face, mean size = 1.5 cm, and MFH lesions were from the head, the neck, the trunk, and the upper/lower extremities, mean size = 5.2 cm. The 17 cases of AFX demonstrated moderate or strong (2 to 3+) immunoreactivity with CD99, compared to nine of 26 (35%) MFH cases (chi-square = 18.38; p < 0.001; interobserver correlation coefficient = 0.83). Of these, 16 of 17 (94%) AFX cases stained diffusely with CD99, while only four of 26 (15%) MFH cases stained diffusely. Control slides were adequate. Our study demonstrated that CD99 can help distinguish AFX from MFH, in addition to other immunohistochemistry as well as clinical and histologic criteria.

Solitary sclerotic fibroma of skin: a possible link with pleomorphic fibroma with immunophenotypic expression for O13 (CD99) and CD34

BACKGROUND

Solitary sclerotic fibroma (SF) presents as a well circumscribed dermal nodule, composed of sparse spindle cells with alternating wavy collagen fibers arranged in a storiform pattern. The histogenesis and nature of this histologically distinct lesion are uncertain. Whether this peculiar tumor represents a true hamartoma or a degenerating end of various fibrous lesions such as pleomorphic fibroma (PF), dermatofibroma, or angiofibroma is still controversial. High proliferating index of spindle cells in SF argues against the possibility of being a degenerating end product of another lesion.

METHODS

We studied morphological features and immunoprofile of eight SFs, in comparison with four PFs, one collagenized dermatofibroma, two angiofibromas, and two periungual fibromas. Immunostains for CD34, CD31, O13 (CD99), Factor XIIIa, S-100, CD68 (KP-1), and MIB-1 were carried out using a labeled streptavidin-biotin method with DAKO-automated immunostainer. Paraffin blocks of two SFs were reprocessed for electron microscopic studies. Clinical data of all patients with SF were also reviewed.

RESULTS

Spindle cells and pleomorphic cells in SF and PF showed diffuse immunoreactivity for CD34 and O13 but were negative for CD31, S-100, and CD68. Spindle cells in one dermatofibroma and one angiofibroma were positive for Factor XIIIa. Proliferating index (MIB-1) was very low in all cases of SF, contradicting some previous reports.

CONCLUSIONS

SF is a fibrotic lesion with cells positive for CD34 and O13. It shares a common immunoprofile with PF but is distinct from dermatofibroma and other common spindle cell lesions of skin. O13 expression in SF has not been previously described.

Giant-cell fibroblastoma in a patient with a bone-marrow transplant

A case of an epigastric giant-cell fibroblastoma is reported in a 6-year-old girl who had undergone a bone-marrow transplant for severe combined immunodeficiency secondary to adenosine deaminase deficiency. A small subcutaneous nodule had been excised from the epigastrium at age 12 months.

Superficial collagenous fibroma: immunohistochemical, ultrastructural, and flow cytometric study of three cases, including one pemphigus vulgaris patient with a dermal mass

Collagenous fibroma (desmoplastic fibroblastoma) is an extremely rare benign soft tissue tumor of fibroblastic origin. The majority of reported cases have been located in the deep subcutis, fascia, aponeurosis, or skeletal muscle of the extremities, limb girdles, or head and neck regions. There has been no mention of underlying diseases in patients who developed this tumor. We here report an additional three cases of superficial collagenous fibroma, one of which was a dermal lesion occurring in the abdomen of a 26-year-old male patient with a 5-year history of pemphigus vulgaris prior to development of the tumor. To the best of our knowledge, an association between collagenous fibroma and pemphigus vulgaris has not previously been reported. The remaining two tumors were located in the superficial subcutaneous tissue of the infrascapular area and right foot, respectively. There was no tumor recurrence or metastasis during follow up of 18, 25, and 47 months, respectively. All three tumors were well-circumscribed and unencapsulated without infiltrating borders. Histologically, the common denominator of all three cases was paucicellular proliferation of spindle or stellate fibroblasts enmeshed within an extensively collagenous background. Immunohistochemically, there was diffuse strong staining for vimentin and intense focal reaction for smooth muscle actin in two tumors tested. Electron microscopy revealed features consistent with a fibroblastic or myofibroblastic lineage. Flow cytometry in two cases demonstrated a diploid DNA content with low S-phase fractions, which correlated with minimal MIB-1 nuclear labeling (less than 1%) and benign behavior of this entity.

Expression of CD34 in sclerotic ("plywood") fibromas

CD34 antigen is expressed in normal human skin on endothelium, in spindle cells located around adnexal structures, and in a subset of interstitial cells in the reticular dermis. CD34 expression has also been identified in a number of fibrohistiocytic neoplasms, such as dermatofibrosarcoma protuberans and solitary fibrous tumors of soft tissue. CD34 expression has not previously been described in sclerotic, or "plywood" fibromas. Here presented are three lesions from three patients, in which histologic examination revealed a well-circumscribed dermal nodule composed of spindled cells with focal nuclear pseudo-inclusions. There was extensive fibrosis with hypocellular, storiform areas, characteristic of sclerotic fibroma. The spindled cells strongly expressed CD34, but not factor XIIIa or markers of melanocytic, neural, or muscular differentiation. A diagnosis of Cowden syndrome was considered in one of the cases. These cases provide evidence that CD34 expression can occur in sclerotic fibromas, either solitary or associated with Cowden syndrome. When diagnosing a sclerotic fibroma, one should comment in the report regarding the possibility of Cowden syndrome.

Cortical benign fibromatous tumor (fibroma) of the kidney

Benign fibromatous tumor (BFT), also named 'fibroma', is a distinctive clinico-pathologic entity occurring in epididymis, spermatic cord, paratesticular structures, testis, renal peripelvis and rarely in renal parenchyma. We report the first case of a BFT (fibroma) located in the cortex of the kidney, and a critical review on the topic is provided. Tumor was found incidentally at autopsy as a small cortical nodule. With the increasing use of radiological imaging of the abdomen, it is likely that an increased number of incidental and asymptomatic benign renal tumors will be diagnosed. We underline that BFT (fibroma) should be considered in the preoperative differential diagnosis of renal cortical nodules.

Chemokine gene expression in human oral mucosa

In order to gain further understanding of the role of chemokines in healthy oral mucosa, we analyzed mRNA expression of the alpha (CXC)-family chemokines IL-8 and GROgamma as well as of the beta (CC)-family chemokines MIP-1alpha, MIP-1beta and MCP-1 in twenty young and healthy subjects with good oral hygiene. Twenty biopsies were taken from clinically healthy oral mucosa before surgical removal of impacted wisdom teeth. In addition, five biopsies from patients presenting with specific oral lesions were studied. RNA was purified, quantitated and utilized as substrate for competitive reverse transcription-polymerase chain reaction (RT-PCR). In healthy tissue, IL-8 and MCP-1 mRNA was constitutively expressed in all biopsies, whereas GROgamma, MIP-1alpha, and MIP-1beta were significantly lower. These findings suggest that IL8 and MCP-1 play a significant role in oral tissue homeostasis. The few samples from pathological conditions encourage exploring diseased tissue in more detail.

Solitary fibrous tumor of the paranasal sinuses

Although solitary fibrous tumors are well-recognized in the pleura, their occurrence in the paranasal sinuses is decidedly uncommon. We have encountered two cases of solitary fibrous tumors in the paranasal sinuses and report the clinicopathological findings including CD34 immunoreactivity. One tumor arose in a 55-year-old Japanese businessman and the other in a 53-year-old man who had been in the hospital for schizophrenia for 20 years. The tumors showed characteristic findings. Immunoperoxidase stains on paraffin sections showed staining of the cells for anti-vimentin, but there was no staining for anti-keratin, anti-S-100 protein, anti-desmin, anti-glial fibrillary acidic protein (GFAP), or anti-actin. Anti-CD34 monoclonal antibodies also reacted with these tumors, as those of the pleura generally do, and were found to be useful in diagnosing these tumors. CD34 immunoreactivity [8]. Fukunaga et al. [6] reported that CD34 immunoreactivity presented in a solitary fibrous tumor of the nasal cavity, but separate tumors of the paranasal sinuses have not been analyzed. We have recently encountered two cases of solitary fibrous tumors of the paranasal sinuses. In this report, the clinicopathological features of these tumors of and their CD34 immunoreactivity were analyzed.

Pacinian collagenoma

An unusual histological variant of collagenoma is described. A 36-year-old woman presented with a lump in the left hypothenar eminence. Histological examination revealed a well-delineated lesion composed of paucicellular collagen fibres arranged in concentric lamellations giving rise to an onion skin appearance. The overlying epidermis was thin and the lateral borders were demarcated by an epidermal collarette. Inflammation and xanthoma cells were absent and occasional capillaries were present. The lesion was positive for collagen stains, reticulin and CD34. This lesion represents an uncommon histological form of collagenoma or fibroma. It can be distinguished from histological look-alikes on the basis of the characteristic morphology and immunophenotype.

[CD-34 expression in elastofibroma. Clinicopathological, histochemical, and immunohistochemical study of four cases]

OBJECTIVE

To explore the immunohistochemistry of elastofibromas and to evaluate four elastic strain methods for the histological diagnosis of elastofibroma.

MATERIAL AND METHODS

Four elastofibromas were obtained from the surgical pathology files of the ABC Medical Center. All patients were women whose lesions were present in the subescapular region. Immunohistochemistry was performed for CD34, actin, desmin, vimentin, S-100 protein and bcl-2 and four elastic stain methods were evaluated (Verhoff, Gallego's, Reyes-Mota and Russel-Movat).

RESULTS

In the four cases there were numerous miofibroblasts (vimentin/actin/desmin positive). An unpreviously reported positive CD34 dendritic cells, were present diffusely in all four cases. Verhoff and Reyes-Mota stains remains the most useful methods to reveal the elastic fibers. Russel-Movat method may be use to contrast different connective tissue components.

CONCLUSION

The cell of elastofibromas were originally considered fibroblasts. The presence of actin/desmin/vimentin suggests that they are miofibroblasts. We describe for the first time, variable numbers of CD34(QBend/10) positive spindle shaped and dendritic cells in all elastofibromas. These cells may be a reactive population of cells of the "dendritic cell system". There was no immunoreactivity for bcl-2 in these cells.

[Giant cell fibroblastoma associated with Darier-Ferrand dermatofibrosarcoma in an adult]

INTRODUCTION

Giant cell fibroblastoma is a rare mesenchyma tumor of childhood having many similarities with dermatofibrosarcoma protuberans in adults.

OBSERVATION

We report the case of a 28-year-old woman presenting a subcutaneous inter-mammary mass associating both tumors. Immunohistochemistry showed an expression of CD 34 only by dermatofibrosarcoma protuberans cells.

DISCUSSION

It is important to stress: the rarity of this association, the difficulty to confirm the diagnosis and to establish the links between these two tumors: simple association (as in our case), transformation or recurrence of giant cell fibroblastoma in dermatofibrosarcoma protuberans.

Radical oncologic surgery affects the circulatory levels of interleukin 10

BACKGROUND AND OBJECTIVE

Interleukin 10 (IL-10) has been shown to be elevated in the plasma of cancer-bearing patients. The source of systemic IL-10 may be the tumor microenvironment. We therefore tried to evaluate if ablative surgery for gastrointestinal cancer could affect the levels of circulating IL-10.

METHODS

Plasma IL-10 concentration was measured in 45 patients with adenocarcinoma of the gastrointestinal tract. Forty healthy subjects, 15 women undergoing hysterectomy for uterine fibroma, and 15 patients undergoing palliative operation for pancreatic cancer were used as control groups. Plasma IL-10 was assessed 1 day before surgery (baseline) and 1, 4, and 8 days after operation.

RESULTS

The baseline concentration of IL-10 was significantly higher in cancer patients than in healthy subjects and in women with fibroma (8.6 ng/mL, 2.1 and 1.8 respectively; P = 0.015). After radical surgery, the IL-10 levels significantly dropped in cancer patients (from 8.6 ng/mL to 3.8; P = 0.024), whereas in subjects undergoing palliative operation, the concentration remained elevated (8.5 ng/mL baseline versus 7.9 on day + 1).

CONCLUSIONS

The origin of circulating IL-10 may be the tumor microenvironment.

[A case of ossifying fibromyxoid tumor]

Recently described entity: ossifying fibromyxoid tumour of soft parts is presented. Schwann cell nature of the proliferating cells was demonstrated by immunohistochemical means. This special kind of nerve sheath tumors is characterised by pathological differentiation of the cells, resulting bone and in some cases additional cartilage formation. As for biological behaviour: in spite of occasional histological evidences of malignancy, no distant metastases are to be expected. Local aggressivity and recurrences may occur, thus designation is preferable as semimalignant or according to more modern terms as low-grade malignant tumour.

Solitary fibrous tumor of the adrenal gland

Solitary fibrous tumors are rare neoplasms, most commonly involving the pleura, recently described in various other locations. We report a solitary fibrous tumor of the right adrenal gland in a 42-year-old woman, discovered incidentally during abdominopelvic ultrasonographic examination. Pathologic and immunohistologic features of the tumor were identical to those of other solitary fibrous tumors. Three-quarters of this unencapsulated infiltrating tumoral mass presented foci of hemorrhage and were made of small, round, epithelioid-like cells that expressed the CD34 antigen more weakly than do the typical spindle cells usually observed in solitary fibrous tumors. Despite hemorrhage and poor limitation, the tumor behaved in a innocuous manner; the mass remaining unchanged for more than 5 years before the patient agreed to surgical intervention, which was recommended because of a sudden enlargement of the mass.

Cutaneous adult myofibroma: a vascular neoplasm

Infantile myofibromatosis is a distinctive type of fibromatosis that usually develops during the immediate perinatal period. There are variants with solitary and multiple tumors. Lesions confined to the skin, soft tissue, and bone carry a good prognosis, showing spontaneous regression. The prognosis, however, is much less favorable when visceral lesions are present and the outcome may be fatal. Only recently it became obvious that there is an adult counterpart of infantile myofibromatosis, characterized by solitary lesions that have a predilection for involve the dermis and show no tendency to regression, although they have an entirely benign biological behavior. These lesions have been named cutaneous myofibroma or solitary myofibroma of adults. We have studied the clinical, histopathological and immunohistochemical characteristics of 53 examples of cutaneous adult myofibroma. In addition, 2 cases were examined ultrastructurally. The patients were mostly adults with ages ranging from 6-83 years. The lesions presented as solitary, usually painless nodules of variable duration on the skin, usually located on the extremities. Histopathologically, four patterns were identified: nodular or cellular type, multinodular or biphasic type, leiomyoma-like or fascicular type, and vascular type. A correlation between the histopathologic pattern and the lesional age was observed: vascular type of cutaneous adult myofibroma in early lesions, nodular and multinodular lesions in fully developed lesions, and leiomyoma-like or fascicular type in late lesions. Immunohistochemically, the spindle cells were desmin negative, but expressed immunoreactivity for vimentin, pan-smooth muscle actin, and alpha-smooth muscle actin. Ultrastructurally, neoplastic cells showed characteristics of undifferentiated mesenchymal cells with features of fibroblasts, myofibroblasts and pericytes. Primitive vascular formations were seen in the form of irregular clefts between adjoining cells. We conclude that cutaneous adult myofibroma is a little-known benign vascular neoplasm probably derived from myopericytes.

Ossifying fibromyxoid tumor of soft parts of the back

We report a first case of ossifying fibromyxoid tumor of soft parts of the back, a 10 x 9.5 x 6 cm well-circumscribed elevated subcutaneous tumor demarcated by an incomplete fibrous capsule with bone formation at its base. The tumor was composed of both myxomatous areas with spindle tumor cells and pseudoalveolar structures with oval tumor cells. The tumor cells had evenly sized, oval nuclei without atypia and slightly eosinophilic cytoplasm with intracellular vacuoles. Immunohistochemical studies revealed positivity for vimentin and focal positivity for S-100 protein. Ultrastructural examination revealed a few filopodia-like processes, discontinuous basal lamina and a few primitive cell junctions. Based on these immunohistochemical and ultrastructural results, this tumor may be related to Schwann's cells. There has been no recurrence 5 years after wide local excision.

Identification of antibodies against human papillomavirus type 16 E4 and E7 proteins in sera of patients with cervical neoplasias

Sera from 35 women (patients with various clinical diagnosis: cervical dysplasia, benign and malignant tumors of the uterine cervix) were tested by immunodot blot for the presence of antibodies to E4 and E7 HPV16 proteins. A number of 26 sera displayed positivities for at least one antibody type. The mean absorbance for anti-E antibody in positive cases was higher in cancer patients (15 from 16 sera) as compared with other diagnoses (2 from 5 in dysplasia or one from 4 in uterine fibroma). Interestingly, most sera were reactive for both proteins. The high prevalence rates and high absorbance values for HPV16 E7 antibodies in association with malignant transformation suggest that the detection of these antibodies may be a useful diagnostic aid for cervical cancer--associated HPV16.

Serum CA 125 concentrations in patients with benign ovarian tumours

Serum CA 125 concentrations have been measured in 115 patients with histologically confirmed nonmalignant pelvic disease, that is, serous cystadenoma (n = 56), mucinous cystadenoma (n = 14), fibroma (n = 33), thecoma (n = 8), and Brenner tumour (n = 4). Increased CA 125 concentrations (> 35 KU/L) were found in 14 patients, with a range of 46-891 KU/L, a mean of 205 KU/L, and a median of 97 KU/L. The highest values were found in patients with ascites. Serial measurements in one patient showed a fall in the 2 days immediately after surgery, over the next 3 days showing a two- to three-fold increase, followed by a slow return to normal over the next 7 weeks. Elevated CA 125 levels may not indicate ovarian malignancy and do not differentiate between benign and malignant pelvic masses.

CD-34 is expressed by a distinctive cell population in peripheral nerve, nerve sheath tumors, and related lesions

The pattern of CD-34 antigen (human progenitor cell antigen) immunoreactivity was studied within normal nerve, and a variety of nerve sheath and neuroectodermal tumors. Besides normal nerves, 111 soft tissue tumors were studied, including 17 neurofibromas, 10 neurilemomas, 12 malignant peripheral nerve sheath tumors, 1 melanocytic schwannoma, 21 fibroblastic lesions, 31 fibrohistiocytic lesions, seven neuroectodermal lesions, and 10 miscellaneous tumors. CD-34-positive dendritic cells were consistently identified within the endoneurium of normal nerve, all neurofibromas, dermatofibrosarcomas, and Antoni B (but not Antoni A) areas of neurilemomas. CD-34 was not expressed in the majority (eight of 10 cases) of malignant peripheral nerve sheath tumors. CD-34 was also lacking in all fibroblastic lesions (nodular fasciitis, fibromatosis, keloid, fibrosarcoma) and in neuroectodermal tumors that are not generally considered to show true nerve sheath differentiation (neurotropic melanoma, clear cell sarcoma, neuroepithelioma). We conclude that CD-34 (or a closely related epitope) defines a normally occurring nerve sheath cell that appears to be cytologically and immunophenotypically distinct from a fibroblast and conventional Schwann cell. The antigen can also be localized to benign nerve sheath tumors, but tends to be lost in malignant ones. The consistent presence of CD-34 within all 13 cases of dermatofibrosarcoma protuberans can be used as evidence in support of the view that these lesions are variants of nerve sheath tumors, and distinct from benign fibrous histiocytomas which consistently lack the antigen. Finally, expression of CD-34 by one of three giant cell fibroblastomas reinforces the close relationship between this tumor and dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans is a unique fibrohistiocytic tumour expressing CD34

Dermatofibrosarcoma protuberans (DFSP) is a slow growing, locally invasive tumour whose differentiation from other fibrohistiocytic tumours sometimes poses serious diagnostic problems. We investigated CD34 expression immunohistologically in various fibrohistiocytic tumours including dermatofibroma, DFSP, malignant fibrous histiocytoma (MFH), infantile myofibromatosis, fibrosarcoma, hypertrophic scar and keloid. Among these, DFSP was unique in that tumour cells themselves expressed CD34, whereas in other tumours. CD34 expression was observed only on vascular endothelial cells amongst the tumour cells. Until now, there have been no reports of useful immunohistological markers for DFSP. CD34 expression by the tumour cells can be an extremely useful marker in establishing a definitive diagnosis of DFSP.

Expression of HLA-A,B,C, beta 2-microglobulin (beta 2m), HLA-DR, -DP, -DQ and of HLA-D-associated invariant chain (Ii) in soft-tissue tumors

Non-neoplastic mesenchymal cells, along with 33 benign and 87 malignant soft-tissue tumors (STT) were examined for expression of HLA-A,B,C, beta 2-microglobulin (beta 2m), HLA-DR, -DP, and -DQ molecules and the HLA-D associated invariant chain (Ii). Serial frozen sections were immunostained using monoclonal antibodies (MAbs) to monomorphic framework determinants of HLA sublocus products, beta 2m and Ii, and to CD53, a recently defined broadly distributed pan-leucocyte molecule. Compared with the normal state, an induction/neo-expression of HLA-A,B,C/beta 2m was found in a considerable number of tumors of muscle, peripheral nerve, cartilage-forming, adipose, and vascular tissues. Conversely, some tumors of fibrous origin and of autonomic ganglia showed an abnormal abrogation/loss of HLA-A,B,C/beta 2m with respect to their cells of origin. Small, round tumor cells present in various types of STT exhibited a heterogenous pattern of expression of these molecules with a preponderance of HLA-A, B,C/beta 2m-negativity. HLA-D/Ii determinants were rarely detectable in STT. Besides their expression in some fibrohistiocytic tumors, they were only occasionally found in tumors of smooth-muscle, peripheral-nerve and vascular origin as well as in one clear-cell sarcoma. In all tumors but one, there was no microtopographic association between HLA-D/Ii-positive tumor cells and inflammatory cells. CD53 allowed discrimination between dendritic interstitial cells (DIC) and neoplastic cells and additionally revealed that, in contrast to other solid tumors, STT are generally characterized by an extreme scarcity of lymphohistiocytic infiltrates. Our data indicate that, aside from very rare exceptions, aberrant induction or abrogation of MHC molecules in STT occurs in the absence of lymphohistiocytic stromal infiltrates, suggesting that these alterations might not be a consequence of local cytokine effects.

Combined immunohistochemical study of tissue polypeptide antigen and cancer antigen 125 in human ovarian tumours

An indirect immunoperoxidase method was used to study the expression of tissue polypeptide antigen (TPA) and cancer antigen 125 (CA 125) in 47 benign and malignant ovarian tumours. Tissue polypeptide antigen and CA 125 antigen were expressed respectively in 22 (73%) and 16 (53%) of the 30 adenocarcinomas and in five (29%) and four (23%) of the 17 benign tumours. Co-expression of TPA and CA 125 antigen occurred in 12 (40%) malignant and four (23%) benign tumours. Ultrastructurally, TPA and CA 125 antigens were located at the cell surface and microvillous surfaces. Evaluation of combined TPA and CA 125 antigen results revealed a remarkable improvement in the positivity rate and a significant decrease (P less than 0.05) in the negativity rate of ovarian carcinomas as compared with the result of each one separately. These findings provide complementary evidence for the previous results on the plasma levels of TPA and CA 125 antigen and suggest that specific combinations of tumour markers may be more effective for the diagnosis and monitoring of ovarian carcinomas, than the use of any single marker.

Bovine serological response to a recombinant BPV-1 major capsid protein vaccine

Four of five groups of Holestine by Angus calves (5 calves/group) were immunized with different formulations of a recombinant BPV-1 DNA vaccine using a BPV-1 major capsid:B-galactosidase fusion protein as the immunogen. Group 5 was not vaccinated. Vaccinated calves received the vaccine on days 0 and 21 of the trial, and calves from all five groups were challenged intradermally with 10(10) BPV-1 particles at each of two different sites on day 56. All calves were bled on days 3, 24, 55, 77, and 104 of the trial, and the sera were tested for reactivity with intact and disrupted BPV-1 particles by ELISA. At the time of challenge with BPV-1 virions (day 56), 19 of 20 vaccinated calves were seropositive for disrupted BPV-1 particles; sera from 3 of 20 calves reacted with intact BPV-1 virions. By day 77, 11 of 19 vaccinated calves had developed antibody titers to intact BPV-1 virions; only 1 calf in group 5 developed antibodies (transiently) against BPV-1 capsid epitopes. After challenge, 24 of 25 calves from the five groups developed intradermal fibromas, the biological end point of this study. Fibromas appeared to increase in size in group 5 (unvaccinated, inoculated controls), whereas most tumors from the four vaccinated groups (1-4) stabilized or decreased in size. Although the calves developed fibromas, 90% of calves (in groups 1-4) developed antibodies against disrupted BPV-1 capsid proteins whereas 58% developed antibodies that reacted with intact virions. The immunologic response of vaccinated calves to intact and disrupted BPV-1 particles appeared to be determined in large part by the various formulations of the vaccine, particularly the adjuvant.

Infantile digital fibromatosis. Immunohistochemical and ultrastructural observations of cytoplasmic inclusions

Using antibodies against actin, tubulin, and intermediate filaments immunohistochemical studies were performed on a nodule from an 8-month-old girl with infantile digital fibromatosis. None of the antibodies significantly stained the cytoplasmic inclusion bodies, which were a distinct morphologic feature of this fibromatosis. This result is in contrast to a previous report that stated that the inclusions were composed chiefly of actin filaments. In ultrastructural term, the tumor cells were morphologically consistent with cells in myofibroblasts. The inclusions consisted of packed fibrillar and granular substances. Cultured cells containing inclusions identical to those seen in the original tumor mimicked a growth pattern in vivo. Scanning electron microscopy showed that cultured cells had thin foot processes containing many microspikes. Detergent-treated preparations examined by transmission electron microscopy displayed a microtrabecular meshwork characterized by three, major cytoskeletal domains with many actin cables. Cultured cells showed a normal karyotype.

Papillomavirus genomes in experimentally induced fibromas in white-tailed deer

Cutaneous fibromas of white-tailed deer were transmitted successfully to 5 young deer. Serial biopsy specimens of the induced lesions were analyzed for white-tailed deer papillomavirus, using Southern blot hybridization. Viral genomes were found in all specimens taken 1 to 7 weeks after inoculation and, in some cases, from specimens of the inoculation site obtained later. Viral DNA was found before histologic evidence of fibroblast proliferation and persisted in low copy number, compared with viral DNA of naturally developing fibromas.

"Clear cell" atypical fibroxanthoma

An 87-year-old man with extensive solar damage presented with a 2-month history of a dome-shaped, crusted lesion on the dorsum of the left hand. Microscopically, the tumor consisted of fascicles of spindle cells with bizarre nuclei and clear, vacuolated cytoplasm. Histochemical, immunohistochemical, and ultrastructural features supported the diagnosis of atypical fibroxanthoma. There was no evidence of metastatic disease. The lesion was completely excised, and there has been no recurrence in 3 months of observation. This unusual "clear cell" variant of atypical fibroxanthoma must be distinguished from other clear cell tumors, such as metastatic renal cell carcinoma, clear cell eccrine carcinoma, and clear cell sarcoma (malignant melanoma) of soft parts. Although atypical fibroxanthoma is usually cured by complete surgical excision, metastases have been reported.

Atypical fibroxanthoma of the skin: a clinicopathological and immunohistochemical study and a discussion of its histogenesis

The morphological and immunohistochemical characteristics of 37 atypical fibroxanthomas of the skin were examined. Twenty-four tumours were nodular ulcerative lesions on the head and face of patients with a median age of 75 years, whereas 13 tumours occurred on the trunk and limbs of patients with a median age of 48 years. Both pleomorphic polygonal and giant cells as well as the spindle cell component of the tumours stained for the histiocytic markers alpha 1-antichymotrypsin, alpha 1-antitrypsin, lysozyme and, less frequently, for ferritin. Leu M1 antigen and peanut agglutinin receptors were not demonstrable in tumour cells. This antigenic profile was contrasted with the findings in six cases of dermatofibroma which were largely not reactive with the antisera used. The immunohistochemical findings in atypical fibroxanthomas suggest that they represent a homogeneous group of tumours which are related to tissue histiocytes. These results are discussed in the context of the published findings in other so-called fibrohistiocytic tumours including dermatofibrosarcoma protuberans and malignant fibrous histiocytoma. The diagnoses in three cases coded as atypical fibroxanthomas were revised on the basis of their showing a different immunohistochemical profile.

Pseudosarcomatous fibromyxoid tumor of the urinary bladder

The light-microscopic, immunohistochemical, and ultrastructural features of two examples of a pseudosarcomatous fibromyxoid tumor of the urinary bladder are reported. Both patients were women, 56 and 52 years old. Gross hematuria was the chief complaint and occurred for two days and two weeks, respectively, before presentation. Cystoscopy revealed a 2 X 1 X 1 cm mass located at the dome in case 1 and a 4 X 3 X 3 cm mass at the left posterior lateral wall in case 2. Microscopically, the lesions were composed of spindle, plump, or stellated fibroblast-like cells embedded in myxoid stroma with little collagen; mitotic figures were about 2 per 10 high-power fields, and both cases showed encroachment of the superficial muscle bundles. Because of bizarre spindle cell proliferation, occasional mitoses, and invasion to the underlying muscle, these lesions were initially diagnosed as embryonal rhabdomyosarcoma. However, follow-up examination disclosed the benign nature of these lesions. There was no previous instrumentation or surgery on the genitourinary tract. Immunohistochemical and ultrastructural studies revealed the fibroblastic-myofibroblastic nature of these lesions. These cases illustrate that clinicopathologic correlation is essential to define certain pseudosarcomatous lesions.

Biological characterization of human bone tumors. VIII. Expression of HLA-DR antigens in bone tumors and tumor-like lesions

A total of 45 cases of bone tumors and tumor-like lesions were studied in order to determine the expression of an HLA-DR antigen by the monoclonal antibody 910-D-7, and its possible correlation with histology, using the indirect immunoperoxidase method on frozen sections. The pattern of antigen expression was nearly constant for the individual cell types, though varying in intensity, and did not depend on the biological behavior of the respective lesions. No clear correlation could be established between antigen expression and cell maturation. Although the biological significance of antigen expression in these tumors is not yet understood, it is clear that here, too, the mere presence of an HLA-DR antigen cannot be interpreted as a sign of malignant transformation.

Inflammatory pseudotumour of the liver

Five cases of inflammatory pseudotumour of the liver are reported and compared with seven individual previously published case reports. Clinical presentation was variable but often comprised low grade intermittent fever, vague abdominal symptoms, and a history of weight loss. Leucocytosis, raised erythrocyte sedimentation rate, and polyclonal hyperglobulinaemia were also sometimes detected. All five cases in the present series were considered to be clinically malignant; and in two the histological diagnosis was also that of malignancy. The lesion is clearly inflammatory and reactive, but the aetiology remains unknown.

Characterization of breast carcinomas by two monoclonal antibodies distinguishing myoepithelial from luminal epithelial cells

Two monoclonal antibodies, KA 1 and KA 4, raised against human epidermis, were biochemically and immunologically characterized and were shown to react with specific cytokeratin polypeptides. On frozen sections of human mammary gland, these antibodies distinguish between myoepithelial and luminal epithelial cells. We present evidence that in these cells KA 1 antibody recognized cytokeratin 5 and KA 4 antibody cytokeratin 19. In normal mammary tissue, KA 4 antibody invariably reacted with the epithelial cells lining the lumina of acini, ductules, ducts, and sinus. In contrast, KA 1 antibody decorated only the myoepithelial and basal epithelial cells of acini, ducts, and sinus. In ductules, however, KA 1 also stained the luminal cells. All 73 invasive lobular and ductal carcinomas studied reacted with KA 4 antibody; five of these were also positive, apparently in the same tumor cells, with KA 1. The tumor cells of in situ carcinomas were also stained in a homogeneous pattern with KA 4 antibody; KA 1 antibody reacted only with the surrounding myoepithelium. In epithelial hyperplasias, the proliferating cells were decorated by KA 1 and KA 4 antibodies in a heterogeneous pattern. Other antibodies were used for comparison. The results are discussed with respect to epithelial differentiation and pathogenesis and to the application of such antibodies for immunohistodiagnosis of mammary lesions.

Inflammatory lymphadenoid reactions with dermatofibroma/histiocytoma

Lymphoid nodules were found associated with 44 of 1,506 dermatofibroma/histiocytoma tumors of the skin. The lymphoid nodules were usually in the adjacent fat. Germinal center formation occurred, and perinodular and perivascular plasmacytosis was frequently associated.

Inflammatory fibroid polyp of the stomach

Fourteen cases of inflammatory fibroid polyp of the stomach were studied in terms of immunohistochemistry and ultrastructure. They occurred as polypoid lesions in the antrum, except for two found in the body of the stomach. Out of the 14 cases, two were found to be multiple and the remainder solitary. In all but one lesion, the mucosal layer was involved and six lesions were entirely localized within the mucosal layer, suggesting that inflammatory fibroid polyps of the stomach originate in the mucosal layer. Neither S100 protein, factor VIII-related antigen, alpha 1-antitrypsin nor lysozymes were found in the cytoplasm of the proliferating cells. The ultrastructures of the proliferating cells were fibroblastic rather than neurogenic, angiogenic, or myofibroblastic. These findings suggest that the cells are fibroblasts, though the possibility that they are facultative fibroblasts remains. An interesting observation made with electron microscope was the infection of micro-organisms similar to mycoplasma. This seems to deserve further investigation as a possible etiologic factor of the disease.

[Unilateral pseudotumor of the orbit--an autoimmune disease?]

An eleven-year-old boy with congenital paresis of the left superior rectus eye muscle developed symptoms of acute left orbital expansion: pain, ptosis, redness, extraocular muscle dysfunction. Computer assisted tomography of the orbit showed typical signs of inflammatory orbital pseudotumor and immunological screening cryoglobulinemia. Short-term treatment with prednisone (2 mg/kg bodyweight/day) rapidly improved symptoms. However several relapses occurred following discontinuation of therapy. Therefore a long-term treatment with corticosteroids was instituted. The simultaneous development of inflammatory orbital pseudotumor and cryoglobulinemia support the hypothesis that orbital pseudotumor is an autoimmune disease. The meaning of the congenital superior rectus muscle paresis in this case for the development of the inflammatory process remains uncertain.

Cellular differentiation in ovarian sex-cord-stromal and germ-cell tumors studied with antibodies to intermediate-filament proteins

Seventy ovarian sex-cord-stromal and germ-cell tumors were immunohistochemically studied for the presence of intermediate-filament proteins of different types used as markers for cellular differentiation. Cells of ovarian granulosa-cell tumors constantly expressed vimentin and appeared to lack cytokeratin. Two tumors previously classified as granulosa-cell tumors were reclassified as poorly differentiated "common" epithelial tumors based on their cytokeratin positivity, vimentin negativity, and morphologic features. Dysgerminomas and Leydig-cell tumors showed only vimentin positivity. Tubular structures in androblastomas, which are considered to represent Sertoli-cell differentiation, were cytokeratin positive, and thus differed from the majority of normal Sertoli cells that are known to express vimentin and not cytokeratin. Embryonal carcinomas, choriocarcinomas, and endodermal sinus tumors showed cytokeratin positivity in the neoplastic cells whereas vimentin was observed in the stromal cells. In immature teratomas, epithelial differentiation was demonstrated with cytokeratin antibodies, and neural and glial differentiation was also frequently demonstrated by immunostaining with antibodies to neurofilaments and glial fibrillary acidic protein. The results show that antibodies to intermediate filaments can be used in the differential diagnosis between ovarian epithelial and nonepithelial tumors, and they provide a very accurate additional method to characterize the cellular differentiation of ovarian neoplasms.

Subcutaneous fibromatosis associated with an acquired immune deficiency syndrome in pig-tailed macaques

A spontaneous multifocal subcutaneous fibromatosis is described in 6 pig-tailed macaques (Macaca nemestrina) with simian acquired immune deficiency syndrome (simian AIDS). The lesions consisted of a proliferation of vascular fibrous tissue that was infiltrated by lymphocytes and plasma cells. One animal also had retroperitoneal fibromatosis, which has also been found in this colony of pig-tailed macaques. Progressive weight loss, diarrhea, lymphadenopathy, and neutropenia were seen. Peripheral lymph nodes were hyperplastic, and there was splenomegaly. Aggregates of lymphocytes were present in the bone marrow, kidneys, liver, and lungs. Type D retrovirus particles were found in three nodules by electron microscopy; intracytoplasmic type A and budding particles were identified in fibroblasts. In a setting of acquired immunodeficiency, these subcutaneous tumors in pig-tailed macaques present a striking analogy to Kaposi's sarcoma in human AIDS.

Human papilloma virus (HPV) antigens and local immunologic reactivity in oral squamous cell tumors and hyperplasias

A series of 191 oral mucosal tumors including those with suspected HPV (Human Papilloma Virus) etiology; squamous cell papilloma (SQP), condyloma acuminatum (CA), focal epithelial hyperplasia (FEH), as well as those regarded as unrelated to HPV; fibrous hyperplasia (FH), papillary hyperplasia (PH), and true fibroma (TF), were analyzed for HPV structural proteins (by indirect immunoperoxidase IP-PAP technique), for the presence of epithelial dysplasia, and for the cellular composition (B and T lymphocytes, mononuclear phagocytes, (MPS cells] of their local inflammatory cell infiltrates using ANAE-(acid alpha-naphthyl acetate esterase) stain. HPV structural proteins were disclosed in 85% of FEH, in 75% of CA, and in 41% of SQP. These three lesions significantly differed from PH and FH with regard to the intensity and cellular composition of the local infiltrates, being most intense and B cell predominated in the latter two. Mild dysplasia was found in 20% of both CA and SQP lesions, the former also showing moderate dysplasia in 12% of cases. The HPV antigen positivity was negatively correlated with dysplasia in CA and SQP, the intensity of the infiltrate showing positive association with dysplasia. The results are discussed in terms of HPV etiology of CA, SQP and FEH, of the host immunologic reactivity against these lesions, as well as of the possible role of HPV in human squamous cell carcinogenesis.

Immunohistologic study of cellular populations of histiocytofibromas ("dermatofibromas")

Histiocytofibromas (HF) are benign tumours of the skin, the cellular composition of which is not yet known with certainty. The immunohistologic characteristics of 5 lesions were studied by using monoclonal antibodies and an indirect immunofluorescence method. All tumours were found to contain HLA-DR(+) cells, and, to a minor degree, OKM1(+) cells. OKT6(+) cells were present in the epidermis overlying the tumours; however in the HF themselves, no OKT6(+) cells were found. The presence of HLA-DR(+) and OKM1(+) cells demonstrates that HF contain cells bearing antigenic characteristics of histiocytes but not of Langerhans' cells, and we feel that the term "histiocytofibroma" is a more accurate designation for these lesions than "dermatofibroma".