A comparative analysis of immunohistochemistry and fluorescent in situ hybridization assay to detect anaplastic lymphoma kinase status in lung adenocarcinoma cases: A search for a testing algorithm

INTRODUCTION

Testing for echinoderm microtubule-associated protein-like 4 (EML4) anaplastic lymphoma kinase (ALK) translocation by fluorescence in situ hybridization (FISH) is well established whereas the Food and Drug Administration (FDA) ALK immunohistochemical (IHC) test is relatively new.

AIMS AND OBJECTIVE

The aim of this study is to compare FDA-approved ALK IHC test (D5F3 clone) with the standard ALK FISH test.

MATERIALS AND METHODS

A validation and a test arm with 100 and 200 cases of Formalin-Fixed, Paraffin-embedded blocks of lung adenocarcinoma, respectively, comprised the material. All cases had ALK IHC test on automated Ventana Benchmark XT IHC slide stainer using anti-ALK D5F3 rabbit monoclonal primary antibody; when positive tumor cells (any percentage) showed strong granular cytoplasmic staining. For the FISH test, Vysis ALK Dual Color Break Apart Rearrangement Probe (Abbott Molecular Inc.,) was used to detect ALK gene 2p23 rearrangements; when positive the red and green signals were split two signal diameter apart and/or isolated 3'red signal were detected in more than 15% tumor cells. The ALK FISH results were available in all 100 validation cases and 64-test arm cases which formed the basis of this analysis.

RESULTS

The ALK IHC test was positive in 16% cases; four discordant cases were ALK IHC positive but ALK FISH negative, but no case was ALK IHC negative and ALK FISH positive. There was 100% sensitivity, 90.5% specificity, and 93.75% accuracy.

CONCLUSION

A negative ALK IHC result obviates the need for a FISH test barring those with a strong clinical profile, and a positive ALK IHC result is sufficient basis for the initiation of treatment.

A clinicopathologic analysis of 88 lung resections of suspected metastatic carcinomas with proven primaries

BACKGROUND

The lung is the most common site for metastatic carcinomas. Very few studies have comprehensively analyzed all pulmonary resections for metastatic carcinomas.

AIMS AND OBJECTIVES

To analyze all lung resections for suspected metastatic carcinomas accrued over 10 years to evaluate: (i). The most frequent primary site,(ii). The interval between primary tumor diagnosis and lung metastases, and (iii). The proportion of inadvertently resected benign lesions, clinicoradiologically mistaken for metastatic deposits.

MATERIALS AND METHODS

Between 2002 and 2011, 88 pulmonary metastasectomies were done for suspected metastatic carcinomas, which form the basis of this study.

RESULTS

In 81 of 88 cases (92%) the diagnosis of metastatic carcinoma was histologically confirmed, whereas 7 cases (8%) were non-neoplastic. The mean interval between primary tumor and metastases was 2.5 years. The primary sites were colorectum (30; 37%), kidney and breast (14; 17.3% each), cervix (9; 10%), salivary gland carcinoma (3), thyroid carcinoma (2), squamous carcinoma (2, one each of mandible and larynx), papillary urothelial carcinoma (2), hepatocellular carcinoma (1), endometrioid adenocarcinoma (1), carcinosarcoma of endometrium (1), adrenocortical carcinoma (1), and neuroendocrine carcinoma (1). The 7 non-neoplastic lesions (8%) histologically revealed tuberculosis (4), bronchopneumonia (2), and aspergillosis (1).

CONCLUSIONS

Almost three fourths (71.6%) of the metastatic pulmonary resections comprised primaries from colorectum, breast and kidney. The interval between primary tumor and metastases ranged from zero months to 10 years (mean 2.5 years). Tuberculosis was the most common histologic diagnosis among the 8% of the non-neoplastic lesions, which were mistaken for metastatic carcinoma on clinical evaluation.

A year of anaplastic large cell kinase testing for lung carcinoma: pathological and technical perspectives

BACKGROUND

An in-frame fusion protein between echinoderm microtubule-associated protein-like 4 (EML4) and anaplastic large cell kinase (ALK) genes is seen in some non-small cell lung cancer (NSCLC). EML4-ALK demonstrates constitutive kinase activity. These ALK-positive lung carcinomas have been shown to respond to ALK kinase inhibitors. ALK gene rearrangement is commonly detected using fluorescent in situ hybridization (FISH).

AIMS

To study the pathological features of ALK positive and negative NSCLC and evaluate the causes of uninterpretable FISH results.

MATERIALS AND METHODS

This is a retrospective, observational study. The molecular pathology records of patients on whom test for ALK had been performed in a period of 1 year (February 2012 to February 2013) were accessioned. A total 224 cases were identified. Histological features were reviewed. The in situ hybridization was performed using Vysis ALK Dual Color Break Apart Rearrangement Probe (Abbott Molecular Inc.). Signal interpretation under the fluorescent microscope was performed in accordance with College of American Pathologists guidelines.

RESULTS

Five patients showed ALK gene rearrangement, 182 were negative and 37 cases were uninterpretable. Five patients with ALK gene rearrangement had a mean age of 48 years and the male to female ratio was 2:3. In the ALK negative cases, the mean age was 54 years and male to female ratio was 3.2:1. Histologically, amongst the rearranged cases, three showed solid pattern, one showed acinar and one showed acinar with signet ring cells on histology.

CONCLUSION

The percentage of ALK gene rearrangement was 2.7% (excluding the uninterpretable cases). These ALK positive patients were relatively younger than ALK negative patients. Solid pattern on histology was associated with ALK positivity. In a quarter of the uninterpretable results, the material submitted was fixed and processed outside.

Pulmonary adenofibroma: clinicopathological study of 3 cases of a rare benign lung lesion and review of the literature

Pulmonary adenofibroma is a rare benign biphasic tumor of the lung composed of epithelial and stromal components. We report 3 cases of this unusual lesion of lung in a male (25 years old) and 2 female (40 and 55 years old) patients. Breathlessness on exertion and mild left-sided chest pain of 1 month's duration were the main concerns in 2 patients, whereas the third had cough and hemoptysis for 3 months. Chest radiograph and computed tomography scan revealed a well-circumscribed, subpleural homogenous mass in left lower chest fields in 2 cases and solid-cystic lesion in left upper lobe in the third patient. All 3 patients underwent lobectomy, following biopsy in 2 cases. Histology revealed a well-circumscribed lesion composed of complex glandlike spaces lined by cuboidal to columnar epithelium surrounded by a hyalinized spindle-cell fibroblastic proliferation reminiscent of adenofibroma of the female genital tract or fibroadenoma of the breast. Immunohistochemical examination supported the diagnosis of a benign pulmonary adenofibroma. All 3 patients were are alive and doing well with no evidence of recurrent or metastatic disease. Diagnosis on biopsy can be challenging and may be misinterpreted as well-differentiated adenocarcinoma with extensive fibrosis or low-grade sarcoma. Frozen-section consultation will be a valuable adjunct in planning for limited lung resection of this benign lung lesion. Although we described 3 cases of pulmonary adenofibroma, still this is the largest published series of this rare entity till date. The possible histogenesis and various differential diagnoses are discussed along with literature review.

Toward an evidence-based proposal for the best minimal immunohistochemical panel to infer lung carcinoma in metastatic supraclavicular lymph node

Carcinomas from either pulmonary or extrapulmonary sites can metastatise to supraclavicular lymph nodes. Immunohistochemistry (IHC) is invaluable to comment on the possible primary site. However, the optimal number of antibodies to be tested is debatable. Seven antibodies were tested on 135 metastatic supraclavicular lymph node biopsies to propose a "best minimal" IHC panel to infer lung carcinoma, incorporating the principles of "evidence-based medicine." The 135 cases were divided into the following: category I (110 cases), wherein the primary was in the lung based on histologic analysis (Ia, n = 14 [12.7%]), cytologic analysis (Ib, n = 43 [39.1%]), or strong clinicoradiologic evidence (Ic, n = 53 [48.2%]), and category II (25 cases) with a histologically proven extrapulmonary primary site. Categories Ia and Ib were together designated as the "control group," and category Ic was designated as the "test group." The antibodies tested were cytokeratin (CK 7, CK20), epithelial membrane antigen, carcinoembryonic antigen, thyroid transcription factor-1 (TTF-1), surfactant protein B (SPB), and vimentin. Results of both individual and panels of antibodies were statistically evaluated. The sensitivity and specificity of single antibodies for inferring a lung primary was as follows: CK7 (90%/56%), CK20 (98%/40%), epithelial membrane antigen (90.9%/4%), carcinoembryonic antigen (80.9%/36%), TTF-1 (62.7%/100%), SPB (65.6%/100%), and vimentin (60.9%/60%). The highest sensitivity (85%) and specificity (100%) were seen with a 4-antibody panel: CK7, CK20, TTF-1, and SPB. This panel revealed the highest binomial probability (.8), for diagnosing lung cancer. The results were validated using a "split sample method," and a high concordance was noted between the control and test groups. To conclude, such evidence-based validated studies analyzing IHC results would be invaluable to guide the practice of surgical pathology in the future.

Critical histopathological analysis of 25 dedifferentiated liposarcomas, including uncommon variants, reviewed at a Tertiary Cancer Referral Center

BACKGROUND

De-differentiated liposarcomas (DDLSs) are uncommon tumors with a wide histopathological spectrum.

MATERIALS AND METHODS

Over an 8-year period (2003-2011), 25 DDLSs, after review, were critically analyzed for histopathological features.

RESULTS

Twenty-five tumors, in 14 men and 11 women (M: F = 1.2:1), with age range of 22-88 years (mean, 53.9), occurred in retroperitoneum (14) (56%), thigh (3) (12%), paratesticular region (3) (12%), chest wall (2) (8%), leg (1) (4%), shoulder (1) (4%), and groin (1) (4%). Tumor size (21 tumors) varied from 7.5 to 25 cm (mean, 17.5). Histopathologically, DD component was high grade in 19 (76%) and low grade in 6 (24%) tumors. Whereas the most common WD component was adipocytic type; the most common DD component was pleomorphic sarcomatous (13) (52%), followed by myxofibrosarcomatous (MFS)-type (6) (24%). Low-grade DD components included MFS (2), fibrosarcoma (2), myogenic/myofibroblastic type (1), and IMFT-type (1). Three tumors displayed meningothelial-like whorls and metaplastic bone formation. Heterologous elements, noted in 11 (44%) tumors, included bone (8) and rhabdomyoblastic differentiation (2). Two tumors displayed homologous differentiation, reinforced with MDM2 staining. S100-P was diffusely positive in WD components (5/7) and focally in DD components (2/9). All patients were treated with surgery, including 10, who underwent adjuvant radiotherapy. Outcomes (16 patients, 64%), over 1-48 months included 10 patients free of disease, 4 died of disease, and 2 patients alive with disease.

CONCLUSIONS

This study forms the largest documentation of DDLSs, including its wide histopathological spectrum, from our country. Rare cases overlap with pleomorphic liposarcoma. S100-P and MDM2 are useful in substantiating adipocytic differentiation, especially in selected cases. Analysis of adequate tumor sections is vital for correct identification of a DDLS. Surgical excision with adjuvant RT forms optimal treatment.

Osteosarcoma of the femur mimicking Ewing sarcoma/primitive neuroectodermal tumour on biopsy and metastatic carcinoma on resection

Osteosarcoma (OS) is known to have several morphological appearances, small cell osteosarcoma and epithelioid osteosarcoma being two well recognized patterns. The former can be mistaken for a Ewing sarcoma/primitive neuroectodermal tumour (ES/PNET), whereas the latter mimics metastatic carcinoma. Herein we present an osteosarcoma in a 17-year-old girl that was diagnosed as an ES/PNET on biopsy; however, the resected specimen revealed a very unusual morphology mimicking a metastatic carcinoma with a sex cord stromal tumour-like pattern.

A clinico-morphological study of 95 cases of sarcomas with metastases to the lungs

BACKGROUND

Metastasis of soft tissue sarcoma most commonly occurs to the lungs. There are very few studies on histology of pulmonary metastatectomy and hardly any wherein the histology of the primary tumor has been compared with the metastasis.

AIMS AND OBJECTIVES

To review histologically all metastatic sarcomas to lung and compare with the primary where available.

MATERIALS AND METHODS

Ninety-five patients with pulmonary metastases from sarcoma were analyzed histologically for type of sarcoma, chemotherapy-related changes, and changes in adjacent lung. Various clinical parameters like laterality, multiplicity, and interval between primary and metastasis were also studied.

RESULTS

Osteosarcoma constituted half of the metastatic sarcomas (48 cases, 50.5%) followed by synovial sarcoma (16 cases, 16.8%) and high grade spindle cell sarcoma-NOS (10 cases, 10.5%). The histology of primary and the metastases was similar in 60% of cases of osteosarcoma.

CONCLUSIONS

Osteosarcoma is the commonest metastatic sarcoma to the lung. There is often a change to fibroblastic histology in patients of conventional osteosarcoma treated with chemotherapy.

Phosphaturic mesenchymal tumor with chondromyxoid fibroma-like feature: an unusual morphological appearance

Phosphaturic mesenchymal tumor (PMT) is a rare and distinctive tumor almost always associated with oncogenic osteomalacia. This tumor is often misdiagnosed due to its widely varied histomorphological spectrum. More recently the term PMT or its variants has been used whatever the histomorphological features. Herein, we present a case of a 32-year-old woman who presented with a 2-year history of oncogenic osteomalacia. The clinical examination failed to detect any tumor. The F-18 FDG PET scan and subsequent MRI revealed a tumor in the soft tissues of the right popliteal fossa. The histological features resembled a chondromyxoid fibroma (CMF), a feature documented only in two cases so far.

Primary leiomyosarcoma of bone--a clinicopathologic study of 8 uncommon cases with immunohistochemical analysis and clinical outcomes

Primary leiomyosarcoma of bone is a rare and a diagnostically challenging tumor entity. Over a 7-year period, we identified 8 such cases that fulfilled the diagnostic criteria in 6 men and 2 women, with age ranging from 25 to 59 years (mean, 42.7 years). All cases were noted in the lower limbs, including femur and tibia as the commonly involved bones in 4 and 3 cases, respectively. On radiography, the most consistent feature was a solitary osteolytic lesion with cortical destruction, unassociated with matrix formation. On histopathology, all cases showed spindly sarcomatous cells, mostly arranged in fascicles and whorls. Of 8 cases, 6 (75%) were of high grade. Prominent vasculature was noted in 5 cases. Two cases displayed focal mineralization, including calcification and heterotropic woven bone formation in 1 case each, but lacked malignant osteoid or chondroid matrix. One case showed osteoclast-like giant cells. On immunohistochemistry, smooth muscle actin was diffusely positive in all cases (100%), desmin was positive in 6 (75%) of 8 cases, and h-caldesmon was positive in 5 (83.3%) of 6 cases. Five cases underwent surgery, including 3 amputations and 2 wide excisions. One case underwent chemotherapy. On follow-up, 5 cases developed metastasis, including 1 case with another, who died within 17 and 5 months. Leiomyosarcoma of bone is uncommon and diagnostically challenging. An index of suspicion is necessary for this diagnosis, especially in cases of lytic, destructive bone lesions, unassociated with matrix production, that show spindly sarcomatous cells on histopathology. Immunohistochemical analysis, including an optimum panel formed by smooth muscle actin (diffuse positivity), desmin, and h-caldesmon, is necessary for substantiating this diagnosis. Surgery forms the treatment mainstay. The prognosis appears to be dismal.

ALK+ anaplastic large cell lymphoma with cohesive, perivascular arrangements on cytology, mimicking a soft tissue sarcoma: a report of 2 cases

BACKGROUND

An accurate recognition of a lymphoma at an extranodal site is essential to avoid unnecessary excisions. Fine needle aspiration cytology (FNAC) has been recognized as a useful tool in the primary diagnosis of soft tissue tumors. An anaplastic large cell lymphoma (ALCL), occurring in soft tissues, poses a diagnostic challenge. We present the cytomorphology of 2 cases of anaplastic lymphoma kinase (ALK)+ ALCL that displayed a perivascular arrangement, thereby mimicking a sarcoma.

CASES

The patients were aged 16 and 9 years. While the former presented with multiple nodular soft tissue and bony lesions over the body, the latter complained of an axillary lump. FNAC smears in both cases showed pleomorphic cells, arranged in loosely cohesive groups around blood vessels and scattered singly, with prominent nucleoli and abundant, finely vacuolated cytoplasm. Interspersed were a few cells with embryoid nuclei. Differential diagnoses included a rhabdomyosarcoma and a lymphoma. On biopsy and immunohistochemistry, tumor cells were positive for vimentin, LCA, EMA, CD30 and ALK.

CONCLUSION

ALCL should be considered in the differential diagnosis of pediatric soft tissue tumors, especially in cases with multifocal involvement. The presence of cohesive, perivascular arrangements on FNAC should not detract a cytologist for keeping this possibility in mind. Further, a careful search for the typical "hallmark" cells should be made.

Extracorporeal irradiated tumor bone: A reconstruction option in diaphyseal Ewing's sarcomas

BACKGROUND

Limb salvage in extremity tumors is now established as an oncologically safe option without compromising long-term survival. En bloc resection followed by extracorporeal radiation and reimplantation is a biological reconstruction option in diaphyseal Ewing's sarcomas. We analyzed the results of 12 cases of diaphyseal Ewing's sarcomas treated using this modality.

MATERIALS AND METHODS

Between March 2006 and March 2008, 12 patients with Ewing's sarcoma underwent enbloc resection and reconstruction, with reimplantation of the sterilized tumor bone, after extracorporeal irradiation. There were eight males and four females, with a mean age of 14 years (range 2 to 22 years). The femur was the most common bone involved (n=8) followed by the tibia and the humerus (two cases each). All these patients were non-metastatic at presentation and received chemotherapy as per the existing hospital protocol. The mean length of the bone resected was 20 cm (range 11 to 25 cm). The specimen was irradiated with 50 Gy prior to reimplantation and stabilized with the host bone, using suitable internal fixation. Standard biplanar radiographs were assessed for evidence of union on the follow-up visits. The functional status was assessed using the Musculoskeletal Tumor Society Scoring system at the time of the last follow up. The mean follow up duration was 29 months (range 12 to 57 months).

RESULTS

Two patients (17%) had early infection with graft removal, hence are excluded from any analysis of union, however they are included when analysing complications such as infection. Rest 10 cases were analyzed for bony union at the osteotomy sites. Sixteen (84%) of the 19 osteotomy sites united primarily, without any intervention. Implant failure and non-union was seen at three diaphyseal osteotomy sites. The average time for union of all osteotomy sites was 7.2 months (range 3 to 13 months).The average time for union of the metaphyseal osteotomy sites was 5.9 months (range 3 to 12 months) and of diaphyseal osteotomy sites was 8.3 months (range 4 to 13 months). The mean Musculoskeletal Tumor Society Score was 27 (range 19 to 30) with a mean of 27. Nine of the ten patients with lower limb involvement were independent ambulators without additional aids. At the time of the last review, six patients were free of disease and six patients had died from the disease. There were two recurrences around the operative site. Both were associated with disseminated disease and in both the recurrences were in the soft tissue, away from the irradiated graft.

CONCLUSION

Extracorporeal irradiation is a useful, convenient technique for limb salvage in diaphyseal Ewing's sarcomas when there is reasonable residual bone stock. It is oncologically safe and has good functional results. A radiation dose of 50 Gy for sterilizing the bone ensures adequate tumor kill, while minimizing the deleterious effects on the biomechanical and biological properties of the bone. The use of appropriate implants for adequate internal fixation and supplementary bone grafting at the index surgery may help reduce the need for subsequent additional interventions to achieve union. The limitations of this procedure are that it is not applicable in tumor bones that are structurally weak and in bones with pathological fractures.

Primary endobronchial synovial sarcoma confirmed by SYT-SSX1 fusion gene transcript by reverse transcriptase polymerase chain reaction

Primary sarcomas of lung are rare compared to metastatic sarcomas. Herein, we report a rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 35-year-old lady who presented with cough and dyspnea. A malignant pulmonary tumor was suspected and left pneumonectomy was performed. Grossly, a non-encapsulated polypoidal endobronchial tumor measuring 6 cm in greatest diameter, with a solid, tan-white cut surface was identified. Microscopically, tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles. Focal hemangiopericytomatous pattern was noted. Immunohistochemically, tumor cells were positive for vimentin, BCL-2, MIC-2 and calponin and focally positive for pancytokeratin and epithelial membrane antigen. A subsequent molecular analysis performed using reverse transcriptase-polymerase chain reaction with RNA extracted from paraffin-embedded tissue, revealed SYT/SSX1 fusion gene which confirmed the diagnosis of synovial sarcoma. The utility of immunohistochemistry and molecular techniques in diagnosis of such a rare case is stressed and the relevant literature is discussed.

A t(X; 18) SYT-SSX2 positive synovial sarcoma in the pelvis of a young adult male: a rare case report with review of literature

Synovial sarcoma is uncommonly documented in the pelvis. Rarely, such cases have dealt with molecular analysis. A 19-year-old boy presented with pain and swelling in his left lower limb of two months duration. He developed acute urinary retention four days prior to his hospital admission, wherein radiological examination unraveled a large soft tissue mass, displacing his pelvic muscles, along with a lytic lesion involving his right pubic bone. Biopsy showed a cellular spindle cell sarcoma, exhibiting hemangiopericytoma-like vascular pattern with focal necrosis. Immunohistochemistry (IHC) showed positivity for vimentin, BCL-2, calponin and MIC 2. Cytokeratin (CK) and epithelial membrane antigen (EMA) were negative. MIB 1 count was 70% (high). P53 was positive. Diagnosis of a poorly differentiated synovial sarcoma was offered and confirmed with a positive t(X; 18) SYT-SSX2 translocation. This case highlights the value of molecular analysis in diagnosis of a synovial sarcoma at rare sites, especially when IHC results are equivocal and the biopsy material is limited.

Immunohistochemistry in surgical pathology practice: a current perspective of a simple, powerful, yet complex, tool

Immunohistochemistry (IHC) is a powerful tool in the surgical pathologists' armamentarium. The requests for IHC and the list of monoclonal antibodies have increased tremendously in the past decade. Issues concerning technical reproducibility, uniformity of interpretation, inter-laboratory comparability, and quality assurance are assuming greater importance due to the increased availability of IHC and its impact on diagnosis and therapy. An attempt has been made to give a current perspective of this simple and yet, in some aspects, a complex tool.

Clinicopathologic profile of 470 giant cell tumors of bone from a cancer hospital in western India

Over 20 years, 470 cases of giant cell tumor of bone diagnosed at a tertiary cancer hospital were analyzed. Male predominance (57%), predilection for bones around the knee joint (42%), and occurence in the 21- to 30-year-old age group (49.1%) with 6% being in the immature skeleton are well known facts. Accurate diagnosis was possible in 66% and 88% of cases on radiology and biopsy, respectively. Tumors measured 6 to 20 cm and, in 402 cases, showed "usual" histology comprising uniformly scattered multinucleate giant cells amidst mononuclear stromal cells, together imparting a syncitium-like appearance. Presence of osteoid, hemorrhage, and aneurysmal bone cyst-like areas; spindle cells in sheets (devoid of giant cells); or storiform pattern and intravascular osteoclasts were less common. The less common histologic features posed diagnostic difficulty in the setting of a small biopsy. Treatment included intralesional curettage (33.19%), marginal excision (4.2%), wide excision (31%), or radical surgeries (14.25%). Recurrences seen in 170 cases were multiple in 47 cases. Metastases largely to the lung were recorded in 24 cases. The histology of all the tumors, namely, primary, recurrent, or metastatic was identical. Statistical analysis using the computer software SPSS (SPSS Inc, Chicago, Ill)was performed with particular reference to the unusual histologic features vs recurrence and metastasis by chi(2) test. The only statistically significant factors were occurrence in the axial skeleton vs appendicular skeleton (P = .001) and primary treatment elsewhere vs at this hospital (P = .045), each of these being associated with increased frequency for local recurrence but not metastasis.

Diffuse-type giant cell tumor of the subcutaneous thigh

Diffuse-type giant cell tumor is an extra-articular form of pigmented villonodular synovitis. The localized form of this lesion (tenosynovial giant cell tumor) is frequent, representing the most common subset arising from the synovium of a joint, bursa or tendon sheath, with 85% of cases occurring in the fingers. The less frequent diffuse-type giant cell tumors are commonly located in the periarticular soft tissues, but on rare occasions these lesions can be purely intramuscular or subcutaneous We report the case of a 26-year-old female with diffuse-type giant cell tumor of the subcutaneous thigh, remote from a joint, bursa or tendon sheath. A review of the literature did not reveal any similar description of a diffuse-type giant cell tumor completely within the subcutaneous thigh, remote from a joint, bursa or tendon sheath. These lesions were initially regarded as inflammatory or reactive processes, but since the identification of clonal abnormalities in these patients, and in view of their capacity for autonomous growth, they are now widely considered to represent benign neoplasms.

Anaplastic large cell lymphoma (ALCL) presenting as primary bone and soft tissue sarcoma--a study of 12 cases

This study highlights the rare presentation of anaplastic large cell lymphoma as primary bone and soft tissue tumour. Twelve cases were studied. Clinical impression was non Hodgkin's lymphoma in 4 cases, sarcoma in 6 (osteosarcoma-2, Ewing's/primitive neuroectodermal tumour-1, and sarcoma NOS-3), and tuberculosis of thoracic spine in 1 and the last case involving the rib had a differential diagnosis of tuberculosis and NHL. Histology revealed round cells with eosinophilic cytoplasm and pleomorphic nuclei. Immunohistochemically all tumours were CD30 positive and 8 of 9 cases (88.9%) showed ALK-1 positivity. The pleomorphic cytomorphology ofALCL leads to confusion with the more frequent bone and soft tissue sarcomas affecting the musculoskeletal system. A high index of suspicion is necessary to initiate the correct panel of immunohistochemical markers to first confirm the lymphomatous nature of this tumour and to subsequently subclassify. This alone will lead to an accurate recognition of ALCL and the appropriate chemotherapy.

Polyphenotypic peripheral neuroepithelioma occuring in the foot: a case report

Peripheral neuroepithelioma of the soft tissues is an uncommon member of primitive neuroectodermal tumors. Divergent differentiation and polyphenotypia is known in peripheral neuroepithelioma. We report one such recurrent peripheral neuroepithelioma in an infant which was detected at one month of age, in the foot. Microscopically, it showed tumor cells in nests and lobules with abundant Homer-Wright rosettes. Immunohistochemically, tumor cells were immunoreactive for neural markers but also displayed an aberrant myoid phenotype. The prognostic implications of this anomalous phenotype are unclear as of now, but documentation of this is necessary for possible future references.

Osteoblastoma: a study of 12 cases

This study comprises of 12 cases of osteoblastoma. There were 8 males and 4 females, with a mean age of 17.8 years. The vertebral column, including the sacrum was the most frequent site (10 of 12 cases). Radiologically the lesions were lytic, well circumscribed and expansile. The histology consisted of intercommunicating osteoid seams lined by plump osteoblasts with numerous intervening ectatic stromal vessels. Despite these characteristic features, the distinction of osteoblastoma from osteoblastic osteosarcoma can at times be very problematic. The lack of lace-like osteoid or sheets of osteoblasts, and inconspicuous mitotic activity are useful distinguishing features. The purpose of this communication is to highlight the microscopic features for the correct recognition of osteoblastoma and its distinction from other osteoid forming bone lesions.

Application of the polymerase chain reaction on formalin-fixed, paraffin-embedded tissue in the recognition of tuberculous osteomyelitis

A retrospective series of 45 cases of chronic osteomyelitis collected over a period of 14 years was histologically classified into tuberculous osteomyelitis (25) and chronic non-granulomatous osteomyelitis (20). The tuberculous osteomyelitis group was divided into three subgroups: a) typical granulomas (13 cases); b) ill-defined granulomas (seven cases), and c) suspected granulomas (five cases). An in-house polymerase chain reaction amplifying the 245 bp nucleotide sequence, and capable of detecting 10 fg of DNA of Mycobacterium tuberculosis, was used on the DNA extracted from the paraffin blocks. The polymerase chain reaction was positive in 72% of cases (18) of tuberculous osteomyelitis, but when typical cases of tuberculous osteomyelitis with confirmed granulomas were considered (13), this increased to 84.6% (11). The chronic non-granulomatous osteomyelitis group gave positive polymerase chain reaction results in 20% of the cases (4).

Our preliminary study on tuberculous osteomyelitis shows that the polymerase chain reaction can be a very useful diagnostic tool, since a good correlation was seen between typical granulomas and polymerase chain reaction with a sensitivity of 84.6% and a specificity of 80%. In addition, our study shows that tuberculous osteomyelitis can be diagnosed in formalin-fixed paraffin-embedded tissues in the absence of typical granulomas.

CT-guided percutaneous core needle biopsy in deep seated musculoskeletal lesions: a prospective study of 128 cases

OBJECTIVES

Although large lesions of the limbs can easily be biopsied without image guidance, lesions in the spine, paraspinal area and pelvis are difficult to target, and benefit from CT guidance to improve the accuracy of targeting the lesion for biopsy purposes. A prospective study of CT-guided core needle biopsies for deep-seated musculoskeletal lesions was conducted at a referral cancer institute over a 4-year period with the aim of assessing the safety and efficacy of the procedure.

PATIENTS & METHODS

From January 2000 to December 2003, 136 consecutive CT-guided biopsy sessions were undertaken for musculoskeletal lesions in 128 patients comprising 73 males and 55 females. The following data was recorded in all patients: demographic data, suspected clinicoradiological diagnosis, data related to core biopsy session (date, site, approach, total time required in minutes, number of cores, surgeon satisfaction with adequacy of cores), patient discomfort, complications, histopathology report and number of further sessions if material obtained during the first biopsy session was not confirmatory. The sample obtained during the biopsy session was considered inconclusive if, in the opinion of the pathologist, inadequate or non-representative tissue had been obtained. The diagnosis was considered inaccurate if the final histopathological diagnosis did not match with the biopsy diagnosis, or if subsequent clinicoradiological evaluation at follow up did not correlate with the biopsy diagnosis in those patients who were treated with modalities other than surgery.

RESULTS

In 121 patients, a single session was sufficient to obtain representative material, whilst for six patients two sessions, and for one patient three sessions were necessary. The time taken for biopsy, including the pre-biopsy CT examination time, varied from 15 min to 60 min (median 30 min). For 110 bony lesions 116 sessions were required, and for 18 soft-tissue lesions 20 sessions were required. 108 biopsy sessions yielded a diagnosis, whilst 28 were inconclusive (diagnostic yield of 79.41%). Of 108 diagnostic biopsies, five were considered inaccurate (accuracy rate of 95.37%). The overall diagnostic yield and accuracy rate for bony lesions were 81.03% and 95.74%; and those for soft-tissue lesions were 70% and 92.85%. There were two complications with no permanent sequelae.

CONCLUSION

CT-guided core needle biopsy is a safe, easy, and effective technique for the evaluation of deep-seated musculoskeletal lesions, with a high rate of diagnostic yield and accuracy. It facilitates definitive therapy without the patient having to undergo a major surgical procedure for diagnosis.

Primary rhabdomyosarcoma of the seminal vesicle

Sarcomas of the seminal vesicle are very rare and poorly documented; as it is not always possible to pinpoint a truly vesicular origin of the pelvic mass due to local spread at the time of presentation. The purpose of the article is to document and characterize a rhabdomyosarcoma of the seminal vesicle of which to the knowledge of the authors there has been no previous report in the English literature.

Leiomyosarcoma of the esophagus

Leiomyosarcomas of the esophagus are rare, malignant, smooth-muscle tumors. The presenting symptoms are indistinguishable from other esophageal neoplasms, though the history may be longer due to the slow growth of these tumors. Barium studies may show large intramural masses with ulceration or tracking, expansile intraluminal masses or areas of luminal narrowing. Endoscopic biopsies may give a high false negative rate especially in cases where the mucosa is intact. The treatment of choice is surgical excision. Synchronous and metachronous metastases do not preclude surgery, provided the metastases are also resectable. Prognosis is better than in patients with squamous esophageal cancer. The role of adjuvant radiotherapy and chemotherapy is controversial. We report a 40-year-old man who presented to us with dysphagia and was found to have a leiomyosarcoma of the esophagus. He was treated successfully with esophagectomy and is disease-free after 7 years. We review the literature on esophageal leiomyosarcomas and their management.

Primary pleuro-pulmonary malignant germ cell tumours

Lungs and pleura are rare sites for malignant germ-cell tumours. Two cases, pure yolk-sac tumour and yolk sac-sac tumour/embryonal carcinoma are described in young males who presented with rapid progression of respiratory symptoms. The malignant mixed germ cell tumour occurred in the right lung, while the yolk-sac tumour had a pseudomesotheliomatous growth pattern suggesting a pleural origin. Alpha-foetoprotein was immunohistochemically demonstrated in both.

Benign metastasizing chondroblastoma: a case report

BACKGROUND

Metastasis of histologically benign chondroblastoma is a rare event. The authors report a new case, 12th in the literature, wherein multiple lung metastases appeared almost simultaneously with the primary lesion in the right talus bone.

METHODS

A histologic evaluation of the primary lesion in the talus and the pulmonary metastasis was performed, and an ultrastructural study of the latter was done. Published literature on metastasizing chondroblastoma was reviewed to identify any consistency in the pattern and the outcome.

RESULTS

Metastasis of chondroblastoma is uncommon but well known. Although radiologic and histologic aggressive features have been sought, they do not necessarily correlate with the outcome.

CONCLUSIONS

Metastasis in chondroblastoma has been insufficiently stressed in the literature, unlike metastasis in giant cell tumors. The purpose of this case report is not only to document this uncommon event (the 12th case of lung metastasis) but also to emphasize that patients with chondroblastoma may have metastasis at presentation. Hence, all patients need to be evaluated regularly from the onset for possible lung metastasis so that deposits can be detected early for total resection.

Primary multilocular cystic undifferentiated (embryonal) sarcoma of the liver in childhood resembling hydatid cyst of the liver

Undifferentiated (embryonal) sarcoma (UES) is a very rare primary malignant tumour of the liver; typically presenting in later childhood. This tumour usually appears on CT and ultrasound as a predominantly solid mass with or without cystic areas. We report a case of primary UES which had a multilocular cystic appearance resembling a hydatid cyst on imaging.

Fine needle aspiration cytology of undifferentiated (embryonal) sarcoma of the liver: a case report

BACKGROUND

Undifferentiated sarcoma of the liver is a rare tumor of childhood. The histology has been well documented, but the histogenesis is controversial. The cytologic characteristics of this neoplasm in aspiration material have not been previously documented.

CASE

The cytologic features in a 9-year-old male were pleomorphic malignant cells, multinucleate giant cells, numerous hyaline globules and myxoid matrix.

CONCLUSION

The cytologic features of undifferentiated sarcoma of the liver are distinctive and different from those of other childhood liver tumors. Awareness of the tumor's cytomorphology can result in a confident preoperative diagnosis.

The neurotropic variant of desmoplastic spindle cell melanoma of the foot--a report of two cases with special reference to its schwanian features

Melanomas are known to show a wide range of morphological expression. Desmoplastic Malignant Melanoma (DMM) which is a variant of spindle cell melanoma, is often characterised by conspicuous growth in and around nerves which leads to a mistaken diagnosis of malignant Peripheral Nerve Sheath tumours (MPNST). We report two such cases of spindle celled DMM of the foot which displayed neurotropism. The problems and the clinical relevance of distinguishing this variant of melanoma from MPNST is discussed.

Melanotic neuroectodermal tumor of infancy: report of a case with ganglionic differentiation

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare but well-documented lesion of neuroectodermal derivation. Maturation of the neural elements has been reported only occasionally. We report a case of MNTI of the maxilla showing maturation of neural elements to ganglionic cells.

Primary endodermal sinus tumor of the penis: a case report

We report a case of primary extragonadal germ cell tumor of the penis in a 2-year-old child with elevated serum alpha-fetoprotein. The patient responded well to a combination of bleomycin, etoposide and cisplatin, achieving a complete response within 3 cycles. He was alive and disease-free 8 months after diagnosis. To our knowledge this is the first case of an endodermal sinus tumor of the penis reported in the literature. The possible histogenesis of this tumor at such a rare site is discussed.

Intrahepatic cholangiocarcinoma: report of a surgically resected case

We report a middle aged female with intrahepatic cholangiocarcinoma which was resected successfully. Because of an unusual histology, a microscopic diagnosis could not be established pre-operatively. The tumor recurred locally 21 months after surgery. The case is reported mainly for the diagnostic problems it created.

Angiolymphoid hyperplasia with eosinophilia (Kimura's disease): report of a large-sized lesion

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon lesion with a predilection for skin of the head and neck region. It usually presents as one or a few smooth-surfaced nodules which are often asymptomatic. Histologically the nodules reveal two components: abnormal proliferating vessels and a cellular infiltrate consisting of lymphocytes and eosinophils, involving both the dermis and the subcutaneous tissue. A case is presented of an unusually large recurrent lesion on the scalp.

Primary lymphoma of bone: a clinicopathologic study of 25 cases reported over 10 years

Twenty-five cases of primary lymphoma of bone (PLB) reported over a 10-year period were reviewed. The presenting symptom was related to involvement of a single bone with or without regional nodal disease. None showed dissemination of lymphoma in the subsequent six months. Patients affected were 7-65 years of age. An equal predilection for the axial and appendicular skeleton was noted. Histologically, the commonest subtype was diffuse histiocytic lymphoma (DHL, 17 cases), whereas four were poorly differentiated lymphocytic (PDL) type and another four were unclassifiable. Follow-up was available in 18 out of 25 patients for periods ranging from 7 months to 8 years. On clinicopathologic correlation we found that 75% of disease-free patients had a DHL whereas 60% of those alive with disease had a PDL. This study reiterates the view that PLB has a good prognosis and the DHL subtype is especially amenable to complete eradication.

Monoclonal antibody against human squamous-cell-carcinoma-associated antigen

Mouse monoclonal antibody (MAb) 3F8E3 (IgG3k) was developed against the head and neck cancer cell line LICR-LON-HN2. Subjected to indirect immunofluorescence, the MAb reacted exclusively with SCC cell lines and showed no reactivity with normal or transformed mouse and human non-SCC cell lines and hematopoietic cell lines. The radiolabelled MAb showed an affinity constant of 1.8 x 10(8) M-1 with HN2 cells and identified 2.07 x 10(4) sites/cell by Scatchard analysis. It identified 2 peptides from membrane extracts of HN2 cells by Western blotting. Avidin-biotin-complexed immunoperoxidase staining on cryostat sections of tumors from various tissues revealed that 3F8E3 reacted mainly with the membrane antigens of well differentiated SCC cells of oral cavity, larynx, esophagus, lung, uterine cervix, metastatic nodes of patients with oral cancer, and dysplastic cells in oral leukoplakia. The MAb did not react with poorly differentiated cells of Ca esophagus, adenocarcinoma of breast, stomach and colon, renal-cell carcinoma and soft-tissue sarcoma.

Simultaneous endometrioid carcinoma of the uterine corpus and ovary: a clinicopathologic study of 15 cases

The clinical stage assigned to simultaneously presenting carcinomas of the uterine corpus and ovary remains variable, depending on which of the two sites is considered to be the primary. Simultaneous involvement may occasionally represent independent primaries, a fact often overlooked. A review of all cases with a tissue diagnosis of carcinoma involving uterus and ovary was undertaken to identify those cases which possibly represent independent primaries. Seventeen such cases were identified on the basis of pathologic features, 15 of which revealed endometrioid type carcinoma at both sites. These 15 patients, who constitute the study group, were treated surgically with or without adjuvant therapy. Thirteen patients have been followed up for 1 to 12 years. Twelve patients are alive and free of disease. Vaginal vault recurrence occurred in a single patient. This was treated successfully. One patient died of an unrelated cause. The good survival fortifies the pathological impression that these cases represent independent primaries.