Spindle cell carcinoma of the lung. A clinicopathologic study of three cases

Primary Pulmonary Carcinomas with Spindle and/or Giant Cell Features: A Review with Emphasis in Classification and Pitfalls in Diagnosis

Primary carcinomas of the lung are vastly represented by the conventional types of adenocarcinomas or squamous cell carcinomas. However, there are other types of non-small cell carcinomas that although uncommon represent a meaningful group that often pose a problem not only in diagnosis but also in classification. Spindle cell and/or giant cell carcinomas, although uncommon represent an important group of primary lung carcinomas. Important to highlight is that current criteria are rather ambiguous and likely not up to date, which renders the classification of these tumors somewhat more obscure. In addition, with the daily use of immunohistochemical stains, the classification of these tumors may also pose a different problem in the proper allocation of these tumors. Proper classification is highly important in the selection process that takes place using such material for molecular analysis. The current molecular characteristics of these tumors are limited and lack more in-depth studies and analyses that can provide specific targets for the treatment of patients with these tumors. The current review attempts to highlight the shortcomings in the current classification and definitions of these neoplasms as well as the more current view regarding these tumors when the use of immunohistochemical stains is employed.

Stereotactic body radiation therapy (SBRT) in the management of pulmonary spindle cell carcinoma

A 69-year-old woman underwent routine screening with CT scan of the chest, which showed a new right upper lobe lesion. Interval increase in size of the right upper lobe nodule over 3 months, prompted a CT-guided biopsy of the lung that confirmed a diagnosis of malignant pulmonary spindle cell carcinoma (PSCC) with 90% programmed death ligand 1 expression. Positron emission tomography CT demonstrated localised stage IIA disease. Given histologically proven PSCC and the rapid growth of her tumour, curative radiation with stereotactic body radiation therapy (SBRT) to the right upper lobe primary tumour was planned as patient was deemed not to be a surgical candidate. Repeat imaging with a CT chest 2 months after SBRT demonstrated good local control of the primary disease in the right upper lobe despite rapidly advancing distant metastasis. The patient continues systemic therapy with pembrolizumab, to which she has shown good response.

Pulmonary Sarcomatoid Carcinomas: A Review

Pulmonary sarcomatoid carcinomas belong to a group of neoplasms that remain incompletely understood. They are rare tumors of the bronchopulmonary system that incorporate a wide range of neoplasms that by definition contain a sarcomatoid component characterized by spindle or giant cells. Such classification has led to a heterogenous tumor category that includes neoplasms with different clinical, morphologic, and prognostic features. To date, the histopathologic diagnosis of pulmonary sarcomatoid carcinomas does not require the use of ancillary testing and is based on light microscopic criteria alone. However, with recent advances in immunohistochemical and molecular methods, it is becoming increasingly clear that pulmonary sarcomatoid carcinomas represent poorly differentiated or "dedifferentiated" variants of conventional non-small cell carcinomas with similar immunophenotype and molecular signatures. This review summarizes the latest insights and concepts of these unusual tumors and outlines future directions with emphasis on tumor classification and patient management.

Sarcomatoid carcinoma of the lung: a rare histological subtype of non-small cell lung cancer with a poor prognosis even at earlier tumour stages

Objectives

Pulmonary sarcomatoid carcinoma (PSC) is a rare histological subtype of non-small cell lung cancer and comprises a diagnostically and therapeutically challenging group of tumours. We explored the clinicopathological features and prognostic factors of this tumour.

Methods

We conducted a retrospective study of all patients who were treated for PSC in the Department of Thoracic Surgery between May 2005 and December 2014. Primary outcomes of interest were patient survival and prognostic factors.

Results

A total of 58 patients were treated for sarcomatoid carcinoma within the described period and 46 patients underwent surgical resection with curative intent. The mean follow-up period was 30 months. Of the operated patients, 21.7% had pathological stage I disease, and 78.3% had more advanced disease. There were 25 carcinosarcomas, 10 pleomorphic carcinomas, 7 spindle cell carcinomas, 3 giant cell carcinomas and 1 pulmonary blastoma. Overall 5-year survival of the operated patients was 28.7%. A total of 28 patients experienced recurrence and died cancer-related. Our analysis revealed that tumour size, gender, histological entity, lymphatic vessel invasion (L1) and vascular invasion (V1) did not influence survival. There was a trend for decreased survival in older patients (>65 years).

Conclusions

Surgical treatment can achieve satisfactory results with low perioperative mortality, but the overall prognosis even with multimodality concepts and in earlier tumour stages is worse compared to other types of non-small cell lung cancer.

Pulmonary spindle cell carcinoma with unusual morphology: A rare case report and review of the literature

RATIONALE

Pulmonary spindle cell carcinoma (PSCC) is a highly malignant carcinoma that often exhibits the histopathological characteristic of cell pleomorphism.

PATIENT CONCERNS

Here, we report a PSCC case in a 59-year-old woman with multiple metastases. The pathological manifestation of this case did not show high-grade pleomorphism or atypia, and was easily mimicked by other borderline or low-grade malignant tumors such as an inflammatory myofibroblastic tumor (IMT).

DIAGNOSES

Based on the results of immunohistochemistry and fluorescence in situ hybridization after the operation, IMT was ruled out, and PSCC was confirmed.

INTERVENTIONS

Resection of the right middle lobe and dissection of the lymph nodes were performed. The patient was given 2 cycles of chemotherapy with cisplatin and 1 cycle of radiotherapy after the operation.

OUTCOMES

Metastatic lesions in the left kidney, the right lung, the first thoracic vertebrae, the retroperitoneal lymph nodes, and the mediastinal lymph nodes were identified by positron emission tomography/computed tomography 4 months after the operation, and the patient died 2 months later.

LESSONS

PSCC is a highly malignant carcinoma, but it rarely shows a low-grade malignant histological morphology. So, efforts should be focused on differentiating it from other borderline or low malignant tumors (such as IMT) to avoid misdiagnosis.

An Autopsy Case of Rapidly Progressing Spindle Cell Carcinoma of the Lung Accompanied with Intratumor Hemorrhage

Patient: Male, 74

Final Diagnosis: Spindle cell carcinoma of the lung

Symptoms: —

Medication: Pemetrexed • carboplatin

Clinical Procedure: Biopsy and autopsy

Specialty: Oncology

[Pleomorphic carcinoma of the lung: a case report]

Pleomorphic carcinoma is a rare malignancy belonging to the family of nonsmall cell lung cancers. A 40-year-old man, a smoker, was hospitalized for thoracic pain and dry cough with a deteriorating general condition. The imaging showed a "drop ball" of both lungs. The pathological evidence was obtained by lung biopsy under scanographic control. The presence of supraclavicular and abdominal nodes classified the tumour as stage IV. The patient received six cycles of first-line chemotherapy associating cisplatin and vinorelbine. However, the disease continued to progress and distant metastases were observed. The patient died 6 months after the diagnosis. Pleomorphic carcinoma is identified by purely histological criteria: the concomitant presence of malignant epithelial and homologous sarcomatoid spindle-cell components. Like the other nonsmall cell lung cancers, the treatment is primarily surgical, and the invasive nature of this tumour makes it very difficult. Pleomorphic carcinoma has a poorer prognosis than conventional nonsmall cell lung cancers despite surgery, irradiation and chemotherapy, because relapse occurs early.

Review article: pulmonary sarcomatoid carcinomas: a practical overview

Pulmonary sarcomatoid carcinomas (PSCs) are currently defined as poorly differentiated non-small-cell carcinomas containing a component with sarcoma or sarcoma-like (spindle and/or giant cell) features. They consist of 5 major histological variants, namely pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma, and pulmonary blastoma. The segregation of PSCs into a distinct clinicopathologic entity seems justified on the basis of morphologic, behavioral, and genotypic/phenotypic attributes. As a group, PSCs generally run an aggressive clinical course and may cause major difficulties in the differential diagnosis with other primary and secondary malignancies of the lung. At present, PSCs are believed to represent a family of carcinomas "in transition," in which diverse pathways of clonal evolution account for histological differences of a common ancestor lesion. The sarcomatous or sarcomatoid component of these tumors is thought to derive from carcinoma cells during the progression of carcinogenesis through the activation of an epithelial-mesenchymal transition program leading to sarcomatous transformation or metaplasia (conversion paradigm). Conceivably, targeting the epithelial-mesenchymal transition program could become a valid therapeutic strategy for these life-threatening tumors, whose sensitivity to current medical manipulation is disappointing.

Pulmonary Sarcomatous Tumors

Context.—Sarcomatous pulmonary neoplasms are a rare and diagnostically challenging group of tumors. Primary pulmonary sarcomas must be distinguished from the more frequent occurrence of sarcoma metastatic to the lung, primary pulmonary sarcomatoid carcinoma, and diffuse malignant mesothelioma involving the lung. In current practice, the general availability of ancillary diagnostic techniques, such as immunohistochemistry and molecular analysis, can reliably classify many sarcomatoid lesions.

Objective.—To review the literature and report on additional primary material about the application of immunohistochemistry and molecular analysis in the differential diagnosis pulmonary sarcomatous neoplasms.

Data Sources.—Literature review of relevant articles indexed in PubMed (National Library of Medicine) between 1961 and 2007 and primary material from the author's institution.

Conclusions.—This review discusses specific criteria for the diagnosis of primary lung sarcomas and offers a practical approach to excluding other sarcoma-like lesions involving the lung. The pathologist has an essential role in evaluating these tumors and will often be the first to suggest an unusual, alternative diagnosis, which may have significant implications for patient care, therapy, and prognosis.

Sarcomatoid carcinoma of the lung: a predictor of poor prognosis

BACKGROUND

Sarcomatoid cancer (SARC) of the lung is a rare histologic type of non-small cell lung cancer (NSCLC). Although believed to be associated with poor prognosis, its effect on survival and recurrence has not been well defined. Our goal was to determine the prognostic significance of SARC histology in patients undergoing pulmonary resection.

METHODS

We retrospectively evaluated all patients who underwent pulmonary resection for NSCLC during a 20-year period at the University of Texas MD Anderson Cancer Center and compared recurrence and survival rates of patients with SARC with a cohort of patients with typical NSCLC. To account for known prognostic factors such as smoking status, age, gender, pathologic stage, and adjuvant therapy, we used one-to-one matching based on propensity scores.

RESULTS

The study included 63 SARC patients and 1133 NSCLC patients with complete data. Propensity score matching identified 63 NSCLC patients that were similar to the 63 SARC patients from known clinical factors. The 5-year survival for SARC patients was 24.5% compared with 46.3% for NSCLC patients (p = 0.01); median time to recurrence was 11.3 months and 61.4 months, respectively (p = 0.001).

CONCLUSIONS

Compared with other histologic subtypes, SARC behaves in an aggressive fashion. These tumors are frequently symptomatic, are locally advanced, and have higher rates of recurrence. Future investigation of novel treatment approaches is warranted. Nonsurgical treatment modalities may be appropriate for patients with clinically advanced disease.

[A rare primary pulmonary tumor: pleomorphic carcinoma]

INTRODUCTION

Pleomorphic carcinoma is a rare malignancy in the family of non-small cell lung cancers.

CASE

This 65-year-old woman, a nonsmoker, was hospitalized for hemoptysis and weight loss. Computed tomography showed a peripheral tumor of the right upper lobe, and the radiography showed signs of malignancy. Pathologic examination of the transparietal biopsy confirmed the tumor diagnosis, classifying it as stage III A. The patient underwent 2 cycles of induction chemotherapy that combined gemcitabine and cisplatin. Disease progression continued, however, and distant metastases were observed. The patient died 4 months after diagnosis.

DISCUSSION

Pleomorphic carcinoma is identified by purely histologic criteria: the concomitant presence of malignant epithelial and homologous sarcomatoid spindle-cell components. Like the other non-small cell lung cancers, treatment is primarily surgical, and the invasive character of this tumor makes it very difficult. Pleomorphic carcinoma has a poorer prognosis than conventional non-small cell lung cancers despite surgery, irradiation and chemotherapy, because relapse occurs early.

Primary undifferentiated spindle-cell carcinoma of the gallbladder presenting as a liver tumor

Undifferentiated spindle-cell carcinoma (SpCC) of the gallbladder is extremely rare. There is very little information available regarding the characteristics and treatment of this disease. We herein report the unique case of a 76-year-old female patient with a primary SpCC of the gallbladder that presented as a liver tumor. Preoperative radiologic examinations showed a 5-cm liver tumor around the gallbladder bed, and irregular thickening of the gallbladder wall. The patient underwent en-bloc resection of the gallbladder and segments 4b and 5 of the liver (including the liver tumor). Microscopic findings revealed that both lesions consisted mainly of a sarcomatous spindle-shaped component. Small foci of well-differentiated adenocarcinoma cells were identified in the gallbladder mucosa. There was a gradual transition between the two different components, thereby implying that these two cell types had a common origin. Immunohistochemical studies showed that the spindle-shaped cells were epithelial in nature. The patient's postoperative course was uneventful. However, she died of recurrent liver disease 6 months after the surgery. In conclusion, we surmised that the sarcomatous spindle cells originated from a carcinomatous component in the gallbladder mucosa through dedifferentiation. Further studies are needed to better understand the characteristics of this deadly tumor, and to establish an effective therapy for it.

Personal Experience in Surgical Management of Pulmonary Pleomorphic Carcinoma

BACKGROUND

Pleomorphic carcinoma is a rare epithelial malignant tumor. Pulmonary pleomorphic carcinoma was introduced by the 1999 World Health Organization classification as a new peculiar type of lung carcinoma showing concurrent malignant epithelial and sarcomatoid spindle cell elements. Few reports describe its clinical behavior. My colleagues and I report a series of patients surgically treated for pulmonary pleomorphic carcinoma to describe our experience with this malignant neoplasm.

METHODS

Twenty cases of pleomorphic pulmonary carcinoma were collected and studied clinicopathologically. All patients underwent surgical resection. The cases were as follows: 6 stage I, 12 stage II, and 2 stage IIIA. Histologic diagnosis was established by using light microscopic examination and immunohistochemistry. Survival rates were calculated with the Kaplan-Meier method.

RESULTS

We postoperatively diagnosed 20 cases of pleomorphic carcinoma: 14 cases were exclusively spindle and giant-cell carcinomas, 2 cases were spindle and giant-cell carcinoma combined with adenocarcinoma, 2 were combined with squamous cell carcinoma, and 2 were combined with large cell carcinoma. At last follow-up, 4 patients were still alive; they were postoperative T1 N0 and T2 N0. The remaining 16 patients died from early distant metastases. The median duration of disease-free survival was 5 months. The median duration of overall survival was 8 months.

CONCLUSIONS

The prognosis of patients with pleomorphic carcinoma was poor, despite surgery and adjuvant chemotherapy, because of early relapse of disease. Nodal involvement was a determinant prognostic variable, because advanced stages were related to worse prognosis. In case of preoperatively proven pulmonary pleomorphic carcinoma, surgery should be recommended to N0 patients.

K-ras gene mutational analysis supports a monoclonal origin of biphasic pleomorphic carcinoma of the lung

We investigated 27 pleomorphic carcinomas of the lung for exon 1 K-ras gene mutations using polymerase chain reaction-single-strand conformation polymophism analysis and direct sequencing. All pleomorphic carcinomas were biphasic, that is, composed of an adeno-, squamous- or large-cell-carcinomatous component associated with a spindle- and/or giant-cell component. Of 27 cases, six (22%) showed K-ras codon 12 mutations, which is a figure higher than that previously reported on in pure sarcoma-like pleomorphic carcinomas. Five tumors displayed the same mutation in both the epithelial and the sarcomatoid components, whereas in one tumor the mutation was restricted to the epithelial component. All mutations occurred in smokers, and were transversions, including GGT (glycine) to TGT (cysteine) change in two cases, to GCT (alanine) in two and to GTT (valine) in two. No significant relationships were found between the occurrence and type of mutations and patients' survival or any other clinicopathological variable, suggesting that K-ras mutations are early events in the development of these tumors. Our results indicate that most, though not all, biphasic pleomorphic carcinomas of the lung are monoclonal in origin, and that cigarette smoking may have a causative role in the development of K-ras alterations in these tumors, as all mutations are transversions.

Pleomorphic carcinomas of the lung show a selective distribution of gene products involved in cell differentiation, cell cycle control, tumor growth, and tumor cell motility: a clinicopathologic and immunohistochemical study of 31 cases

We investigated 31 cases of pleomorphic carcinomas of the lung, with a double component of neoplastic epithelial cells and of spindle and/or giant cells. To correlate the morphologic diversity of these two cell components with their immunophenotype, we evaluated the expression of several gene products involved in cell differentiation (cytokeratins, epithelial membrane antigen, carcinoembryonic antigen, vimentin, S-100 protein, smooth muscle actin, desmin), cell cycle control and apoptosis (p53, p21Waf1, p27Kip1, FHIT), tumor growth (proliferative fraction, assessed by Ki-67 antigen, and microvascular density, assessed by CD34 immunostaining), and tumor cell motility (fascin). We found the epithelial component to be significantly more immunoreactive for cytokeratins, epithelial membrane antigen, carcinoembryonic antigen, cell cycle inhibitors p21Waf1, p27Kip1 and tumor suppressor gene FHIT, whereas the sarcomatoid component, independent of tumor stage and size, was more immunoreactive for vimentin, fascin, and microvascular density. Accordingly, we suggest a model of tumorigenesis whereby the mesenchymal phenotype of pleomorphic cells is likely induced by the selective activation and segregation of several molecules involved in cell differentiation, cell cycle control, and tumor cell growth and motility. Whether pleomorphic carcinomas of the lung are tumors with a dismal prognosis still remains an unsettled issue. In our series, however, stage I pleomorphic carcinomas have the same clinical behavior as ordinary non-small cell lung cancer, and only a high proliferative index (Ki-67 labeling index >35%) is associated with a worse prognosis in these tumors.

Pulmonary carcinomas with pleomorphic, sarcomatoid, or sarcomatous elements: a clinicopathologic and immunohistochemical study of 75 cases

We collected 75 primary pulmonary carcinomas with pleomorphic, sarcomatoid, or sarcomatous elements to better define their clinical, histologic, and immunohistochemical profile. The patient's age ranged from 42 to 81 years (mean 65 years), and the male-to-female ratio was 9.7:1. Sixty-nine patients (92%) were smokers. Cough and hemoptysis were the most frequent presenting symptoms. Fifty-nine patients (65%) died of disease: only stage significantly predicts overall survival (p = 0.0273). Microscopically, based on the WHO criteria, 58 cases were classified as pleomorphic carcinoma (51 with an epithelial component, 7 composed exclusively of spindle and giant cells), 10 as spindle cell carcinoma, 3 as giant cell carcinoma, 3 as carcinosarcoma, and 1 as pulmonary blastoma. Immunohistochemically, in the tumors composed exclusively of spindle and/or giant cells, thyroid transcription factor-1 (TTF-1) and cytokeratin 7 were positive in 55% and 70% of the cases, respectively, whereas surfactant protein-A was always negative. In pleomorphic carcinomas with an epithelial component, cytokeratin 7, TTF-1, and surfactant protein-A were positive in the sarcomatoid component in 62.7%, 43.1%, and 5.9% of the cases, respectively, whereas they were always negative in the sarcomatous part of carcinosarcomas and blastoma. In the epithelial component of pleomorphic carcinomas, cytokeratin 7, TTF-1, and surfactant protein-A were positive in 76.4%, 58.8%, and 39.2% of the cases, respectively, whereas the same antibodies did not react with the epithelial component of carcinosarcomas; in the case of blastoma, the epithelial part of the tumor was positive for cytokeratin 7 and TTF-1, whereas it was negative for surfactant protein-A. Cytokeratin 20 was always negative. In our opinion, this study: 1) supports the metaplastic histogenetic theory for this group of tumors; 2) shows that cytokeratin 7 and TTF-1, but not surfactant protein-A, are useful immunohistochemical markers in this setting; 3) confirms that stage is at the moment the only significant prognostic parameter, as in conventional non-small cell lung carcinomas; and 4) shows that this group of tumors has a worse prognosis than conventional non-small cell lung carcinoma at surgically curable stages I, justifying their segregation as an independent histologic type in the WHO classification.

Molecular pathogenesis of pulmonary carcinosarcoma as determined by microdissection-based allelotyping

Pulmonary carcinosarcoma is a rare, biphasic tumor composed of malignant epithelial and mesenchymal elements. Its histogenesis is controversial in light of the presence of divergent cell lineages and the clonal nature of malignancy. To address these issues, we performed an extensive comparative genotypic analysis using microdissection to secure representative mesenchymal and epithelial components from each of six cases of pulmonary carcinosarcoma. Loss of heterozygosity was analyzed with a panel of 12 polymorphic microsatellite markers designed to indicate allelic loss and situated in proximity to known tumor suppressor genes located on 1p, 3p, 5q, 9p, 10q, and 17p. In accordance with the relatively greater biologic aggressiveness of this tumor type, both the epithelial and mesenchymal components showed extensive allelic loss, most notably for 3p, 5q, and 17p. More importantly, we found overall equivalent patterns of acquired allelic loss between the two components on an individual case basis, strongly supporting the monoclonal origin of these neoplasms. Minor differences in the allelic fingerprint between the two cell lineages could be explained by progressive accumulation of allelic loss alterations that appear to occur more frequently in the mesenchymal component of the tumor. The data support the efficacy of microdissection-based allelic fingerprinting to delineate the relationship between different morphologic components of a single neoplasm.

Sarcomatoid/metaplastic carcinoma of the breast: a clinicopathological study of 12 cases

AIMS

To analyse the clinical and pathological features with long-term follow-up of a series of 12 cases of sarcomatoid carcinoma of the breast. methods and results: The cases were selected from the surgical files of the Department of Pathology, University of Edinburgh, between 1977 and 1988. The following clinical parameters were recorded: the age of the patients, size of tumour, presence or absence of lymph node or distant metastases, and patient survival. Pathological assessment included: the type of epithelial and mesenchymal components, the proportion of monophasic to biphasic tumours and the presence of adjacent in-situ carcinoma/atypical epithelial proliferation. The mean age of the patients was 61 years with a median of 64 and range 46-82 years. The mean size of the tumour was 52 mm (range 22-100 mm). None of the patients had distant metastasis at presentation and only one case had local lymph node metastasis which had a carcinomatous appearance. Five women were still alive after a minimum 12-year follow-up period. Four patients died of their disease (three with lung metastasis only and one with lung and bone metastases), one died of carcinoma of the cervix and two patients were lost to follow-up. Pathologically, four cases (33.3%) had no or almost undetectable epithelial structures by light microscopy, i.e. "monophasic sarcomatoid carcinoma". The remaining cases revealed varying proportions of both epithelial and mesenchymal elements, i.e. "biphasic sarcomatoid carcinoma". Of the epithelial component, six (50%) tumours had predominantly carcinoma of no special type, one lobular and one tubular carcinoma. The mesenchymal component was fibromatosis/nodular fasciitis-like, malignant fibrous histiocytoma-like (MFH), osteosarcoma-like and fibrosarcoma-like in five (42%), four (33%), two (17%) and one (8%) tumours, respectively. In 3/4 monophasic tumours, the mesenchymal component was of a low-grade fibromatosis/nodular fasciitis type. In 6/12 (50%) of the cases there was associated in-situ atypical epithelial proliferation (five ductal carcinoma in situ (DCIS) and one atypical ductal hyperplasia).

CONCLUSIONS

From this small series it appears that sarcomatoid carcinoma is an uncommon tumour, which is large in size and tends to lack local or distant metastasis at presentation. Pathologists should be alert to the presence of the bland monophasic sarcomatoid carcinoma which has a pure mesenchymal appearance on light microscopy, but epithelial components demonstrated by cytokeratin immunohistochemistry. These showed metastases on long-term follow-up, similar to other histological patterns of sarcomatoid carcinoma.

Pulmonary pleomorphic (spindle) cell carcinoma: peculiar clinicopathologic manifestations different from ordinary non-small cell carcinoma

Pleomorphic (spindle) cell carcinoma, also known as monophasic sarcomatoid carcinoma, is a rare primary pulmonary malignancy. This type of tumor shows concurrent presence of malignant epithelial and homologous sarcomatoid spindle cell components by co-expressing cytokeratin and vimentin in various degrees. Sixteen cases (four central endobronchial lesions and 12 peripheral parenchymal masses) were studied clinicopathologically. Men were affected far more frequently than women (13:3). The patients were between 56 and 80 years of age. The disease is strongly associated with smoking. Among seven of the patients who underwent surgical resection, four of them had mediastinum, pleura and chest wall invasions, and three of them had regional lymph node metastases. All of the patients succumbed to early distant metastases (range 2 weeks-5 months) in organs including brain, bone, adrenal gland, and unusual sites such as esophagus, jejunum, rectum and kidney. The remaining nine inoperable cases were late stage disease and treated with chemoradiotherapy with little effect. The median duration of survival was 3 months. All parenchymal masses appeared as cavities with marked central necrosis, and only peripheral rim of tumor cells was left. More definite diagnostic results will depend on further tissue sections and can be confirmed by immunohistochemical studies. Significantly fewer Ki-67, p53 and c-erb B-2 oncoprotein expressions were also noted.

Spindle cell tumours of the breast: practical approach to diagnosis

Spindle cell tumours of the breast are uncommon and often present diagnostic challenges. The most important is the sarcomatoid/metaplastic carcinoma, which has monophasic and biphasic variants. Each of these groups presents special diagnostic difficulties. In the monophasic variant the mesenchymal component predominates and the epithelial element forms a minor component often detected only after immunohistochemical study. The spindle cell areas may be bland and therefore under-diagnosed as nodular fasciitis or fibromatosis. Alternatively they may be highly malignant with a pattern that is misinterpreted as primary sarcoma of the breast. In the biphasic variant, the difficulty is in distinguishing between sarcomatoid carcinoma, myoepithelial carcinoma or malignant phyllodes tumour. Other spindle cell lesions of the breast include the various myofibroblastic tumours, the spindle cell variant of adenomyoepithelioma, the varied primary breast sarcomas, metastatic tumours with spindle cell morphology and, finally, the very rare follicular dendritic cell tumour. A simple practical approach to the diagnosis of spindle cell lesions is presented to help the general surgical pathologist to compile a differential diagnosis and to arrive at the correct conclusion

Spindle cell squamous carcinoma of the esophagus: analysis of ploidy and tumor proliferative activity in a series of 13 cases

Spindle cell squamous esophageal carcinomas are distinctive polypoid "biphasic" tumors in which the sarcoma-like phenotype usually predominates over the epithelial component. To biologically assess both phenotypes, we compared the tumoral proliferative activity and DNA ploidy between the two histological components of 13 polypoid spindle cell squamous carcinomas of the esophagus. We studied the tumoral proliferative index (TPI) using MIB 1 monoclonal antibody (Ki-67) and determined the DNA histogram by image cytometry on Feulgen-stained sections. The DNA histograms were classified into four types (I to IV) according to the degree of dispersion of the DNA. The TPI of the carcinomatous regions ranged from 0.20 to 0.63 (mean, 0.44) and from 0.55 to 0.85 for the sarcoma-like areas (mean, 0.68) P < .0001. In all cases, the sarcoma-like areas were aneuploid, and 37.5% of the carcinomatous regions were diploid. Also, in all instances the carcinomatous areas were of either histogram type I or II, and the sarcoma-like areas showed histograms of type II or III. We conclude that in esophageal spindle cell squamous carcinomas the sarcoma-like phenotype differs biologically in two ways from the carcinomatous: (1) it has a higher TPI and (2) it has higher aneuploidy with a greater dispersion of the DNA content. We postulate that these characteristics could give a "growth" advantage to the sarcoma-like component of these tumors and explain its predominance over the carcinomatous component.

Sarcomatoid carcinomas: pathological and histopathogenetic considerations

Malignant tumors with a mixed phenotype are a controversial field of pathology. In this article the morphological aspects and the immunohistological characterization of sarcomatoid carcinomas are presented. These uncommon neoplasms show both carcinomatous and sarcomatous features, and have been described in the past under a variety of different names causing great uncertainty about their classification and histogenesis. They can occur in various anatomical sites and exhibit a wide range of microscopic appearances, but some features are quite characteristic and are found in many cases. Morphological "transition" between carcinomatous and sarcomatous tissue, and detection of epithelial characteristics by electron microscopy or immunohistochemistry in the sarcomatous component, are very peculiar features of these neoplasms, providing both helpful clues for pathological diagnosis and important insights into histogenesis. Here a unifying histopathogenetic mechanism based on the phenotypic conversion of carcinoma into sarcomatoid tissue is proposed and supporting literature data from both experimental systems and clinicopathological observations are reviewed and discussed.

Spindle cell hepatocellular carcinoma. A clinicopathologic and immunohistochemical analysis of 15 cases

BACKGROUND

Spindle cell hepatocellular carcinoma (SpHCC) has rarely been reported, and its clinicopathologic characteristics, histogenesis, and prognosis after hepatic resection have yet to be clarified.

METHODS

Fifteen cases of SpHCC, including 13 surgically resected patients and 2 autopsy cases, were studied clinicopathologically and immunohistochemically.

RESULTS

In 13 resected patients, all except 1 were male and the serum alpha-fetoprotein (AFP) was positive in 6 (46%). Portal venous invasion and intrahepatic metastases were frequent. In an immunohistochemical analysis of 13 SpHCC tumors, cytokeratin CAM 5.2 and AFP were positive in 8 (62%) tumors and 3 (23%) tumors in both ordinary HCC and spindle cell components, respectively. The spindle cell components, but not ordinary HCC components, revealed a positive reaction for vimentin in 8 (62%) tumors, S-100 protein and HAM-56 in 3 (23%) tumors, HHF-35 in 2 (15%) tumors, and alpha-smooth muscle actin, desmin, and KP-1 in 1 (8%) tumor, respectively. p53 overexpression was found in two SpHCC tumors. The survival curve after hepatic resection in the 13 patients with SpHCC was significantly worse than that of the 371 patients with Stage II-IV ordinary HCC (P < 0.001).

CONCLUSIONS

These results suggest that SpHCC represents a sarcomatous transformation of HCC. The spindle cell components revealed an immunohistochemical expression of several markers of mesenchymal cells. In addition, poor survival after hepatic resection was documented.

Alteration of the p53 gene of lung carcinomas with sarcomatous transformation (spindle cell carcinoma): analysis of four cases

Lung carcinoma with sarcomatous transformation (LCST) is highly aggressive and characterized by local invasion and/or distant metastasis, which leads to a shorter survival than ordinary lung carcinomas. Therefore, to elucidate whether the malignant potential of the spindle cell element in LCST is associated with the alteration of the p53 gene, four cases were examined by analyses of overexpression of the p53 oncoprotein, mutation of the p53 gene and loss-of-heterozygosity (LOH) at chromosome 17p. In two cases overexpression of the p53 oncoprotein of the spindle cell component showed a higher degree of staining than that of the carcinoma component; LOH was identified in both carcinoma and sarcomatous components in one case, while in contrast, another case showed LOH in the sarcomatous component only. Mutations were clearly detected in two cases; one showed a CTT to CGT transversion in codon 194 of exon 6 in both components, whereas the other showed a CTG to CAG transversion in codon 265 of exon 8 in the sarcomatous component only. On the basis of these observations, it suggested that the sarcomatous component shows a higher frequency of p53 gene abnormalities in comparison to the carcinoma component. These results also suggested that the acquisition of malignant potential in the sarcomatous component, or the morphological alteration of carcinoma cells, is correlated with abnormalities associated with the p53 gene.

Pleomorphic (spindle/giant cell) carcinoma of the lung. A clinicopathologic correlation of 78 cases

BACKGROUND

The authors undertook this study to define the clinical and histologic characteristics of spindle and giant cell carcinomas of the lung and the survival and prognostic features of these tumors.

METHODS

Seventy-eight cases of pleomorphic (spindle and/or giant cell) carcinoma of the lung were studied by light microscopy and immunohistochemistry to establish clinical, gross, and histologic parameters. Follow-up information was obtained from contributing physicians and analyzed by statistical means to determine prognostically significant parameters.

RESULTS

The patient population consisted of 57 men and 21 women (male to female ratio, 2.7 to 1) between the ages of 35 and 83 years (mean, 62 years). Clinically, 58 patients (80%) presented with symptoms including thoracic pain, cough, and hemoptysis, whereas 14 (18%) were asymptomatic. At the time of diagnosis, 41% of the patients had clinical Stage I lesions, 6% Stage II lesions, 39% Stage III lesions, and 12% Stage IV lesions. Histologically, foci of squamous cell carcinoma were present in 8% of the tumors, large cell carcinoma in 25%, and adenocarcinoma in 45%. The remaining 22% of neoplasms were completely spindle and/or giant cell carcinomas. Spindle and giant cell carcinomas were found together in 38% of the patients. In the 69 patients for whom follow-up information was obtained, 53 (77%) died within 7 days to 6 years after diagnosis, with a 23-month mean survival (median, 10 months) (Kaplan-Meier method). There was a significant shortening of survival for patients with tumor size greater than 5 cm, clinical stage greater than 1, and lymph node involvement. The presence of nodal metastases was the most significant single prognostic factor, whereas the presence of squamous or adenocarcinomatous differentiation did not have an impact on length of survival.

CONCLUSIONS

The frequency with which spindle and giant cell carcinomas are found together, their frequent association with other histologic subtypes of lung carcinoma, and the similar clinicopathologic features of these tumors suggest that they are best regarded as one type of lung cancer called pleomorphic carcinoma.

Undifferentiated spindle cell carcinoma of the gallbladder: a clinicopathologic, immunohistochemical, and flow cytometric study of 11 cases

Eleven primary spindle cell carcinomas (SpCCs) of the gallbladder are reported. They occurred in eight women and three men ranging in age from 59 to 80 years (mean age, 66.5 years). Histologically, the tumors showed interlacing bundles of atypical spindle cells with eosinophilic cytoplasm, oval to elongated nuclei, and conspicuous nucleoli. Eight SpCCs contained tiny foci of neoplastic glands similar to those seen in adenocarcinoma, and two of these cases also had small foci of neoplastic squamous epithelium. A gradual transition between the squamous cell carcinoma and the spindle cell component was observed in one tumor. Immunohistochemically, all SpCCs were positive for at least one of the epithelial markers (epithelial membrane antigen, nine cases; AE1/AE3, nine cases; carcinoembryonic antigen, three cases; and EAB 903, one case), and the tumor cells also were immunoreactive to mesenchymal marker (vimentin, eight cases), muscle markers (alpha-smooth muscle actin, one case; desmin, one case), and histiocytic marker (HAM 56, one case). Abnormalities in tumor suppressor gene p53 expression also were found in two of the 11 SpCC cases using monoclonal antibody PAb 1801. In six cases for which data were available flow cytometry revealed aneuploidy in three SpCCs (50%). The survival curve of the SpCC cases (mean survival, 9 months) was less favorable than that of 224 cases of adenocarcinoma of the gallbladder (mean survival, 81 months) (P = .0011). These results indicate that SpCC of the gallbladder is an epithelial tumor with sarcomatoid components and its prognosis is unfavorable.

Lung carcinoma with spindle cell components: sixteen cases examined by immunohistochemistry

Sixteen cases of lung carcinoma with spindle cell components were studied by conventional histochemistry and immunohistochemistry. The epithelial components were squamous cell carcinoma in six cases, adenocarcinoma in four, adenosquamous carcinoma in five, and large cell carcinoma in one. In every case sarcomatous areas were distinctly observed and, in general, neoplastic spindle cells proliferated in close proximity to the epithelial elements. Some of the histochemical procedures suggested mesenchymal features in the stroma of the exophytic portions of three cases, but heterogeneous elements, such as bone or striated muscle, were not observed. By immunohistochemical examination the epithelial elements showed positive reactions for keratin, epithelial membrane antigen, and/or carcinoembryonic antigen to a varying degree according to the histologic types. The spindle cell elements revealed a positive immunoreaction for keratin in all but one case. Epithelial membrane antigen was demonstrated in sarcomatous areas of only five cases and carcinoembryonic antigen was not expressed at all. In contrast, vimentin was distinctly demonstrated in sarcomatous areas of five cases, although other mesenchymal markers, such as desmin, actin, and myosin, were negative. These findings indicate that the spindle cell components in these 16 cases may represent mesenchymal features with partial or complete loss of epithelial features.