PULMONARY BLASTOMAS: A DISTINCTIVE GROUP OF CARCINOSARCOMAS OF THE LUNG

Cure of Oligometastatic Classic Biphasic Pulmonary Blastoma Using Aggressive Tri-modality Treatment: Case Series and Review of the Literature

Pulmonary blastoma is a rare lung cancer classified into three subtypes: classic biphasic pulmonary blastoma (CBPB), well-differentiated fetal adenocarcinoma (WDFA), and pleuropulmonary blastoma (PPB) of childhood. Compared to the other subtypes, CPPB is an aggressive tumor with an overall five-year survival of 16% across all stages. We present two cases of biopsy-proven metastatic CBPB, who have been disease-free for over 10 years since treatment completion. Both patients were treated with surgery to the primary tumor followed by an adjuvant cisplatin-based chemotherapy for four cycles and thoracic radiation. One patient relapsed shortly after the completion of thoracic radiation with brain metastases and underwent craniotomy, gamma knife radiosurgery (GKRS), and whole brain radiation therapy. The other patient presented with synchronous pelvic metastases and underwent metastasectomy after the completion of chemotherapy but before the initiation of thoracic radiation. We review the literature regarding surgical, chemotherapeutic, and radiation treatment for patients with metastatic pulmonary blastoma. Based on our experience and review of the existing case reports, aggressive tri-modality treatment including surgery, chemotherapy with a cisplatin backbone, and a definitive treatment of oligometastatic lesions amenable to local therapy including resection or radiosurgery is reasonable to consider for medically fit patients with CBPB.

Use of multicolor spectral karyotyping in genetic analysis of pleuropulmonary blastoma

Pleuropulmonary blastoma (PPB) is a rare, malignant intrathoracic pediatric tumor. It arises from the lung, pleura, or mediastinum and its pathogenesis and relationship to other pediatric solid tumors is not well understood. In this study, a case of PPB in a 3-year-old girl was studied using a combination of molecular genetic methods and cytogenetics. Molecular analysis of the commonly encountered fusion translocation gene products of pediatric solid tumors failed to detect a rearrangement. Cytogenetic analysis, supplemented by multicolor spectral karyotyping (SKY), identified an unbalanced translocation between chromosomes 1 and X, resulting in additional copies of 1q, an extra copy of Xq, and loss of part of Xp. In addition, trisomy 8 was detected. The identification of new chromosomal alterations and confirmation of previously reported ones in this rare neoplasm helps to improve our understanding of its pathogenesis and association with other pediatric tumors.

Pleuropulmonary blastoma. The so-called pulmonary blastoma of childhood

The authors studied 11 pediatric intrathoracic neoplasms that share clinicopathologic features and constitute a specific tumor in children. These neoplasms were intrapulmonary, mediastinal, or pleural-based masses. A common histologic feature was the presence of small, primitive cells with blastematous qualities separated by an uncommitted stroma. Focal rhabdomyosarcomatous, chondrosarcomatous, and liposarcomatous differentiation was observed. Epithelial components had bland cytologic features and probably represented entrapped benign epithelium and/or mesothelium. The prognosis for these patients was grave; seven patients died of their disease 5 months to 2 years after diagnosis. Two patients have survived disease-free for 10 and 12 years after diagnosis. Two recent cases are alive 14 and 32 months after diagnosis. This neoplasm constitutes a distinct entity which has been reported in the literature as pulmonary blastoma in children. It differs from pulmonary blastoma in adults because of its variable anatomic location, primitive embryonic-like blastema and stroma, absence of a carcinomatous component, and potential for sarcomatous differentiation. The designation of pleuropulmonary blastoma is suggested by the authors for these intrathoracic neoplasms of childhood rather than pulmonary blastoma for histogenetic and anatomic reasons. The clinicopathologic features, immunophenotypic and ultrastructural characteristics, possible histogenesis, and differential diagnosis of these neoplasms from other thoracopulmonary tumors in children serve as the basis for this report.

Chemotherapy of pulmonary blastoma: a case report and review of the literature

Pulmonary blastoma is a rare lung tumor of uncertain histogenesis. Although surgery may be curative therapy for localized lesions, recurrent tumor has been resistant to various treatment modalities. We report a case of metastatic pulmonary blastoma that had a partial remission with combination chemotherapy. Suggestions are made for the treatment of localized and metastatic pulmonary blastoma.

Papillary carcinoid tumor of the lung

Carcinoid tumors of the lung have a wide histologic spectrum. The histologic differential diagnosis of papillary tumors in the lung generally does not include carcinoid. A carcinoid tumor that formed a discrete coin lesion on chest radiograph is presented in this report. On gross examination the center appeared and felt spongy. On microscopic examination delicate, compacted papillae were separated by a serpentine space continuous with air spaces at the periphery of the tumor. The papillae were each composed of a fibrovascular core, an undulating basement membrane separating stroma from epithelial cells, and cuboidal clear and dark cells that proved to be, respectively, healthy and degenerate cells of carcinoid tumor with neurosecretory granules. Upon the carcinoid cells, draped in the manner of an umbrella, were nonciliated, respiratory cells that proved to be Clara cells. The various histologic patterns of bronchopulmonary carcinoids and the differential diagnosis of papillary tumors within the lung are tabulated.

Nasal blastoma: a light and electron microscopic study

The first light and electron microscopic study of a nasal blastoma is reported. Analogous to a pulmonary blastoma, the tumor is composed of well-differentiated squamous and glandular epithelial elements surrounded by a spindle cell stroma. The spindle stromal cell is a myofibroblast. Eighteen months after complete surgical removal of the tumor and radiation therapy, the patient is clinically free of disease.

Pulmonary blastoma: an ultrastructural study with a brief review of literature and a discussion of pathogenesis

A pulmonary blastoma is reported in a 19-year-old black female. The light and electron microscopic characterics are described; they are found to be similar to those of the fetal lung prior to the fourth gestational month. Although the ultrastructural features do not favor any particular theory of histogenesis of this unique tumor, evidence for the commonly held theory that the tumor arises from pluipotential pulmonary blastema seems tenuous. A brief review of the literature disclosed 38 other similar cases. There was a male predominance with an average age of detection at 39 years. Sputum cytology was rarely positive. Among tumors larger than 5 cm in diameter, survival was usually less than 2 years. Metastases were present in approximately half of the cases.

Blastomatous tumors of the respiratory tract

Two cases of blastomatous tumors of the respiratory tract are presented. The first is a pulmonary blastoma of an 81-year-old man, diagnosed as adenocarcinoma by cytologic examination, the cells being exfoliated from the large carcinomatous component. The patient died 1 year after manifestation of the symptoms. The second case is a tumor that developed in the nasopharynx of a 62-year-old man. This is the first reported case of a nasopharyngeal blastoma that presented a histology comparable to that seen in the pulmonary tumor. The presence of a hamartomatous benign mesenchymal component raises histogenetic considerations as to whether this was an independent part of an otherwise malignant tumor or whether it was induced by the malignant growth. Following incomplete surgical treatment and postoperative radiation, no recurrence was observed during the next 8 months.

Pulmonary blastoma: report of two cases

Pulmonary blastoma is a rare primary malignancy of the lung originating from multipotential pulmonary blastema. Two cases of this tumor are reported emphasizing lack of correlation between the microscopic appearance and the clinical course. There are no specific clinical features that differentiate this tumor from the more common lung neoplasms. Surgical resection is the preferred treatment; the merits of radiotherapy and chemotherapy have not yet been established. Prognosis after adequate resection appears no better than for other pulmonary malignancies.

Pulmonary blastoma: a case report

Rao, K. M., Gupta, R. P., Das, P. B., John, S., and Walter, A. (1974).Thorax, 29, 138-141. Pulmonary blastoma. A case report of a pulmonary blastoma is presented. A tumour was suspected at surgery and on histological examination this proved to be a pulmonary blastoma. A short review of the histogenesis and methods of treatment is given.

Benign and malignant mixed tumours of the lung

Ten patients are presented with tumours complying with the criteria established by the World Health Organization for `mixed tumours of the lung'.

A slowly growing intrabronchial neoplasm indistinguishable from a pleomorphic adenoma (mixed salivary tumour) and a peripheral circumscribed tumour with most of the features of a chondromatous hamartoma were considered benign.

Of eight malignant neoplasms two were regarded as `pulmonary blastomas', one with a benign epithelial tubular component and the other with cytological evidence of malignancy in the tubular epithelium; in both, the stroma was `embryonic' and pleomorphic. Three tumours were considered carcinosarcomas with a mainly epidermoid epithelial component and a pleomorphic spindle-cell connective tissue component. In the remaining three tumours the malignant epithelial component showed mixed, viz., epidermoid, tubular, and a variety of undifferentiated appearances, while the `stroma' exhibited features seen in both blastomas and carcinosarcomas. These three neoplasms were considered `transitional'.

The spectrum of appearances encountered constitutes, in our opinion, a serious objection to the thesis that peripheral pulmonary blastomas and carcinosarcomas are distinct entities with a separate histogenesis. Exceptions were found to `blastomas' being peripheral and carcinosarcomas being central growths. A case is made for reclassification of the benign and malignant neoplasms included in the WHO group IX `mixed tumours of the lung'.

Pulmonary blastoma with diverse mesenchymal proliferation

Pulmonary blastomas are extremely rare subpleural tumours consisting of relatively well-differentiated branched tubular glands which resemble fetal lung tissue embedded in a malignant mesodermal stroma. The previous 13 established cases reported up to June 1969 are now supplemented by a fourteenth. The patient was a 32-year-old man who developed acute pain in the right chest followed by a haemorrhagic pleural effusion. At thoracotomy a yellowish-white necrotic and vascular tumour was located lying loosely in the fissure between the upper and the middle lobes. The histological appearance of the tumour was unusual in that the mesodermal element was very variable and in different areas simulated fibrosarcoma, leiomyosarcoma, lipomyxosarcoma, and malignant haemangiopericytoma. This diversity of mesodermal proliferation is best explained on the basis that the tumour has originated in an embryonic or pleuripotential type of mesenchyme, the site of which is probably in the periphery of the lung.

Pulmonary blastoma

A case of pulmonary blastoma is described in a man dying at the age of 50 from hepatic and cerebral metastases. Eleven previously reported cases are reviewed and the histogenesis is discussed. It is concluded that these rare tumours are a distinct form of pulmonary carcinosarcoma in which the epithelial element is an adenocarcinoma. It is this that gives it its characteristic and probably coincidental histological resemblance to foetal lung and the evidence for a blastomatous origin is regarded as insufficient.