Basaloid squamous cell carcinoma of the lung, an uncommon subtype of non-small cell carcinomas was introduced as a distinct entity in the recently revised World Health Organization (WHO) classification of lung tumours. This rare tumour most commonly develops in males older than 60 years. We report a 23-years-old female patient with basaloid squamous cell carcinoma of the lung who was stage IIB post-operatively. The patient is still alive and healthy 18 months after the operation. This is one of the youngest patient reported with this rare type of tumour.

Basaloid squamous-cell carcinoma of the lung in a young woman.Int J Clin Oncol. 2006 Feb;11(1):66-8.

We report a rare case of basaloid squamous cell carcinoma of the lung in a young Japanese woman. An 18-year-old woman presented with productive cough. Chest radiogram and computed tomography (CT) revealed a tumor in the left hilum accompanied by partial atelectasis of the left upper lobe and pleural effusion. Transbronchial fine-needle aspiration cytology supported a tentative diagnosis of primary squamous-cell carcinoma of the lung. The clinical stage was T4N2M1, with multiple bone metastases. Despite a transient response to chemotherapy consisting of carboplatin and paclitaxel, the patient died because of tumor progression 2 months after the start of the chemotherapy. Necropsy established the diagnosis of basaloid squamous-cell carcinoma of the lung. Immunohistochemical studies of the necropsy specimen indicated that the tumor was positive for keratin, vimentin, and S100, and negative for chromogranin A, cytokeratin CAM5.2, and bcl-2. Besides the rarity of the disease itself, the present case seemed to have additional uniqueness in that the patient was 18 years old and female. This is the youngest patient with a case of basaloid squamous cell carcinoma of the lung ever reported.

Basaloid carcinoma of the lung.Jpn J Thorac Cardiovasc Surg. 2005 May;53(5):263-5.

Basaloid carcinoma (BC) of the lung is a rare and an aggressive subtype of non small cell lung cancer. We report a patient with preoperative cytologic features of either lung BC or squamous cell carcinoma. Finally, the tumor was diagnosed as a pure BC of the lung by the immunohistological findings. The patient's recovery was uneventful and remained asymptomatic without recurrence 18 months after surgery. However, considering to the biological behavior of BC, regular follow-up for this patient will be required.

Basaloid carcinoma of the lung: a really dismal histologic variant?Ann Thorac Surg. 2003 Dec;76(6):1833-7.

BACKGROUND: Basaloid carcinoma of the lung has been reported as an uncommon and highly aggressive form of nonsmall cell lung cancers. Even in stage I and II of basaloid carcinoma, a 5-year survival rate of only 15% has been reported and it has been suggested that different treatment modalities for basaloid carcinoma should be considered. The aim of this study was to determine the prognostic implications of a basaloid carcinoma of the lung. METHODS: This study included a series of 291 surgically resected lung tumors, which were originally diagnosed as a poorly or undifferentiated carcinoma, a small cell carcinoma, or an atypical carcinoid. Of these, 35 basaloid carcinoma patients were identified and compared with 167 poorly differentiated squamous cell carcinoma (PDSC) patients in terms of the preoperative clinical data, the procedure performed, and the survival outcome. RESULTS: The overall incidence of basaloid carcinoma was 4.8%. The actuarial 5-year survival rate was 40.6% in patients with PDSC and 36.5% in those with basaloid carcinoma (p = 0.86). In stage I and II patients, the actuarial 5-year survival rate was 53.9% in the PDSC group and 57.2% in the basaloid group (p = 0.97). There were no differences in the recurrence rate and the relapse pattern (p = 0.584). Cox's proportional hazards model revealed that an age equal to 60 years old (hazard ratio 2.179, p = 0.000) and an advanced stage (hazard ratio 2.264, p = 0.000) were the risk factors for postoperative survival in both groups. CONCLUSIONS: Basaloid carcinoma of the lung does not have a worse prognosis than the other nonsmall cell lung cancers. Although it is obvious that a basaloid carcinoma is a unique histologic entity, it does not require a different treatment modality due to the similar clinical behavior with other nonsmall cell lung cancers.

Basaloid carcinoma, a rare primary lung neoplasm: report of a case and review of the literature.Lung Cancer. 2002 Mar;35(3):335-8.

Basaloid carcinoma of the lung is a rare primary neoplasm, first described in 1992. Basaloid carcinoma is an aggressive subtype of Non small cell lung cancer, with poor 5-year survival, even in stage I and II resected tumors. Differential diagnosis from small cell, Neuroendocrine large cell and poorly differentiated squamous cell carcinoma is difficult to be made. We report a patient with lung basaloid carcinoma, initially diagnosed and treated as small cell carcinoma. Thoracotomy and resection of the tumor following chemotherapy, established the correct diagnosis.

Basaloid-squamous cell carcinoma of the bronchus. Report of a case with review of the literature.Arch Pathol Lab Med. 1995 Dec;119(12):1167-70.

Basaloid-squamous cell carcinoma (BSCC) is a variant of squamous cell carcinoma with biphasic basaloid and squamous features. Recognition of BSCC is important because this lesion can be confused with less aggressive lesions, such as adenoid cystic carcinoma. BSCC is typically detected at an advanced stage in smokers, alcoholics, and older individuals; adenoid cystic carcinoma is not associated with smoking or alcohol, and it typically occurs in younger individuals. Approximately 88 cases of BSCC in the upper aerodigestive tract have been recorded since its first description in 1986. We report one case of endobronchial BSCC. Cytologically, both squamous and basaloid features were identified, including elongated, irregular, globular, extracellular, hyaline material. Immunohistochemical studies showed two distinct populations of cells: the squamous component, positive for cytokeratin (AE1 + AE3) and negative for smooth-muscle actin, epithelial membrane antigen, S100 protein, and type IV collagen; and the basaloid component, positive for all of the above markers, with minimal staining for cytokeratin (AE1 + AE3). The electron microscopy demonstrated desmosomes in the squamous component and replication of the basal lamina in the basaloid component. We conclude that BSCC of the bronchus is similar to BSCC in the upper aerodigestive tract and should be regarded as a distinct entity.

Basal cell (basaloid) carcinoma of the bronchi.Rev Mal Respir. 1995;12(6):601-7.

Basal cell carcinomas (BCC) have been described in various locations such as skin, anal canal, tongue, larynx and recently the lungs. These tumors seem to have a poor prognosis. A series of 115 surgically resected lung tumors, previously classified as poorly or undifferentiated carcinoma was retrospectively reviewed. From those 37 cases were reclassified as BCC and were compared in terms of clinical features and survival with 40 cases reclassified as poorly differentiated squamous cell carcinoma (PDSC) of the lung. There was no difference between the groups with respect to age, clinical presentation, pattern of relapse and cause of death. Median and overall survival were different between the 2 groups, especially for stage I and II patients: 5 years actuarial survival in BCC was 15% and in PDSC 47% p = 0.009). There was also a difference in survival when we studied the patients alive 4 weeks after surgery (p = 0.04). This subset of non small cell lung cancer (NSCLC) has a worse prognosis than other NSCLC.

Basal cell (basaloid) carcinoma of the lung: a new morphologic and phenotypic entity with separate prognostic significance. Hum Pathol. 1992 Sep;23(9):993-1003.

On review of 115 poorly or undifferentiated lung cancers from 671 lung tumors resected over a 7-year period, we have found 38 cases of basaloid carcinoma. The cardinal histopathologic features distinguishing this tumor from other non-small cell lung cancers are a lobular growth pattern of small cells with moderately hyperchromatic nuclei, with no prominent nucleoli, and with scant cytoplasm, a high mitotic rate, and peripheral palisading. Basaloid carcinoma was present in a pure form in 19 cases and the other 19 tumors were of a mixed, but prominent, basaloid type associated with squamous cell carcinoma, large cell carcinoma, or adenocarcinoma. The immunophenotype of basaloid cancers was close to that of basal bronchial epithelial cells, with a low level of expression of low molecular weight cytokeratins. Staining for neuroendocrine markers was infrequent and inconsistent. Ultrastructural study showed an absence of neurosecretory granules and the presence of some squamous and/or glandular differentiation. This morphologic and immunologic phenotype suggests that basaloid carcinoma is derived from a pluripotent reserve cell or a basal bronchial epithelial stem cell. This unique histologic form of lung tumor has a poor prognosis, with a median survival rate of 22 months for stage I and II disease. This justifies classification of basaloid carcinoma as a distinct form of lung cancer, separate from small cell lung carcinoma.