Wah K. Lam

Lymphoepithelioma-like carcinoma of the lung

Abstract:  Lymphoepithelioma‐like carcinoma (LELC) of the lung was first reported in 1987. In the past two decades, there have been just more than 150 cases reported in the literature. This uncommon but distinct form of non‐small cell lung carcinoma has a predilection for young non‐smoking Asians, without gender distinction. Histologically, it is indistinguishable from undifferentiated nasopharyngeal carcinoma. The carcinogenic role of latent Epstein–Barr virus infection in causing LELC of the lung has been evident almost exclusively in Asians compared with Caucasians. Among the reported cases, more than half were in early resectable stages (I or II) and there was a tendency for peribronchovascular spread with vascular encasement in advanced diseases. In order to establish the diagnosis of LELC of the lung, both nasopharyngeal carcinoma and lymphoma have to be excluded by endoscopic biopsy (with or without magnetic resonance imaging of the nasopharynx) and immunohistochemical staining of the biopsy samples. The mainstay of treatment for early‐stage disease is curative surgical resection, whereas multimodality treatment (surgery, chemotherapy, radiotherapy) has been adopted in advanced or metastatic diseases. The overall survival is more favourable in LELC of the lung compared with non‐LELC type of non‐small cell lung carcinoma. Future collaborative studies especially on optimizing treatment for this uncommon malignancy are clearly warranted.

Regression of bilateral bronchiectasis with inhaled steroid therapy.

Abstract: Bronchiectasis is defined as pathological and permanent dilatation of the bronchial tree. Affected patients suffer from chronic sputum production and usually slowly progressive airway destruction as a result of continued airway infection and inflammation. Regression of bilateral bronchiectasis has never been reported in the English literature. We report the case of a 60‐year‐old woman with longstanding progressive idiopathic bilateral bronchiectasis whose respiratory symptoms, including sputum, rapidly disappeared after commencement of inhaled budesonide. Repeat computed tomography assessment 40 months after commencement of inhaled steroid therapy, showed partial regression of bronchial dilation and resolution of small airways sepsis. In the absence of other possible explanations for the partial resolution of the bronchiectasis, the present case suggests a possible benefit of inhaled steroid therapy in bronchiectasis.

Diagnostic yield of bronchoscopic sampling methods in bronchial carcinoma.

The aim was to study the yield of malignant or suspicious cells from bronchoalveolar lavage (BAL), endobronchial biopsy (BX) and endobronchial brushing (BR) specimens obtained at bronchoscopy.

Extrapulmonary presentation of asymptomatic pulmonary lymphangioleiomyomatosis

Abstract:  Lymphangioleiomyomatosis (LAM) is a rare parenchymal lung disease, which affects young women of childbearing age and is characterized pathologically by proliferation of interstitial smooth muscle and formation of cysts in the lung. While LAM is usually predominantly a respiratory disorder, it can also initially involve other extrapulmonary organs. We report the case of a 35‐year‐old Chinese woman, who presented with a 4‐week history of left thigh swelling which was found to be secondary to compression of pelvic veins by a mass lesion. The latter was found histologically to show LAM. Despite the patient being asymptomatic and displaying normal lung function, a thoracic high resolution CT scan showed typical features of early LAM. This case further illustrates that LAM can have multisystem involvement, and demonstrates the importance of being aware of the diagnosis in cases presenting with extrapulmonary manifestation, in order that patients are diagnosed and managed appropriately.

Detection and evaluation of p53 intron 2 polymorphism in lung carcinomas in Hong Kong

A polymorphism in intron 2 of the p53 gene, which gives rise to 2 alleles, A1 and A2, was analyzed by polymerase chain reaction‐single strand conformation polymorphism (PCR‐SSCP) and direct DNA‐sequencing techniques. The distribution of this allele in the peripheral blood in the Chinese population comprising 27 healthy individuals, 30 bronchiectasis patients, 34 non‐small‐cell lung cancer (NSCLC) patients and 27 SCLC patients was analyzed. The genotypic distributions for this marker were significantly different between the blood of healthy individuals and SCLC patients. There was no significant difference between genotypes of Caucasians and Chinese. Tumors, normal lungs and peripheral blood of 83 adenocarcinoma and 10 squamous cell carcinoma patients were also studied. There was a significant difference in the distribution of the genotypes detected in tumor tissues vs. blood of adenocarcinoma patients. The frequency of detection of the A1/A1 genotype in the tumor tissues was increased in adenocarcinoma patients as compared with the blood of adenocarcinoma patients and was decreased in the blood of SCLC patients as compared with the blood of healthy individuals. Survival rates in Hong Kong adenocarcinoma patients with the A1/A1 genotype were lower than those in patients with A1/A2 and A2/A2 genotypes up to 30 months post‐operation. Point mutations were detected at the p53 intron 2 polymorphic locus in NSCLC specimens, with a mutation rate of 15.4% (8/52). All mutations were GC transversions. The significance of this instability in p53 intron 2 remains to be elucidated.

Capecitabine as Salvage Treatment for Lymphoepithelioma-Like Carcinoma of Lung

Lymphoepithelioma-like carcinoma (LELC) of lung has previously demonstrated good clinical response to 5-fluorouracil containing chemotherapy regimen, similar to the observation in undifferentiated nasopharyngeal carcinoma. Capecitabine, which is converted into active 5-fluorouracil within tumor cells, has been found effective in colorectal, breast, and recently nasopharyngeal carcinomas. We report our experience in five patients with advanced or metastatic LELC of lung who were treated with single agent capecitabine as salvage chemotherapy. The finding of disease control in three of five patients, especially with exceptionally durable stable disease (14.8 months) in one patient, suggests the potential clinical activity of capecitabine in LELC of lung. Future studies on capecitabine-containing chemotherapy regimens in LELC of lung are warranted.

Clinical value of ciliary assessment in bronchiectasis.

Although ciliary dysfunction and numerous ultrastructural defects have been described, and these could be etiologically important in the development of bronchiectasis, their correlation with relevant clinical parameters have not been systematically evaluated. We have prospectively evaluated the prevalence and clinical significance of ciliary beat frequency and ultrastructural defects of nasal respiratory mucosa obtained from 152 stable patients with idiopathic bronchiectasis (100F, 57.7±15.2 yrs) and 127 control subjects (58F, 56.0±24.2 yrs). Bronchiectasis patients had significantly slower ciliary beat frequency (p < 0.05), and a greater percent of patients had central and peripheral microtubular defects (OR 14.4, 95% CI 5.6-36.8), namely, extra peripheral microtubules, “9+1”, “8+2”, and compound cilia (p < 0.05), but not microtubular disarrangement, extra matrix or ciliary tail abnormalities (p > 0.05), than controls. Bronchiectasis patients also had a greater proportion of cilia with any ultrastructural microtubular defects, compound cilia, and ciliary tails than controls (p < 0.05). Ciliary beat frequency did not correlate with clinically relevant parameters (p > 0.05). However, the percent of cilia with central, but not peripheral, microtubular defects correlated with 24 h sputum volume (r = 0.40, p = 0.001, and r = −0.04, p = 0.70, respectively) and FEV1 (r = −0.24, p = 0.01, and r = 0.00, p =0.99 respectively). Our results strongly suggest a pathogenic role for central microtubular defects in the development of idiopathic bronchiectasis.

Bronchoscopy of Cetaceans

Bronchoscopy is a standard diagnostic and therapeutic procedure in respiratory medicine and has been performed on many animal species. Cetaceans suffer considerable morbidity and mortality from lower respiratory tract infections, and it is very difficult to sample lower respiratory tract secretions for microbiology and other analyses. We report our experience on performing fiberoptic bronchoscopy in three bottle-nosed dolphins (Tursiops truncatus) and one false killer whale (Pseudorca crassidens), which should help other clinicians in performing bronchoscopy in cetaceans.