How much brushing is enough for the diagnosis of lung tumors?

Guidelines for diagnostic flexible bronchoscopy in adults: Joint Indian Chest Society/National College of chest physicians (I)/Indian association for bronchology recommendations

Flexible bronchoscopy (FB) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. However, bronchoscopy practices vary widely across India and worldwide. The three major respiratory organizations of the country supported a national-level expert group that formulated a comprehensive guideline document for FB based on a detailed appraisal of available evidence. These guidelines are an attempt to provide the bronchoscopist with the most scientifically sound as well as practical approach of bronchoscopy. It involved framing appropriate questions, review and critical appraisal of the relevant literature and reaching a recommendation by the expert groups. The guidelines cover major areas in basic bronchoscopy including (but not limited to), indications for procedure, patient preparation, various sampling procedures, bronchoscopy in the ICU setting, equipment care, and training issues. The target audience is respiratory physicians working in India and well as other parts of the world. It is hoped that this document would serve as a complete reference guide for all pulmonary physicians performing or desiring to learn the technique of flexible bronchoscopy.

Diagnostic flexible bronchoscopy and accessory techniques

We reviewed the most important diagnostic procedures implemented by means of flexible bronchoscopy, including bronchoalveolar lavage, bronchial brushing and biopsy, transbronchial lung biopsy and transbronchial needle aspiration. We reviewed the tools, techniques and potential complications of this examination.

Bronchoscopy and needle biopsy techniques for diagnosis and staging of lung cancer

Lung cancer is the leading cause of cancer deaths in the United States. The individual therapeutic approach and prognosis depends on accurate diagnosis and staging. Flexible bronchoscopy (FB) and transthoracic needle biopsy (TNB) are the most widely used techniques for this purpose. This article provides a critical overview of indications, diagnostic yield, and limitations of bronchoscopy and TNB in the diagnosis of lung cancer.

Value and accuracy of cytology in addition to histology in the diagnosis of lung cancer at flexible bronchoscopy

There is still disagreement as to the value and reliability of wash and brush cytology, in comparison with histology, for the diagnosis of malignancy at flexible bronchoscopy. The present study compares the yield and concordance of findings from the two modalities for visible tumours at flexible bronchoscopy. A single-centre study of 514 consecutive flexible bronchoscopy procedures, in which a lesion suspicious of cancer was seen and bronchial wash cytology, brush cytology and forceps biopsy samples were taken. All equivocal or suspicious results were taken as negative. An overall yield of 89.3% was achieved using a combination of all three tests. This was greater for endobronchial than submucosal (95% vs. 86%) tumours. Cytology alone diagnosed 17.7% of cases. Use of all three modalities allowed tumours to be differentiated between small and non-small cell types in all but 5/459 positive cases (98.9%). There were only 3/313 cases in which there was a difference in cell type (small cell vs. non-small cell) between the two modalities. We conclude that wash and brush cytology are valuable tools, in addition to forceps biopsy, at flexible bronchoscopy. All three tests should be performed routinely in cases of suspected malignancy.

Volatile organic compounds in breath as markers of lung cancer: a cross-sectional study

BACKGROUND

Many volatile organic compounds (VOCs), principally alkanes and benzene derivatives, have been identified in breath from patients with lung cancer. We investigated whether a combination of VOCs could identify such patients.

METHODS

We collected breath samples from 108 patients with an abnormal chest radiograph who were scheduled for bronchoscopy. The samples were collected with a portable apparatus, then assayed by gas chromatography and mass spectroscopy. The alveolar gradient of each breath VOC, the difference between the amount in breath and in air, was calculated. Forward stepwise discriminant analysis was used to identify VOCs that discriminated between patients with and without lung cancer.

FINDINGS

Lung cancer was confirmed histologically in 60 patients. A combination of 22 breath VOCs, predominantly alkanes, alkane derivatives, and benzene derivatives, discriminated between patients with and without lung cancer, regardless of stage (all p<0.0003). For stage 1 lung cancer, the 22 VOCs had 100% sensitivity and 81.3% specificity. Cross-validation of the combination correctly predicted the diagnosis in 71.7% patients with lung cancer and 66.7% of those without lung cancer.

INTERPRETATION

In patients with an abnormal chest radiograph, a combination of 22 VOCs in breath samples distinguished between patients with and without lung cancer. Prospective studies are needed to confirm the usefulness of breath VOCs for detecting lung cancer in the general population.

The incidence and detection of HPV in the upper aerodigestive tract using brush and biopsy techniques

The association between human papillomavirus (HPV) and squamous carcinoma is well established. In the polymerase chain reaction (PCR) we have an effective technique for detecting small quantities of viral DNA, but the assay requires tissue taken at endoscopy to reveal the presence or absence of HPV. Brushings have been used effectively elsewhere in the body to obtain cytological material. This study set out to ascertain if sufficient viral DNA could be obtained, using a laryngeal brushing and the PCR, to detect the presence or absence of HPV. Six patients with squamous carcinoma of the larynx and seven controls who were having laryngoscopy for other reasons underwent laryngeal biopsy. In addition, in the patients with carcinoma, biopsies were taken at the tumour margins and brushings from both sites. The samples were tested for the presence of HPV types 6, 11, 16, 18 and 31 by means of the PCR. The distribution of HPV types was as expected in the biopsy specimens, but only one brushing detected any HPV type at all. We conclude that laryngeal brushing is an inadequate technique for assessing the presence of HPV in the larynx.

Multiple brushings with immediate Riu's stain via flexible fibreoptic bronchoscopy without fluoroscopic guidance in the diagnosis of peripheral pulmonary tumours

BACKGROUND

Accurate diagnosis of peripheral pulmonary lesions usually relies on fluoroscopic guided procedures. As fluoroscopy is not routinely available in many respiratory units, an approach not using fluoroscopy but with a high diagnostic yield is highly desirable.

METHODS

Immediate cytological examination of multiple brushings using Riu's stain, a modified Wright's stain, was performed in 38 patients with peripheral pulmonary lesions not visible at bronchoscopy. The results were compared with the final diagnoses determined by histological examination or subsequent Papanicolaou staining of cytological specimens and clinical course.

RESULTS

Of the 38 patients 29 were subsequently confirmed to have a malignant tumour. Our method provided a diagnosis of malignancy in 86% of these lesions. The accuracy (91%) and sensitivity (88%) were higher for lesions > 3 cm in diameter than for those of diameter < or = 3 cm (87% and 83%). There were no false positive results. The 29 lesions correctly diagnosed as malignant by Riu's stain required significantly fewer brushings (mean (SD) 3 (2)) than the nine benign lesions (5 (4)).

CONCLUSIONS

This technique provides a high diagnostic yield, avoids the need for fluoroscopy, and is probably safer than percutaneous biopsy.