Endotracheal/endobronchial metastases : clinicopathologic study with special reference to developmental modes

BACKGROUND: Endotracheal/endobronchial metastases (EEMs) from nonpulmonary neoplasms are rare. However, their definition and developmental modes have not yet been fully elucidated. METHODS: EEMs were defined as documented nonpulmonary neoplasms metastatic to the subsegmental or more proximal central bronchus, in a bronchoscopically visible range. The clinical and pathologic features of 16 cases were reviewed, with special emphasis on the developmental modes based on five criteria: location in the tracheobronchial tree, number of lesions, laterality of lesions, depth of lesions, and relationship with the associated bronchus. RESULTS: The developmental modes were proposed on the basis of the above five criteria as follows: type I, direct metastasis to the bronchus; type II, bronchial invasion by a parenchymal lesion; type III, bronchial invasion by mediastinal or hilar lymph node metastasis; and type IV, peripheral lesions extended along the proximal bronchus. Primary tumors included colorectal in six patients, breast in three patients, uterus in two patients, osteosarcoma of the bone in two patients, and maxillary, larynx, and parotid carcinoma in one patient each, respectively. The mean recurrence interval was 65.3 months. The developmental modes were as follows: type I, five patients; type II, one patient; type III, four patients; and type IV, nine patients. Three patients underwent surgical resection. One patient has remained well for 5 years after operation. Median and mean survival times were 9 months and 15.5 months, respectively. CONCLUSION: The mean recurrence interval was long at 65.3 months, but the mean survival time was short at 15.5 months. Type I accounted for only 5 of 16 patients. Type II was found in only one patient. It is thought that this type is a rare form. Type IV affected nine patients. Treatment plans must be individualized, because in some cases, long-term survival can be expected.     

Vasoactive peptides in the lung, with special reference to vasoactive intestinal peptide

Numerous biologically active peptides are present in normal lung. Some of these, like vasoactive intestinal peptide (VIP) and substance P, are neuropeptides that may function as neurotransmitters or neuromodulators. The activities of lung peptides include relaxation or contraction of airway and pulmonary vascular smooth muscle, modification of bronchial water and mucus secretion, and stimulation of adenylate cyclase activity. Much remains to be learned about active peptides in the lung: their full identities, their localization, their physiologic roles, and their participation in disease processes. One of these peptides, VIP, widely distributed in other organ systems, may mediate the nonadrenergic relaxation of airways and pulmonary vessels. It may also regulate bronchial secretion and, through its promotion of cyclic adenosine monophosphate accumulation in the lung, may modulate the immunologic release of mediators from mast cells.     

Two cases of lung infection due to Mycobacterium shimoidei, with special reference to bacteriological investigation

Mycobacterium shimoidei (Tsukamura 1982) is an uncommon but widely distributed pathogen usually isolated from respiratory specimens. We report two cases of lung disease due to M. shimoidei and the associated bacteriological results. A 45-year-old man (Case 1) admitted to National Hospital Organization (NHO) Miyagi Hospital, a 75-year-old man (Case 2) admitted to NHO Higashi-Hiroshima Medical Center were found in initial chest X-ray and thoracic computed tomography (CT) to have a tuberculosis-like cavity in the left apex (Case 1) and the right apex (Case 2). In Case 1, the patient was treated with isoniazid and rifampicin for one month and lesions showed a partial response. In Case 2, the patient responded favorably with rifampicin, ethambutol, streptomycin, and clarithromycin therapy. Mycobacteria were repeatedly detected in smear and culture from sputum specimens in both patients. Isolates were nonphotochromogenic and rough. Isolated colonies developed after two to three weeks on 2% Ogawa egg medium. Organisms grew on 2% Ogawa egg medium at 30, 37, 42, and 45 degrees C, but not 25 degrees C. Both organisms were susceptible to 500 microg of p-nitrobenzoate per mL and 5mg of sodium chloride per mL. Isolates were negative for niacin accumulation, nitrate reduction, semiquantitative catalase, 68 degrees C catalase, 3-day aryl-sulfatase, iron uptake, and MPB64 antigen production, but positive for Tween 80 hydrolysis (5 and 10 days), acid phosphatase, and pyrazinamidase. Isolates had typical uv-HPLC chromatograms similar to M. shimoidei, demonstrating triple-peak clusters with peaks in the early cluster. 16S rRNA gene sequencing showed isolates to be consistent with Mycobacterium shimoidei. Based on composite characterization, isolates were identified as M. shimoidei. This is, to our knowledge, the third case of M. shimoidei infection reported in Japan.