John R. Muhm

Screening for lung cancer. A critique of the Mayo Lung Project.

The National Cancer Institute of the United States recently sponsored three large‐scale, randomized controlled trials of screening for early lung cancer. The trials were conducted at the Johns Hopkins Medical Institutions, the Memorial Sloan‐Kettering Cancer Center, and the Mayo Clinic. Participants were middle‐aged and older men who were chronic heavy cigarette smokers and thus at high risk of developing lung cancer. Screening procedures were chest radiography and sputum cytology, the only screening tests of established value for detecting early stage, asymptomatic lung cancer. In the Hopkins and Memorial trials the study population was offered yearly chest radiography plus sputum cytology every 4 months. The control population was offered yearly chest radiography only. In these trials the addition of sputum cytology appeared to confer no lung cancer mortality rate advantage. The Mayo Clinic trial compared offering chest radiography and sputum cytology every 4 months to offering advice that the two tests be obtained once a year. This trial demonstrated significantly increased lung cancer detection, resectability, and survivorship in the group offered screening every 4 months compared with the control group. However, there was no significant difference in lung cancer mortality rate between the two groups. The statistical power of these trials was somewhat limited. Nevertheless, results do not justify recommending large‐scale radiologic or cytologic screening for early lung cancer at this time.

Diffuse malignant mesothelioma of pleura: Diagnosis and survival in 92 cases

Clinical, radiographic, surgical, and pathologic findings and survival in 92 patients with diffuse malignant mesothelioma (DMM) of the pleura who were examined at the Mayo Clinic between 1950 and 1980, were studied retrospectively. With the use of defined criteria and ordinary tissue stains, the 92 cases were classified into the following histologic subtypes: purely epithelial, 42 cases; mixed, 29 cases; and sarcomatous, 21 cases. Eight of the sarcomatous cases were desmoplastic. Median survivals were 12, 5, and 3 months for the patients in the epithelial, mixed, and sarcomatous groups, respectively. Survival was significantly longer for patients with epithelial DMM. Women survived longer than men but more often had epithelial DMM. Early disease manifested as multiple discrete pleural nodules, predominantly on the parietal pleura. However, nine patients had a dominant mass. Radiographic signs especially suggestive of DMM were nodular pleural thickening, irregular thickening of interlobar fissures, a dominant mass, or decreased volume of the affected hemithorax.

Accuracy of assessment of the extent of examination by experienced colonoscopists

One hundred colonoscopies were done. The colonoscopist noted whether the cecum had been intubated as well as the markers used to make this determination. With the colonoscope in position at maximum penetration, a radiologist independently determined its position using fluoroscopy, with a contrast agent delivered through the colonoscope. The cecum was entered in 86 of 100 cases. The tip of the colonoscope was at the level of the ileocecal valve in nine additional cases; the colonoscopist judged that the cecum was well seen in five of these nine. In one case, the colonoscopist overestimated the extent of the examination when transillumination in the right lower quadrant was the only confirming marker. When the more reliable markers (ileocecal valve, appendiceal orifice, converging indentations of the taenia coli in the cecal pole) were seen, no errors were made. Experienced colonoscopists are accurate in assessing the extent of colonoscopy and fluoroscopic confirmation is not routinely needed. When reliable markers are not seen during the examination, a barium enema, preferably with air contrast, should be done.

Radiographic manifestations of pulmonary histoplasmosis: a 10-year review.

Of 269 patients with histoplasmosis, 259 had radiographic manifestations of the disease. Of these, 217 showed multiple or solitary nodules, 28 infiltrates, 25 adenopathy, 5 fibrosing mediastinitis, 5 cavitation (3 infiltrates, 2 nodules), and 1 pleural effusion.

Upper Lobe Pulmonary Fibrosis Associated With High-Dose Chemotherapy Containing BCNU for Bone Marrow Transplantation

Upper lobe fibrotic lung disease is most often associated with sarcoidosis, Langerhans cell histiocytosis, silicosis, and other pneumoconioses but is usually not associated with drug-induced lung disease. Carmustine (BCNU) is a chemotherapeutic agent known to cause pulmonary toxicity. The radiographic pattern is usually diffuse bilateral lung disease predominantly in the lung bases. Upper lobe fibrotic disease associated with BCNU has been reported to occur in children treated for central nervous system gliomas. Often the lung disease occurs years after the exposure. Despite the widespread use of BCNU in the treatment of malignancy in adults, to our knowledge, the complication of upper lobe fibrotic disease has not been reported in adults. We describe a patient who presented with pneumothorax and bilateral upper lobe pulmonary fibrosis that we believe was due to BCNU given for bone marrow transplantation as part of therapy for breast cancer. Bilateral upper lobe pulmonary fibrosis can be associated with chemotherapeutic drugs.

Computed tomography of benign mature teratomas of the mediastinum

The computed tomography (CT) findings of five benign, mature teratomas of the anterior mediastinum collected during a ten-year period are described, and their case histories are reviewed. Three of the five were primarily cystic, with only small soft tissue components. One of the five contained equal cystic and solid elements. All cysts had a higher attenuation than water. Three tumors contained small foci of dense calcification or ossification. Only two contained fat. Computed tomography accurately predicted the presence of adherence to adjacent structures in all five. Four of five patients were less than 22 years of age, and benign teratoma of the mediastinum was not a common neoplasm at any age. The origin and pathology of germ cell tumors of the mediastinum are briefly reviewed.

Quality-of-service improvements from coupling a digital chest unit with integrated speech recognition, information, and Picture Archiving and Communications Systems

Speech recognition reporting for chest examinations was introduced and tightly integrated with a Radiology Information System (RIS) and a Picture Archiving and Communications System (PACS). A feature of this integration was the unique one-to-one coupling of the workstation displayed case and the reporting via speech recognition for thatand only that particular examination and patient. The utility of the resulting, wholly integrated electronic environment was then compared with that of the previous analog chest unit and dedicated wet processor, with reporting of hard copy examinations by direct dictation to a typist. Improvements in quality of service in comparison to the previous work environment include (1) immediate release of the patient, (2) decreased rate of repeat radiographs, (3) improved image quality, (4) decreased time for the examination to be available for interpretation, (5) automatic hanging of current and previous images, (6) ad-hoc availability of images, (7) capability of the radiologist to immediately review and correct the transcribed report, (8) decreased time for clinicians to view results, and (9) increased capacity of examinations per room.

The Enhancing Rim: A New Sign of a Benign Pulmonary Nodule

OBJECTIVE To describe a new radiological sign, the enhancing rim sign, that indicates that a solitary pulmonary nodule is benign rather than malignant. PATIENTS AND METHODS Sixteen adult patients underwent computed tomographic (CT) evaluation with intravenous contrast enhancement of an indeterminate solitary pulmonary nodule between May 25, 2000, and March 21, 2002, at the Mayo Clinic in Scottsdale, Ariz. In each patient, we identified a rim of enhancing soft tissue at the periphery of a solitary pulmonary nodule; this rim surrounds a homogeneous, lower-density central portion of the nodule. Surgical or biopsy specimens from 6 patients and clinical data from 10 patients were evaluated to determine whether the nodules with the enhancing rims were benign or malignant. RESULTS Pulmonary nodules in 6 patients were diagnosed as benign after histological evaluations of tissue obtained by surgical resection (3 patients), bronchoscopic biopsy (1 patient), and CT-guided needle biopsy (3 patients) (1 patient had a needle biopsy and wedge resection). In another 10 patients, pulmonary nodules were diagnosed as benign during clinical follow-up (range, 2-24 months; median, 11 months): in 1 patient, the nodule disappeared; in 1 patient, the nodules size was stable; in 3 patients, the nodules size decreased; and in 5 patients, no further radiological studies were performed, but no symptoms or signs of pulmonary disease were present during follow-up. Coccidioides immitis spherules were identified in 2 surgical specimens and in 1 CT-guided biopsy specimen. Serologic results for C immitis were positive for 3 patients: 1 at the time of lobectomy and 2 during clinical follow-up. CONCLUSION The enhancing rim sign, seen on chest CT with intravenous contrast enhancement of a solitary pulmonary nodule, has been useful to distinguish some benign pulmonary nodules from malignant pulmonary nodules.

Mediastinal masses. Clues to interpretation of radiologic studies

The best approach to evaluation of a mediastinal mass begins with a history and a physical examination that are oriented toward discovery of evidence of compression or obstruction to any of the mediastinal organs. Currently, the most efficient radiographic approach, after the plain chest roentgenogram, is computed tomography of the thorax, supplemented as needed by selected plain tomograms or a barium swallow examination. Unless the mass is definitely a benign lesion of no consequence, such as a pericardial fat pad, thoracotomy by an experienced thoracic surgeon is usually necessary to make a specific diagnosis and excision is performed if possible.

Nitrofurantoin-Induced Granulomatous Interstitial Pneumonia

Nitrofurantoin-induced lung toxicity is relatively common, but rare histologic patterns sometimes occur that may make diagnosis difficult. We present the case of a 69-year-old woman taking prophylactic nitrofurantoin for urinary tract infections, who developed granulomatous interstitial pneumonia. She improved with cessation of nitrofurantoin, without other therapy. To our knowledge, this is the fourth reported case of granulomatous interstitial pneumonia associated with nitrofurantoin, and the first to show complete resolution with cessation of the drug alone, without steroids. It is important to recognize that idiosyncratic reactions to nitrofurantoin can produce a wide spectrum of histologic patterns. Of these patterns, granulomatous interstitial pneumonia is a rarely evidenced manifestation (possibly because few cases undergo a confirmatory lung biopsy). Recognition of granulomatous interstitial pneumonia as a manifestation of nitrofurantoin toxicity can aid in early identification of the reaction and prompt withdrawal of the drug, both of which are essential to prevent long-term complications.