- Email: [email protected]
Metastatic Squamous Cell Carcinoma of the Mediastinum With Unknown Primary Tumor
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FIGUHE 3. Microscopic appearance of' the lamina] surf~tce of the aberrant artery. The arte1y was composed of' elastic lam inae (hcmatm.y li neosin , original X 100).
findings of pulmonary artery occlusion or atherosclerosis . Since th e pulmonary ligam e nt artery is originally th e muscular type, and th e re is no evide nce to suggest that a muscular-type artery can transform into an elastic type, one cannot accept that th e pulmonary li gament arteries led to th e "creation " of ILS as desc ribed by Stocker and Malczac. ~ Th e re has b een som e confusion between chronic bronchiectasis with e nlarged bronchial arte ri es du e to infhmmation and ILS with abe rrant arteries. In this case, ILS with cystic appearance cou ld be easily confused with chronic bronchiectasis. Howeve r, as ILS is a congenital lesion but most cases of chron ic bronch iectasis without symptoms in chi ldh ood are acqui red , it must be conclud ed that the aberrant artery of ILS is th e e la stic type , and th e e nlarged bronchial artery of chronic bronchiectasis is of th e musc ular type . Ishida et aP have reported th at ILS in chi ldre n was classified into two groups, th e central type and th e p eripheral type, according to th e reco nstruction of th e bronchial tree in th e seq uestrated lu ng. Th ey claim ed that th e p eriph e ral type is th e tru e ILS , and th e central typ e is a mixture and a sequela of anoth e r disease such as bronchial atresia. Th e form e r type in segment 10 areas and aberrant arte ri es was elastic in histologi c nature . Th e la tter type in variable sites of th e les ion and arteries was muscular. It is suggested th at characteristics of an aberrant artery would b e use ful for th e definiti ve diagnosis of ILS to avoid confusion with other acquired diseases rega rdless of the anatomic appea rance or the pati e nt's age. Preoperative diagnosis of ILS is difficult. Savic et al 1 indicated that ILS was suspected or diagnosed preoperati vely in only 47 of 100 cases , whi le extralobar sequestration was preoperatively diagnosed in on ly 6 of 66 cases. Diffe rential diagnostic possibiliti es include bronchiectasis, lung abscess, e mpyema, lung neoplasm , congenital cystic adcnomatoid malformation , s taphylococcal pn eumoni a with pneumatocele formation , and congenital diaphragmatic hernia (Bochdalek's he rnia). Traditionally, the diagnosis of' ILS has been performed b y angiography to conflrm the aberrant arterial and venous drainage. In the reported case, aortography was not definitive . Diagnostic 938
flndin gs could not be obtained because all aberrant arteries were fin e pulmonmy ligam ent arteries. MRI, 5 CT scans v.rith contrast enhanceme nt as in this case, and spiral CT scans are useful in selected cases. In the CT v.rith con trast enhancement, small linear enhancements V\rith a tumor shadow in the left posterior basal segment near the descending aorta were obtain ed. Therefore, ILS was suspected. Surgical treatment is recommended for ILS , not only in symptomatic cases but also in asymptomatic C
2 :3
4 5 6
Savic B, Birtel F'J , Thol en \IV, et al. Lung sequestration: report of' seven cases and review of' .540 published cases. Thorax 1979; 34:96-101 Blesovsky A. Pulmonmy sequestration: a report of an unusual casP and a review of the literatmc. Thorax 1967; 22:351-357 II , Hayas hi A. Tntralobar sequestration in TIshida H, Iajikano children- a new concept from the form of bronchial tree in sequestrated lung. ippon Kyobu Geka Gakkai Zasshi 1992; 40:957-968 o f pulmomuy ligament s Stocker JT, Malezac liT. A tudy arteries: relationsh ip to intralobar pu lmona1y sequestration. Chest 1984; 86:61 1-615 monstration of blood supply to pulmonary Doyle A J. De sequestration by MR angiography. AJH Am J Hoentgenol j 992; 158:989-990 Haller JA, Golladay ES , Pickard LH, et a!. Surgical management of' lung bud anomalies: ol bar emphysema, bronchogenic cyst, cystic adenomatoid m
Metastatic Squamous Cell Carcinoma of the Mediastinum With Unknown Primary Tumor* Neri Blanco, MD; Daniel M. Kirgan , MD; and Alex G. Little, MD, FCCP
Although metastatic carcinoma from an unknown pdmary tumor is known to occur, the combination of squamous cell carcinoma histologic findings and a mediastinal location is quite unusual. The evaluation Selected Reports
of a case of a patient with a posterior mediastinal mass, eventually shown to be metastatic squamous cell carcinoma of the mediastinum with unknown primary tumor, is described herein. Resection of the lymph node mass was performed and was followed by chemoradiation for presumed lung cancer. (CHEST 1998; 114:938-940) Key words: mecliastinal mass; metastasis; squamous cell carcinoma; unknown prima1y tumor
M
etastatic squamous cell carcinoma with an unknown primary tumor is a rare occurrence reported only in a handful of case reports. 1•2 These reports usually describe patients with involved cervical lymph nodes and presumed head and neck squamous cell carcinoma. Metastatic squamous cell carcinoma to mediastinal lymph nodes usually is due to lung carcinoma; however, an association with an nnknovvn primary tumor is quite rare and only has been reported in the Japanese medical literature. 2 The patient reported here is the first with this situation described in the English-language medical literature that th e authors are aware of. CASE REPORT
A .56-year-old Hispanic man presented with three episodes of he moptysis. The patient described a p ersistent cough of 1 year's duration that was presumed to be seconchuy to bronchitis and a 30-lb weight loss in the last 8 months; he had a 50 pack-year smoking hist01y. The patie nt denied any exposure to tube rculosis; risk h1ctors for AIDS ; or symptoms of dyspnea, feve r, or night sweats. Past medical hist01y was non contrihut01y , and th e physical examination disclosed no abnormalities. The pati ent received a thorough but nondiagnostic evaluation For pulmomuy disease such as bronchiectasis, pne umonia, tuberculosis, aspergi ll osis, and other fungal infections, as well as pulmomuy hypertension. The c hest x- ray film was normal. Bronchoscopy showed e1ythema of th e mainstem bronchi , hut no cndoluminal mass was present. Blind biopsies of th e carina were normal as were brushings of all bronchopulmomuy segments. Bronchoscopic wash ings were not performed. Sputum cultures grew Candida albicans , which was considered a contamin ant. The patient was found to have positive hepatitis A antibodies without any evidence of current or recent infection. A CT scan of th e thorax identifi ed an 8-cm poste rior mediastin al mass in the subcarinal region (Fig 1). A barium swall ow exa mination showed compression of the esophagus, and e ndoscopy identifi ed an extrin sic mass with sli ghtly increased vascularity of th e esophageal mu cosa. The presumptive diagnosis was a benign mediastinal tumor, possibly of neurogenic origin. At ri ght thoracotomy, a lobulated, flnn mass was removed intact from th e suhcarin al area after di ssection and release from attachments to th e esophagus , to th e mainstem bronchi , and to th e pericardium. There was no true invasion of these structures. Exploration of th e ches t and the lung showed no fin·th er abnormalities. The patient tol erated the operation without co mplications and was disch arged home on th e 3rd postope rati ve day. The pathologic diagnosis was *From th e D epartment of Snrgmy, University of Nevada School of Medicin e, Las Vegas, NV. Mannscript received Janumy 23, 1998; revision accepted March 26, 1998. Correspondence to: Alex G. Little, MD, FCCP, Depart111ent of Surgenf, 2040 W Charleston Blv d, Suite 601 , Las Vegas, NV 89102; email: [email protected]
FIGUHE l. This CT scan shows a posterior mediastinal mass which abuts both mainstem bronchi , the aorta, and the spine.
of' matted yl mph nodes containing poorly diffe rentiated, ml'tastatic squamous cell carcinoma (F ig 2). A metastati c su1-vPy has not yieldeJ any evi dence of furt he r disease. The patient is currently being treated with a protocol for lu ng cancer with external beam radiation to th e thorax and chemotherapy with cisplatin and etoposide. Patie nt follow-up to elate has not revealed a pri1muy tumor, despite repeating th e bron choscopic examination during which both brushings and washin gs of eac h bronchopulmonmy segment were pe rformed. Again, no diagnosti c res ults were obtained. DISCUSSION
Unknown primary cancer metastatic to a single lymph node site is awell-known but relatively uncommon occurrence and most often is clue to adenocarcinoma. Sqnamous cell carcinoma at a metastatic site is fonnd in only approximately .5% of all patients with unknown primmy tumors. J.:l An even smaller percentage of patients present with involvement of mediastinal lymph nodes with squa-
FrG UHE 2. This photomicrograph is represe ntative of th e histologi c characteri stics of the mass shown in Figme l. Features of squamous cell carcinoma are present (he matoxylin-eosin, original X400).
CHEST I 114 I 3 I SEPTEMBER, 1998
939
mous cell metastasis. The Eastern Cooperative Oncology Group found that 20% of 220 patients with poorly differentiated metastatic carcinoma of unknown origin had their dominant metastatic site in the mediastinum; however, the majmity had multiple metastatic sites_1.4 In addition, adenocarcinoma, usually from the breast or the prostate, can undergo squamous conversion. vVhen adenocarcinoma is suspected, tissue should be submitted for immunoperoxidase staining or electron microscopy. 5 Squamous cell carcinoma metastatic to mediastinal and cervical lymph nodes can have a primary site in the lung; in the upper portion of the esophagus; in the skin; in the thymus; in the anus; and in the head and neck region including the larynx and pharynx. When upper and middle cervical lymph node involvement is present, the primary site usually is in the head and neck region. When the lower cervical and supraclavicular nodes are involved, lung cancer becomes a more plausible suspected primary site. However, even in these cases, of the 20 to 40% of patients in whom the primary tumor is identified, the majority of the primary tumors are in the head and neck region. 6 -8 When metastases are found in mediastinal lymph nodes, this likely represents occult lung cancer which should be searched for with fiberoptic bronchoscopy and a CT scan of the chest. 9 .1° Even without identification of a primary tumor, it seems reasonable that treatment should be directed towards non-small cell lung cancer with both radiation to the mediastinum and an appropriate chemotherapy regimen. Our patient is the first we are aware of reported in the English language medical literature, although instances have been described in the Japanese literature. 2 His symptoms of a persistent cough and several episodes of hemoptysis may lead the clinician to suspect occult lung cancer. However, a CT scan of the chest and operative exploration of the right thorax were normal except for the solitary posterior mediastinal mass . Fiberoptic bronchus-
940
copy with brushings and biopsy and an esophageal endoscopy showed no abnormalities as well. There is no evidence to this date of a primary tumor site. His primary tumor focus remains a mystery and is a rare example of unknown primaty squamous carcinoma.
REFERENCES
2
3
4
5 6
7 8
9
10
DeVita WT, Hellman S, Rosenberg SA. Cancer: principles and practice of oncology. Philadelphia, PA: LippincottRaven , 1997; 2428-2443 Yodonawa S, Mitsui K, Akaogi E, e t a!. Squamous cell carcinoma of unknown origin affecting mediastinal lymph nodes. Nippon Kyobu Shikkan Gakkai Zasshi 1996; 34:1364 Holleb AI, Fink DJ, Murphy GP. American cancer society textbook of clinical oncology. Atlanta, GA: American Cancer Society, 1991; 25-70, 194-212 Greco FA, Vaughn WK, Hainsworth JD. Advanced poorly differentiated carcinoma of unknown primary site: recognition of a treatable syndrome. Ann Intern Med 1986; 104:547553 Hainsworth J, Greco F. Poorly differentiated carcinoma of unknown primaty site. Orlando, FL: Grune & Stratton, 1986; 189-210 Lefe bvre J, Coche-Dequeant B, Van JT. CeiVical lymph nodes from an unknown primary tumor in 190 patients. Am J Surg 1990; 160:443-446 Spiro R, DeRose G, Strong E. Cervical node metastasis of occult origin. Am J Surg 1983; 146:441-446 Arita T, Kuramitsu T, Matsumoto T, e t al. Bronchogenic carcinoma: incidence of metastases to normal sized lymph nodes. Thorax 1995; 50:1267-1269 Bechtel J, Kelley W, Petty T, et al. Outcome of 51 patients with roentgenographically occult lung cancer detected by sputum cytologic testing: a community hospital program. Arch Intern Med 1994; 154:975-980 Potepan P, Meroni E, Spagnoli I, et a!. Non-small cell lung cancer: detection of mediastinal lymph node metastases by endoscopic ultrasound and CT. Eur Radio! 1996; 6:19-24
Selected Reports
/
•
/
:.'.
...-: .
.....
I
J
I
FIGUHE 3. Microscopic appearance of' the lamina] surf~tce of the aberrant artery. The arte1y was composed of' elastic lam inae (hcmatm.y li neosin , original X 100).
findings of pulmonary artery occlusion or atherosclerosis . Since th e pulmonary ligam e nt artery is originally th e muscular type, and th e re is no evide nce to suggest that a muscular-type artery can transform into an elastic type, one cannot accept that th e pulmonary li gament arteries led to th e "creation " of ILS as desc ribed by Stocker and Malczac. ~ Th e re has b een som e confusion between chronic bronchiectasis with e nlarged bronchial arte ri es du e to infhmmation and ILS with abe rrant arteries. In this case, ILS with cystic appearance cou ld be easily confused with chronic bronchiectasis. Howeve r, as ILS is a congenital lesion but most cases of chron ic bronch iectasis without symptoms in chi ldh ood are acqui red , it must be conclud ed that the aberrant artery of ILS is th e e la stic type , and th e e nlarged bronchial artery of chronic bronchiectasis is of th e musc ular type . Ishida et aP have reported th at ILS in chi ldre n was classified into two groups, th e central type and th e p eripheral type, according to th e reco nstruction of th e bronchial tree in th e seq uestrated lu ng. Th ey claim ed that th e p eriph e ral type is th e tru e ILS , and th e central typ e is a mixture and a sequela of anoth e r disease such as bronchial atresia. Th e form e r type in segment 10 areas and aberrant arte ri es was elastic in histologi c nature . Th e la tter type in variable sites of th e les ion and arteries was muscular. It is suggested th at characteristics of an aberrant artery would b e use ful for th e definiti ve diagnosis of ILS to avoid confusion with other acquired diseases rega rdless of the anatomic appea rance or the pati e nt's age. Preoperative diagnosis of ILS is difficult. Savic et al 1 indicated that ILS was suspected or diagnosed preoperati vely in only 47 of 100 cases , whi le extralobar sequestration was preoperatively diagnosed in on ly 6 of 66 cases. Diffe rential diagnostic possibiliti es include bronchiectasis, lung abscess, e mpyema, lung neoplasm , congenital cystic adcnomatoid malformation , s taphylococcal pn eumoni a with pneumatocele formation , and congenital diaphragmatic hernia (Bochdalek's he rnia). Traditionally, the diagnosis of' ILS has been performed b y angiography to conflrm the aberrant arterial and venous drainage. In the reported case, aortography was not definitive . Diagnostic 938
flndin gs could not be obtained because all aberrant arteries were fin e pulmonmy ligam ent arteries. MRI, 5 CT scans v.rith contrast enhanceme nt as in this case, and spiral CT scans are useful in selected cases. In the CT v.rith con trast enhancement, small linear enhancements V\rith a tumor shadow in the left posterior basal segment near the descending aorta were obtain ed. Therefore, ILS was suspected. Surgical treatment is recommended for ILS , not only in symptomatic cases but also in asymptomatic C
2 :3
4 5 6
Savic B, Birtel F'J , Thol en \IV, et al. Lung sequestration: report of' seven cases and review of' .540 published cases. Thorax 1979; 34:96-101 Blesovsky A. Pulmonmy sequestration: a report of an unusual casP and a review of the literatmc. Thorax 1967; 22:351-357 II , Hayas hi A. Tntralobar sequestration in TIshida H, Iajikano children- a new concept from the form of bronchial tree in sequestrated lung. ippon Kyobu Geka Gakkai Zasshi 1992; 40:957-968 o f pulmomuy ligament s Stocker JT, Malezac liT. A tudy arteries: relationsh ip to intralobar pu lmona1y sequestration. Chest 1984; 86:61 1-615 monstration of blood supply to pulmonary Doyle A J. De sequestration by MR angiography. AJH Am J Hoentgenol j 992; 158:989-990 Haller JA, Golladay ES , Pickard LH, et a!. Surgical management of' lung bud anomalies: ol bar emphysema, bronchogenic cyst, cystic adenomatoid m
Metastatic Squamous Cell Carcinoma of the Mediastinum With Unknown Primary Tumor* Neri Blanco, MD; Daniel M. Kirgan , MD; and Alex G. Little, MD, FCCP
Although metastatic carcinoma from an unknown pdmary tumor is known to occur, the combination of squamous cell carcinoma histologic findings and a mediastinal location is quite unusual. The evaluation Selected Reports
of a case of a patient with a posterior mediastinal mass, eventually shown to be metastatic squamous cell carcinoma of the mediastinum with unknown primary tumor, is described herein. Resection of the lymph node mass was performed and was followed by chemoradiation for presumed lung cancer. (CHEST 1998; 114:938-940) Key words: mecliastinal mass; metastasis; squamous cell carcinoma; unknown prima1y tumor
M
etastatic squamous cell carcinoma with an unknown primary tumor is a rare occurrence reported only in a handful of case reports. 1•2 These reports usually describe patients with involved cervical lymph nodes and presumed head and neck squamous cell carcinoma. Metastatic squamous cell carcinoma to mediastinal lymph nodes usually is due to lung carcinoma; however, an association with an nnknovvn primary tumor is quite rare and only has been reported in the Japanese medical literature. 2 The patient reported here is the first with this situation described in the English-language medical literature that th e authors are aware of. CASE REPORT
A .56-year-old Hispanic man presented with three episodes of he moptysis. The patient described a p ersistent cough of 1 year's duration that was presumed to be seconchuy to bronchitis and a 30-lb weight loss in the last 8 months; he had a 50 pack-year smoking hist01y. The patie nt denied any exposure to tube rculosis; risk h1ctors for AIDS ; or symptoms of dyspnea, feve r, or night sweats. Past medical hist01y was non contrihut01y , and th e physical examination disclosed no abnormalities. The pati ent received a thorough but nondiagnostic evaluation For pulmomuy disease such as bronchiectasis, pne umonia, tuberculosis, aspergi ll osis, and other fungal infections, as well as pulmomuy hypertension. The c hest x- ray film was normal. Bronchoscopy showed e1ythema of th e mainstem bronchi , hut no cndoluminal mass was present. Blind biopsies of th e carina were normal as were brushings of all bronchopulmomuy segments. Bronchoscopic wash ings were not performed. Sputum cultures grew Candida albicans , which was considered a contamin ant. The patient was found to have positive hepatitis A antibodies without any evidence of current or recent infection. A CT scan of th e thorax identifi ed an 8-cm poste rior mediastin al mass in the subcarinal region (Fig 1). A barium swall ow exa mination showed compression of the esophagus, and e ndoscopy identifi ed an extrin sic mass with sli ghtly increased vascularity of th e esophageal mu cosa. The presumptive diagnosis was a benign mediastinal tumor, possibly of neurogenic origin. At ri ght thoracotomy, a lobulated, flnn mass was removed intact from th e suhcarin al area after di ssection and release from attachments to th e esophagus , to th e mainstem bronchi , and to th e pericardium. There was no true invasion of these structures. Exploration of th e ches t and the lung showed no fin·th er abnormalities. The patient tol erated the operation without co mplications and was disch arged home on th e 3rd postope rati ve day. The pathologic diagnosis was *From th e D epartment of Snrgmy, University of Nevada School of Medicin e, Las Vegas, NV. Mannscript received Janumy 23, 1998; revision accepted March 26, 1998. Correspondence to: Alex G. Little, MD, FCCP, Depart111ent of Surgenf, 2040 W Charleston Blv d, Suite 601 , Las Vegas, NV 89102; email: [email protected]
FIGUHE l. This CT scan shows a posterior mediastinal mass which abuts both mainstem bronchi , the aorta, and the spine.
of' matted yl mph nodes containing poorly diffe rentiated, ml'tastatic squamous cell carcinoma (F ig 2). A metastati c su1-vPy has not yieldeJ any evi dence of furt he r disease. The patient is currently being treated with a protocol for lu ng cancer with external beam radiation to th e thorax and chemotherapy with cisplatin and etoposide. Patie nt follow-up to elate has not revealed a pri1muy tumor, despite repeating th e bron choscopic examination during which both brushings and washin gs of eac h bronchopulmonmy segment were pe rformed. Again, no diagnosti c res ults were obtained. DISCUSSION
Unknown primary cancer metastatic to a single lymph node site is awell-known but relatively uncommon occurrence and most often is clue to adenocarcinoma. Sqnamous cell carcinoma at a metastatic site is fonnd in only approximately .5% of all patients with unknown primmy tumors. J.:l An even smaller percentage of patients present with involvement of mediastinal lymph nodes with squa-
FrG UHE 2. This photomicrograph is represe ntative of th e histologi c characteri stics of the mass shown in Figme l. Features of squamous cell carcinoma are present (he matoxylin-eosin, original X400).
CHEST I 114 I 3 I SEPTEMBER, 1998
939
mous cell metastasis. The Eastern Cooperative Oncology Group found that 20% of 220 patients with poorly differentiated metastatic carcinoma of unknown origin had their dominant metastatic site in the mediastinum; however, the majmity had multiple metastatic sites_1.4 In addition, adenocarcinoma, usually from the breast or the prostate, can undergo squamous conversion. vVhen adenocarcinoma is suspected, tissue should be submitted for immunoperoxidase staining or electron microscopy. 5 Squamous cell carcinoma metastatic to mediastinal and cervical lymph nodes can have a primary site in the lung; in the upper portion of the esophagus; in the skin; in the thymus; in the anus; and in the head and neck region including the larynx and pharynx. When upper and middle cervical lymph node involvement is present, the primary site usually is in the head and neck region. When the lower cervical and supraclavicular nodes are involved, lung cancer becomes a more plausible suspected primary site. However, even in these cases, of the 20 to 40% of patients in whom the primary tumor is identified, the majority of the primary tumors are in the head and neck region. 6 -8 When metastases are found in mediastinal lymph nodes, this likely represents occult lung cancer which should be searched for with fiberoptic bronchoscopy and a CT scan of the chest. 9 .1° Even without identification of a primary tumor, it seems reasonable that treatment should be directed towards non-small cell lung cancer with both radiation to the mediastinum and an appropriate chemotherapy regimen. Our patient is the first we are aware of reported in the English language medical literature, although instances have been described in the Japanese literature. 2 His symptoms of a persistent cough and several episodes of hemoptysis may lead the clinician to suspect occult lung cancer. However, a CT scan of the chest and operative exploration of the right thorax were normal except for the solitary posterior mediastinal mass . Fiberoptic bronchus-
940
copy with brushings and biopsy and an esophageal endoscopy showed no abnormalities as well. There is no evidence to this date of a primary tumor site. His primary tumor focus remains a mystery and is a rare example of unknown primaty squamous carcinoma.
REFERENCES
2
3
4
5 6
7 8
9
10
DeVita WT, Hellman S, Rosenberg SA. Cancer: principles and practice of oncology. Philadelphia, PA: LippincottRaven , 1997; 2428-2443 Yodonawa S, Mitsui K, Akaogi E, e t a!. Squamous cell carcinoma of unknown origin affecting mediastinal lymph nodes. Nippon Kyobu Shikkan Gakkai Zasshi 1996; 34:1364 Holleb AI, Fink DJ, Murphy GP. American cancer society textbook of clinical oncology. Atlanta, GA: American Cancer Society, 1991; 25-70, 194-212 Greco FA, Vaughn WK, Hainsworth JD. Advanced poorly differentiated carcinoma of unknown primary site: recognition of a treatable syndrome. Ann Intern Med 1986; 104:547553 Hainsworth J, Greco F. Poorly differentiated carcinoma of unknown primaty site. Orlando, FL: Grune & Stratton, 1986; 189-210 Lefe bvre J, Coche-Dequeant B, Van JT. CeiVical lymph nodes from an unknown primary tumor in 190 patients. Am J Surg 1990; 160:443-446 Spiro R, DeRose G, Strong E. Cervical node metastasis of occult origin. Am J Surg 1983; 146:441-446 Arita T, Kuramitsu T, Matsumoto T, e t al. Bronchogenic carcinoma: incidence of metastases to normal sized lymph nodes. Thorax 1995; 50:1267-1269 Bechtel J, Kelley W, Petty T, et al. Outcome of 51 patients with roentgenographically occult lung cancer detected by sputum cytologic testing: a community hospital program. Arch Intern Med 1994; 154:975-980 Potepan P, Meroni E, Spagnoli I, et a!. Non-small cell lung cancer: detection of mediastinal lymph node metastases by endoscopic ultrasound and CT. Eur Radio! 1996; 6:19-24
Selected Reports