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Sarcoma of the small intestine
~36
JOURNAL
OF
THE
SARCOMA
FACULTY
OF T H E
SMALL
OF
RADIOLOGISTS
INI'ESTINE
BY ROY A S T L E Y THE CHILDREN'S HOSPITAL, BIRMINGHAM
PRIMARY s a r c o m a is c o m p a r a t i v e l y rare i n t h e a l i m e n t a r y tract. I t o c c u r s m o s t o f t e n (6o p e r c e n t ) in t h e small intestine, w h e r e it is t h r e e t i m e s as c o m m o n as c a r c i n o m a . T h e d i s t r i b u t i o n is as follows ( F e l d m a n , i 9 4 5 ) : I l e u m , 55 p e r c e n t ; j e j u n u m , 3 ° p e r c e n t ; d u o d e n u m , 15 p e r cent. O f t h e ileum, t h e t e r m i n a l p o r t i o n is a f a v o u r e d site. T h e t u r n o u t is a l y m p h o s a r c o m a in 5 ° p e r c e n t of t h e cases. L i u ( i 9 2 5 ) f o u n d a n a n n u l a r g r o w t h in a b o u t t w o - t h i r d s a n d a localized p o l y p o i d g r o w t h in o n e - t h i r d , e i t h e r i n t r a - or e x t r a l u m e n a l a n d s o m e t i m e s m u l t i p l e . All ages are affected, males p r e d o m i n a t i n g b y a b o u t t w o to one. I t is m o s t c o m m o n b e t w e e n 20 a n d 5 ° years, b u t Io p e r c e n t o c c u r in c h i l d r e n a n d infants. Clinically, t h e p r e s e n t i n g s y m p t o m s are o f t e n t h o s e of partial o b s t r u c t i o n . Complete o b s t r u c t i o n is u n c o m m o n a n d i n these i n s t a n c e s it is f r e q u e n t l y d u e to i n t u s s u s c e p t i o n . P e r f o r a t i o n c a n o c c u r b u t it is rare. I n over half t h e cases t h e r e is a p a l p a b l e t u m o u r b u t t h e exact diagnosis is rarely m a d e clinically. A c c o r d i n g to F e l d m a n ( i 9 4 5 ) t h e radiological signs are t h o s e of s o m e d e g r e e o f stenosis. B e l o w a dilated loop of small i n t e s t i n e lies t h e n e o p l a s t i c s e g m e n t , w h i c h s h o w s c e d e m a t o u s m u c o s a , loss of p a t t e r n , rigidity, or a typical n e o p l a s t i c filling defect. M u l t i p l e d i l a t e d a n d s t e n o s e d areas m a y p r o d u c e s a u s a g e - s h a p e d s e g m e n t s ; loops of i n t e s t i n e m a y b e m a t t e d t o g e t h e r . I n t h e localized p o l y p o i d t y p e t h e filling defect is r o u n d e d a n d m o r e s h a r p l y d e m a r c a t e d . E x t r a l u m e n a l s a r c o m a s p r o d u c e s m o o t h p r e s s u r e defects in a d j a c e n t loops of s m a l l intestine, w i t h s o m e degree of o b s t r u c t i o n . W e b e r a n d K i r k l i n ( I 9 4 7 ) m a i n t a i n t h a t t h e radiologist s h o u l d b e satisfied w i t h a diagnosis of ' t u m o u r ' ; he is p r o b a b l y u n w i s e in m o s t i n s t a n c e s to a t t e m p t to differentiate t h e m a l i g n a n t lesions f r o m t h e b e n i g n . T h e cases briefly d e s c r i b e d b e l o w o c c u r r e d in c h i l d r e n ; t h e y s h o w two v e r y d i f f e r e n t ways in w h i c h l y m p h o s a r c o m a of t h e i l e u m m a y p r e s e n t itself. Case i .--
HISTORY.--Male, aged 6. He was perfectly well until five weeks before admission to hospital. He lost his appetite and gradually became listless, tired, and pale. There was loss of weight and his parents had noticed recent abdominal enlargement. T h e r e was no nausea or vomiting ; at first he was slightly constipated but bowel action returned to normal. There were no urinary symptoms. ON EXAMINATrON.--There was a large, slightly tender, and slightly mobile mass in the central abdomen. It was hard, with: well-defined smooth edges, and felt superficial, as if it extended right to the anterior abdominal walt. T h e most notable feature was that it was resonant to percussion. The liver and spleen were not palpable but there appeared to be another smaller mass deep in the right lower quadrant. Physical examination of the other systems was normal except for pallor. Examination of the f~eces was repeatedly strongly positive for occult blood. A blood-count showed H b 5 ° per c e n t ; R.B.C. 3'5 million and W.B.C. i8,ooo per c . m m . (85 per cent polymorphonuelears). X-rays.--There was a large ill-defined mass in the abdomen, displacing the gas shadows of the stomach upwards and the colon outwards, around its periphery. Within the mass was a large air-containing cavity, extending upwards to the level of the lower border of T. 12 and downwards to L.5, with a projection downwards over the right sacro-iliac joint. T h e walls of the cavity were clear-cut but somewhat irregular, almost umbilicated in places. There were also a few small air shadows within the area of the mass that were distinguishable as loops of small intestine. An erect film showed a considerable fluid level in the cavity (Fig. I I6). A supine lateral view showed that the cavity extended forwards close to the anterior abdominal wall. Barium Meal.--The stomach was shown to be displaced upwards. At one hour the barium was partly in the small intestine, some above and some below the mass. At 4 hours most of the barium was in the ascending and transverse colon; some had entered the cavity and mingled with the fluid contents but most had bypassed it. At its lower pole a loop of ileum was seen to have a ' side-to-side ' connexion with the cavity.
SARCOMA
OF
THE
Fig. i16.--Cass I.
E r e c t film, s h o w i n g central a b d o m i n a l o p a c i t y containing a large cavity w i t h a fluid level.
Fig. iiS.--Case i . E r e c t film, four h o u r s p.c. Nlost of t h e b a r i u m has b y - p a s s e d t h e cavity b u t a little has m i n g l e d w i t h its fluid contents. A c o m m u n i c a t i o n b e t w e e n the cavity a n d the i l e u m is s h o w n o v e r l y i n g the r i g h t saero-iliae joint.
SMALL
INTESTINE
Fig. Ii7.--Cage I.
Erect film, one h o u r after b a r i u m ; s t o m a c h displaced u p w a r d s .
F~g. II9.--Case I. E r e c t fateral film, f o u r hours p.e,
Cornm u n i c a t i o n b e t w e e n ea~ity a n d i l e u m is d e m o n s t r a t e d .
i37
138
JOURNAL
OF
THE
FACULTY
OF
RADIOLOGISTS
By 22 hours only a little b a r i u m remained in it. I n the series of films the irregular nature of the cavity was well d e m o n s t r a t e d ; a t u b u l a r backward prolongation was notable. (Figs. i i 7 - i 2 o . ) LAPAROTOMY (after t r a n s f u s i o n ) . - - T h i s revealed a little free fluid in the peritoneum. T h e r e was a large neoplastic mass with adherent gut and o m e n t u m . T h e p e r i t o n e u m was involved and the condition was quite inoperable. A biopsy showed a highly anaplastic n e o p l a s m - - s o anaplastic that its origin could not be decided. Six weeks after admission, i.e., I I weeks from the onset of symptoms, the child died in a state of cachexia. AuToPS'Z.--There was a very large mass filling the abdomen, including the true pelvis. It was firm in some parts, soft and encephaloid in others. Coils of intestine were either attached to the mass or seemed to
Fig. IaO. Case i. Erect lateral film 2z hours p.c. Very little barium remains in the cavity. Its irregular nature, the smaller cavities, and the tubular prolongation backwards are seen.
Fig. i 2 I . - - F e m a l e , age I5 months. Supine film shows a diffuse abdominal opacity containing loops of small intestine and a large irregularly-shaped cavity. Autopsy: T.B. peritonitis with loculated perforation. T h e cavity, enclosed by adherent coils of gut, contained f~ecal fluid.
disappear into it. O n dissection, a targe cavity with ragged greyish-white and black walls was found within the mass. Several smaller cavities were present, communicating with the main cavity ; some were lined with intestinal mucosa. Dissection u p w a r d s from the rectum showed that the large intestine was not involved, but only 2 cm. of the terminal ileum was intact. Its proximal end was entirely embedded in the growth. Dissection downwards from the d u o d e n u m showed that the j e j u n u m and u p p e r ileum were firmly embedded in the mass but had a normal mucosa. At the junction of the middle and lower thirds of the ileum all layers of the intestinal wall were suddenly replaced by a u n i f o r m structureless white tissue for an area about I'5 cm. long. Distal to this, the intestine was completely enclosed in and fused with the t u m o u r mass. Separate small t u m o u r masses were present in the mesentery, retroperitoneatly, and on the inferior surface of the diaphragm. T h e r e were small areas in the pancreas and left kidney but none in the liver or thorax. Frozen sections of the g r o w t h showed the structure of a lymphosarcoma. C o m m e n t . - - I t is interesting to note h o w m u c h of the intestine was involved, yet with a history of normal bowel action. I n the differential diagnosis, Fig. i21 is of interest. T h i s shows a cavity, the result of a localized perforation, enclosed by adherent coils of gut, in a case of tuberculous peritonitis.
SARCOMA
OF
THE
SMALL
INTESTINE
139
Case 2 . - HiSTOrtY.--Male, aged i:~. He was quite well until three weeks before admission, w h e n h e developed leftsided abdominal pain. T h i s came on suddenly and lasted from a few m i n u t e s up to half a n hour. It was severe and made h i m sick and faint, although actual vomiting was infrequent. A t first, the attacks occurred three or four times a day b u t their frequency increased u p to three in one hour. His appetite remained good and bowel action was normal. ExAMINATION.--Temperature 99.6 ° F. A b d o m e n rather rigid with guarding in the left u p p e r quadrant. W.B.C. 12,ooo per c.mm. (78 per cent polymorphonuclears). A n enema was r e t u r n e d unchanged. He had one attack of severe pain followed by vomiting. X - r a y . - - A n erect film of the a b d o m e n showed the typical picture of low small intestinal obstruction, with distended coils of j e j u n u m a n d ileum, containing fluid levels. LAPAltOTOMY.--Revealed an ileo-ileat intussusception, 4 ft. above the ileocsecal valve. A t t h e time of the operation it had travelled half way along the ascending colon. T h e r e was n o obvious cause and the intussusception was reduced. Progress was very satisfactory until 8 days later, w h e n pain and v o m i t i n g returned. T h i s time a mass was palpable in the right iliac fossa. T h e a b d o m e n was reopened. T h e intussusception had recurred and this time reduction was n o t possible. Consequently io in. of ileum were rcsected, with e n d - t o - e n d anastomosis. SPEClMEN.--Projecting into the l u m e n at the apex of the intussusception (but not palpable from the outside of the cedematous bowel) was a firm m u c o u s - m e m b r a n e - c o v e r e d mass, a b o u t 3 × 2'5 × 2 era. in size. Its cut surface was smooth, greyish-white, with reddish spots. Histological examination showed t h e structure of a lymphosarcoma, densely infiltrating all coats b u t fairly well demarcated at the periphery. T h e mesenteric lymph-glands were pea-sized and showed an inflammatory reaction b u t n o neoplastic infiltration. C o m m e n t . - - T h i s i s an example of the localized intralumenal polypoid type of lymphosarcoma, in contrast to the first case with its m a t t e d coils of intestine. T h e recurrence of the intussusception necessitated resection of the involved segment and the unwitting removal of the growth. Yet, although t h e adjacent glands were apparently not involved, the patient has since died of very generalized s p r e a d - - u n d e r four m o n t h s after the appearance of the first symptom.
SUMMARY T h e f e a t u r e s o f s a r c o m a o f t h e s m a l l i n t e s t i n e are b r i e f l y d i s c u s s e d . Two cases of lymphos a r c o m a o f t h e i l e u m are d e s c r i b e d . In one a large tumour mass involving most of the small i n t e s t i n e p r o d u c e d little i n t e r f e r e n c e w i t h b o w e l a c t i o n . In the second a small localized growth caused recurrent intussusception. BIBLIOGRAPHY BERMAN, H. (1945), Araer. J. Surg., 7 o, 121. DOUB, H. P., and JONES, H. C. (I936), Radiology, 26, 209. FELDMAN, M. (I945), Clinical Roentgenology of the Digestive Tract. Baltimore : T h e Williams & Wilkins Co. LI1:, J. H. (I925), Arch. Surg., zI, 6o2. WEBER, H. M., and KIRKLIN, B. R. (I947) , Amer. y. Roentgenol., 47, 243.
JOURNAL
OF
THE
SARCOMA
FACULTY
OF T H E
SMALL
OF
RADIOLOGISTS
INI'ESTINE
BY ROY A S T L E Y THE CHILDREN'S HOSPITAL, BIRMINGHAM
PRIMARY s a r c o m a is c o m p a r a t i v e l y rare i n t h e a l i m e n t a r y tract. I t o c c u r s m o s t o f t e n (6o p e r c e n t ) in t h e small intestine, w h e r e it is t h r e e t i m e s as c o m m o n as c a r c i n o m a . T h e d i s t r i b u t i o n is as follows ( F e l d m a n , i 9 4 5 ) : I l e u m , 55 p e r c e n t ; j e j u n u m , 3 ° p e r c e n t ; d u o d e n u m , 15 p e r cent. O f t h e ileum, t h e t e r m i n a l p o r t i o n is a f a v o u r e d site. T h e t u r n o u t is a l y m p h o s a r c o m a in 5 ° p e r c e n t of t h e cases. L i u ( i 9 2 5 ) f o u n d a n a n n u l a r g r o w t h in a b o u t t w o - t h i r d s a n d a localized p o l y p o i d g r o w t h in o n e - t h i r d , e i t h e r i n t r a - or e x t r a l u m e n a l a n d s o m e t i m e s m u l t i p l e . All ages are affected, males p r e d o m i n a t i n g b y a b o u t t w o to one. I t is m o s t c o m m o n b e t w e e n 20 a n d 5 ° years, b u t Io p e r c e n t o c c u r in c h i l d r e n a n d infants. Clinically, t h e p r e s e n t i n g s y m p t o m s are o f t e n t h o s e of partial o b s t r u c t i o n . Complete o b s t r u c t i o n is u n c o m m o n a n d i n these i n s t a n c e s it is f r e q u e n t l y d u e to i n t u s s u s c e p t i o n . P e r f o r a t i o n c a n o c c u r b u t it is rare. I n over half t h e cases t h e r e is a p a l p a b l e t u m o u r b u t t h e exact diagnosis is rarely m a d e clinically. A c c o r d i n g to F e l d m a n ( i 9 4 5 ) t h e radiological signs are t h o s e of s o m e d e g r e e o f stenosis. B e l o w a dilated loop of small i n t e s t i n e lies t h e n e o p l a s t i c s e g m e n t , w h i c h s h o w s c e d e m a t o u s m u c o s a , loss of p a t t e r n , rigidity, or a typical n e o p l a s t i c filling defect. M u l t i p l e d i l a t e d a n d s t e n o s e d areas m a y p r o d u c e s a u s a g e - s h a p e d s e g m e n t s ; loops of i n t e s t i n e m a y b e m a t t e d t o g e t h e r . I n t h e localized p o l y p o i d t y p e t h e filling defect is r o u n d e d a n d m o r e s h a r p l y d e m a r c a t e d . E x t r a l u m e n a l s a r c o m a s p r o d u c e s m o o t h p r e s s u r e defects in a d j a c e n t loops of s m a l l intestine, w i t h s o m e degree of o b s t r u c t i o n . W e b e r a n d K i r k l i n ( I 9 4 7 ) m a i n t a i n t h a t t h e radiologist s h o u l d b e satisfied w i t h a diagnosis of ' t u m o u r ' ; he is p r o b a b l y u n w i s e in m o s t i n s t a n c e s to a t t e m p t to differentiate t h e m a l i g n a n t lesions f r o m t h e b e n i g n . T h e cases briefly d e s c r i b e d b e l o w o c c u r r e d in c h i l d r e n ; t h e y s h o w two v e r y d i f f e r e n t ways in w h i c h l y m p h o s a r c o m a of t h e i l e u m m a y p r e s e n t itself. Case i .--
HISTORY.--Male, aged 6. He was perfectly well until five weeks before admission to hospital. He lost his appetite and gradually became listless, tired, and pale. There was loss of weight and his parents had noticed recent abdominal enlargement. T h e r e was no nausea or vomiting ; at first he was slightly constipated but bowel action returned to normal. There were no urinary symptoms. ON EXAMINATrON.--There was a large, slightly tender, and slightly mobile mass in the central abdomen. It was hard, with: well-defined smooth edges, and felt superficial, as if it extended right to the anterior abdominal walt. T h e most notable feature was that it was resonant to percussion. The liver and spleen were not palpable but there appeared to be another smaller mass deep in the right lower quadrant. Physical examination of the other systems was normal except for pallor. Examination of the f~eces was repeatedly strongly positive for occult blood. A blood-count showed H b 5 ° per c e n t ; R.B.C. 3'5 million and W.B.C. i8,ooo per c . m m . (85 per cent polymorphonuelears). X-rays.--There was a large ill-defined mass in the abdomen, displacing the gas shadows of the stomach upwards and the colon outwards, around its periphery. Within the mass was a large air-containing cavity, extending upwards to the level of the lower border of T. 12 and downwards to L.5, with a projection downwards over the right sacro-iliac joint. T h e walls of the cavity were clear-cut but somewhat irregular, almost umbilicated in places. There were also a few small air shadows within the area of the mass that were distinguishable as loops of small intestine. An erect film showed a considerable fluid level in the cavity (Fig. I I6). A supine lateral view showed that the cavity extended forwards close to the anterior abdominal wall. Barium Meal.--The stomach was shown to be displaced upwards. At one hour the barium was partly in the small intestine, some above and some below the mass. At 4 hours most of the barium was in the ascending and transverse colon; some had entered the cavity and mingled with the fluid contents but most had bypassed it. At its lower pole a loop of ileum was seen to have a ' side-to-side ' connexion with the cavity.
SARCOMA
OF
THE
Fig. i16.--Cass I.
E r e c t film, s h o w i n g central a b d o m i n a l o p a c i t y containing a large cavity w i t h a fluid level.
Fig. iiS.--Case i . E r e c t film, four h o u r s p.c. Nlost of t h e b a r i u m has b y - p a s s e d t h e cavity b u t a little has m i n g l e d w i t h its fluid contents. A c o m m u n i c a t i o n b e t w e e n the cavity a n d the i l e u m is s h o w n o v e r l y i n g the r i g h t saero-iliae joint.
SMALL
INTESTINE
Fig. Ii7.--Cage I.
Erect film, one h o u r after b a r i u m ; s t o m a c h displaced u p w a r d s .
F~g. II9.--Case I. E r e c t fateral film, f o u r hours p.e,
Cornm u n i c a t i o n b e t w e e n ea~ity a n d i l e u m is d e m o n s t r a t e d .
i37
138
JOURNAL
OF
THE
FACULTY
OF
RADIOLOGISTS
By 22 hours only a little b a r i u m remained in it. I n the series of films the irregular nature of the cavity was well d e m o n s t r a t e d ; a t u b u l a r backward prolongation was notable. (Figs. i i 7 - i 2 o . ) LAPAROTOMY (after t r a n s f u s i o n ) . - - T h i s revealed a little free fluid in the peritoneum. T h e r e was a large neoplastic mass with adherent gut and o m e n t u m . T h e p e r i t o n e u m was involved and the condition was quite inoperable. A biopsy showed a highly anaplastic n e o p l a s m - - s o anaplastic that its origin could not be decided. Six weeks after admission, i.e., I I weeks from the onset of symptoms, the child died in a state of cachexia. AuToPS'Z.--There was a very large mass filling the abdomen, including the true pelvis. It was firm in some parts, soft and encephaloid in others. Coils of intestine were either attached to the mass or seemed to
Fig. IaO. Case i. Erect lateral film 2z hours p.c. Very little barium remains in the cavity. Its irregular nature, the smaller cavities, and the tubular prolongation backwards are seen.
Fig. i 2 I . - - F e m a l e , age I5 months. Supine film shows a diffuse abdominal opacity containing loops of small intestine and a large irregularly-shaped cavity. Autopsy: T.B. peritonitis with loculated perforation. T h e cavity, enclosed by adherent coils of gut, contained f~ecal fluid.
disappear into it. O n dissection, a targe cavity with ragged greyish-white and black walls was found within the mass. Several smaller cavities were present, communicating with the main cavity ; some were lined with intestinal mucosa. Dissection u p w a r d s from the rectum showed that the large intestine was not involved, but only 2 cm. of the terminal ileum was intact. Its proximal end was entirely embedded in the growth. Dissection downwards from the d u o d e n u m showed that the j e j u n u m and u p p e r ileum were firmly embedded in the mass but had a normal mucosa. At the junction of the middle and lower thirds of the ileum all layers of the intestinal wall were suddenly replaced by a u n i f o r m structureless white tissue for an area about I'5 cm. long. Distal to this, the intestine was completely enclosed in and fused with the t u m o u r mass. Separate small t u m o u r masses were present in the mesentery, retroperitoneatly, and on the inferior surface of the diaphragm. T h e r e were small areas in the pancreas and left kidney but none in the liver or thorax. Frozen sections of the g r o w t h showed the structure of a lymphosarcoma. C o m m e n t . - - I t is interesting to note h o w m u c h of the intestine was involved, yet with a history of normal bowel action. I n the differential diagnosis, Fig. i21 is of interest. T h i s shows a cavity, the result of a localized perforation, enclosed by adherent coils of gut, in a case of tuberculous peritonitis.
SARCOMA
OF
THE
SMALL
INTESTINE
139
Case 2 . - HiSTOrtY.--Male, aged i:~. He was quite well until three weeks before admission, w h e n h e developed leftsided abdominal pain. T h i s came on suddenly and lasted from a few m i n u t e s up to half a n hour. It was severe and made h i m sick and faint, although actual vomiting was infrequent. A t first, the attacks occurred three or four times a day b u t their frequency increased u p to three in one hour. His appetite remained good and bowel action was normal. ExAMINATION.--Temperature 99.6 ° F. A b d o m e n rather rigid with guarding in the left u p p e r quadrant. W.B.C. 12,ooo per c.mm. (78 per cent polymorphonuclears). A n enema was r e t u r n e d unchanged. He had one attack of severe pain followed by vomiting. X - r a y . - - A n erect film of the a b d o m e n showed the typical picture of low small intestinal obstruction, with distended coils of j e j u n u m a n d ileum, containing fluid levels. LAPAltOTOMY.--Revealed an ileo-ileat intussusception, 4 ft. above the ileocsecal valve. A t t h e time of the operation it had travelled half way along the ascending colon. T h e r e was n o obvious cause and the intussusception was reduced. Progress was very satisfactory until 8 days later, w h e n pain and v o m i t i n g returned. T h i s time a mass was palpable in the right iliac fossa. T h e a b d o m e n was reopened. T h e intussusception had recurred and this time reduction was n o t possible. Consequently io in. of ileum were rcsected, with e n d - t o - e n d anastomosis. SPEClMEN.--Projecting into the l u m e n at the apex of the intussusception (but not palpable from the outside of the cedematous bowel) was a firm m u c o u s - m e m b r a n e - c o v e r e d mass, a b o u t 3 × 2'5 × 2 era. in size. Its cut surface was smooth, greyish-white, with reddish spots. Histological examination showed t h e structure of a lymphosarcoma, densely infiltrating all coats b u t fairly well demarcated at the periphery. T h e mesenteric lymph-glands were pea-sized and showed an inflammatory reaction b u t n o neoplastic infiltration. C o m m e n t . - - T h i s i s an example of the localized intralumenal polypoid type of lymphosarcoma, in contrast to the first case with its m a t t e d coils of intestine. T h e recurrence of the intussusception necessitated resection of the involved segment and the unwitting removal of the growth. Yet, although t h e adjacent glands were apparently not involved, the patient has since died of very generalized s p r e a d - - u n d e r four m o n t h s after the appearance of the first symptom.
SUMMARY T h e f e a t u r e s o f s a r c o m a o f t h e s m a l l i n t e s t i n e are b r i e f l y d i s c u s s e d . Two cases of lymphos a r c o m a o f t h e i l e u m are d e s c r i b e d . In one a large tumour mass involving most of the small i n t e s t i n e p r o d u c e d little i n t e r f e r e n c e w i t h b o w e l a c t i o n . In the second a small localized growth caused recurrent intussusception. BIBLIOGRAPHY BERMAN, H. (1945), Araer. J. Surg., 7 o, 121. DOUB, H. P., and JONES, H. C. (I936), Radiology, 26, 209. FELDMAN, M. (I945), Clinical Roentgenology of the Digestive Tract. Baltimore : T h e Williams & Wilkins Co. LI1:, J. H. (I925), Arch. Surg., zI, 6o2. WEBER, H. M., and KIRKLIN, B. R. (I947) , Amer. y. Roentgenol., 47, 243.