대 한 방 사 선 의 학 회 지 1992 ; 28 (5) : 794~ 797 Journal 01 Korean Radiological Society, September, 1992

Multiple Hamartomas (Mese야nc야hηlyr U nilateral Chest Wall in Infancy: CT Findings

Myung Joon Kim, M.D. , Choon Sik Yoon , M.D. , Ki Keun Oh, M.D. , Jong Tae Lee, M.D. , Woo Hee Jung, M.D. *

Department 01 Di‘agnostic Radiology, Severaηce Hospital, Yonsei [J，ηjνersity College 01 Medici‘ηe

- Abstract -

A case of multiple hamartomas of the unilateral chest wall in a four month old infant is presented. There

have been a few reports on the CT findings of the chest wall hamartoma in infancy. We describe bone changes

of the ribs and mineralization of this rare tumor on the CT scan , and the locations of two separate masses

Index Words: Infant , newborn , skeletal system

Ribs , neoplasms 474.319

Thorax , CT 47 1. 1211

Hamartoma

Chest wall hamartoma (mesenchymoma) is

very rare in infants. This mass usually presents

at birth and as a single , extrapleural mass aris­

ing from one or more ribs. A few cases of multi­

ple hamartomas have been reported (1-4). Y et , the cause and incidence of multiple lesions are

unknown.

We have performed whole body bone scan

with 99m Tc-MDP and CT scan , and describe

the CT findings of multiple hamartomas of the

chest wall and the locations of two separate

lesions.

CASE REPORT

A four month old male infant was admitted

to our hospital with productive cough for 1

month. A chest radiograph showed a large mass

(abou t 4 x 5 x 7 cm) of the left thorax , destroy­

ing 3rd and 4th ribs , and focal thinning of 2nd ,

* 연세대학교 의과대학 명리학교실

5th ribs (Fig . 1). Another small mass (about

2 x 3 x 3 cm) ansmg from the costovertebral

junction of the left 10th rib , separated from the

above lesion , was found after the whole bone scan

with 99m Tc-MDP (Fig. 2). Adjacent 9th and

11 th posterior ribs were eroded by this mass.

Faint , irregular mineralizations were noted

within these two masses.

On CT scan , the soft tissue masses contain­

ing conglomerate , spiculated calcific and ossific

densities were not surrounded by the cortical

bone. Underlying ribs showed the cortical ex­

pansion and destruction , and increased density

of medulla (Fig. 3a). Focal low density was

suspected within the large mass. The left

transverse process of the 10th thoracic vertebra

was involved by the small mass located in the

costovertebral junction (Fig. 3b)

Portions of the left 2nd-5th ribs and 9th , 10th

ribs with these masses were removed. The chest

* Department 01 Pathology, Yoηsei University College 01 Mediciηc

이 논문은 1992년 1월 27일 접수하여 1992년 6월 9일에 채 택 되 었 음.

Received January 27. Accepted June 9, 1992

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Myung Joon Kim , et al : Multiple Hamartomas of the Unilateral Chest Wall in Infancy

tervening stroma were revealed. Fibroblastic pro­

liferation with calcifications and ossifying

trabeculae were noted in the chondroid portion.

wall was repaired with Marlex mesh

Gross specimen showed a h emorrhagic por­

tion , clearly spearated from a cartilaginous por­

tion (Fig. 4). Histologically , a cavernous space

filled with blood and fibrous material in the in-

DISCUSSION

In most of the previous reports , the chest wall

hamartoma had been presented as a single mass

(1-8). In 1964, Hopkins and Freitas (4) reported

a case of bilateral osteochondromas of the ribs

in an infancy. But Dahlin (5) contended that

these bilateral masses most likely were benign

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Fig. 1. Chest radiograph shows a large mass in the left chest wall with partial destruction of the 3rd and 4th ribs. A small mass (arrows) ansmg from the costovertebral junction of the left 10th rib is poorly seen ‘ Adjacent 2nd , 5th and 9th , 11th ribs are erod­ed by these masses

~.

Fig.2. Posterior image of 99m Tc-MDP bone scan shows high activities within two masses

a b

Fig.3. a . Axial CT scan demonstrates a well demarcated mass occupying much of the left hemithorax . Con glomerate , spiculated calcifï c and ossific densiti es are seen within a large mass . Increased density of the in­tramedullary portion of the 3rd rib (arrow) is noted b. CT scan 6 cm lower than Fig . 3a shows a small mass of the left 10th rib , destroying the left transve rse process of 10th thoracic vertebra. It also contains clumpy calcific and ossific densities

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Journal of Korean Radiological Society 1992 ; 28 (5) : 794~ 797

Fig.4. Resected tumor , contiguous to the ribs , shows a solid portion and a blood fìlled cystic component (white arrows) . The 3rd rib shows the cortical destruction and the intramedullary calcifìcation (arrows).

chest wall hamartomas. Thereafter a few cases

of multiple hamartomas of the chest wall have

been reported in the English literature (1-4)

The plain radiographic findings were reviewed

by many authors (1-7). But the CT features of the chest wall hamartoma have not been well

documented (3 ,7 ,8). Histopathologically this le­

sion typically has cyst-like portion filled with

blood and solid , chondroid area with fibroblastic

proliferation , and significant amounts of

mineralization (1-3 ,5-7).

Initia\l y we missed a sma\l mass of the left

lower thorax on a chest radiograph. But whole

body bone scan with 99m Tc-MDP was helpful

in the reappraisal of chest radiograph due to in­tense uptakes of radiopharmaceutical by these

masses , even though the mass size varied great­

ly . This finding may suggest that extensive

mineraJiza tion and formation of ossifying

trabeculae are present without regard to the mass

size . Gwyther (3) noted that uptake is dependent

on the relative rate of growth and proportion of

cartilagenous and vascular componen t.

Schlesinger et al (7) reported the CT and MR

findings of a case of chest wall hamartoma and

correlated the MR features with gross pathology.

One of the CT findings they described in their

case was that the epicenter of the chest wall mass

was in the rib as cortical bone surrounded the

mass. On the contrary, CT scans of bone win­

dow setting did not demonstrate cortical bone

surrounding the periphery of mass in the patient

we presen t. We think that cortical change of the

ribs may depend on the degree of cortical expan­

sion and destruction by the intramedullary soft

tlssue mass.

Conglomerate , spiculated calcifications and

ossifications within th masses were more well

defined on the CT scan than those noted on the

plain radiograph. Increased density adjacent to

the intramedullary soft tissue mass was reveal­

ed as the mineralized portion of hamartoma.

Focallow density within a large mass correspon­

ed to the cyst-like blood filled space of the

speClmen.

Oakley et al (1) reported that it tended to in­

volve the main body of the rib and lie away from

the costochondral or costovertebral junction. In

our case , a large mass involved the main body

of the ribs , but a small one was located in the

costovertebral junction of the rib and involved

the left transverse process of 10th thoracic

vertebra . These findings may indicate that the

location of chest wall hamartoma is not unique

Two separate hamartomas of the unilateral

chest wall is extremely rare . Detection of another

small mass , similar to the radiologic pattern of

a large mass , may suggest a metastasis. A benign

hamartoma may be mistaken for a malignant le­

sion because of foUowing radiologic findings; cor­

tical destruction and involvement of multiple ribs

or adjacent bone as in the case we encountered

But the characteristic plain radiographic and CT

findings such as an extrapleural mass ansmg

from one or more ribs , cortical destruction or

expansion of the ribs , extensive mineralization

and some cyst-like portion within the mass , and

the patient age will aid in making the correct

diagnosis. CT is very helpful in the evaluation

of bony change of the ribs and the areas of

mineralization within hamartoma as well as its

extensIOn.

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Myung Joon Kim , et al : Multiple Hamartomas of the Unilateral Chest Wall in Infancy

REFERENCES

1. O akley RH , Carty H , Cudmore RE . Multiple

benign mesenchymomata of the ches wall

Pediatr Radiol 1985; 15: 58-60 2 . Brand T , Hatch EI , Schaller RT , StevensonJK ,

Arensman RM , Schwartz MZ. Surgical

management of the infant with mesenchymal

hamartoma of the chest well. J Pediatr Surg

1986;2 1 :556-558 3 Gwyther SJ , H all CM ‘ Mesenchymal hamar­

toma of the chest wall in infancy. C lin Radi이

1991 ;43:24-25 4. H opkins SM , Freitas EL. Bilateral osteochon­

droma of the ribs in an infant: An unusual cause

〈국문 요약〉

ofcyanosis.J Thorac and Cardiovasc Surg 1965; 49:247-249

5. McLeod RA , Dahlin DC . Hamartoma (mesen­

ch ymoma) of the chest wall in infancy.

Radiology 1979; 131:657 -66 1

6. Blumenthal BI , Capitanio MA , Queloz JM ,

Kirkpatrick JA. Intrathoracic mesenchymoma

Observations in two infats. Radiology 1972‘ 104:107-109

7. Schlesinger AE , Smith MB , Genez BM ,

M cMahon DP , Swaney JJ. C hest wall mesen­

chymoma (hamartoma) in infancy. CT and MR

findings. Pediatr R ad iol 1989; 19 ‘ 212-213 8 Campbell AN , Wagget J , Mott MG. Benign

mesenchymoma of the chest wall in infancy. J

Surg Oncol 1982;2 1‘ 267-270

유아의 펀측 흉벽에 발생한 다발성 과오종 (간엽종) : 전산화 단층 촬영 소견

연세대학교 의과대학 진단방사선과학교실， 병리학교실*

김영준 • 윤춘식 • 오기근 • 이종태 • 정우희*

소아의 늑골에서 발생하는 과오종(간엽종) 은 늑골 파괴 및 변형， 연조직 종괴등의 소견때문에 악성 골종양으로 오

인하거나 다발성으로 발생한 경우 전이성 병변으로 오진할 수 있는 드문 질환이다. 저자들은 4개월된 환아의 좌측

흉벽에 발생한 다발성 과오종의 단순 촬영， 골주사 및 전산화 단층촬영 소견을 병리소견과 함께 보고하며 특히 두 종

괴의 발병 위치와 전산화 단층 촬영 소견을 중심으로 문헌고찰과 함께 보고한다.

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