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Congenital myoblastoma of the newborn
CONGENITAL JAMES
MYOBLASTOMA
R. HAYWARD,
OF THE
NEWBORN
D.D.S., MS., ANN ARBOR,
MICH.
its description by Abrikossoff in 1926, myoblastoma as a tumor enSINCE tity has received increasing attention. Several comprehensive reviews appear in the literature: Klemperer in 1934, Gray and Gruenfeld in 193’7, Horn and Stout in 1943, and Crane and Tremblay in 1945. The last review compiled 162 cases with a wide variety of locations of tumor. The tongue, lips, and jaws are relatively common sites, while myoblastomas have also been found in the larynx, upper esophagus, skin, orbit, external auditory canal, breast, and muscles of the extremities. The most common site of origin is the tongue where 38 per cent of the reported cases appeared. These tumors have been found in all age groups. The myoblastomas on the maxilla were all found in the newborn. Before the clarification of myoblastomas these tumors of the alveolar ridge were called “congenital epulis of the newborn.” They appear as pedunculated sessile masses on the anterior maxillary alveolar process in the region of the incisor teeth (Fig. 3). Crane and Tremblay reported a case with three distinct tumors in this location. Reviews of the literature indicate that this congenital epulis form comprises about 10 per cent of the reported myoblastomas. The histopathologic features of the tumor are characterized by large polyhedral cells 20 to 60 micra in diameter with small distinct nuclei and a coarse neutrophilic granular cytoplasm (Fig. 1). Their foamy appearance suggests xanthomatous t,umors (Fig. 2). This possibility is ruled out in differential diagnosis by failure of the myoblastoma foam cells to take the specific lipoid stains used to identify xanthomas. The myoblastoma tumor cells are surrounded by a slender connective tissue network. The tumor cells are thought to resemble embryonal skeletal muscle. A unique feature of the myoblastoma in the tongue is the blending of tumor cells and normal striated muscle cells. This appearance of intimate transition leads some investigators to believe that the tumor arose from a necrotic degenerative change in muscle. The transit,iona,l features of myoblastoma in the tongue are not seen in other locations where they are often encapsulated. The most widely accepted theory of origin of myoblastoma is a dysontogenesis of embryonal skeletal muscle. Upon tissue culture Stout has found that the metabolic activity of these tumors suggests muscle derivation. However, the origin of the nonlingual myoblastomas is still undetermined and open to question. Fust and Custer in 1949 reviewed 35 tumors originally diagnosed as granular cell myoblastoma. As a result of their investigations they advanced a neurogenic theory for the origin From
the Department
of Oral
Surgery,
School 667
of Dentistry,
University
of Michigan.
668
.T:\RIES
M.
I1AY\\'ARU
oc re Nl gr to
Fig. Fig. l.-Section from the periphery of let- t and the typical large polyhedral granular Fig. 2.-High-power detail of the tumor foa my granular cytoplasm.
2.
the
tumor showing the epithelial surface 01 the cells of myoblastoma. cells showing their distinct eccentric nuclei anrl
CONGENITAL
MYOBIASTORIA
OF
669
NEWBORK
An interesting feature of myoblastoma of the tongue, larynx, and skin is Such pseudoepitheliomatous the proliferation of the overlying epithelium. hyperplasia gives the appearance of carcinoma, and a superficial biopsy of such a lesion can be very misleading. The general behavior of myoblastoma is benign, although the immature appearance of the tumor cell would suggest otherwise. There is often a long history of tumor duration before excision, and recurrences following removal are not common. The rrlat.ed malignant counterpart of tumors in this group is the rhabdomyosarcoma. In a reported case there was persistence Myoblastomas are radioresistant. of the tumor, while radium therapy to the area had produced necrosis of the surrounding normal tissues. Excision is the treatment of choice.
Case Report M. M., a full-term healthy infant girl, presented a congenital tumor of the anterior maxillary alveolar ridge (Fig. 3). The child showe~l no other corrgenital anomalies and none wre revealed in the family history. TYO older sil)lings were normal, living and well.
Fig.
RR. Fig.
3.-Clinkal 4.-The
3.
Fig.
appearance of the maxillary excised and bisecte(l tumor mass
ridge tumor. on a 2 by 2 inch
4.
gauze
sponge.
Examination of the tumor showed a pedunculated mass, 1 i)y 0.5 cm., just to the left of the midline. The alveolar ridge was depressed beneath the tumor. The mass interfered with normal infant feeding. The. surface of the tumor was smooth and normal, and it was firm am1 sessile to palpation. Since the infant was in gootl condition sonn twenty hours after birth, the tumor was excised immediately. The basal defect was closed with several chromic gut sutures. II~w~ostasis was prompt and healing uneventful. Upon section the tumor was pellowgr:ry in color, homogeneous and firm in consistency (Fig. 4). Pathologic diagnosis was granular cell myoblastoma. The followup
infant gained weight examination six months
and left the later revealed
hospital with her mother no evidence of recurrence.
after
five
days.
Comment Another case of granular gingjval tumor is reported.
cell myoblastoma in the form of a congenital location, clinical appearance, and histo-
The
A
670
.JAiltES
R.
HAYWARD
pathologic l)ictltrc art typical of this tnmo~* entity. Jt is unusual to find 011cologic problems in the 11ew1wr~~. ‘l’hc cksnct, classifiration of this tumor is still opeli to question,
References Crane, A. B., and Tremblay, X. U.: Am. .I. Path. 21: XT 1%43. Fust,, J. A., and Custer, R. P.: Am. .J. Clin. Path. 19: .522: 1949. Gray, S. H., and Gruenfeld, G. E.: Am. J. Cancer 30: 399, 1937. Horn, R. C., and Stout, A. P.: Surg., Gynec. & Obst. 76: 31.5, 1913. Klemperer, Paul : Am. J. Cancer 20: 324, 1934. Stout, A. P.: Comments in the Proceedings of the Arthur I’urdy May, 1951.
Stout
Clul)
Seminar,
MYOBLASTOMA
R. HAYWARD,
OF THE
NEWBORN
D.D.S., MS., ANN ARBOR,
MICH.
its description by Abrikossoff in 1926, myoblastoma as a tumor enSINCE tity has received increasing attention. Several comprehensive reviews appear in the literature: Klemperer in 1934, Gray and Gruenfeld in 193’7, Horn and Stout in 1943, and Crane and Tremblay in 1945. The last review compiled 162 cases with a wide variety of locations of tumor. The tongue, lips, and jaws are relatively common sites, while myoblastomas have also been found in the larynx, upper esophagus, skin, orbit, external auditory canal, breast, and muscles of the extremities. The most common site of origin is the tongue where 38 per cent of the reported cases appeared. These tumors have been found in all age groups. The myoblastomas on the maxilla were all found in the newborn. Before the clarification of myoblastomas these tumors of the alveolar ridge were called “congenital epulis of the newborn.” They appear as pedunculated sessile masses on the anterior maxillary alveolar process in the region of the incisor teeth (Fig. 3). Crane and Tremblay reported a case with three distinct tumors in this location. Reviews of the literature indicate that this congenital epulis form comprises about 10 per cent of the reported myoblastomas. The histopathologic features of the tumor are characterized by large polyhedral cells 20 to 60 micra in diameter with small distinct nuclei and a coarse neutrophilic granular cytoplasm (Fig. 1). Their foamy appearance suggests xanthomatous t,umors (Fig. 2). This possibility is ruled out in differential diagnosis by failure of the myoblastoma foam cells to take the specific lipoid stains used to identify xanthomas. The myoblastoma tumor cells are surrounded by a slender connective tissue network. The tumor cells are thought to resemble embryonal skeletal muscle. A unique feature of the myoblastoma in the tongue is the blending of tumor cells and normal striated muscle cells. This appearance of intimate transition leads some investigators to believe that the tumor arose from a necrotic degenerative change in muscle. The transit,iona,l features of myoblastoma in the tongue are not seen in other locations where they are often encapsulated. The most widely accepted theory of origin of myoblastoma is a dysontogenesis of embryonal skeletal muscle. Upon tissue culture Stout has found that the metabolic activity of these tumors suggests muscle derivation. However, the origin of the nonlingual myoblastomas is still undetermined and open to question. Fust and Custer in 1949 reviewed 35 tumors originally diagnosed as granular cell myoblastoma. As a result of their investigations they advanced a neurogenic theory for the origin From
the Department
of Oral
Surgery,
School 667
of Dentistry,
University
of Michigan.
668
.T:\RIES
M.
I1AY\\'ARU
oc re Nl gr to
Fig. Fig. l.-Section from the periphery of let- t and the typical large polyhedral granular Fig. 2.-High-power detail of the tumor foa my granular cytoplasm.
2.
the
tumor showing the epithelial surface 01 the cells of myoblastoma. cells showing their distinct eccentric nuclei anrl
CONGENITAL
MYOBIASTORIA
OF
669
NEWBORK
An interesting feature of myoblastoma of the tongue, larynx, and skin is Such pseudoepitheliomatous the proliferation of the overlying epithelium. hyperplasia gives the appearance of carcinoma, and a superficial biopsy of such a lesion can be very misleading. The general behavior of myoblastoma is benign, although the immature appearance of the tumor cell would suggest otherwise. There is often a long history of tumor duration before excision, and recurrences following removal are not common. The rrlat.ed malignant counterpart of tumors in this group is the rhabdomyosarcoma. In a reported case there was persistence Myoblastomas are radioresistant. of the tumor, while radium therapy to the area had produced necrosis of the surrounding normal tissues. Excision is the treatment of choice.
Case Report M. M., a full-term healthy infant girl, presented a congenital tumor of the anterior maxillary alveolar ridge (Fig. 3). The child showe~l no other corrgenital anomalies and none wre revealed in the family history. TYO older sil)lings were normal, living and well.
Fig.
RR. Fig.
3.-Clinkal 4.-The
3.
Fig.
appearance of the maxillary excised and bisecte(l tumor mass
ridge tumor. on a 2 by 2 inch
4.
gauze
sponge.
Examination of the tumor showed a pedunculated mass, 1 i)y 0.5 cm., just to the left of the midline. The alveolar ridge was depressed beneath the tumor. The mass interfered with normal infant feeding. The. surface of the tumor was smooth and normal, and it was firm am1 sessile to palpation. Since the infant was in gootl condition sonn twenty hours after birth, the tumor was excised immediately. The basal defect was closed with several chromic gut sutures. II~w~ostasis was prompt and healing uneventful. Upon section the tumor was pellowgr:ry in color, homogeneous and firm in consistency (Fig. 4). Pathologic diagnosis was granular cell myoblastoma. The followup
infant gained weight examination six months
and left the later revealed
hospital with her mother no evidence of recurrence.
after
five
days.
Comment Another case of granular gingjval tumor is reported.
cell myoblastoma in the form of a congenital location, clinical appearance, and histo-
The
A
670
.JAiltES
R.
HAYWARD
pathologic l)ictltrc art typical of this tnmo~* entity. Jt is unusual to find 011cologic problems in the 11ew1wr~~. ‘l’hc cksnct, classifiration of this tumor is still opeli to question,
References Crane, A. B., and Tremblay, X. U.: Am. .I. Path. 21: XT 1%43. Fust,, J. A., and Custer, R. P.: Am. .J. Clin. Path. 19: .522: 1949. Gray, S. H., and Gruenfeld, G. E.: Am. J. Cancer 30: 399, 1937. Horn, R. C., and Stout, A. P.: Surg., Gynec. & Obst. 76: 31.5, 1913. Klemperer, Paul : Am. J. Cancer 20: 324, 1934. Stout, A. P.: Comments in the Proceedings of the Arthur I’urdy May, 1951.
Stout
Clul)
Seminar,