( 1992130. 398-400
I
I
1992 Thr
Glomus tumour of the palate: case report and review of the literature J. M. Gcraghty.
R. W. N. Thomas,
J. M. Robertson.
J. W. Blundell
Departments of Histopatholog-y und Osal ami Maxillofircial Surgery, Peterborough District Hospital, Peterborough, UK
Glomus tumours are benign vascular turnout-s, usually located in the skin. Intra-oral glomus SUMMARY. tumours are rare. A glomus tumour of the palate is reported, only the fifth such case out of a total of 14 intraoral glomus tumours in the world medical literature.
INTRODUCTION Glomus tumours arc circumscribed benign vascular lesions, usually located in the skin, and tend to be extremely painful. They are characterised by their content of so-called glomus cells, which resemble the modified smooth muscle cells of the normal glomus body, a specialised form of artcrio-venous anastamosis thought to play a role in local temperature regulation (Enzinger & Weiss, 1988). Simple excision is generally curative and subsequent recurrence exceptional. Extracutaneous glomus tumours have been described in various sites, including the mouth (Stajcic & Bojic, 1987). but arc rare. We describe a glomus tumour of the palate, to our knowledge only the fourteenth intra-oral glomus tumour documented in the world medical litcraturc.
Fig. I - Well-circumscribed vascular turnour in palatal subepithclial connective tissue. (H & E. Original magnification x 25)
Case report A 71-year-old Caucasian man prcscnted with a painless swelling of the palate which had enlarged slowly ovet several years. On examination. the lesion was a raised cream-coloured nodule, 1.5 cm in maximum dimension. situated in the hard palate, slightly to the right of the midline. Diagnoses including a minor salivary gland tumour and mucocoelc wcrc considered clinically. The lesion was excised under general anaesthesia. Healing occurred uneventfully over the subscqucnt weeks and there was no clinical evidence of rccurrcncc at ‘)-month review. Histological examination showed a well-circumscribed tumour lying within the palatal sub-epithelial connective tissue (Ftg. 1). The lesion was composed of numerous endothelium-lined dilated vascular channels surrounded by sheets of uniform round cells lying within a variable quantity of hyaline stroma (Fig. 2). The cells had centrally located, sharply dcfned, ‘punched-out’ nuclei and amphophilic cytoplasm (Fig. 3). There was neither nuclear pleomorphism nor mitotic activity. Electron microscopy revealed filamcntous material within the tumour cells, consistent with smooth muscle myofibrils. Viral particles and dense core granules were not seen. lmmunocytochemical staining for alpha actin, desmin and chromogranin wcrc negative in the tumour cells. Nerve fibres were not seen within the lesion on immunostaining with neuronc specific enolase (NSE) and protein gene product (PGP 9.5).
Fig. 2 - Endothelium-lined vascular channel surrounded by sheets of uniform round cells. (II & F.. Original magnification x 100).
DISCUSSION The uniform round cells described above are glomus cells, so named because of their resemblance to the specialised cells of the glomus bodies (Enzinger & Weiss, 1988). They have a highly distinctive appcarancc and in the context of a circumscribed vascular lesion arc diagnostic of a glomus tumour. Other vascular tumours such as cavernous haemangioma, 398
Glomus
Fig. 3 - Sheet ofcclls with central Original magnification x 250).
‘punch&out’
nuclei. (H & E.
epithelioid hacmangioma. pyogenic granuloma. angioleiomyoma and haemangiopericytoma lack glomus cells and can therefore be excluded from the diffcrential diagnosis on histological grounds alone. The theoretical possibility of an endocrine tumour can bc ruled out by the negative staining for chromogranin and the absence of dense cot-c granules on clcctron microscopy. The histological features arc not those of the clinical diagnoses of minor salivary gland tumour or mucocoele. In gcncral. glomus tumours arise in sites coincident with the distribution and concentration of glomus bodies (Enzinger & Weiss. 1988). The most frequent locations arc the subungual region of the fingers, the palm. wrist, forearm and foot. Glomus tumours arising in sites where glomus bodies are scanty or absent such as the oral cavity, gastro-intestinal tract, female genital tract. bone: chest vvall, face, lung and trachea have been reported but arc extremely rare (Stajcic & Bojic. 1987; Knzingcr & Weiss. 1988; Garcia-Rats et al.. 1991). To our knowledge. including our own case, I4 examples of intra-oral glomus tumours have been documented in the world literature (Stajcic & Bojic. 1987) located as follows: palate (5 cases), tongue (3 cases), buccal mucosa (2 cases) and one case each of gin&iv+ alveolar mucosa. periodonturn and lip. Like glomus tumours elsewhere, the intra-oral glomus tumours have shown no age or sex predcliction and have been solitary and benign without recurrence after excision (Stajcic & Bojic, 1987). The one possible exception was a glomus tumour of the tongue in which there was cellular atypia and mitotic activity suggestive of malignancy (Sat0 et ~1.. 1979). Unfortunately. there has been no published follow up on this case. However: other cases of glomus tumours showing histological features of malignancy (glomangiosarcomas) have not metastasised and it is therefore difficult to accept these extremely rare variants as true malignant tumours (Enzingcr & Weiss. 1988). Most intra-oral glomus tumours have been small Icsions. averaging I cm (Stajcic & Bojic, 1987). The present cast was slightly larger (I .5 cm), but there is no evidence that this feature alone affects prognosis. Glomus tumours located in the skin are characteris-
tumour
of the nalate
399
tically extremely painful. but this does not appear to be true of intra-oral glomus tumours (Stajcic & Bojic, 1987; Enzinger & Weiss, 1988). We challenge the explanation offered by Saku et (11. (1985) that the lack of pain relates to the loose texture of the intraoral tissues or mucoid dcgcncration of the tumour itself. In our case the lesion was painless yet there was no cvidcncc of mucoid change and the tumour was tightly bound in the palatal sub-epithelial connective tissue. The concentration of nerve fibrcs. high in cutaneous glomus tumours (Lever & SchaumburgLcvcr, 1990) but possibly lower or absent in those located clscwhcrc, might be important in this context. Tmmunostaining with NSE and PGP 9.5 did not demonstrate nerve fibres in the current lesion. The classic form of glomus tumour described in this report needs to be distinguished from the less common variants glomangioma and glomangiomyoma (Enzinger & Weiss, 1988). Glomangiomas arc poorly circumscribed and consist of gaping veins with rclativcly few glomus cells in their walls: they arc often familial and multiple. Glomangiomyomas show a prominent smooth muscle component, including transitional smooth muscle:‘glomus ccl1 forms, superimposed on the overall pattern of either an ordinary glomus tumour or a glomangioma. The intra-oral lesions described to date have been sinelc classic glomus tumours apart from a case of multYplc glomangiomas of the face, palate and eyelid (Charles, 1976) and the glomangiosarcoma of the tongue rcfcrrcd to above (Sate CI ul., 1979). The histogenesis of glomus tumours is unknown. Ultrastructurally the glomus cells show features of smooth muscle (Tsuncyoshi & Enjoji: 1982; Saku et trl.. 1985) in keeping with the electron microscopic findings described above. Alpha actin can usually be demonstrated immunocytochemically (Jones ef al.. 1990). The negative staining for this marker in the current lesion must represent a variation in staining pattern rather than disproving smooth muscle diffcrentiation or even casting doubt on the diagnosis itself. This is indeed the case with immunostaining for the muscle-type intermediate filament desmin which, as here, is frequently negative in glomus tumours (Jones et NI.. 1990). The glomus cells may be dcrivcd from a smooth muscle or vascular progenitor ccl1 (Saku rt al.. 1985) but the stimulus to glomus cell differentiation is uncertain. Glomus tumours might bc reactive in nature. developing as a response to disturbances in local haemodynamicst or true neoplasms, perhaps the result of infection by an oncogcnic virus. In this context, intracytoplasmic C type viral particles have been demonstrated in a glomus tumour of the tongue by electron microscopy (Sate et ai.. 1979). Viral particles wcrc not seen ultrastructurally in the present cast. Acknowledgement The authors
thank
Mr C. Burton
for photographic
assistance.
References Charles. X. C. (1976). Multiple glomus tumors of the fact and cyclid. Aw/~ivcc.\ 01 Ophrhaltwlog~. 94, 1283.
400
Hritish Journal
Enringer.
of Oral and Maxillofacial
F. M. & Weiss. W. W. (1988). Glomus
Surgery tumor.
In: Sofr
Tissue T7~?7ours. 2nd Ed.. pp 58 l-59.5. St Louis: The CV
Mosby Co. Garcia-Prats. M. D.. Sotclo-Rodriguez. M. T.. Rallcstin, C.. Martine/-Gonralez, M. A.. Rota, R.. Alfaro. J. & De Miguel. E. (1991). Glomus tumour of the trachea: report of a case with microscopic, ultrastructural and immunocytochemical examination and review of the literature. Ili.s/opcr/llolog~,. 19, 459. Jones. H.. Steart. P. V.. Du Roulay. C. E. II. & Rochc. W. R.. (1990). Alpha-smooth muscle actin as a marker for soft tissue wmours: A comparison aith desmin. Jou,nnl ofPnt/w/ogy. M&29. I.ever. W. F. & Schaumburf-Lc\;cr, G. (1990). Glomus tumor. In: His7opu/ho/u~~~ qf’hc Skin. 7th Ed.. pp 770-702. Philadelphia: JB Lippincott Co. Saku. T., Okabc. H.. Matsutani. K. & Sasaki, M. (1985). Glomus tumor of the cheek: An immunohistocheliiicnl demonstration of actin and myosin. Oral Surgqv, Owl Mrdicinc. Oral Pathulo~~. 60, 65. Sate. M.: Shirasuna, K.. Sakuda. M., Yanagawa. T.. Yoshida. H., Imai, J.. Maeda. N.. Kubo. K., Yura. Y., Miyazaki. T. & Yogi. T. (1979). Fine structure of a glomus tumor of the tongue and expression of C type virus in its tumor cells. 1~7ter~7ational Journul of Oral Surgery, 8, 199. Stajcic, Z. & Hojic. P. (1987). Intraoral glomus tumour: A cast report. Journal of (I.unio-Mu.riilo-l;ircicrl Surgq~. IS, 376.
Tsuneyoshi. M. & Enjoji. M. (1982). Glomus wmor. A clinicopathologic and electron microscopic study. Cancer. 50, 1601.
The Authors J. M. Geraghty B 4Jed SC, MBBS Senior Registrar Department of Histopathology I’. W. N. Thomas BDS Senior House Officer Department of Oral and Maxillofacial Surger! -1. Xl. Robertson .MBChB, BDS, FDSRCS Consultant Oral and Maxillofacial Surgeon J. W. Blundell BSc, MBBS, MRCPath Consultant I-Iistopathologisl Peterborough District Hospital Thorpe Road Peterborough PE3 6DI I Correspondence and quests for offprints to Dr J. M. Gcrdghty. Department of I-Iistopathology, Addcnbrooke‘s Hospital, Ilills Road. Cambridge. Paper received IO February Accepted 30 April 1992
1992
I
I
1992 Thr
Glomus tumour of the palate: case report and review of the literature J. M. Gcraghty.
R. W. N. Thomas,
J. M. Robertson.
J. W. Blundell
Departments of Histopatholog-y und Osal ami Maxillofircial Surgery, Peterborough District Hospital, Peterborough, UK
Glomus tumours are benign vascular turnout-s, usually located in the skin. Intra-oral glomus SUMMARY. tumours are rare. A glomus tumour of the palate is reported, only the fifth such case out of a total of 14 intraoral glomus tumours in the world medical literature.
INTRODUCTION Glomus tumours arc circumscribed benign vascular lesions, usually located in the skin, and tend to be extremely painful. They are characterised by their content of so-called glomus cells, which resemble the modified smooth muscle cells of the normal glomus body, a specialised form of artcrio-venous anastamosis thought to play a role in local temperature regulation (Enzinger & Weiss, 1988). Simple excision is generally curative and subsequent recurrence exceptional. Extracutaneous glomus tumours have been described in various sites, including the mouth (Stajcic & Bojic, 1987). but arc rare. We describe a glomus tumour of the palate, to our knowledge only the fourteenth intra-oral glomus tumour documented in the world medical litcraturc.
Fig. I - Well-circumscribed vascular turnour in palatal subepithclial connective tissue. (H & E. Original magnification x 25)
Case report A 71-year-old Caucasian man prcscnted with a painless swelling of the palate which had enlarged slowly ovet several years. On examination. the lesion was a raised cream-coloured nodule, 1.5 cm in maximum dimension. situated in the hard palate, slightly to the right of the midline. Diagnoses including a minor salivary gland tumour and mucocoelc wcrc considered clinically. The lesion was excised under general anaesthesia. Healing occurred uneventfully over the subscqucnt weeks and there was no clinical evidence of rccurrcncc at ‘)-month review. Histological examination showed a well-circumscribed tumour lying within the palatal sub-epithelial connective tissue (Ftg. 1). The lesion was composed of numerous endothelium-lined dilated vascular channels surrounded by sheets of uniform round cells lying within a variable quantity of hyaline stroma (Fig. 2). The cells had centrally located, sharply dcfned, ‘punched-out’ nuclei and amphophilic cytoplasm (Fig. 3). There was neither nuclear pleomorphism nor mitotic activity. Electron microscopy revealed filamcntous material within the tumour cells, consistent with smooth muscle myofibrils. Viral particles and dense core granules were not seen. lmmunocytochemical staining for alpha actin, desmin and chromogranin wcrc negative in the tumour cells. Nerve fibres were not seen within the lesion on immunostaining with neuronc specific enolase (NSE) and protein gene product (PGP 9.5).
Fig. 2 - Endothelium-lined vascular channel surrounded by sheets of uniform round cells. (II & F.. Original magnification x 100).
DISCUSSION The uniform round cells described above are glomus cells, so named because of their resemblance to the specialised cells of the glomus bodies (Enzinger & Weiss, 1988). They have a highly distinctive appcarancc and in the context of a circumscribed vascular lesion arc diagnostic of a glomus tumour. Other vascular tumours such as cavernous haemangioma, 398
Glomus
Fig. 3 - Sheet ofcclls with central Original magnification x 250).
‘punch&out’
nuclei. (H & E.
epithelioid hacmangioma. pyogenic granuloma. angioleiomyoma and haemangiopericytoma lack glomus cells and can therefore be excluded from the diffcrential diagnosis on histological grounds alone. The theoretical possibility of an endocrine tumour can bc ruled out by the negative staining for chromogranin and the absence of dense cot-c granules on clcctron microscopy. The histological features arc not those of the clinical diagnoses of minor salivary gland tumour or mucocoele. In gcncral. glomus tumours arise in sites coincident with the distribution and concentration of glomus bodies (Enzinger & Weiss. 1988). The most frequent locations arc the subungual region of the fingers, the palm. wrist, forearm and foot. Glomus tumours arising in sites where glomus bodies are scanty or absent such as the oral cavity, gastro-intestinal tract, female genital tract. bone: chest vvall, face, lung and trachea have been reported but arc extremely rare (Stajcic & Bojic. 1987; Knzingcr & Weiss. 1988; Garcia-Rats et al.. 1991). To our knowledge. including our own case, I4 examples of intra-oral glomus tumours have been documented in the world literature (Stajcic & Bojic. 1987) located as follows: palate (5 cases), tongue (3 cases), buccal mucosa (2 cases) and one case each of gin&iv+ alveolar mucosa. periodonturn and lip. Like glomus tumours elsewhere, the intra-oral glomus tumours have shown no age or sex predcliction and have been solitary and benign without recurrence after excision (Stajcic & Bojic, 1987). The one possible exception was a glomus tumour of the tongue in which there was cellular atypia and mitotic activity suggestive of malignancy (Sat0 et ~1.. 1979). Unfortunately. there has been no published follow up on this case. However: other cases of glomus tumours showing histological features of malignancy (glomangiosarcomas) have not metastasised and it is therefore difficult to accept these extremely rare variants as true malignant tumours (Enzingcr & Weiss. 1988). Most intra-oral glomus tumours have been small Icsions. averaging I cm (Stajcic & Bojic, 1987). The present cast was slightly larger (I .5 cm), but there is no evidence that this feature alone affects prognosis. Glomus tumours located in the skin are characteris-
tumour
of the nalate
399
tically extremely painful. but this does not appear to be true of intra-oral glomus tumours (Stajcic & Bojic, 1987; Enzinger & Weiss, 1988). We challenge the explanation offered by Saku et (11. (1985) that the lack of pain relates to the loose texture of the intraoral tissues or mucoid dcgcncration of the tumour itself. In our case the lesion was painless yet there was no cvidcncc of mucoid change and the tumour was tightly bound in the palatal sub-epithelial connective tissue. The concentration of nerve fibrcs. high in cutaneous glomus tumours (Lever & SchaumburgLcvcr, 1990) but possibly lower or absent in those located clscwhcrc, might be important in this context. Tmmunostaining with NSE and PGP 9.5 did not demonstrate nerve fibres in the current lesion. The classic form of glomus tumour described in this report needs to be distinguished from the less common variants glomangioma and glomangiomyoma (Enzinger & Weiss, 1988). Glomangiomas arc poorly circumscribed and consist of gaping veins with rclativcly few glomus cells in their walls: they arc often familial and multiple. Glomangiomyomas show a prominent smooth muscle component, including transitional smooth muscle:‘glomus ccl1 forms, superimposed on the overall pattern of either an ordinary glomus tumour or a glomangioma. The intra-oral lesions described to date have been sinelc classic glomus tumours apart from a case of multYplc glomangiomas of the face, palate and eyelid (Charles, 1976) and the glomangiosarcoma of the tongue rcfcrrcd to above (Sate CI ul., 1979). The histogenesis of glomus tumours is unknown. Ultrastructurally the glomus cells show features of smooth muscle (Tsuncyoshi & Enjoji: 1982; Saku et trl.. 1985) in keeping with the electron microscopic findings described above. Alpha actin can usually be demonstrated immunocytochemically (Jones ef al.. 1990). The negative staining for this marker in the current lesion must represent a variation in staining pattern rather than disproving smooth muscle diffcrentiation or even casting doubt on the diagnosis itself. This is indeed the case with immunostaining for the muscle-type intermediate filament desmin which, as here, is frequently negative in glomus tumours (Jones et NI.. 1990). The glomus cells may be dcrivcd from a smooth muscle or vascular progenitor ccl1 (Saku rt al.. 1985) but the stimulus to glomus cell differentiation is uncertain. Glomus tumours might bc reactive in nature. developing as a response to disturbances in local haemodynamicst or true neoplasms, perhaps the result of infection by an oncogcnic virus. In this context, intracytoplasmic C type viral particles have been demonstrated in a glomus tumour of the tongue by electron microscopy (Sate et ai.. 1979). Viral particles wcrc not seen ultrastructurally in the present cast. Acknowledgement The authors
thank
Mr C. Burton
for photographic
assistance.
References Charles. X. C. (1976). Multiple glomus tumors of the fact and cyclid. Aw/~ivcc.\ 01 Ophrhaltwlog~. 94, 1283.
400
Hritish Journal
Enringer.
of Oral and Maxillofacial
F. M. & Weiss. W. W. (1988). Glomus
Surgery tumor.
In: Sofr
Tissue T7~?7ours. 2nd Ed.. pp 58 l-59.5. St Louis: The CV
Mosby Co. Garcia-Prats. M. D.. Sotclo-Rodriguez. M. T.. Rallcstin, C.. Martine/-Gonralez, M. A.. Rota, R.. Alfaro. J. & De Miguel. E. (1991). Glomus tumour of the trachea: report of a case with microscopic, ultrastructural and immunocytochemical examination and review of the literature. Ili.s/opcr/llolog~,. 19, 459. Jones. H.. Steart. P. V.. Du Roulay. C. E. II. & Rochc. W. R.. (1990). Alpha-smooth muscle actin as a marker for soft tissue wmours: A comparison aith desmin. Jou,nnl ofPnt/w/ogy. M&29. I.ever. W. F. & Schaumburf-Lc\;cr, G. (1990). Glomus tumor. In: His7opu/ho/u~~~ qf’hc Skin. 7th Ed.. pp 770-702. Philadelphia: JB Lippincott Co. Saku. T., Okabc. H.. Matsutani. K. & Sasaki, M. (1985). Glomus tumor of the cheek: An immunohistocheliiicnl demonstration of actin and myosin. Oral Surgqv, Owl Mrdicinc. Oral Pathulo~~. 60, 65. Sate. M.: Shirasuna, K.. Sakuda. M., Yanagawa. T.. Yoshida. H., Imai, J.. Maeda. N.. Kubo. K., Yura. Y., Miyazaki. T. & Yogi. T. (1979). Fine structure of a glomus tumor of the tongue and expression of C type virus in its tumor cells. 1~7ter~7ational Journul of Oral Surgery, 8, 199. Stajcic, Z. & Hojic. P. (1987). Intraoral glomus tumour: A cast report. Journal of (I.unio-Mu.riilo-l;ircicrl Surgq~. IS, 376.
Tsuneyoshi. M. & Enjoji. M. (1982). Glomus wmor. A clinicopathologic and electron microscopic study. Cancer. 50, 1601.
The Authors J. M. Geraghty B 4Jed SC, MBBS Senior Registrar Department of Histopathology I’. W. N. Thomas BDS Senior House Officer Department of Oral and Maxillofacial Surger! -1. Xl. Robertson .MBChB, BDS, FDSRCS Consultant Oral and Maxillofacial Surgeon J. W. Blundell BSc, MBBS, MRCPath Consultant I-Iistopathologisl Peterborough District Hospital Thorpe Road Peterborough PE3 6DI I Correspondence and quests for offprints to Dr J. M. Gcrdghty. Department of I-Iistopathology, Addcnbrooke‘s Hospital, Ilills Road. Cambridge. Paper received IO February Accepted 30 April 1992
1992
