Case Report of Heterotopic Bone Formation in Metastatic Carcinoma of the Colon

The case of an 83-year-old woman, who was operated on for an adenocarcinoma of the sigmoid colon and died with retroperitoneal metastases, is described. The postmortem examination showed widespread heterotopic bone formation in these metastases. Gastrointestinal cancers and their metastases are liable to calcify and ossify, and they do so more frequently than other malignant epithelial tumors. A search through the literature led to the discovery of 35 other cases of this type. The highest frequency of heterotopic bone formation occurs in cancers of the distal portion of the large intestine and in pulmonary and lymph node metastases. The results of the present case support the view that bone formation derives from the metaplasia of stromal fibroblasts into osteoblasts. The knowledge that gastrointestinal cancers can calcify and ossify has a definite diagnostic relevance for the radiologist and gastroenterologist.

Recurring phyllodes tumor in aberrant breast tissue of the vulva

A 20-year-old nulligravida woman presented with bilateral cystic nodules of the vulva, diagnosed after simple excision as benign phyllodes tumor. Breast tissue, which also displayed fibrocystic changes, was also recognized. Follow-up at 2 months revealed no evidence of disease; however, 8 months after surgery she returned with a new mass in the vulva. This was excised and found to be recurrent phyllodes tumor. Although somewhat more cellular than the first lesions, it also was deemed to be benign based on histological features supported by flow cytometric DNA studies.

Ectopic cervical hamartomatous thymoma showing extensive myoid differentiation

Ectopic 'hamartomatous' thymoma is a rare benign neoplasm. These tumours are found in the neck and are thought to be part of a spectrum of ectopic cervical thymic neoplasia. The clinical and histological features are discussed and the literature is reviewed. An attempt is made to explain in embryological terms why such lesions appear to occur more commonly on the left side.

Phakomatous choristoma of the eyelid. Immunohistochemical and electron microscopic observations

BACKGROUND

A 13-month-old Hispanic boy underwent excision of a congenital inferonasal orbital mass arising from the right lower lid. Results of histopathologic examination of the tumor showed a phakomatous choristoma of the eyelid. An immunohistochemical and electron microscopic study of this rare, benign, congenital tumor of lenticular anlage was performed.

METHODS

Immunohistochemistry was performed on 4-microns thick sections from paraffin-embedded tissue. Electron microscopy was performed on thin sections stained with uranyl acetate and lead citrate.

FINDINGS

The cuboidal epithelial cells that comprise this choristoma showed strongly positive cytoplasmic staining with S-100 protein and vimentin and focally positive staining with a keratin cocktail (AE1/AE3). Electron microscopy showed the presence of numerous 10-nm whorled cytoplasmic microfilaments within degenerating epithelial cells.

CONCLUSION

The immunoreactivity of this tumor to keratin and vimentin are newly described in this detailed clinicopathologic report and, together with its S-100 positivity, support the proposal that this tumor is of lenticular anlage. The authors hypothesize that the intracytoplasmic 10-nm intermediate filaments observed with electron microscopic examination within the epithelial cells that comprise this choristoma represent vimentin as detected by immunohistochemistry.

Follicular carcinoma with clear cell change arising in lingual thyroid

A case of follicular carcinoma arising in the lingual thyroid of a 23-year-old woman is added to the 22 previous reports. The embryology and the clinical and pathologic differential diagnoses are discussed. Histologic criteria useful in diagnosing follicular malignancy in this area include local and vascular invasiveness, hypercellularity, mitotic activity, and necrosis. The use of the immunohistochemical marker thyroglobulin and electron microscopy are described for the first time and confirm a thyroid follicular cell origin.

Cutaneous ganglion cell choristoma. Report of a case

We describe the histological, immunohistochemical, and ultrastructural findings of a cutaneous tumour composed of ganglion cells, without any other proliferating component. As ganglion cells are not normal components of the skin, we propose the term "ganglion cell choristoma" for this lesion. The differential diagnosis of related lesions such as cutaneous ganglioneuroma, well-differentiated metastases from neuroblastoma, autonomic ganglia entrapped by neurofibroma, and reactive processes, and the possible histogenesis of ganglion cell choristoma are discussed.

SEM contribution to the morphological study of dental structures in ovarian cystic teratoma

This study in scanning electron microscopy (SEM) was carried out to observe the possible pathologic aspect of five teeth grossly arranged in normal sequence and of their surrounding tissues, found inside an ovarian cystic teratoma. Though the general morphology of the teeth was nearly normal, several anomalies affected the different mineralized dental tissues such as enamel hypoplasia, irregular growth of cementum, altered predentin layer, and immature osteofibrous bony outgrowths.

Phakomatous choristoma: clinical, histopathologic, and ultrastructural findings in a 4-month-old boy

A case of phakomatous choristoma of the lower eyelid is described. A survey of previously reported cases reveals a characteristic and consistent clinical and morphologic picture. Universally the patient presents in infancy with a rather small, firm, rubbery nodule attached to the lower edge of the inferior tarsal plate. Always present in the nasal aspect of the lower lid, the tumor is easily palpable. Recognition of this clinical picture may allow the ophthalmologist to suspect the appropriate diagnosis, but the final diagnosis should be based on the recognition of characteristic histopathology.

Exocrine pancreatic tissue in human liver: a metaplastic process?

Numerous microscopic foci of exocrine pancreatic tissue consisting of acini and small ductules were distributed throughout the liver of a 41-year-old patient with severe posthepatitic cirrhosis. The acinar cells were characterized by abundant zymogen granules on electron microscopic examination and a strong reaction with antibodies to alpha-amylase on immunoperoxidase staining. The pancreatic tissue was associated with proliferations of bile ductules within areas of fibrosis. No relationship with hepatocytes was observed. A metaplastic origin of the pancreatic tissue from the intrahepatic biliary epithelium is suggested.

Adrenal cortical adenoma in the spinal canal of an 8-year-old girl

An ectopic adrenal cortical adenoma containing high levels of androstenedione but without clinically detectable virilizing effects was found in the spinal intradural space of an 8-year-old girl. The tumor, which was located at the L2 level, manifested itself clinically by a short history of bilateral leg pain. It was well encapsulated; therefore, total surgical removal was accomplished. The light microscopic appearance of the tumor was typical of adenomatous adrenal cortical tissue. Ultrastructurally, it also showed characteristic features of steroid-producing tumors, including very abundant smooth endoplasmic reticulum and giant mitochondria with tubulovesicular and circular cristae. Frozen tissue analyzed by radioimmunoassay was found to contain almost 20 times the normal tissue level of androstenedione. There was no elevation of cortisol or aldosterone levels in the tumor. Postoperative magnetic resonance imaging (MRI) scan of the retroperitoneum showed no abnormalities in the patient's adrenal glands. Serum androstenedione levels were normal. We postulate that the adenoma developed from congenital ectopic rests of intraspinal adrenal tissue. Although ectopic occurrence of adrenal cortical tissue has been recorded in other areas, neither such rests nor tumors developing from them have been previously reported within the spinal canal.

Heterotopic gastric mucosa of the small intestine in laboratory beagle dogs

Out of the 365 young laboratory beagle dogs which were used in 17 toxicity bioassays, 15 cases (4.1%) were diagnosed as having congenital heterotopic gastric mucosa of the small intestine. Its incidence in the male dogs (12 cases out of 187) was higher than in the female dogs (3 cases out of 178). Grossly, the lesions were seen as an ulcerous focus of the small intestine, 25 cm to 88 cm proximal to the ileocecal valve. All of the lesions were quite similar histologically and electron microscopically to the normal gastric mucosa, which are composed of the surface mucous cells, chief cells, parietal cells, mucous neck cells and basal granulated cells of the stomach. And consequently, they were considered to be that of a congenital heterotopic tissue in the small intestine. The only morphological characteristic of these lesions different from the regular gastric mucosa was an association with the tubular structure seen in the basal region of these mucosal layers. These cells were considered to be of mucous-secreting cell origin because of secreting type III mucous evident from paradoxical concanavalin A or periodic acid Schiff stains. They seemed to be protecting the surrounding intestinal mucosa from gastric acid.

Phakomatous choristoma of the lower eyelid. A light and ultrastructural study

This article documents the eighth reported case (to our knowledge) of a phakomatous choristoma, a rare congenital tumor of the lower eyelid of infants. Among the eight cases, there was no instance of tumor recurrence recorded nor was there any detectable postoperative eye defect, despite incomplete resection of the tumor in two patients. While usually clinically diagnosed as a dermoid cyst, the highly characteristic histologic features of this entity should allow more frequent recognition. Ultrastructural examination in our case provided additional evidence of its lenticular origin.

Fine needle aspiration cytology of recurrent ectopic meningioma

Fine needle aspiration was performed on a recurrent extracranial meningioma in the left pterygomaxillary and temporal fossas in a 39-year-old woman. Cytologic and electron microscopic study of the aspirate and comparison to the previously resected specimen proved the recurrent nature of the lesion. The cytologic and ultrastructural findings in meningiomas are discussed with special consideration of the differential diagnosis in extracranial sites.

Extrameningeal meningiomas of the infratemporal fossa: diagnosis and treatment

A presentation of two recently treated extrameningeal meningiomas of the infratemporal fossa will be augmented by a review of the literature on this subject. These tumors are quite rare, insidious in their presentation, and, as a benign tumor, require consideration of surgical treatment which causes the least possible functional disability. The natural history of these lesions and the surgical approach which has proved most successful in our hands will be discussed in some detail.

Adenocarcinoma of the upper esophagus arising in ectopic gastric mucosa. Two case reports and review of the literature

Although ectopic gastric mucosa is often mentioned as a source of upper esophageal adenocarcinoma, few such cases have actually been documented. We report two cases and offer a review of the literature. Ectopic gastric mucosa in the upper esophagus is a relatively common congenital condition, but the risk of malignant transformation is extremely low. Ectopic gastric mucosa should be distinguished from Barrett's esophagus, an acquired condition with a well-documented predilection for developing adenocarcinoma.

Intracardiac ectopic thyroid

The case of a patient with an intracardiac ectopic thyroid is reported. A lesion was found in a 25-year-old man and was diagnosed by two-dimensional echocardiography as a right intraventricular tumor. An operation was performed. Histologic and ultrastructural studies showed that the tumor was a thyroid mass. The origin of intracardiac ectopic thyroids is probably to be found in disturbances occurring early in embryogenesis.

Heterotopic smooth muscle in the choroid of two patients with cryptophthalmos

The mode of inheritance in the complete cryptophthalmic syndrome is not clear in all cases. In two of our patients with complete cryptophthalmos, one showed a probable autosomal-recessive inheritance, while in the other patient, the mode of transmission could not be determined. Light and electron microscopic studies of the globes demonstrated heterotopic smooth-muscle tissue in the anterior part of the choroid in these two patients. Although these findings might be explained on the basis of a lack of directional growth of the embryonic ciliary muscle cells during the early embryonic period, we favor a simple anatomical explanation based on differentiation arrest of the anterior segment. During the fourth month of gestation, the growing optic cup presumably fails to advance forward normally and to differentiate. The relatively normally developing posterior segment extends posteriorly. The "stretching" backward of the ora serrata during the seventh month of gestation "drags" with it the ciliary smooth muscle that did not advance forward due to the earlier arrest. Thus, in the definite cryptophthalmic eye, the smooth-muscle tissue is localized within the anterior choroid.

Aortic body tumour with adjacent ectopic thyroid tissue in a dog

A 12-year-old neutered male Husky dog had a neoplasm at the base of the heart which did not invade surrounding tissues. Microscopically, the neoplasm was composed of nests and sheets of polyhedral cells subdivided into lobules by trabeculae of fine fibrovascular stroma. Adjacent to the neoplasm was a rim of ectopic thyroid tissue that appeared histologically normal. The possible differential diagnoses for the neoplasm were aortic body tumour, ectopic thyroid tumour and ectopic parathyroid tumour; the ultrastructural characteristics revealed it to be an aortic body tumour.

Ectopic brain in the orbit

We report a case of ectopic brain tissue in the orbit associated with a bony defect of the orbit and the presence of skeletal muscle. Previous reports of orbital ectopic brain and related lesions in the orbit and at other sites are reviewed.

Ectopic Purkinje cells in the cerebellar white matter of normal adult rodents: a Golgi study

In Golgi/Río-Hortega preparations of rat and rabbit cerebellar vermis we have occasionally found isolated ectopic Purkinje cells in the white matter. They were located beneath the bases of the folia and their dendritic branches extended within the confines of the white matter without penetrating into the overlying cortical layers. The general morphology of these ectopic cells was variable, particularly in the extension and shape of the dendritic trees, but all of them exhibited a lower density of dendritic branches than normal Purkinje cells. The less-developed ectopic neurons had multipolar dendritic trees with nonplanar branches irregularly studded with spines. The well-developed ones displayed a more extensive arborization of their processes and they usually preserved some morphological features of normal cortical Purkinje cells: distal dendritic branches studded with numerous spines, a pear-shaped soma, clearly defined morphological polarity and a tendency to display planar arrangement of the dendritic arbors. In semithin sections these neurons also showed cytological features of normal Purkinje cells, such as the Nissl substance forming a nuclear cap oriented toward the dendritic pole. We suggest that the abnormal location of the neurons results from a disorder of Purkinje cell migration which occurs naturally during the prenatal development of the cerebellum. The possible morphogenetic mechanisms involved in the migration and differentiation of these ectopic neurons are also discussed.

Heterotopic gastric mucosa: a case report

A case of heterotopic gastric mucosa in discrete nodules of the duodenum is presented. Its radiographic and endoscopic appearance is described. The light and electron microscopic features are analyzed. Ultrastructural examination of its organization, cellular and subcellular components revealed similarities to normal fundic gastric mucosa. The histological and clinical differences between heterotopic gastric mucosa and duodenal metaplastic change are discussed.

[Heterotopic smooth muscle in the choroid]

A histological and ultrastructural description of a case with an area of smooth muscle in the choroid of both eyes in presented. This was a chance finding in the globes of a deceased female patient whose lids (OU) as well as the conjunctiva and sclera of one side were affected by mycosis fungoides. The heterotopic smooth muscle in the choroid is interpreted as being an isolated malformation in otherwise nondysplastic eyes. It is possible that the rare leiomyomas of the choroid occur in such heterotopias, which have not been observed before.

Ectopic thyroid carcinoma with metastases in a beagle dog

A 10.25-year-old female beagle had an invasive neoplasm at the base of the heart which metastasized to the lungs, pancreas, and kidney. The neoplasm in these locations was composed of clusters of polyhedral cells surrounded by fine fibrovascular stroma. The differential diagnoses were malignant chemodectoma, ectopic parathyroid carcinoma, and ectopic thyroid carcinoma. Based on ultrastructural features, this tumor was an ectopic thyroid carcinoma.

Phakomatous choristoma of the lower eyelid with psammoma body formation: a light and electron microscopic study

A firm, round tissue mass, measuring approximately 12 mm in diameter, was excised from a 5-month-old boy who had a history of a gradually enlarging swelling in the left lower nasal eyelid since birth. Histologically and ultrastructurally, the lesion appeared benign and was composed of a dense connective tissue stroma in which nests, lobules, tubules, cords, and sheets of large, pale-staining cuboidal and elongated epithelial cells were surrounded by an irregular, thick PAS-positive basement membrane having focal excrescences. The interior of the epithelial islands contained "bladder" cells, cellular debris, granuloamorphous material, and foci of dystrophic calcification; an unusual feature of the lesion was the formation of numerous psammoma bodies. Tumors of lenticular anlage are rare and probably result due to displacement of migration of the inferior lens placode cells; alternatively, it may originate from an additional locus of lens vesicle in the primitive surface ectoderm of the lower lid. The lesion enlarges because of the differentiation of the ectopic lenticular cells in an abortive attempt to form a lens within the extraocular and mesodermal environment of the lid.

An unusual case of heterotopic pancreas of the stomach

A 56 year old man had an unusual case of heterotopic pancreas of the stomach. The patient had two lesions. One was at the gastroesophageal junction, representing the highest location in the stomach reported for this lesion. The second lesion was in the prepyloric antrum and consisted of heterotopic pancreatic tissue as well as tissue consistent with heterotopic ampulla of Vater. A general review of heterotopic pancreas is presented.

Microfilaments in cells associated with induced heterotopic bone formation in guinea pigs. An immunofluorescence and ultrastructural study

Sera from patients with active chronic hepatitis were used to demonstrate actin microfilaments in cells of a bone-induced model. Demineralized and freeze-dried allogenic dentine was implanted in the abdominal muscles of Guinea pigs. After 21 and 28 days the tissue was excised and showed: a) resorption areas of the dentine contained dentinoclasts and macrophages. b) osteoid and bone and c) areas of fibroblastic proliferation. Osteoblasts and young osteocytes showed the strongest fluorescent staining. Electron microscopy of these cells demonstrated abundant 5-7 nm microfilaments interpreted as actin in the outer parts and cell projections, in which some microtubules also were observed. Fewer microfilaments were present in mature osteocytes although the cell projections in mineralized bone also showed microfilaments. Microfilaments were also found in some dentinoclasts where the actin was located in projections from the ruffled border protruding into the dentine. The localization in the ruffled border corresponded to the distribution of the fluorescent staining of actin. The high amount of actin in osteoblasts and osteocytes may be correlated to the synthesis and transport of the new matrix components. The microfilaments in the clear sealing zone of dentinoclasts were considered to have a function in the sealing of the ruffled border.

Heterotopic gastric epithelium in the head and neck region

Heterotopic gastric epithelium in the head and neck area is a little-known entity, unsuspected by clinician and pathologist alike. We have reviewed the literature and discovered 14 cases of this entity. While previous reviews of the subject have, unfortunately, included reports of cases with heterotopic intestinal epithelium, our study addresses itself to separating the two. Five new cases of gastric heterotopia are reported in 3 female and 2 male patients ranging in age from 2 1/2 weeks to 70 years. Three cystic lesions occurred in the floor of the mouth, while 2 small nudular lesions were found in the region of the larynx. The larger lesions caused obstructive symptoms. An error in embryogenesis is the only plausible explanation for such heterotopic elements as gastric fundic, antral, and mucous neck types of epithelium, often associated with a partial muscularis mucosae, in the head and neck region. Treatment consists of surgical extirpation.

Myelolipoma in a heterotopic adrenal gland: light and electron microscopic findings

A symptomatic myelolipoma of the heterotopic adrenal gland was diagnosed as the cause of nephrotic syndrome and was surgically removed. Remission of the nephrotic syndrome promptly ensued. Ultrastructurally, the tumor consisted of well-differentiated cells resembling adrenal cortical cells, bone marrow cells in various stages of differentiation, and lipid cells. Some cells that contained fat were of adrenal cortical origin, but the derivation of most lipid cells and of bone marrow elements could not be deduced from the present ultrastructural findings.

Ovarian hilus cell heterotopia

A systematic pathologic study was done of the paratubal and parametrial tissues, submitted along with distal tubal segments excised for sterilization and with uteri (with or without attached adnexa) removed for common gynecologic conditions. Heterotopic ovarian hilus cell rests were noted in 12 cases, giving an overall incidence of 0.52% (12/2299). These cell rests, confined exclusively to the endosalpinx and perisalpinx, were easily differentiated from pregnancy-related decidual nodules, Walthard rests, foci of paratubal endometriosis, and ectopic adrenal rests.

Melanotic neuroectodermal tumor of infancy with highly differentiated neural component. Light and electron microscopic study

A pigmented tumor was removed from the maxillar alveolar process of a 5-month-old boy. It was examined by light and electron microscopy and a diagnosis of melanotic neuroectodermal tumor was made. In addition to connective tissue, three main cell types were identified: undifferentiated (stem) cells, melanocytes, and nerve cells with processes forming an abundant neuropil. Numerous axo-dendritic and occasional axo-somatic synapses were observed. The neural component demonstrated better differentiation in this example than in any reported so far.

Gastric heterotopia in the ileum causing hemorrhage

Two cases of infants with heterotopic gastric mucosa in the ileum causing hemorrhage and massive bleeding per rectum are presented. Preoperative Technetium 99 m scanning was valuable as a means to the diagnosis. Successful operative treatment was achieved by segmental resection with end to end anastomosis.

[Peri-navel intestinal patch-like choristia (author's transl)]

The authors describe an umbilical anomaly marked by confluent erythematous and crusted plaques, spreading beyond the navel limits and histologically regarded as a choristia that is to say a displacement of intestinal tissue within the epidermis. The ultrastructural study investigated the relationship between intestinal cells and keratinocytes. The authors believe that behaviour analogies exist between ectopic intestinal cells and Paget's cells.