Nasopharyngeal fibroma: causes, symptoms, diagnosis, treatment

Nasopharyngeal fibroma is a fibrous tumor of dense consistency, characterized by significant bleeding, which is why it is called angiofibroma. This tumor has been known since the time of Hippocrates, who proposed the so-called transnasomedial approach by bifurcating the nasal pyramid to remove this tumor.

The site of tumor origin is most often the vault of the nasopharynx, its pharyngeal-basal fascia (basilar tumor type, according to A. Glikhachev, 1954). Research in the last years of the 20th century showed the possibility of development of juvenile nasopharyngeal fibromas from the pterygomaxillary and sphenoid-ethmoidal regions.

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What causes nasopharyngeal fibroma?

The etiology of this disease is practically unknown. The existing "theories" of dysembryogenesis and endocrine dysfunction have not fully resolved the problem. The "endocrine theory" is based on the fact that the tumor develops simultaneously with the development of secondary sexual characteristics and the period of its development ends with the end of puberty. It has also been noted that with nasopharyngeal fibroma, there are violations of the secretion of 17-ketosteroids and the ratio of androsterone and testosterone.

Pathological anatomy of nasopharyngeal fibroma

Nasopharyngeal fibroma is a very dense tumor sitting on a wide base, tightly fused with the periosteum. The strength of the fusion with the periosteum is so great that in other cases, when removing the tumor by tearing it out, fragments of the underlying bone are removed along with it. The surface of the tumor is covered with smooth papillary formations of pale pink or reddish light, depending on the degree of vascularization of the tumor. The density of the tumor is determined by its fibrous nature. The tumor has a pronounced extensive growth, dislocating and destroying all tissues and filling all adjacent cavities located on its way (choanae, nasal cavity, orbit, sphenoid sinus, lower parts of the nasopharynx, paranasal sinuses, zygomatic and temporal fossa, etc.). When spreading forward, the tumor fills the nasal passages, destroying the vomer, nasal septum, superior and middle nasal conchae, penetrating into the cells of the ethmoid labyrinth, frontal and maxillary sinuses, deforming the pyramid of the nose and disrupting the beauty of the face. When spreading backward and downward, the tumor destroys the anterior wall of the sphenoid sinus and penetrates it, sometimes reaching the pituitary gland, spreads downward, often reaching the soft palate and oropharynx.

Thus, due to its extensive growth and destructive effect on surrounding organs and tissues, nasopharyngeal fibroma can be classified as "malignant" in clinical terms, but it does not metastasize and histologically is classified as a benign tumor. Morphologically, it consists of vascular plexuses of varying severity and connective tissue stroma consisting of collagen fibers and fibroblasts. The tumor is covered with epithelium, which in the nasopharynx is of the nature of a single-layer squamous epithelium, and in the nasal cavity - a cylindrical ciliated epithelium - a fact that is explained by the fact that the tumor occurs in the transition zone of squamous epithelium to cylindrical. The vascular filling of the tumor, especially venous plexuses, is very large. Veins merge with each other by resorption of their walls, forming whole "lakes" of blood with very fragile "banks", traumatization of which (for example, when sneezing) or spontaneously cause profuse, difficult to stop nasal and pharyngeal bleeding. With the reverse development of the tumor, necrobiosis and hyalinization phenomena occur in the vascular endothelium, and inflammatory phenomena occur in the stroma. As a result, non-viable tumor tissues undergo resorption, the tumor shrinks sharply and is replaced by scar tissue.

Symptoms of nasopharyngeal fibroma

Symptoms of nasopharyngeal fibroma develop slowly and are divided into subjective and objective. In the initial stages of tumor development, gradually increasing difficulty in nasal breathing occurs, sometimes causeless headaches and "dull" pains in the area of the base of the nose, high mental and physical fatigue, due to which children begin to lag behind in mastering the school curriculum, in physical development, and often suffer from colds. Nasal discharge is mucopurulent in nature. Complaints appear first about minor, then about increasingly severe nosebleeds, due to which the child develops anemia. Later, the tumor fills the nasal cavity, causing increasing difficulty in nasal breathing, up to its complete absence. The child's mouth is constantly open, his speech becomes nasal (rhinolalia operta), obstruction of the auditory tube causes hearing loss, at the same time there is a loss of smell and a decrease in taste sensitivity. When the tumor contacts the soft palate, patients complain of impaired swallowing function and frequent choking. Compression of sensitive nerve trunks causes neuralgic eye and facial pain.

During an objective examination, the doctor sees a pale child or young man with a constantly open mouth, blue circles under the eyes and a swollen base of the nose. In the nasal passages there are mucopurulent discharges, which the patient cannot remove by blowing his nose due to obstruction of the choanae by the tumor (expiratory valve). After removing these discharges, the patient sees a thickened hyperemic mucous membrane, enlarged bluish-red nasal turbinates. After lubricating the mucous membrane of the nose with adrenaline and contracting the nasal turbinates, the tumor itself becomes visible in the nasal passages as a slightly mobile smooth, grayish-pink or reddish formation, bleeding heavily when touched with a sharp instrument.

Often, a tumor filling the nasal canopy is combined with one or more common secondary nasal polyps.

Posterior rhinoscopy does not reveal the typical picture, in which the choanae, vomer, and even the posterior ends of the nasal conchae are clearly visible. Instead, a massive, bluish-red tumor is detected in the nasopharynx, completely filling it and sharply different in appearance from banal adenoid vegetations. Digital examination of the nasopharynx, which should be done carefully so as not to cause bleeding, reveals a dense, immobile, solitary tumor.

Concomitant objective symptoms may include lacrimation, exophthalmos, and nasal root widening. When these signs are bilateral, the patient's face takes on a peculiar appearance, which has been called "frog face" in foreign literature. Oropharyngoscopy may reveal a bulging soft palate due to a tumor in the middle parts of the pharynx.

An unremoved tumor grows to enormous sizes, filling the entire space of the nasal cavity, the orbit and, going beyond them, causing severe functional and cosmetic disorders. The most formidable complication is the tumor perforating the cribriform plate and penetrating into the anterior cranial fossa. The initial signs of this complication are manifested by the syndrome of increased intracranial pressure (drowsiness, nausea, vomiting, incurable headache), then signs of retrobulbar syndrome (loss of visual fields, ophthalmoplegia, amaurosis) join. Frequent hemorrhages and unbearable headaches, vomiting and food intolerance lead the patient to a severe general condition, cachexia, anemia, which are not much different from the condition in the presence of a malignant tumor. Often, such advanced conditions, encountered in former times in less civilized areas and countries, were complicated by meningitis and meningoencephalitis, inevitably leading to the death of patients.

Fibromyxoma, or choanal polyp

Fibromyxoma, or choanal polyp, originates in the choanal or ethmoidosphenoid region. Externally, this benign tumor looks like a polyp on a stalk, which is easily removed without bleeding using a special hook. Compared to mucous polyps of the nasal cavity, the consistency of the choanal polyp is denser. It grows in the direction of the pharynx and nasal cavity. "Old" polyps become denser, acquire a reddish color and often simulate nasopharyngeal fibroma, but, unlike it, do not bleed and do not have extensive growth.

Treatment is surgical.

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Sinus-choanal polyp

The sinus-choanal polyp is actually a manifestation of polypous sinusitis, since it originates from the maxillary sinus and prolapses through the choana into the nasopharynx. Less often, this "tumor" originates from the sphenoid sinus. Externally, the sinus-choanal polyp can be compared to the tongue of a bell, which hangs down into the nasopharynx and sometimes reaches the oropharynx, located between its posterior wall and the soft palate. In structure, this polyp is a pseudocystic formation of whitish-gray color of ovoid shape, which completely fills the nasopharynx and causes difficulties in nasal breathing in tubular hearing impairment.

Treatment is surgical.

Nasopharyngeal cysts

Nasopharyngeal cysts occur either as a result of blockage of the mucous gland duct (retention cyst) or Thornwald's pharyngeal sac. Nasopharyngeal cysts are rare tumors characterized by a long evolution and manifested by disturbances of nasal breathing and hearing due to blockage of the nasopharyngeal opening of the auditory tube. Posterior rhinoscopy reveals a smooth, round, gray tumor of elastic consistency. The cyst is removed using an adenotome.

Dermoid cysts of the nasopharynx

Dermoid cysts of the nasopharynx are very rare congenital benign tumors, most often observed in infants. They develop very slowly and produce minimal dysfunction, mainly a dry reflex cough and some discomfort when swallowing. As a rule, the stalk of this "polyp" comes from the lateral wall of the nasopharynx around the nasopharyngeal opening of the auditory tube and often reaches the pharyngeal-epiglottic fold. It is not detected during normal pharyngoscopy, but with a gag reflex it can appear in the oropharynx as an elongated solitary polyp of a whitish-gray color with a smooth surface. Its surface has a leathery appearance with papillae, sweat and sebaceous glands, and hairs. Under this layer is tissue penetrated by venous vessels. In the center of the tumor, a core is determined, formed by dense connective tissue, sometimes containing fragments of bone or cartilage tissue, as well as striated muscle fibers (a typical "set" of tissues for embryonic tumors). Treatment consists of cutting the cyst stalk. Subsequently, dermoid cysts of the nasopharynx become sclerotic and after some time (months - several years) are absorbed.

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Papillomas and lipomas of the pharynx

Papillomas and lipomas are benign tumors that are rarely found in the upper parts of the pharynx and are visually very difficult to distinguish from banal adenoid tissue. The final diagnosis is established by histological examination. They are removed using an adenotome.

Meningocele of the skull base can sometimes occur in the nasopharynx and most often in children. It differs from other benign tumors in that it increases when the child cries. Such "tumors" are not subject to treatment, since they are accompanied by other severe anomalies in the development of the skull and other organs, usually incompatible with life.

Benign plasmacytoma

Benign plasmacytoma originates from the reticuloendothelial tissue and occurs most often in the bone marrow; more than 80% of extramedullary tumors of this type are localized in the upper respiratory tract. In appearance, they resemble polypoid formations of a grayish or pinkish-violet color, do not ulcerate. The diagnosis is based on histological examination. Solitary plasmoditoma can be both benign and malignant. Benign plasmacytoma is rare, it should not be confused with a simple granuloma consisting of a large number of plasma cells. Malignant plasmacytoma is excluded by the fact that radiography does not reveal bone lesions, sternal puncture does not reveal pathological changes in the bone marrow, myeloma cells are absent, Bence Jones protein is not detected in the urine and, finally, relapse is not observed after tumor removal. Protein fractions of the blood are also examined, which remain at a normal level in benign tumors. Most plasmacytomas are malignant tumors of either extramedullary localization or have the character of "diffuse" myeloma, which is the essence of myeloma disease.

Benign plasmacytomas, if they cause certain functional disorders, depending on their size, are removed by various surgical methods, after which they do not relapse. Malignant plasmacytomas are not subject to surgical treatment. Non-surgical antitumor methods are used for them.

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Diagnosis of nasopharyngeal fibroma

The diagnosis of nasopharyngeal fibroma is established mainly by the clinical picture, the fact of occurrence of nasopharyngeal fibroma in males in childhood and adolescence. The prevalence of the tumor is established using X-ray or MRI or CT examination, as well as using angiography.

Differential diagnostics of nasopharyngeal fibroma is of great importance, since its results determine the treatment tactics and, possibly, the prognosis. Nasopharyngeal fibroma is differentiated from adenoids, cysts, fibromyxoma, cancer and sarcoma of the nasopharynx. The main distinguishing feature of fibromas is their early and frequent bleeding, which is not observed at all in all other benign tumors of this localization, and in malignant tumors, bleeding is observed only at their advanced clinical and morphological stage.

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Treatment of nasopharyngeal fibroma

Numerous attempts to use non-surgical treatment methods (physiotherapy, sclerosing, hormonal) did not provide a radical cure; the only method that often resulted in complete recovery, especially in combination with non-surgical methods, was surgical. However, the classical method of tumor extraction by tearing it from the attachment site using special forceps via oral access, which was used in the past, was not justified due to the impossibility of removing the fibrous base of the tumor, firmly fused with the periosteum (hence the inevitable relapses) and severe, difficult to stop intraoperative bleeding. To facilitate access to the tumor, the French rhinoplasty surgeon Nelaton proposed splitting the soft and hard palate. Other approaches to the tumor were also developed, for example, the use of a rhinotomy method using a para-lateronasal Moore incision or a sublabial Denker rhinotomy.

Denker's operation is a preliminary surgical intervention for the creation of wide access to internal pathological formations of the nasal cavity and, in particular, to the maxillary sinus, middle and posterior parts of the nasal cavity and the base of the skull (nasopharynx, sphenoid sinus). In advanced cases, when the tumor grows into the zygomatic region, in the paranasal sinuses, orbit or retromaxillary region, it is removed after creating preliminary approaches. According to A.G. Likhachev (1939), the most advantageous approach to the tumor is the transmaxillary Denker's. But in some cases, depending on the histological features and prevalence of the tumor, the use of radiation therapy leads to a delay in tumor growth, its reduction and compaction, which helps to reduce intraoperative bleeding and facilitates its surgical removal. The same effect is achieved by infiltration of the tumor with 96% ethyl alcohol. In some cases, surgery is performed several times before the end of puberty, when relapses cease, the tumor stops developing and begins to reverse.

Surgical intervention requires thorough preoperative preparation (improvement of the general condition of the body, normalization of blood indices, vitaminization, prescription of calcium preparations to strengthen the vascular wall, measures to increase hemostatic indices). Preparation for surgery should provide for the possibility of carrying out resuscitation measures, blood transfusion and blood substitutes during it. Surgical intervention is carried out under intratracheal anesthesia. In the postoperative period, the same measures are carried out as during the period of preoperative preparation of the patient.

Non-surgical treatment methods as independent means do not always give positive results; it is advisable to carry them out as a preoperative preparation or as an attempt at non-surgical treatment.

For small tumors, diathermocoagulation can be used with an endonasal approach in people aged 18-20 years, with the expectation that they will soon complete puberty and no more relapses will occur. At the same age, diathermy can be used for small postoperative relapses.

Radiation therapy is indicated mainly as a protective treatment, since fibromatous tissue is not sensitive to X-rays, but it does stabilize the growth of young cells, new vascular plexuses, which are obliterated, thereby limiting the access of nutrients to the tumor and slowing its growth. The course of treatment usually lasts 3-4 weeks with a total dose of 1,500 to 3,000 rubles.

Treatment with radioactive elements introduced into the tumor is currently practically not used due to possible secondary complications (atrophy of the mucous membrane of the nose and nasopharynx, necrotizing ethmoiditis, perforation of the palate, etc.). Currently, radium and cobalt have been replaced by radon, which is placed in gold capsules. The latter are implanted into the tumor at a distance of 1 cm from each other in the amount of 5-6. The procedure can be repeated after a month; this method does not cause such serious complications as with the application of radium or cobalt.

The main hormonal agent in the treatment of nasopharyngeal fibromas is testosterone, which has an androgenic, antitumor and anabolic effect. It regulates the development of male genitals and secondary sexual characteristics, accelerates puberty in males, and also performs a number of other important biological functions in the developing organism. It is used in various dosage forms (capsules, tablets, intramuscular and subcutaneous implants, oil solutions of individual esters or their combinations). For nasopharyngeal fibromas, 25 to 50 mg/week of the drug is used for 5-6 weeks. Treatment is carried out under control of the content of 17-ketosteroids in urine - normally, the excretion of 17-ketosteroids in men averages (12.83±0.8) mg/day (from 6.6 to 23.4 mg/day), in women - (10.61±0.66) mg/day (6.4-18.02 mg/day) and can be repeated with normal content of this excreta in urine. Testosterone overdose can lead to testicular atrophy, early appearance of secondary sexual characteristics in children, osteognosis and mental disorders, as well as to an increase in the content of 17-ketosteroids in urine.

What is the prognosis for nasopharyngeal fibroma?

The prognosis depends on the tumor prevalence, timeliness and quality of treatment. In small tumors, recognized at the very beginning of their occurrence, and appropriate radical treatment, the prognosis is usually favorable. In advanced cases, when it is impossible to perform radical treatment, and frequent palliative surgical and other interventions, as a rule, end in relapses and, possibly, tumor malignancy - the prognosis is pessimistic. According to the most extensive foreign statistics, the mortality rate in the second half of the 20th century in surgical interventions for nasopharyngeal fibromas was 2%.