Учебники / Textbook and Color Atlas of Salivary Gland Pathology - DIAGNOSIS AND MANAGEMENT Carlson 2008

96 Cysts of the Salivary Glands

dure is marsupialization with packing (Baurmash 1992). The author contends that routine sublingual removal is inappropriate therapy for several reasons. The first is that the term “ranula” is loosely applied to any cyst-like structure of the floor of the mouth. He believes that some of these lesions are unrelated to the sublingual gland, such that its removal is not indicated. Specifically, he cites the existence of mucoceles arising from the mucous-secreting incisal gland in the anterior floor of the mouth, single or multiple retention cysts involving the openings of the ducts of Rivinus, and retention cysts at Wharton’s duct orifice that can resemble the sublingual gland associated ranula but that would possibly not be cured with sublingual gland removal. Moreover, the author states that sublingual gland excision is potentially associated with significant morbidity such as injury to Wharton’s duct with resultant salivary obstruction or salivary leakage, and lingual nerve injury (Baurmash 1992). Zhao and his group presented an objective assessment of complications associated with surgical management of ranulas treated with a variety of procedures (Zhao, Jia, and Jia 2005). These included 9 marsupializations, 28 excisions of the ranula only, 356 sublingual gland excisions, and 213 excisions of both the sublingual gland and ranula. A total of 569 sublingual gland excisions were performed in 571 patients undergoing 606 operations. Injury to Wharton’s duct occurred in 11 of 569 patients who underwent excision of the sublingual gland with or without excision of the ranula, compared to 0 of 37 patients who did not undergo sublingual gland excision. Injury to the lingual nerve occurred in 21 of the patients who underwent sublingual gland excision, compared to 0 patients who did not undergo sublingual gland excision. Of particular note is that recurrence of the ranula occurred in 1.2% of patients who underwent excision of their sublingual glands, compared to 60% of patients who underwent marsupialization or excision of the ranula only. Baurmash laments that simple marsupialization has fallen into disfavor because of the excessive number of failures associated with this procedure (Baurmash 1992). The recurrence patterns have been confirmed by other authors, as well (Yoshimura et al. 1995). As such, he recommends packing the cystic cavity with gauze for 7–10 days. In so doing, he reports that the recurrence rate is reduced to 10–12% (Baurmash 2007). McGurk points out that the downside of this procedure is that the results are unpredictable and that the packing is uncomfortable for the patient

(McGurk 2007). He concludes by stating that reliable eradication of the ranula comes from removal of the sublingual gland. It is true that the surgery is somewhat anatomically demanding, such that some surgeons may wish to defer the sublingual gland excision for recurrences. Unfortunately, the development of scar tissue in the floor of the mouth is such that the anatomy may be more obscured related to a recurrence after a marsupialization and packing procedure. With this issue in mind, a sublingual gland excision should probably be performed from the outset (Figure 4.8). While the

Figure 4.8a. The excision of the sublingual gland and associated ranula from Figure 4.1. An incision is designed over the prominence of the sublingual gland and ranula, and lateral to Wharton’s duct.

Figure 4.8b. Careful dissection allows for separation of the mucosa from the underlying pseudocystic membrane.

Figure 4.8c. The dissection continues to separate the sublingual gland from surrounding tissues, including the underlying Wharton’s duct and the lingual nerve beneath Wharton’s duct.

Figure 4.8d. The specimen and ranula are able to be delivered en bloc.

Figure 4.8g. The remaining tissue bed shows the anatomic relationship of the preserved superficial Wharton’s duct and underlying lingual nerve. Wharton’s duct originates posteriorly in a medial position to the lingual nerve and terminates in a position lateral to the nerve. The sublingual vein can be visualized in the tissue bed lateral to the anterior aspect of Wharton’s duct.

Figure 4.8h. Healing is uneventful as noted in the 1-month postoperative image.

e	f
	Figures 4.8e and 4.8f. If the pseudocyst bursts intraoperatively, no compromise in cure exists as long as the sublingual
	gland is completely excised. The histopathology shows the non-epithelial lining (e) and the intimate association of the sub-
	lingual gland and mucous escape reaction (f).

Figure 4.9. The specimen from the excision of the mucocele seen in Figure 4.3. The minor salivary gland tissue remains attached to the mucous escape reaction.

b

c

Figure 4.10a. The patient seen in Figure 4.7 underwent excision of her left sublingual gland for her plunging ranula. The specimen includes the sublingual gland and associated mucous escape reaction.

Figures 4.10b and 4.10c. Her 2-year postoperative examination shows no mass in the submandibular region (b) and a normal oral examination without recurrence of the ranula (c).

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anatomy of the floor of the mouth might be considered foreign and intimidating to some surgeons, preservation of the lingual nerve and Wharton’s duct is not a difficult task, and treatment of this pathologic process with sublingual excision should be a curative procedure. One pathologic and clinical similarity of the ranula and mucocele is their derivation from salivary gland tissue. There does not seem to be a dispute among clinicians as to the best surgical therapy for the mucocele, with complete surgical excision of the etiologic minor salivary tissue along with the mucous escape reaction being highly accepted (Figure 4.9). As such, it is advisable to apply the same approach to the ranula that only differs from the mucocele in the anatomic region in which it occurs. With regard to the ranula and plunging ranula, even the most extensive lesions are predictably treated for cure with excision of the offending sublingual gland. While it is not essential to remove the non-epithelial lined pseudocyst with the sublingual gland, it is common for the tightly adherent pseudocyst to be delivered with the sublingual gland specimen (Figure 4.10). As such, documentation of a plunging component to the ranula serves a matter of medical completeness rather than implications for treatment.

Cyst of Blandin and Nuhn’s Gland

On rare occasions, the mucosa of the ventral surface of the tongue may become a source for the

Figure 4.11. A cyst of Blandin and Nuhn’s gland of the ventral surface of the tongue. Simple excision of the cyst and associated minor salivary gland tissue is curative for this mucous escape phenomenon.

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development of a mucous escape reaction. This process is referred to as a cyst of Blandin and Nuhn’s gland (Figure 4.11). This designation is a misnomer, as this process represents a mucous escape reaction, rather than a true cyst. In this sense, then, it represents a ranula of the tongue. Simple excision of the “cyst” and the associated gland of Blandin and Nuhn is the treatment of choice with recurrence being uncommon.

Mucous Retention Cyst

The mucous retention cyst is less common than the mucous escape reaction. This entity is a true cyst that is lined by epithelium. The exact classification of this lesion seems to be in question. Some prefer to simply include it with the more common mucous escape reaction, whereas others describe it as a separate entity (Koudelka 1991). The pathogenesis seems to be related to partial obstruction of a duct, as opposed to complete severance of the salivary duct that is seen in the mucous escape reaction. The increased pressure in the salivary duct causes dilatation without rupture such that proliferation of the ductal epithelium occurs. The Armed Forces Institute of Pathology reviewed 178 cases of mucous retention cysts, accounting for 0.9% of all salivary gland pathology cases in their files (Koudelka 1991). One hundred seventy-one cases (96%) occurred in the major salivary glands, with 156 (87.6%) occurring in the parotid gland (Figure 4.12), 14 cases (7.8%) occurring in the submandibular gland, and only 1 case occurring in the sublingual gland. Only 1 case was specifically documented as occurring in the minor salivary glands. The mean age of patients was late 40s, with a nearly equal gender predilection. The clinical presentation of the mucous retention cyst is that of a slowly enlarging, painless, fluctuant soft tissue swelling that may persist from months to years. These cysts vary in their size, and the color of the overlying tissues depends on their depth within the soft tissue. Superficial lesions are blue in color, whereas deep lesions take on the same color of the overlying tissue. Some pathologists have split the mucous retention cysts into separate categories. Eversole has categorized these lesions as mucous retention cysts, reactive oncocytoid cysts, and mucopapillary cysts (Eversole 1987.) In his series of 121 mucous retention cysts, he found 70 mucous retention cysts, 41 reactive oncocytoid

100 Cysts of the Salivary Glands

a b

Figures 4.12a and b. A mucous retention cyst of the parotid gland as noted on MRI (T1 images, a; T2 images, b). The patient underwent a superficial parotidectomy due to the concern for a cystic neoplasm.

c

d

Figures 4.12c and 4.12d. Histopathology showed a parotid cyst lined by columnar epithelium in one section of the cyst

(c) and squamoid epithelium in another section (d).

cysts, and 10 mucopapillary cysts. From a pathologic and surgical standpoint, perhaps the most striking piece of information in this report was the need to distinguish the mucopapillary cyst from the low-grade mucoepidermoid carcinoma.

Treatment of mucous retention cysts is most commonly conservative surgical excision (Figure 4.12). Cysts within or closely associated with a salivary gland should include that salivary gland with the excision. Some mucous retention cysts, however, may be removed without the inclusion of the salivary gland, a distinct departure from the recommendations associated with mucous escape reactions.

Parotid Cysts Associated with Human Immunodeficiency Virus Infection

Infection with the human immunodeficiency virus has been shown to manifest in a variety of ways. Symptoms related to the head and neck have historically been encountered in this disease. It has been reported that 41% of patients with acquired immunodeficiency syndrome (AIDS) initially presented with signs or symptoms of head and neck disease (Marcussen and Sooy 1985). Salivary gland diseases include the enlargement of major salivary

glands with or without hypofunction and xerostomia (Owotade, Fatusi, and Adebiyi et al. 2005). In early lesions the submandibular and sublingual glands are often initially affected and enlarged. As the disease progresses, however, parotid gland swelling is more commonly noted. As many as 5– 10% of patients with HIV-1 infection have been reported to have parotid swelling with the incidence increasing to approximately 20% in AIDS patients (Owotade, Fatusi, and Adebiyi et al. 2005). Ryan and his group were the first to describe salivary gland involvement in HIV disease as intrasalivary gland lymphadenopathy (Ryan, Ioachim, and Marmer et al. 1985). Shortly thereafter, parotid gland cysts were reported and were noted to resemble the benign lymphoepithelial lesion (BLL) histologically (Colebunders, Francis, and Mann et al. 1988). The BLL is a benign sialadenopathy associated with Sjogren’s syndrome with pathognomonic

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epimyoepithelial islands. It is felt to represent an autoimmune reaction in Sjogren’s syndrome, but the BLL is felt to be of unknown pathogenesis in HIV (Sperling, Lin, and Lucente 1990). It remains unclear whether lymphoepithelial cysts within parotid glands in HIV/AIDS patients develop from pre-existing salivary gland inclusions in intraparotid lymph nodes or from a lymphoepithelial lesion of the parenchyma of the salivary gland.

Treatment of lymphoepithelial cysts of the parotid gland in HIV/AIDS patients is a function of the size of the cysts, the patient’s concern for cosmetics, and compliance with medical therapy. Following their original description, these cysts were managed in a variety of ways including periodic aspirations, simple excision of the cysts, and nervesparing superficial parotidectomy (Figure 4.13). Shaha and his group reported an early experience with 50 patients with lymphoepithelial cysts of the

a

b

Figures 4.13a and 4.13b. A 50-year-old HIV positive male presented in 1994 with obvious right parotid swelling. This time period pre-dated the development of HAART. Examination of the bilateral parotid gland regions revealed a large mass of the right parotid gland, and a smaller mass of the left parotid gland.

Figure 4.13c. Computerized tomograms confirmed the fi ndings of the physical examination. A clinical diagnosis of bilateral lymphoepithelial cysts was made. The patient requested removal of these cysts.

Figure 4.13d. A standard incision was made.

e	f
	Figures 4.13e and 4.13f. This permitted unroofing of the large cyst in the right parotid gland (e) and the smaller cysts in
	the left parotid gland (f).

g	h
	Figures 4.13g and 4.13h. The specimen from the right parotid gland (g) and the left parotid gland (h) showed typical gross
	signs of lymphoepithelial cysts.

Figure 4.13i. The resultant right parotid tissue bed is noted.

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j

l

k

m

		Cysts of the Salivary Glands 105
a		b

Figures 4.14a and 4.14b. A 35-year-old HIV positive man presented in 2005 with a complaint of bilateral parotid swellings. He admitted to non-compliance with his HAART. His CD4/CD8 was 0.69 at the time of initial consultation. Physical examination revealed an obvious right parotid swelling and a subtle mass of the left parotid gland.

bilateral parotid glands (Shaha, DiMaio, and Webber et al. 1993). Their initial approach involved superficial parotidectomy with identification and preservation of the facial nerve. They subsequently performed excision of the cyst only. Ferraro and his group recommended against superficial parotidectomy due to possible recurrence in the deep lobe at a later date (Ferraro et al. 1993). They indicated that aspiration is usually ineffective as a long-term solution because of the high rates of recurrence, in addition to the inability to obtain a tissue diagnosis of the cyst wall. Their solution for recurrence of the cyst was a second enucleation procedure.

Improved and evolving pharmacologic therapy of HIV/AIDS has changed the manage-

ment of these cysts. Highly active antiretroviral therapy (HAART) uses combinations of drugs to maximize viral suppression and minimize selection of drug-resistant strains. Most commonly, HAART consists of a backbone of two nucleoside analog reverse transcriptase inhibitors in combination with either a protease inhibitor or a nonnucleoside reverse transcriptase inhibitor. Gland enlargement has been shown to be significantly and positively associated with viral load in a linear fashion (Mulligan, Navazesh, and Komaroff et al. 2000). Compliance with HAART, therefore, has led to the observation that this therapy will result in these cysts subsiding without the need for surgery (Figure 4.14).

Figures 4.13j, 4.13k, 4.13l, and 4.13m. Six months postoperatively, the patient showed well-healed surgical sites without signs of recurrent lymphoepithelial cysts.