2012, Volume 28, Number 3, Page(s) 274-277
Polymorphous Low-Grade Adenocarcinoma Located in the Maxillary Sinus
Demet ETİT1, Deniz ALTINEL1, Ümit BAYOL1, Ayça TAN1, Özlem TÜRELİK1, İbrahim ÇUKUROVA2
1Department of Pathology, İzmir Tepecik Education and Research Hospital, İZMİR, TURKEY
2Department of Otorhinolaryngology, İzmir Tepecik Education and Research Hospital, İZMİR, TURKEY
Keywords: Adenocarcinoma, Maxillary sinus, Paranasal sinuses
Polymorphous low-grade adenocarcinoma is a malignant epithelial
tumour with low metastatic rate and infiltrative growth pattern. The
palate is the most common site. Paranasal sinuses are uncommon
venues for polymorphous low-grade adenocarcinoma. Here, we
report a polymorphous low-grade adenocarcinoma case of the
maxillary sinus, a very rare location. Although it is a low grade
malignancy, progression may develop after a long time. Therefore,
polymorphous low-grade adenocarcinoma should be kept in mind
in the differential diagnosis even in rare sites in the head and neck.
Polymorphous low-grade adenocarcinoma (PLGA) is a
malignant neoplasm characterized by cytologic uniformity,
low aggressive rate and infiltrative growth pattern1
PLGA is the second most common intraoral malignant
salivary gland tumor accounting for 26% of all carcinomas
in this location2
. The palate is the most common site,
while the buccal mucosa, retromolar region, upper lip and
the base of the tongue are frequent locations3,4
salivary and lacrimal glands, nasopharynx, nasal cavity and
paranasal sinuses are uncommon sites for PLGA5-17
report a case of a recurrent PLGA located in the maxillary
A 35-year-old male presented first with a painless mass in
the right maxillary sinus in 1988 which had destructed the
bone of the nasal septum, and was diagnosed as a mixed
tumor with local invasion. Following two recurrences
in 2006 and 2008, the mass re-appeared in July 2009.
Computerized tomography showed that a soft tissue
mass completely filled the right maxillary sinus. Because
of the significant destruction at the lateral orbital wall, orbital floor and bony structures, the unilateral eye was
proptotic in appearance (Figure 1
). A hemimaxillectomy
and right orbital exenteration was performed in the
Otorhinolaryngology Clinic of our hospital, because of the
widely invasive surrounding tissue mass.
Click Here to Zoom
|Figure 1: The maxillofacial computerized tomography (axial
plan) shows a 7 cm mass arising in the right maxillary sinus
eroding surrounding soft tissue and bones as as well as the orbital
On gross examination, the lesion was 6,5x5x4 cm in size,
appearing as a white, solid mass with a whirling pattern on
the cut surface, filling the right maxillary sinus completely,
infiltrating into the orbital muscles and adipose tissue as
well as orbital bone and soft tissue. No definitive capsule
was identified. Histological examination showed tumor
cells arranged in various amounts of solid, ductal, tubular
and trabecular patterns. The tumor cells were mostly
isomorphic in appearance, with round to oval or fusiform
nuclei and bland nuclear chromatin and had a moderate
amount of eosinophilic to clear cytoplasm. The cells were
small and lacking nuclear atypia. Mitotic figures were rare
and necrosis absent. Crystalloids resembling the tyrosinerich
crystals were noted in focal areas. The surrounding
muscle, fat and bone tissues were infiltrated by tumor cells.
Perineural invasion was also noted. Immunohistochemical
studies showed Cytokeratin 7 (CK), S100, SMA, p63, EMA
positivity. CK20, GFAP, CK5/6, vimentin, CEA, CD10 were negative. The diagnosis was PLGA with detailed
morphological and immunohistochemical evaluation
(Figures 2–6). Reconstructive surgery was also performed.
The patient did well and was free of disease at the last followup,
twenty months after the last surgical intervention.
Click Here to Zoom
|Figure 2: Various combinations of solid, tubular and trabecular
patterns of the tumor (H&E, x10).
Click Here to Zoom
|Figure 4: Ductal structures demonstrating central eosinophilic
material (H&E, x20).
Click Here to Zoom
|Figure 6: Smooth muscle actin positivity in the myoepithelial
layer of the tumor nests (x20).
PLGAs are malignant epithelial tumors with a low aggressive
rate and infiltrative growth pattern1
. It is one of the
commonest intraoral malignant salivary gland tumor2
Typically, the palate is most commonly involved by PLGA.
The buccal mucosa, retromolar region, upper lip and the
base of the tongue are frequent locations3,4,18. Major
salivary and lacrimal glands, nasopharynx, nasal cavity and
paranasal sinuses are unexpected venues for PLGA5-17.
There are only three reports mentioning a maxillary location
of PLGA in the literature. One of them was intraosseous19, the other simulated a maxillary odontogenic cyst
around an impacted tooth20. The case from Charous et
al. is the single report to our knowledge that resembles the
current case arising from the maxillary sinus6.
PLGAs are dominantly seen in females. The age varies
between 16–94 years with a mean of 59 years3,4.
Although the present case was a 35-year-old male when
the specimen was sent to our pathology laboratory, the first
mass appeared in his maxillary sinus when he was fourteen,
meaning he is the youngest PLGA case in the literature to
Painless swelling is the most common symptom. The
existence of the lesion has been observed from weeks to
40 years3. Our case came with a painless swelling on
the right side of the face 21 years ago, then presented three
more times in the last three years with local recurrences.
PLGA occasionally shows a firm, well-circumscribed, nonencapsulated
mass with an average size of 2.2 cm3 while
the current case was 6.5 cm in greatest dimension as a
PLGA cases appear in a variety of configurations in
trabecular, tubular, solid, papillary and cribriform patterns, which is a significant feature for these carcinomas1. The
current case also showed a tubular appearance.
The neoplastic cells of the PLGAs show immunoreactivity
with antibodies to cytokeratin, vimentin, S–100 protein,
CEA, GFAP, EMA3,21,22. In our case, CK7, S100, SMA,
p63, EMA positivity and CK20, GFAP, CK5/6, vimentin,
CEA, CD10 negativity were observed.
Pleomorphic adenoma (PA) and adenoid cystic carcinoma
(AdCC) are included in the differential diagnosis.
Distinguishing PLGA from PA is often not possible on a
cytomorphologic basis. PA is composed of proliferating
epithelial, stromal and myoepithelial cells which lack
an infiltrative pattern that is characteristic for PLGA1.
Although PA of the minor glands are often unencapsulated,
they do not infiltrate the adjacent tissues such as fat, muscle
or bone. Myxochondroid and chondroid areas are present
more commonly in PA than PLGA1.
Distinguishing PLGA from AdCC is mostly based on
cytologic properties. Cells in PLGA are more round to oval
with bland nuclear chromatin and a moderate amount of
eosinophilic to clear cytoplasm, in contrast to AdCC that
has more basaloid features. Furthermore, large pseudocystic
spaces are more characteristic for AdCC than PLGA. The
solid areas of PLGA also lack the nuclear pleomorphism,
small and angular nuclei, necrosis and mitotic activity that
are often seen in the solid variant of AdCC3,22,23. The
current case was an infiltrative lesion with no significant or
atypical mitosis and necrosis.
Treatment includes complete surgical excision. Maxillectomy
and right orbital exenteration were performed in our
case. Radiotherapy (RT) was performed after both the first
and the second operations and chemotherapy was carried
out after the last operation together with RT.
PLGA has a relatively good prognosis3,4,24. Our patient
did well postoperatively and he was free of disease at the last
follow-up despite the three recurrences in a 21-year period.
In conclusion, the maxillary sinus is a very rare location for
PLGA. As its name implies, this is a low-grade malignancy
and the progression and the treatment can take a long time,
sometimes causing vital tissue loss as in the current case.
PLGA should be kept in mind in the differential diagnosis,
even in rare sites in the head and neck.
We would like to respectfully offer our regards to Prof. Dr.
Feriha Öz for her experience and knowledge on the basis of
the initial pathology report in 1988.
1) Luna MA, Wenig BM: Polymorphous low-grade adenocarcinoma. In Barnes L, Eveson JV, Reichart P, Sidransky D (Eds): Pathology and Genetics of Head and Neck Tumours, Lyon, IARC Press, 2005, 225-226
2) Waldron CA, el-Mofty SK, Gnepp DR: Tumors of the intraoral minor salivary glands: a demographic and histologic study of 426 cases. Oral Surg Oral Med Oral Pathol 1988, 66: 323-33, [ PubMed ]
3) Castle JT, Thompson LD, Frommelt RA, Wenig BM, Kessler HP: Polymorphous low grade adenocarcinoma: a clinicopathologic study of 164 cases. Cancer 1999, 86: 207-219, [ PubMed ]
4) Evans HL, Luna MA: Polymorphous low-grade adenocarcinoma: a study of 40 cases with long-term follow up and an evaluation of the importance of papillary areas. Am J Surg Pathol 2000, 24: 1319-1328, [ PubMed ]
5) Arathi N, Bage AM: Polymorphous low-grade adenocarcinoma of parotid gland: a rare occurrence. Indian J Pathol Microbiol 2009, 52: 103-105, [ PubMed ]
6) Charous DD, Cunnane MF, Rosen MR, Keane WM: Recurrent polymorphous low-grade adenocarcinoma manifesting as a sinonasal mass: a case report. Ear Nose Throat J 2005, 84:356-357, [ PubMed ]
7) Garzaro M, Pecorari G, Landolfo V, Campisi P, Reali A, Giordano C: Nasopharyngeal polymorphous low-grade adenocarcinoma in a patient with nonfunctioning pituitary macroadenoma. B-ENT 2010, 6: 59-62, [ PubMed ]
8) Gonzalez-Lagunas J, Alasa-Caparros C, Vendrell-Escofet G, Huguet-Redecilla P, Raspall-Martin G: Polymorphous low-grade adenocarcinoma of the nasal fossa. Med Oral Patol Oral Cir Bucal 2005, 10: 367-370, [ PubMed ]
9) Lengyel E, Somogyi A, Godeny M, Szerdahelyi A, Nemeth G: Polymorphous low-grade adenocarcinoma of the nasopharynx. Case report and review of the literature. Strahlenther Onkol 2000, 176: 40-42, [ PubMed ]
10) Lloreta J, Serrano S, Corominas JM, Ferres-Padro E: Polymorphous low-grade adenocarcinoma arising in the nasal cavities with an associated undifferentiated carcinoma. Ultrastruct Pathol 1995, 19: 365-370, [ PubMed ]
11) Merchant WJ, Cook MG, Eveson JW: Polymorphous low-grade adenocarcinoma of parotid gland. Br J Oral Maxillofac Surg 1996, 34: 328-330, [ PubMed ]
12) Nagao T, Gaffey TA, Kay PA, Minato H, Serizawa H, Lewis JE: Polymorphous low-grade adenocarcinoma of the major salivary glands: report of three cases in an unusual location. Histopathology 2004, 44: 164-171, [ PubMed ]
13) Pintor MF, Figueroa L, Martinez B: Polymorphous low grade adenocarcinoma: review and case report. Med Oral Patol Oral Cir Bucal 2007, 12: E549-551, [ PubMed ]
14) Ritland F, Lubensky I, LiVolsi VA: Polymorphous low-grade adenocarcinoma of the parotid salivary gland. Arch Pathol Lab Med 1993, 117: 1261-1263, [ PubMed ]
15) Ruiz-Godoy L, Suarez L, Mosqueda A, Meneses A: Polymorphous low-grade adenocarcinoma of the parotid gland. Case report and review of the literature. Med Oral Patol Oral Cir Bucal 2007, 12: E30-33, [ PubMed ]
16) Tamiolakis D, Thomaidis V, Tsamis I, Kariki E, Kotini A, Lambropoulou M, Boglou P, and Papadopoulos N: Polymorphous low grade adenocarcinoma of the parotid gland. Cytological, histological and immunohistochemical features and review of the literature. Acta Medica (Hradec Kralove) 2004, 47: 3-6, [ PubMed ]
17) Wei YC, Huang CC, Chien CY, Hwang JC, and Chen WJ: Polymorphous low-grade adenocarcinoma of the nasopharynx: a case report and brief review. J Clin Pathol 2008, 61: 1124-1126, [ PubMed ]
18) Scally CM, Irwin ST, and Nirodi N: Low grade polymorphous adenocarcinoma of a minor salivary gland. J Laryngol Otol 1988, 102: 284-287, [ PubMed ]
19) Sato T, Indo H, Takasaki T, Kawabata Y, Morita Y, and Noikura T: A rare case of intraosseous polymorphous low-grade adenocarcinoma (PLGA) of the maxilla. Dentomaxillofac Radiol 2001, 30: 184-187, [ PubMed ]
20) Geha H, Boland FX, Francois A, Tardif A, and Peron JM: Polymorphous low-grade adenocarcinoma of the maxilla simulating an odontogenic cyst. Rev Stomatol Chir Maxillofac 2010, 111: 105-107, [ PubMed ]
21) Wenig BM, Harpaz N, and DelBridge C: Polymorphous low-grade adenocarcinoma of seromucous glands of the nasopharynx. A report of a case and a discussion of the morphologic and immunohistochemical features. Am J Clin Pathol 1989, 92: 104-109, [ PubMed ]
22) Perez-Ordonez B, Linkov I, and Huvos AG: Polymorphous low-grade adenocarcinoma of minor salivary glands: a study of 17 cases with emphasis on cell differentiation. Histopathology 1998, 32: 521-529, [ PubMed ]
23) Brown AM, Castle J, Hebbachi AM, and Gibbons GF: Administration of n-3 fatty acids in the diets of rats or directly to hepatocyte cultures results in different effects on hepatocellular ApoB metabolism and secretion. Arterioscler Thromb Vasc Biol 1999, 19: 106-114, [ PubMed ]
24) Evans HL and Batsakis JG: Polymorphous low-grade adenocarcinoma of minor salivary glands. A study of 14 cases of a distinctive neoplasm. Cancer 1984, 53: 935-942, [ PubMed ]