Ptcciii

36%

Mucinous type

Alveolar goblet Signet-ring

48% 0%

Mixed

Transitional

71%

aPTCC, papillary tubular cylinder cell

'Survival data derived from Kleinsasser and Schroeder {1333}

reactivity (43% to 93% of cases) {800}. CDX-2, a nuclear transcription factor involved in the differentiation of intestinal epithelial cells and diffusely expressed in intestinal adenocarcinomas, is commonly expressed in ITACs {800}. Information on CEA staining in ITACs is conflicting {1687,2660}. Scattered or groups of chromogranin-positive cells are frequently identified {1687}; these neuroendocrine cells may express a variety of hormone peptides, including serotonin, cholecystokinin, gastrin, somatostatin and leu-enkephalin {163}.

Electron microscopy

ITAC demonstrates features of the intestinal epithelium {163}. Columnar cells present regular microvilli with cores of microfilaments that combine to form a band that inserts into the zonula adherens of the junctional complexes. Glycocalyceal bodies as characteristic of intestinal-type epithelium may be identified between the microvilli. Endocrine cells with neurosecretory granules, Paneth cells with large exocrine granules, and goblet cells containing several mucin droplets in the apical cytoplasm are present in variable numbers.

Precursor lesions

The frequent presence of squamous metaplasia and/or dysplasia of the sinonasal epithelium in the vicinity of the tumour impairs mucociliary clearance, resulting in prolonged contact of carcinogenic substances with the mucosa {2789}.

Histogenesis

It has been hypothesized that ITAC derives from a stem cell capable of undergoing differentiation into various type of epithelial cells (resorptive cells, goblet cells, neuroendocrine cells, Paneth cells) {1739}.

Genetics

Genetic data are limited {2012,2013, 2218,2829}. K-RAS or H-RAS mutation has been detected in only about 15% of cases {2012,2218}. TP53 mutations are reported in 18-44% of cases {2013,2829}; mutations consist more frequently of C:G to A:T transitions and involve the CpG dinucleotides. Other gene alterations include loss of heterozygosity (LOH) at 17p13 and 9q21, and promoter methylation of p14(ARF) and p16(INK4a). A close association between TP53, p14(ARF) and p16(INK4a) gene deregulation has been found in tumours from individuals occu-pationally exposed to dusts {2013}.

Prognosis and predictive factors

Sinonasal ITACs are generally locally aggressive tumours with frequent local failure (about 50% of cases), whereas metastasis to cervical lymph nodes and spread to distant sites are infrequent (about 10% and 20%, respectively) {124,799,804,1333}. The 5-year cumulative survival rate is around 40%, with most deaths occurring within 3 years. Since most patients present with advanced local disease, clinical staging generally has no relevant prognostic significance.

The histologic subtype has been identified as indicative of clinical behaviour in different series {124,799,804,1333}. The papillary type (papillary tubular cylinder cell adenocarcinoma I = well-differentiated adenocarcinoma) has a more indolent course, with little tendency to distant spread (5-year survival rate of about 80%). Conversely, the solid type (papillary tubular cylinder cell adenocarcino-ma III = poorly differentiated adenocarcinoma) and mucinous type adenocarcinoma have a very poor survival. Other factors that have been associated with a more aggressive behaviour are: H-RAS mutation, chromogranin expression and c-erbB-2 expression {855,1687,2012}. Although it has been suggested that ITACs occurring in occupational exposed individuals have a better prognosis than sporadic ITACs {124}, this has not been confirmed in other reports {799}.

Sinonasal non-intestinal-type adenocarcinoma

ICD-O code

B140/3

Synonyms

Sinonasal low-grade adenocarcinoma, terminal tubulus adenocarcinoma, sinonasal tubulopapillary low-grade ade-nocarcinoma.

Definition

Adenocarcinomas arising in the sinonasal tract that are not of minor salivary gland origin and do not demonstrate histopathologic features of the sinonasal intestinal-type adenocarcinoma. These adenocarcinomas are divided into low- and high-grade subtypes.

Epidemiology

Sinonasal non-intestinal-type adenocar-cinomas predominantly occur in adults but have been identified over a wide age range from 9-80 years {1044}. The average patient age at presentation of low-grade adenocarcinomas is 53 years while that of high-grade ones is 59 years {1044}. There is a slight male predominance for the low-grade adenocarcino-mas but a more marked male predilection in the high-grade ones {1044}.

Etiology

There are no known occupational or environmental etiological factors.

Localization

The low-grade non-intestinal-type adenocarcinomas predilect to the ethmoid sinus (to a lesser extent as compared with the intestinal-type), and the highgrade non-intestinal-type adenocarcino-mas predilect to the maxillary sinus

Fig. 1.13 Sinonasal high-grade non-intestinal-type adenocarcinoma. Solid areas of the tumour show marked nuclear pleomorphism as well as an area of comedo-type necrosis.

Fig. 1.14 Sinonasal (mucosal) non-intestinal-type adenocarcinoma. A Complex glandular growth and focal papillary architecture. B The glands are lined by a single layer of cuboidal to columnar appearing cells with uniform, round nuclei, single small identifiable nucleoli and eosinophilic appearing cytoplasm.

Fig. 1.14 Sinonasal (mucosal) non-intestinal-type adenocarcinoma. A Complex glandular growth and focal papillary architecture. B The glands are lined by a single layer of cuboidal to columnar appearing cells with uniform, round nuclei, single small identifiable nucleoli and eosinophilic appearing cytoplasm.

Fig. 1.15 Sinonasal low-grade non-intestinal-type adenocarcinoma. A Complex glandular growth including back-to-back glands lacking an intervening fibrovascu-lar stroma is characteristically seen. B The glands are comprised of a single layer of nonciliated columnar cells with uniform, round nuclei, granular eosinophilic cytoplasm. The cells vary from orderly linear arrangement to stratification with loss of nuclear polarity.

Fig. 1.15 Sinonasal low-grade non-intestinal-type adenocarcinoma. A Complex glandular growth including back-to-back glands lacking an intervening fibrovascu-lar stroma is characteristically seen. B The glands are comprised of a single layer of nonciliated columnar cells with uniform, round nuclei, granular eosinophilic cytoplasm. The cells vary from orderly linear arrangement to stratification with loss of nuclear polarity.

{1044}. Either tumour type may also originate in the nasal cavity, other paranasal sinuses, or in multiple sinonasal sites in various combinations {1044}.

Clinical features

For low-grade adenocarcinomas, patients primarily present with nasal obstruction and epistaxis. Pain is an infrequent feature {1044}. The duration of symptoms ranges from 2 months to five years, with a median of 5.5 months. For high-grade adenocarcinomas, the presenting symptoms include nasal obstruction, epistaxis, pain and facial deformity (e.g., proptosis). The duration of symptoms ranges from two weeks to five years with a median of 2.5 months {1044}.

Macroscopy

The appearance varies, including well demarcated to poorly-defined and invasive, flat to exophytic or papillary growths with a tan/white to pink colour and a friable to firm consistency.

Histopathology

The low-grade non-intestinal-type adenocarcinomas are circumscribed or invasive, and have a glandular or papillary growth. Numerous uniform small glands or acini are arranged in a back-to-back or coalescent pattern with little or no intervening stroma. Occasionally, large, irregular cystic spaces can be seen. The glands are lined by a single layer of non-ciliated, cuboidal to columnar cells with uniform, round nuclei which may be limited to the basal aspect of the cells or may demonstrate pseudostratification with loss of nuclear polarity. The cytoplasm is eosinophilic. Cellular pleomorphism is mild to moderate. While occasional mitot-ic figures may be seen, atypical mitoses and necrosis are absent. Variants include papillary, clear cell and oncocytic adenocarcinomas. Multiple morphologic patterns may be present in a single neoplasm. Despite the relatively bland histology, the complexity of growth, absence of myoepithelial/basal cell component, absence of encapsulation and invasion into the submucosa permit a diagnosis of malignancy to be made. The high-grade non-intestinal-type ade-nocarcinomas are invasive tumours with a predominantly solid growth pattern, but glandular and papillary patterns can also be present. These tumours are characterized by moderate to marked cellular pleomorphism, high mitotic activity, including atypical forms, and necrosis.

Prognosis and predictive factors

The treatment for sinonasal non-intestinal-type adenocarcinomas is complete surgical excision generally via a lateral rhinotomy; depending on the extent and histology of the neoplasm, the surgery varies from local excision to more radical procedures (maxillectomy, ethmoidecto-my and additional exenterations). Radiotherapy may be utilized for extensive disease or for higher-grade neoplasms. The low-grade neoplasms have an excellent prognosis, while high-grade neoplasms have a dismal prognosis with a 3-year survival rate of only approximately 20% {1044}.

Was this article helpful?

0 0
10 Ways To Fight Off Cancer

10 Ways To Fight Off Cancer

Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.

Get My Free Ebook


Post a comment