Histopathological profile of sinonasal lesions with brief clinical correlation: experience in a tertiary care centre

Background : Sinonasal lesions are a common finding in Otorhinolaryngology out patient department. Most commonly they present withnasal obstruction. Clinically many of these lesions resemble eachother but they have multiple differential diagnosis ranging from congenital, inflammatory, traumatic to neoplastic causes that needs histopathological confirmation. Objectives: This study was undertaken to study the various histopathological patterns of sino-nasallesions, theirclassification and relative distribution of various lesions with regard to age and sex in our setting . Material and Methods: This was a retrospective study of Sino-nasal lesions specimens thatwas received at histopathology section of Department of Pathology, Hamdard Institute of Medical Science andResearch andover a period of two years from June 2014 to May 2016. Results: A total of 62 cases of sino-nasal lesions were reported during the study period. Ageranged from 5 years to 75 years with malepredominance. Among all the lesions forty five (45) were non-neoplastic, ten (10) benign and seven (7) were diagnosedas malignant tumors. Inflammatory polyp was the commonest non-neoplastic lesion while Sinonasal Papilloma was the commonest benign lesion and Sinonasal carcinoma was themost common malignancy. Conclusions: Sino-nasal lesions comprises of wide spectrum of lesions but their presenting clinicalmanifestations are very limited. Hence, on the basis of clinical picture various nonneoplastic, benign and malignantlesions may mimic each other. Histopathological diagnosis forms the mainstay of diagnosis in these lesions whichmay even reveal clinically unsuspected rare malignancies as seen in our study.


Introduction
The nasal passage and paranasal sinuses collectively termed Sino-nasal area serves as host to a variety of diseasedconditions known as sino-nasal lesions that are commonly seen in Otorhinolaryngology outpatient department. Sinonasal area along with nasopharynx constitute the functional unit that is lined by stratified squamous epitheliu m, pseudostratified colu mnar epitheliu m and intermediate (t ransitional) epitheliu m andis principally involved infiltering, humidifying and adjusting temperature of inspired air [1,2]. Exposure of these areas to various infectiveagents, chemicals, antigens, mechanical and many other influences leads to  [3]. These lesions vary widely depending on the age, occupation and addiction habits and other environmental factors related to the patients. Thus, they provide a challenging as well as interestingarea for an in-depth study of theselesions. Most of these patients present with complaints of nasal obstruction [4]. Other symptoms include nasal discharge, epistaxis, disturbances of smell. These sinonasal lesions can have various differential diagnosis that may becongenital, inflammatory, neoplastic or traumat ic. A mong these, Polyps including in flammatory and allerg ic arethe most common sinonasal lesion. They are co mmon cause of nasal obstruction and have prevalence of about 4% of general population [5]. Other non-neoplastic lesions are

Original Research Article
Pathology Updare: Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 383 | P a g e bacterial and fungal infections. Benigntumours like papillo ma, haemangio ma, angiofib ro ma are relatively common, but malignant neoplasms are rare. Malignant tumours account for 0.2% to 0.8% of total malignancies and only 3% of all malignant tumours of upperaerodigestive tract [6]. Squamous cell carcino ma is the most common microscopic type of sinonasal neoplasmaffecting the nasal skin and nasal cavities [7]. Adenocarcinomas of various types comprise 10% to 20% of allprimary malignant neoplasms of the nasal cavityand paranasal sinuses [8]. Adenoid cystic carcino ma usuallyoccurs in the maxillary sinus and nasal cavity [8]. NHLs of the sinonasal tract are heterogeneous diseases that can beclinically aggressive [9]. Presumptive d iagnosis of these lesions can be achieved with the aid of clin ical presentationand imaging techniques but histopatho-logical examination remains the mainstay of final definitive diagnosis [10]. The present study was undertaken to analyze the spectrum of Sinonasal lesions, their age and sex distribution, briefclin ical p resentation and histopathological diagnosis. Sampling Methods: Clinical data was retrieved from histopathology requisition form / hospital records of patients presenting with sino-nasal lesion.

Materials and Methods
Sample collection: All the specimens (biopsies/surgical specimens) that were received in our histopathology section were fixed in 10% formalin , embedded in paraffin, sectioned at 3-5μ and stained with hemato xylin and eosin. Special stains like Ziehl Neelsen (ZN) and Periodic acid Schiff (PAS) stains were done wherever necessary.
Inclusion criteria: All the specimens of lesions of nasal cavity, paranasal sinuses and nasopharynx receivedat histopathology section of pathology were included in the study.

Excl usion Criteria:
Previously treated cases of sinonasal disease with recurrence were excluded fro m the study.
Statistical Method: Descriptive statistical measures were utilized to present the data.
A total of 62 cases of sinonasal lesions fulfilling these criteria were finally included in this study. Histologically the nasal masses were classified into nonneoplastic masses and neoplastic masses. Nonneoplastic masses were further subdivided as allergic and nonallergic types, and neoplastic masses were d ivided as benign and malignant lesions.

Results
A total of 62 cases presented as sinonasallesions. Amongst these, 37 were malewhile 25 cases were female. An overall male predominance was noted with M:F= 1.48:1 (Table I). Male preponderance was more marked in malignant lesions and the male to female ratio was 2.5:1 (Table I). Sino-nasallesions were commonest in the 11-20 years (16 cases) followed by equal numbers in31-40 and 41-50 year agegroup comprising 14 cases each (Table II). Maximu m nu mber of non-neoplastic masses were also seen in 11-20 yeargroup (14 cases) followed by 31-40 year age group (11 cases). Malignant tumors were most commonly encounteredequally in 41-50 and 51-60 year age (2 cases). Forty-five (45) nonneoplastic lesions, ten (10) benign lesions and seven (7) malignant tumors were diagnosed. Most of the sino-nasal lesion presented with nasal obstruction whichwas the commonest symptom fo llo wed by nasal discharge and epistaxis. Facial pain was noted in occasional cases. Inflammatory polyp (including allergic) was the most common nonneoplastic lesion with 33 cases (73.3%). Two cases of Mucormycosis, two cases of Tuberculosis and one case of Adenoid Hypertrophy were also reported amongnon-neoplastic lesion. Among the benign lesion, Sinonasal Papillo ma was the most commonly encountered lesionwith 5 cases including two cases of Inverted Papillo ma (50%). Two cases of Haemangio ma, one each of Angiofibro ma, Schwannoma and Neurofibro ma were also diagnosed histopathologically. A mong the malignancies, Sinonasal carcino ma was the most common co mprising of t wo cases (28.5%). We also encountered few raremalignancies which included one case each of Nonkeratinizing undifferentiated nasopharyngeal carcinoma, Basaloid Squamous cell carcino ma, Adenoid cystic carcino ma, Teratocarcinosar coma and Non Hodgkin's Ly mphoma during our 2 years study (Table III).

Original Research Article
Pathology Updare: Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 384 | P a g e

Discussion
Sino-nasal lesions form a co mplex group of lesions with a broad spectrum of clin ical and histopathological features. A totalnumber of 62 cases were included in our study. Age of the patientsranged from 5 years to 75 years. In thepresent study, sino-nasal lesions were predominant in males, demonstrating a male to female rat io of 1.48:1. Themale preponderance was more marked in malignancies (M:F= 2.5:1). Many authors have observed similar male preponderance [7,11,15], while only in few studies sino-nasal lesions were mo re common in females [12]. The mostcommon age groups for sino-nasal lesions in our study was second decade followed by 3 rd and 4 th decade. Similar finding was observed by A.Lathi et al [7]. In our study non-neoplastic, benign and malignant nasal lesions were common ly encountered in [11][12][13][14][15][16][17][18][19][20] year, 31-50 year and 41-60 year age group respectively which was in concordance with Parajuli et al [13]. Lathi et al concluded that malignant nasal masses are rarely encountered before fourth decade of life [7]. Nasal obstruction was the most common clin ical presentation, follo wed by rhinorrhoea. Similar presenting features were observed in other studies [4,12,14].
In our study, inflammatorypolyps (including allergic) were the most common nasal non-neoplastic masses. This observation was similar to several other studies [7,11,15,16]. Nasal polyps result from chronic inflammation of thenasal and sinus mucous membranes. Their exact pathogenesis is not known, however a strong association withallergy, infection, asthma and aspirin sensitivity has been imp licated [5,17]. Microscopically, the epithelial lining ofnasal masses is of the respiratory type unless squamous metaplasia hasoccurred [18].
Among other non-neoplastic lesions included in our study were mucormycosis (4.4%) which on microscopy showedbroad non-septate hyphae that were arranged irregularly ( Figure 1) [16,21]. Due toits rarity and nonspecific clin ical presentation, clinical diagnosis of nasal tuberculosis may be missed that may lead todelay in proper treatment.In such cases histopathology of the nasal lesions play an important role in the timely diagnosis of sinonasal tuberculosis [22]. Our study did not show any case of rhinoscleroma and rh inosporidiosisunlike the study of Lathi et al [7].

Figure-1: Photomicrograph showi ng broad aseptate hyphae wi th irregular branching (H&E Stai n; 40x)
Among benign lesions, sino-nasal papillo ma was the most common lesion including its morphological variant. Wereportedfive (50%) cases of sino-nasal papillo maincluding 3 cases of squamous and 2 cases of inverted papillo ma [ Figure 2] which is a morphological variant of sino-nasal papillo ma. This was similar to the study by Amit et alwho reported one case of Inverted papillo ma andtwo cases of Sinonasal papillo ma [23]. Narayana Swami et alreported 13% of inverted papillo ma in his study [24]. Sinonasalpapillo mas account for 0.5-4% of all nasal tu mors [25]. Transformation of sinonasalpapillo mas into malignancy has been described in inverted papillo ma andoncocyticpapillo mas, but not in exophyticpapillo mas [26]. Hemangio ma (2 cases) were reportedin 20% o f the benign lesions. Both of them were found to be arising fro m nasal septum. Similar findingswere reported by other authors too [12.27].

Original Research Article
Pathology Updare: Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 386 | P a g e  A single case of Angiofibro ma was reported in a 16 year old male child that constituted 10% of benign sinonasallesions in our study. This corresponds with the study ofA Lathi et al [7]. Wealso reported oneunusual case of schwannoma ( Figure 3) in a 40 year old male patient presenting as mass in right nasal cavity with clin ical suspicionof inverted papillo ma. Gulaeria et al also reported one case of Schwannoma [27]. Sch wannomas of the sino-nasaltract are very infrequent, representing less than 4% of the schwannomas of the head and neck region [28]. One caseof Neurofibro ma were also detected in a 16 year female which is also infrequent in these locations. Battacharya et alalso reported a single case of neurofibroma in h isstudy [20].
Among malignantneoplasms a total of 7 cases were reported. Four cases were seen after the age of 40 years whiletwo cases were in the 21-30 years age group. Male: Female ratio was 2.5 :1. Two cases of Sinonasal carcinoma including one Nonkeratin izing Squamous cell carcino ma and one Papillary variant of intestinal type Adenocarcinoma (Figure 4) were reported. Intestinal-type adenocarcinoma (ITAC) are responsible for less than 4% of the total malignancies of this region [29]. These tumors are co mmon in workers in the hardwood and shoeindustries. IHC was also done in this case which showed positivity for CK20. Papillary ITAC may have the bestprognosis, as it typically behaves as locally destructive lesion with a limited tendency for regional or d istantmetastases [8,30].

Original Research Article
Pathology Updare: Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 387 | P a g e  One case of undifferentiated nasopharyngeal carcino ma was seen in a 28 year old female. A single case of Adenoid cystic carcino ma ( Figure 5) was reported in a 42 yearold male patient who presented with Right nasal obstructionand facial pain. PAS and Mucin stains were positive in this case. One case of basaloid squamous carcinoma wasreported in a 75 year female. Another single rare case of Sinonasalteratocarcinosarcoma was reported in a 26 year male and one case ofNon-Hodgkin's ly mphoma was reported in a 58 year male during the study period. These arevery uncommon neoplasms of sino-nasal region. Gu leria et al reported two cases of nasopharyngeal carcino ma, fourcases of Adenoid cystic carcino ma and one case of Non hodgkin's Ly mpho ma in hisstudy [27].
Thus thisstudy helped us in providing an insight into the varied clinicopathological spectrum of nasal masses.

Conclusions
Sino-nasal lesions comprise of wide spectrum of lesions but their presenting features are mostly overlapping andlimited in nu mber. As a result, they pose diagnostic dilemma, as clin ically even benign and malignant sinonasallesions may appear as non-neoplastic thus leading to delay in proper d iagnosis and early treat ment.
Hencehistopathological evaluation forms essential part of work up that helps in arriving at definitive d iagnosis. Ashighlighted in our study, itmay even reveal lesions such as tuberculosis that are rare in this location and clin icallyunsuspected rare malignancies which were not suspected initially by the clinicians.Thus histopathology

Original Research Article
Pathology Updare: Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 388 | P a g e is a simp leand cost effective tool that help in categorization of different sino-nasal lesions according to various parameters.
Author inclusion criteria -Dr. Nehal was responsible for the literature search and drafting of manuscript. Dr. Sabina was involved in reviewing, ed iting and interpretation of smears. Dr. Jaseem was involved in reviewing of the manuscript. Dr. Su jata was involved in reviewing the manuscript and also its editing.
Fundi ng: Nil, Conflict of i nterest: None init iated, Permission from IRB: Yes