Primary small cell neuroendocrine carcinoma of the tongue: Discussion of an unusual entity with review of literature

Mukta Meel; Arpita Jindal; Mukesh Kumar; Alka Mittal

doi:10.4103/IJPM.IJPM_1015_20

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Year : 2021 | Volume : 64 | Issue : 4 | Page : 844-846

Primary small cell neuroendocrine carcinoma of the tongue: Discussion of an unusual entity with review of literature

Mukta Meel¹, Arpita Jindal¹, Mukesh Kumar², Alka Mittal¹
¹ Department of Pathology, SMS Medical College, Jaipur, Rajasthan, India
² Department of Neurosurgery, SMS Medical College, Jaipur, Rajasthan, India

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Date of Submission	23-Aug-2020
Date of Decision	08-Oct-2020
Date of Acceptance	21-Nov-2020
Date of Web Publication	20-Oct-2021

How to cite this article:
Meel M, Jindal A, Kumar M, Mittal A. Primary small cell neuroendocrine carcinoma of the tongue: Discussion of an unusual entity with review of literature. Indian J Pathol Microbiol 2021;64:844-6

How to cite this URL:
Meel M, Jindal A, Kumar M, Mittal A. Primary small cell neuroendocrine carcinoma of the tongue: Discussion of an unusual entity with review of literature. Indian J Pathol Microbiol [serial online] 2021 [cited 2023 Mar 21];64:844-6. Available from: https://www.ijpmonline.org/text.asp?2021/64/4/844/328511

Introduction

Small cell neuroendocrine carcinoma (SNEC) is the most common pulmonary neoplasm and rare at extra pulmonary site accounting for 0.1–0.4% of all malignancies and 2.5–4% of small cell carcinomas (SCCs). Extensive literature search has revealed only seven cases of small cell neuroendocrine tumor of the tongue [Table 1].^{[1],[2],[3],[4],[5],[6],[7]} Herein, we present the eighth case of a SNEC in a 32-year-old male on the base of tongue.

Table 1: Clinical characteristics of reported cases of small cell neuroendocrine tumour of tongue

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Case Report

A 32-year-old male presented to the otolaryngology department with difficulty in swallowing to solid food and a painless non-ulcerated swelling on the right base of tongue since 1 and 1/2 year, gradually increasing in size and with 1-month history of swelling on right side of neck. He had history of smoking and chewing betel nuts and no significant family history. On physical examination, oral cavity revealed a large growth at the base of tongue with bilateral cervical palpable nodal mass with unremarkable systemic examination. The fine needle aspiration of the neck node revealed small rounded cells with scant cytoplasm, high N/C ratio and nuclei with finely granular chromatin, mild pleomorphism, nuclear molding, and mitotic activity suggestive of malignant round cell neoplasm. MRI Neck demonstrated large altered signal intensity mass measuring 2.8 × 3.6 × 4.8 cm arising from the posterior third of right side of tongue with large exophytic soft tissue component causing partial oropharyngeal obstruction. Multiple discrete, conglomerate bilateral cervical lymph nodes were noted at level IB, II, III, IV. Laboratory findings, (complete blood count, blood biochemistry, and urine analysis) were within normal limits. To evaluate the tongue mass, an incisional biopsy was performed. Histological examination revealed a malignant neoplasm composed of tumor cells arranged in solid nests and cords, with brisk mitotic activity and necrosis. The tumor cells showed ovoid-to spindle shaped nuclei, fine granular chromatin, inconspicuous nucleoli, and scant cytoplasm [Figure 1]a and [Figure 1]b. Immunohistochemically, the tumor cells were positive for cytokeratin (PanCK), thyroid transcription factor-1 (TTF-1), and neuroendocrine markers, chromogranin A and synaptophysin and negative for CD3, CD20, CD30, CD99, p63, and CK 20 [Figure 2]a, [Figure 2]b, [Figure 2]c, [Figure 2]d. The Ki-67 labelling index was 70%. A complete workup, including computed tomography scans of chest and abdomen, and positron emission tomography proved negative in detecting any other tumoral lesion. The patient underwent bronchoscopy with synchronous bronchopulmonary aspiration, in which the cytological result was normal. In consideration of these findings, a diagnosis of primary SNEC of tongue with neck lymph node metastasis was made. Patient was managed by chemotherapy and had completed three cycles of EP regimen every 3 weeks (inj. Cisplatin 100 mg and inj. Etoposide 150 mg for 3 consecutive days) followed by concomitant chemo-radiotherapy. Following 2 months of diagnosis, patient developed subcutaneous and liver metastasis which was never seen in previously reported small cell tongue carcinoma cases. On follow-up, patient died because of disease after 1 year of diagnosis, representing aggressiveness of tumor.

Figure 1: (a) Solid tumoral tongue mass showing nests of small cell carcinoma infiltrating sub mucosa and squamous epithelium; (b) Small cell carcinoma composed of small hyper-chromatic cells, including mitotic figures and a central area of necrosis (H and E, 40×, 400×)

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Figure 2: (a) Tumour cells showing cytoplasmic immuno-reactivity for Synaptophysin (40×); (b) Tumour cells showing nuclear positivity for TTF 1 (40×); (c) Tumour cells showing cytoplasmic granular positivity for PanCK (400×); (d) Small tumour cells are immunonegative for P63 & positive for internal control (40×)

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Discussion

Cancers of the base of the tongue are relatively rare and predominantly occur in males in fifth to seventh decade of life. The significant risk factors for the development of tongue cancers are tobacco, alcohols abuse, and human papillomavirus (HPV) infection. Histologically, almost all oropharyngeal cancers are squamous cell carcinomas and very rarely any other histology is seen. The literature has suggested that origin of oral neuroendocrine carcinoma is either from neuroendocrine cells found in the oral squamous epithelium or pluripotent cells within the squamous epithelium and minor salivary gland. The histopathological characteristics of present case of small cell (neuroendocrine) carcinoma of the tongue were those of classic small cell carcinoma (SCC). In this context, immunohistochemistry is useful to exclude other possible diagnosis. Our case demonstrated positivity with neuroendocrine markers and TTF-1, but not stained with CK20. TTF-1 positivity can be detected in metastatic SCC of the lung, but in current case, with the help of radiologic and cytological respiratory system examinations, the possible origin of the lung was eliminated. Considering the differential diagnosis, small cell variant of squamous cell carcinoma of the tongue arising from the surface squamous epithelium was ruled out by negative p63 staining. The patient was thoroughly investigated to exclude primary at any other site. Hence, a diagnosis of primary small cell carcinoma of tongue was made. Extra pulmonary small cell cancer is relatively chemo sensitive, so patients are treated with Platinum- based chemotherapy regimens similar to small cell lung cancer. The clinical course in these patients is more aggressive and often recurrence is seen. In present case the patient had initially subcutaneous and liver metastasis, & later died of due to disease highlighting aggressiveness of tumor.

Conclusion

The correct diagnosis of intraoral SNECs was formed by thorough clinical evaluation excluding metastasis and combination of morphological and immunohistochemical analysis. As no standard treatment protocol exists, clinicians and pathologists must be aware of this rare entity of SNEC of oral cavity because it is an aggressive malignancy with high propensity of local recurrence and metastatic spread. To predict the behavior as well as constituting a consensus on treatment and its outcomes it is essential to report an institution's experience for primary SNEC of tongue.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Yoshida H, Onizawa K, Hirohata H. Neuroendocrine carcinoma of the tongue: Report of a case. J Oral Maxillofac Surg 1995;53:823-7.
2.	Singla A, Singla A, Gallagher R. A rare case and literature review of primary neuroendocrine carcinoma of the tongue. J Surg Case Rep 2014. doi: 10.1093/jscr/rju084.
3.	Latif N, Imtiaz S, Wang B, Rana F, Wolfson D. Primary small cell carcinoma of the tongue. J Cancer Sci Ther 2012;S5:007.
4.	Cymerman JA, Kulkarni R, Gouldesbrough D, Mccaul J. Small cell neuroendocrine tumour of the anterior tongue: A case report. Int J Surg Case Rep 2013;4:53-5.
5.	Khurana A, Singh H, Chauhan A, Mukesh. Neuroendocrine tumour of base of tongue: Treatment strategies of rare entity. J Cance Res Ther 2012;8(Suppl 3):S166. Doi:10.1093/jscr/rju084.
6.	Esmati E, Babaei M, Matini A, Ashtiani MSM, Hamed EA, Nosrati H, et al. Neuroendocrine carcinoma of the tongue. J Cancer Res Ther 2015;11:659.
7.	Khurana A, Kaur P, Chauhan AK, Sen R, Singh S. Small cell neuroendocrine tumour of base of tongue- treatment strategies of a rare entity. J Oral Health Comm Dent 2014;8:181-3.