Advertisement

The key role of 18F-FDG PET/CT for correct diagnosis, staging, and treatment in a patient with simultaneous NPC and TB lymphadenitis: case report

Abstract

Aims and background

The coexistence of tuberculous lymphadenitis of the neck region and head and neck cancer is extremely rare. In this clinical situation, the use of positron emission and computed tomography using fluorine-18 fluorodeoxyglucose (18F-FDG PET/CT) may facilitate the differentiation between malignancy and tuberculosis.

Case report

We present a case of an Eastern European man with nasopharyngeal cancer and concurrent tuberculous lymphadenitis.

Results and conclusion

The adequate and critical interpretation of pretreatment 18F-FDG PET/CT scan addressed the multidisciplinary team to the proper staging of disease and to the correct therapeutic approach.

Tumori 2016; 102(Suppl. 2): e22 - e25

Article Type: CASE REPORT

DOI:10.5301/tj.5000432

Authors

Renato Micera, Nicola Simoni, Mario De Liguoro, Federica Vigo, Claudia Grondelli, Marco Galaverni, Massimo Roncali, Maria Pagano, Cinzia Iotti

Article History

Disclosures

Financial support: None.
Conflict of interest: None.

This article is available as full text PDF.

Download any of the following attachments:

Introduction

In Italy, as in many Western European countries, tuberculosis (TB) is a relatively rare disease, with a prevalence of 6.7 cases/100,000 inhabitants in 2013. However, in some parts of Eastern Europe, the incidence of TB continues to be high (1).

Lymphadenitis is the most commonly occurring form of extrapulmonary TB. Cervical lymph node involvement is the most frequently observed, but inguinal, axillary, mesenteric, mediastinal, and intramammary adenopathies have also been described (2).

Nasopharyngeal cancer (NPC) is rare in Europe, with an annual crude incidence rate of 1.1 per 100,000 (3).

In most cases, cervical lymph node involvement is the main symptom of NPC. Up to 75% of patients show enlarged cervical nodes at presentation and bilateral lymphadenopathy may be seen in 80% of patients. Although the retropharyngeal lymph nodes are considered the first echelon nodes, 35% of metastasis bypass them to directly reach the internal jugular nodes (level II).

Falagas et al (4) described 3 different types of association between malignancy and TB: 1) the development of cancer on the background of a previous tuberculous infection; 2) the concurrent existence of TB and malignancy in the same patient or clinical specimen; and 3) the diagnostic challenges arising from the multifaceted presentations of these 2 disorders.

In the staging workup of NPC, positron emission and computed tomography using fluorine-18 fluorodeoxyglucose (18F-FDG PET/CT) has excellent diagnostic performance for detecting lymph nodal and distant metastases (5). 18F-FDG PET/CT may facilitate the identification of extrapulmonary TB, the staging of TB, and the differentiation between malignancies and TB (6).

In this article, we report the key role of 18F-FDG PET/CT for correct diagnosis, staging, and treatment in a man with simultaneous NPC and TB lymphadenitis.

Case report

A 36-year-old Romanian man was admitted to our hospital for persistent headaches. No other symptoms were present. Magnetic resonance imaging of the brain revealed a lesion of the right wall of the nasopharynx with infiltration of the parapharyngeal space. Biopsy documented an undifferentiated carcinoma. At clinical examination, no cervical palpable lymph nodes were present. Contrast-enhanced computed tomography (CECT) of head and neck and thorax confirmed the nasopharyngeal lesion and showed multiple bilateral nodes (right levels II, III and left levels II-IV) with characteristics suspicious for metastases. Hence, the disease was staged cT2N2M0 according to Union for International Cancer Control/American Joint Committee on Cancer, 7th edition, and the patient was directed to a curative radiation therapy course with concomitant chemotherapy. A CECT simulation and 18FDG-PET/CT scan in treatment position were planned. Our intent was to deliver the highest dose (69.96 Gy/2.12 Gy fraction) to the primary and to the clinically involved nodes, an intermediate dose (59.4 Gy/1.8 Gy fraction) to the high-risk regions (levels II-V and VII bilaterally), and a lower dose (54 Gy/1.65 Gy fraction) to the levels Ib bilaterally according to Radiation Therapy Oncology Group 0615. In our center we use pretreatment 18F-FDG PET/CT scan in all patients with NPC. The purpose is to obtain additional information for neck and distant staging or second primary and to improve the accuracy of target volume delineation (7).

In our patient, in addition to the primary lesion, 2 bilateral nodes of level II, 1 left level IV node, and multiple right axillary nodes were FDG avid (mean SUVmax 5.1, range 6.9-3.5). The maximum activity was observed in the primary lesion (SUVmax 6.8) and in the left level II node (SUVmax 6.9). The SUVmax of the axillary node was 4.8 (Fig. 1). Due to the fact that axillary involvement is an unusual metastatic site for NPC, the multidisciplinary team reviewed the case and further investigations were planned. The patient underwent a neck ultrasound with morphologic evidence of inflammatory-reactive lymphadenitis. Moreover, ultrasound-guided fine needle aspiration cytology examination of the neck nodes (level II bilaterally) and excision of 3 axillary nodes were performed. No tumor metastases were detected in the axilla or in the neck nodes. Granulomatous inflammation with focal areas of necrosis was found and microbiologic examination with Ziehl-Neelsen and Grocott stains were positive as well as QuantiFERON test. These findings led to the diagnosis of extrapulmonary TB (i.e., tuberculous lymphadenitis).

Pre treatment 18 F-FDG PET/CT.

The NPC was downstaged to cT2N0M0. With the definitive radiotherapy treatment, only the primary lesion received the highest dose, whereas levels II, III, Va, and VII received 59.4 Gy (dose adequate to control a microscopic disease) and levels IV and Vb 54 Gy (Fig. 2). The level Ib was not treated. The treatment was performed with a simultaneous integrated-boost intensity-modulated technique using helical tomotherapy. Concomitant chemotherapy was not prescribed ­because of the concurrent TB. Antitubercular therapy (isoniazid, ethambutol, rifampin, and pyrazinamide) was begun 2 weeks before radiotherapy and lasted for 6 months.

Orthogonal views of dose distribution.

Despite the short period, at 1 year since the end of the radiotherapy, there was no clinical or radiologic evidence of NPC or TB (Fig. 3).

Post treatment 18 F-FDG PET/CT.

Discussion

There is a well-known association between TB and malignancy, such as the development of cancer on the background of a previous TB infection or as the concurrent existence of TB and malignancy (5). Lymphadenitis of the head and neck region is the most commonly occurring form of extrapulmonary TB, hence the coexistence with head and neck cancer poses a diagnostic dilemma. Proper assessment of the disease is important when deciding on the correct treatment regimen.

We present a case of an Eastern European man with NPC and concurrent extrapulmonary TB. To our knowledge, this is the first case of coexisting NPC and TB cervical lymphadenitis in the English literature.

Falagas et al (4) reported 47 cases, 1 case series, and 2 retrospective studies that focused on the coexistence of malignant tumors with TB infection in the same site. Only one case in which a tongue cancer occurred synchronously with cervical TB lymphadenitis was described (5, 8). Two other articles reported coexisting tuberculous lymphadenitis with head and neck malignancy, one with a soft palate cancer (9) and the other with a larynx cancer (10).

18F-FDG PET/CT has a growing role in the diagnosis and management of NPC, both for staging purposes and for improving the accuracy of gross tumor volume delineation. In extrapulmonary TB, PET/CT can help in demonstrating lesion extent, detecting additional lesions missed on morphologic imaging, and in serving as a guide for biopsy with aspiration for culture (6). With the use of SUV, it is impossible to distinguish tuberculous lymphadenitis from metastatic lymph node involvement; however, certain patterns of lymph node tracer distribution provide useful clues helping the diagnosis. In our case, the doubt of coexisting infection resulted only from the distribution of the nodal uptake (right axillary region), extremely unusual for NPC. Therefore the use of a total body examination such as PET/CT directed the multidisciplinary team towards the correct diagnosis and subsequent treatment strategy. The change in the radiation treatment induced a reduction of high-dose and high-risk volumes, resulting in a lower risk of acute and late toxicity, particularly of parotid and submandibular glands. Concomitant systemic therapy, which could have worsened the risk of tuberculous infection, was not administered. However, it is necessary to underline that in absence of atypical lymph nodal location in the axillary region, PET-CT could have led us to consider all the suspected and border line nodes metastatic, and therefore no other investigations would have been planned.

In conclusion, this case highlights the importance of adequate and critical interpretation of 18F-FDG PET/CT, because an incorrect diagnosis can be detrimental for patients with cancer and coexistent TB, especially for head and neck squamous cell carcinoma and tuberculous lymphadenitis. We also emphasize the need to consider TB in the differential diagnosis with malignancy in patients from endemic areas. For these patients, pathologic confirmation of the suspected adenopathy is recommended.

Disclosures

Financial support: None.
Conflict of interest: None.
References
  • 1. Murray CJL Ortblad KF Guinovart C et al. Global, regional, and national incidence and mortality for HIV, tuberculosis, and malaria during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet 2014 384 9947 1005 1070 Google Scholar
  • 2. Golden MP Vikram HR Extrapulmonary tuberculosis: an overview. Am Fam Physician 2005 72 9 1761 1768 Google Scholar
  • 3. Chan AT Grégoire V Lefebvre JL et al; EHNS–ESMO–ESTRO Guidelines Working Group. Nasopharyngeal cancer: EHNS-ESMO-ESTRO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol 2012 23 Suppl 7 vii83 vii85 Google Scholar
  • 4. Falagas ME Kouranos VD Athanassa Z Kopterides P Tuberculosis and malignancy. QJM 2010 103 7 461 487 Google Scholar
  • 5. Shen G Zhang W Jia Z Li J Wang Q Deng H Meta-analysis of diagnostic value of 18F-FDG PET or PET/CT for detecting lymph node and distant metastases in patients with nasopharyngeal carcinoma. Br J Radiol 2014 87 1044 20140296 Google Scholar
  • 6. Vorster M Sathekge MM Bomanji J Advances in imaging of tuberculosis: the role of ¹⁸F-FDG PET and PET/CT. Curr Opin Pulm Med 2014 20 3 287 293 Google Scholar
  • 7. Grégoire V Chiti A Molecular imaging in radiotherapy planning for head and neck tumors. J Nucl Med 2011 52 3 331 334 Google Scholar
  • 8. Chaturvedi P Pai PS Chaukar DA et al. Extensive tubercular neck lymphadenopathy in a man with early-stage tongue cancer. Nat Clin Pract Oncol 2007 4 12 726 728 Google Scholar
  • 9. Erkul E Cincik H Interesting association of squamous cell carcinoma of soft palate and tuberculous lymphadenitis. Eur Arch Otorhinolaryngol 2015 May 272 5 1295 8 Google Scholar
  • 10. Al-Zahid S Singh V Tuberculous cervical lymphadenitis in a patient with laryngeal carcinoma. J Laryngol Otol 2010 124 1 90 92 Google Scholar

Authors

Affiliations

  • Radiation Therapy Unit, Department of Oncology and Advanced Technology, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, Reggio Emilia - Italy
  • Nuclear Medicine Unit, Department of Oncology and Advanced Technology, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, Reggio Emilia - Italy
  • Medical Oncology Unit, Department of Oncology and Advanced Technology, Azienda Ospedaliera ASMN, Istituto di Ricovero e Cura a Carattere Scientifico, Reggio Emilia - Italy

Article usage statistics

The blue line displays unique views in the time frame indicated.
The yellow line displays unique downloads.
Views and downloads are counted only once per session.

No supplementary material is available for this article.