CASE 14117 Published on 04.12.2016

Tonsillar syphilis mimicking carcinoma


Head & neck imaging

Case Type

Clinical Cases


S. Santos Ochoa de Eribe1, H. Portilla-Quattrociocchi2, A. Montero de la Peña2, D. Garcia Hernandez2, I. Tobalina Larrea2, A. Alvarez Alonso2.

1Hospital Universitario Araba, Radiology; Jose Atxotegi s/n 01009 Vitoria-Gasteiz, Spain;
2Hospital Universitario Araba, Nuclear Medicine; Olaguibel 29 01009 Vitoria-Gasteiz, Spain;

42 years, male

Area of Interest Head and neck, Nuclear medicine, Lymph nodes, Adrenals ; Imaging Technique CT, PET-CT
Clinical History
A 42-year-old man presented with odynophagia for two weeks and an enlarged left laterocervical lymph node. He had been previously treated with paracetamol and ibuprofen with no improvement.
Imaging Findings
The patient underwent CT of the neck, which showed a left tonsillar mass and cervical ipsilateral lymph nodes, predominantly at level II (Figure 1). This was supplemented with a 18F-FDG PET-CT that demonstrated a hyper hypermetabolic left tonsil (Figure 2) and cervical lymph nodes (Figure 3). Furthermore, a left adrenal mass was discovered incidentally on the fused PET-CT images, concerning for malignancy (Figure 4). The patient underwent biopsy of both the tonsillar and adrenal lesions.
The tonsil demonstrated an infectious reactive process, probably luetic, and the adrenal mass was an adrenal carcinoma.
During admission the patient developed a generalized maculopapular non-itchy rash suggestive of syphilitic roseola. Upon further questioning he patient admitted to having recent unprotected oral sex. Serological tests proved positive. A diagnosis of tonsillar primary syphilis with transition to secondary syphilis was established. He was treated with benzathine penicillin 2, 400, 000 units.
Syphilis is a predominantly sexual transmitted disease caused by the spirochete bacterium, Treponema pallidum [1]. Primary syphilis begins with the development of a chancre at the site of contact (85% on the genitals and 10% anal). It heals by itself and is typically painless [2]. Extragenital manifestations are uncommon. The oropharynx is affected only in 4%, usually appearing as a single ulcer located on the lips [2, 3]. Next in frequency are tongue and tonsillar lesions, although chancres are rare at these sites [2, 4, 5]. In the tonsil, lesions appear oedematous with an eroded surface [2, 4]. Secondary syphilis typically begins weeks after the ulcer has healed. Clinical manifestations are due to haematogenous spread, causing a maculopapular rash, generalized lympadenopathy and fatigue. Tonsils at this stage can develop painful ulcers [6]. After a latent period, tertiary disease divides into gummatous syphilis (with chronic ulcers, also seen in the tonsils), cardiovascular or neurological symptoms [1, 6].

Our patient had some signs suspicious of malignancy, such as a hypermetabolic left tonsillar mass and increased FDG uptake in lymph nodes, greater than 2 cm, with a firm texture and non-tender. 18F-FDG PET-CT has proven to be a useful technique to stage neoplasms [7]. However, FDG is not a cancer-specific agent, so significant activity may be displayed in non-neoplastic aetiologies such as inflammation and infection [8].

He was incidentally diagnosed with adrenocortical carcinoma, which accounts for 2% of adrenal incidentalomas. Frequent sites of metastases are lung, liver and skeleton and up to 10% suffer from a second primary malignancy. Treatment of localized tumours consists of surgery, as in this case [9].

Large, firm and non-tender lymphadenopathy is typical of syphilis lymphadenitis [10]. Diagnosis is based mainly on Rapid Plasma Reagin (RPR) and Treponema pallidum particle assay (TTPA) tests. The TTPA is used to confirm syphilis and RPR to assess its progression and treatment efficacy [11].

Diagnosing syphilis is challenging as it mimics several other diseases. Oral manifestations of syphilis are uncommon but should be considered in the differential diagnosis of a tonsillar mass with enlarged nodes. Correlation between clinical, radiological and metabolic indices is therefore crucial. 18F-FDG PET-CT is quite sensitive but lacks specificity, consequently results should be confirmed on biopsy.
Differential Diagnosis List
Tonsillar primary syphilis
Lymphoproliferative disorders (lymphoma)
Carcinoma of the tonsil
Non-tuberculous mycobacteria
Bacterial tonsillitis
Angina Plaut-Vincent
Primary HIV infection
Orogenital herpes simplex
Pharyngeal gonorrhea
Chlamydia infection
Final Diagnosis
Tonsillar primary syphilis
Case information
DOI: 10.1594/EURORAD/CASE.14117
ISSN: 1563-4086