Not all swellings are dental abscesses: A cautionary tale

Case presentation

A 48-year-old female patient presented to the emergency department with a right-sided facial swelling in November 2018. She described a 6-week history of persistent swelling, but reported a variably sized swelling being present for up to 3 months. Over this period, she had visited her general medical practitioner (GMP) multiple times, who had prescribed her two courses of co-amoxiclav. She had also intermittently seen her general dental practitioner (GDP), where she was being treated for an abscess associated with retained roots in the upper-right quadrant. During this time, there had been an ongoing discussion between the GMP and GDP as to whether the origin of infection was her maxillary sinus or a dental cause. The patient had attended her GDP the same morning, where incision and drainage had been attempted, but failed. She had significant pain but declined regular analgesia. She did not report any visual disturbances, motor or sensory changes.

She had a medical background consisting of well-controlled asthma, frequent sinusitis and ‘white coat’ hypertension. She reported allergies to doxycycline and many food and drug preservatives.

On examination, an obvious swelling was noted on the right cheek (Figure 1). This was firm, painful and hot, extending across the right maxilla and zygoma. There was some extension to the lower eyelid. She had no difficulty opening or closing her eye. Both her trigeminal and facial nerves appeared to be fully functional. Intra-orally, an associated swelling was evident in the buccal sulcus of the upper-right quadrant. This, too, was tender, erythematous and relatively firm. There was evidence of a heavily carious UR5 and retained roots of the UR6 and UR7.

The patient had brought a print-out of her orthopantomograph (OPT) from her GDP, which demonstrated retained roots in the upper-right quadrant. There also appeared to be an associated large peri-apical radiolucency, extending into the sinus with loss of normal sinus architecture. The provisional diagnosis based on these findings was acute peri-apical periodontitis and abscess associated with the retained roots, with significant concern over the appearance of the maxillary antrum. Incision and drainage was attempted in the emergency department; however, no drainage could be achieved despite extensive dissection. She was given amoxicillin and metronidazole and advised to return to the oral and maxillofacial surgery department the following day.

Investigations and outcome

A repeat OPT (Figure 2) clearly identified a large radiolucent lesion extending from the mesial aspect of the UR8 to the distal region of UR3. This extended through the maxilla and the maxillary sinus. There was also evidence of complete bony destruction in these areas and ‘floating’ teeth. The patient, however, felt that her swelling had reduced and declined extraction of the retained roots. The OPT raised sufficient concern for a CT scan (Figure 3).

The patient re-attended with increased mobility of her UR4 and UR5 teeth. A biopsy was undertaken of the buccal swelling and was ultimately inconclusive, representing inflammatory tissue.

The patient attended for a repeat biopsy on Christmas Eve 2018, but refused due to the timing, which delayed the repeat biopsy by 1 week. In January 2019, a repeat biopsy was taken, which ultimately confirmed a squamous cell carcinoma (SCC) of the right maxillary antrum. The CT and MRI scans demonstrated invasion into the orbit, skin of the eyelid, fat of the cheek, pterygoid plates, infra-temporal fossa, medial pterygoid and nasal canal (Figures 3 and 4). Enlarged nodes were also present in Level IIa in the right neck. The SCC was staged radiographically as T4aN2M0.

Treatment options were discussed with the patient:

The patient initially opted for chemotherapy followed by radical radiotherapy. However, when she was due to attend for her planning appointment, she decided not to pursue medical treatment, preferring to change to an alkaline diet, and declined any further follow-up. She subsequently succumbed to her cancer.

Discussion

Cases of head and neck cancer are increasing.¹ In males, the largest proportion of head and neck cancers occur in the larynx, while in females, the most common site is the tongue.¹ Carcinomas of the maxillary antrum are rare, and account for only 0.2% of malignancies and 1.5% of head and neck malignancies.² Risk factors for carcinomas of the maxillary sinus include smoking, a history of chronic sinusitis, air pollution and exposure to certain chemical substances, such as formaldehyde, chromium or nickel.⁵

The most common presenting symptoms are pain (59%), oral symptoms (40%) and facial swelling (38%).⁶ Owing to patients primarily experiencing oral or dental symptoms, many will attend at their GDP before their GMP. Many oral/dental symptoms may be attributed to other causes, particularly dental pathology, such as in this case. The presence of retained roots and caries proved to be misleading, and masked the true diagnosis. With delays in diagnosis owing to non-descript symptoms, it is not unsurprising that up to 71% of patients present with Stage IV disease, thus making management extremely difficult.⁶ This could be explained by the nature of growth of these tumours within the void of the sinus itself. Symptoms only start to present once the tumour has eroded through the maxillary sinus walls. With the growth of the tumour, patients can develop a wide variety of symptoms, which are often subtle in nature. Dental symptoms may include intra-oral swelling, pain, mobility, loss of teeth or even non-healing sockets following extraction. The patient may also report symptoms similar to those experienced in sinusitis, such as a blocked nose and nasal discharge. Altered sensation of the cheek/upper lip/teeth/gingivae may be apparent due to compression of the infra-orbital nerve. If the tumour grows towards the eye, then the patient may experience oculomotor difficulties, altered globe position and restricted movement, even without the direct involvement of the 3rd and 4th cranial nerves.

Diagnosis is usually achieved through histological assessment of biopsies. Although these patients tend to present late, the incidence of lymph node involvement from maxillary sinus carcinomas is low, at around 9%.⁷ It is important to note that out of these, SCCs account for the highest number of lymph node metastasis. Management of these tumours can be very challenging owing to the close anatomical location to vital structures, such as the skull base, brain, orbit and major arteries.⁸

Overall survival rates are still languishing at around 50%, with little change over the last few decades. For example, Stage I tongue cancers, have a 5-year survival of around 80%, as opposed to a Stage IV cancer, which is around 15%.⁹ When considering maxillary antrum carcinomas specifically, SCCs have a survival rate of around 29%, with over half the patients presenting with Stage III or IV tumours.⁴ This demonstrates the importance of early recognition and referral.

With the majority of patients presenting with Stage IV disease, effective recognition and early referral are important. Delay in referral could stem from patient or professional delay.¹⁰ Patient delay is typically due to lack of awareness of the key symptoms, or often denial. GMPs and GDPs are often the first point of contact for these patients. There does appear to be sufficient awareness of smoking as a risk factor for head and neck cancer, with 97% of medical practitioners acknowledging this as a carcinogen.¹¹ However, only 79% identified alcohol as a risk factor for oral cancers.¹¹ Arguably, GDPs should have a greater awareness of these risk factors, but worryingly only 50% of GDPs enquired about these habits, and only 30% offered education to patients,¹² whereas 87% of GMPs enquired.¹⁰ The awareness of pre-malignant lesions also seems generally below expected: 72% of GMPs and 79% of GDPs considered leukoplakia to be ‘very important’ in the development of oral cancer; however, only 22% of GMPs and 66% of GDPs identified erythroplakia as being important. As erythroplakias are known to have a higher risk of malignancy, this potential gap in confidence and knowledge may lead to delays and missed referrals. With regards to maxillary antrum tumours, cheek swelling is often the first symptom at presentation (79%).⁴ Other red flag signs include paraesthesia and pain/swelling without obvious pulpal or periodontal pathology. Radiographic signs include irregular bone resorption with ‘floating teeth’, poorly defined opacification over the antrum and loss of the antral walls.^8,13

The question then arises: why is there a delay in patient referral? First, patient barriers have to be considered. Some patients have expressed financial barriers preventing dental attendance.¹¹ Beyond this, we need to consider clinical barriers. It is reported that between 58% and 84% of GDPs routinely do a soft tissue examination.^10,11 A lack of time in appointments has also been identified as an obstacle, with 47% of practitioners stating they lacked clinical time to conduct an thorough oral examination.¹¹ Additionally, confidence in identifying concerning lesions also appears to be a major problem. Only 15% of GMPs and 37% of GDPs considered themselves to be confident at identifying pre-cancerous or cancerous lesions, which, coupled with the varying knowledge regarding which lesions are concerning, contributes to the risk of delayed referral.¹¹ Referral practices are also highly variable. The assumption that delays in presentation equate to a more advanced cancer should be avoided, as many patients will present when they become symptomatic.¹⁴ However, this increases the necessity for opportunistic screening by GDPs and, to a lesser degree, GMPs. Patient delays in presenting have been recorded at between 10 and 13 weeks.^10,15

This case identifies multiple key issues. GMPs and GDPs need to receive more training and have raised awareness of oral and antral cancer signs and symptoms. GMPs are usually the first point of contact for many of these patients, and therefore, should have a basic awareness of when to refer. NICE guidelines additionally, suggest onward referrals to dentists as the majority of swellings in this region will be of dental origin. However, other considerations, such as cost of attending a GDP, may be a factor impeding early attendance of patients. GDPs have a large responsibility in routine screening of patients at regular dental check-ups, and therefore should be confident in identifying suspicious lesions. GMPs and GDPs should consider a maxillary antrum tumour as a differential diagnosis where red flag features (including paraesthesia, unexpected tooth mobility and ocular changes) are present – especially if other obvious causes have been excluded.