**4. Clinical presentation**

Clinical signs and symptoms will depend on the location of the tumor, its size, and growth rate. The vast majority of patients, up to 70–75%, present with local swelling, associated with pain in more than one-third of patients. This may be followed by facial dysesthesia in about 30% and loose teeth in about 15% [13, 16]. In fact, in Patel's et al. [15] series, up to 27% had infraorbital nerve paresis (V2). Other manifestations include trismus, nasal obstruction or epistaxis, and/or headache, depending on their subsite.

HNOS are tumors that usually report rapid growth, and on average the time of presentation at consultation is 2–6 months [15].

Physical examination usually identifies a non-painful mass, fixed to the underlying bone, and it is important to note that the mucosa and superficial soft tissue may be normal or with some very slight alteration. The size can be variable, from an initial tumor, as seen in **Figure 1**, showing a patient from our institution who consulted with a relatively small swelling in right maxillary, hard, with bony consistency, in which we can see a slight irritation of the mucosa, to an obvious enlargement and bone

**Figure 2.** *Locally advanced maxillary osteosarcoma on a 48-year-old male.*

destruction, as we see on **Figure 2**, with a patient with significant involvement of the maxillary bone and adjacent soft tissue.

In fact, in Guadagnolo's et al. cohort [10], the median tumor size at presentation was 5.5 cm with a range between 1 and 15 cm. However, large series [8] report tumors smaller than 6 cm in 79%, with the majority being between 3 and 6 cm (41–44%), with no significant differences according to anatomic site. According to Granowski-LeCornu et al. [16], increasing tumor size was associated with decreased overall survival (P = .0167).

In addition, although HNOS patients present normally with tumors in the described size ranges, it is necessary to take into account that they are fast-growing tumors, as we see in **Figure 3** showing mandibular OS of the left retromolar trigone at presentation (**Figure 3a**) and its growth in 3 weeks from the first consultation (**Figure 3b**).

As part of the physical examination, the evaluation of possible cervical adenopathies is mandatory; however, locoregional lymph node involvement in these patients is very unusual [11].

### **Figure 3.**

*A 27-year-old male patient with osteosarcoma of the left mandible. (a) Patient on first consult and (b) same patient 3 weeks later.*
