Jaw Pain as a First Presentation in the Diagnosis of BreastCancer

Introduction

The oral cavity is rare site for metastatic dissemination, accounting for only 1% of allmalignancies in the region (1). This involvement isusually diagnosed secondary to malignancy; however, in approximately one-third of casesmetastasis is the first clinical manifestation (1-3). “The most common primary origins include thelung, kidney, liver, and prostate for men and breast, female genital organs, kidney, andcolorectum for women” (4); however, primary site couldbe affected by geographic location (4- 7). In the most of cases, radiographic appearanceincreases the suspicion of malignancy; but pathological changes are not observed in about 5%of the radiographs (3). The most common sites forbreast cancer to metastasize are the bone, lung, liver, lymph nodes, and brain (8).

We encountered with a rare case in which metastasis to mandibular bone was the firstclinical sign in the diagnosis of breast cancer without any radiographic findings,highlighting the importance of clinical manifestation in the oral cavity and incisionalbiopsy and immunohistochemical techniques in the diagnosis.

Case report

A 49-year-old premenopausal woman presented with complaints of pain and tenderness in theleft mandibular region and paresthesia of the lower left lip and chin in Jul 2014. She haddenied any medical, surgical, or significant family history. Her last mammogram wasperformed 6 months ago for screening, which was unremarkable. A CT scan of the head and neckrevealed no significant finding. She was started on a trial of gabapentin, duloxetine, andcarbamazepine for trigeminal neuralgia. In Dec 2014, she was referred to the Department ofMedical Oncology of Imam Hossein Hospital, Shahid Beheshti University of Medical Sciences,Tehran, Iran with complaint of pain and tenderness over the left breast and worsening ofpain and paresthesia the left half of the face that did not respond to any analgesicmedication. Breast examination revealed a 2-cm firm nodule on the left breast. Informedconsent was taken from the patient.

Her pathologic report was consistent with invasive ductal carcinoma (IDC) of two leftbreast mass and axillary lymph node. Immunostaining was positive for ER/PR but negative forHER-2; Ki67 was positive in approximately 40% of cells. A whole body bone scan (WBBS)revealed abnormal isotope accumulation in the left mandible, suggestive of bonyinfiltration. Consequently, CT scan of the head and neck was performed which revealedthickening and sclerosis of the body and ramus of the left hemimandible. Incisional biopsieswere obtained and composed of small needlelike firm tissue with bone consistency measuring 1cm in length and 0.4 cm in width, showing a neoplasm not related to the mandibular region,made up of hyperchromatic nuclei and large eosinophilic cytoplasm cells. The cells weredisposed of in abortive glandular-like structures with significant sclerosis placed betweensegments of bone and into bone marrow spaces. The tumor cells exhibited positiveimmunostaining for CK7, ER/PR, GCDFP-15, and Mammaglobin and negativity for CK20. Thesehistological findings were suggestive of metastatic invasive ductal carcinoma (Fig. 1). Other metastatic workup, including spiral CT scanof the thorax, abdomen, and pelvic area, were normal. She was started ondoxorubicin/cyclophosphamide/5-FU chemotherapyy, and local irradiation of the left mandiblewas performed. The patient underwent radiation therapy over 2 wk, which resulted in reliefof her symptoms and remission of the disease.

Fig. 1

Malignant ducts of breast origin infiltrating jaw bone

Discussion

The oral cavity is uncommon site for metastatic disease reported only approximately 1% ofall oral malignancies (1). The primary tumor isusually known before the oral metastatic lesion appeared in most patients (1- 3). In a study,only 169 cases with the oral metastatic tumor, the first sign was involvement this region(3). The most primary site of metastatic lesions isin diminishing order the breast, lung, kidney, and prostate; although it appears thatgeographic location mainly between east and west may be effect of region involvement (4). The uterus was the most common primary location inwomen (6). Furthermore, the liver and thyroid wasrecognized to be the most common main sites for men and women, respectively (5).

Oral metastatic lesions may occur into mucosal and jawbone, however, the jawbones,especially mandible are more frequent for metastasis than the oral mucosa (4). Swelling, pain and paraesthesia are the commonsymptoms of a metastatic tumor in the jawbones. Mental nerve neuropathy, known as ‘‘numbchin syndrome’’ could be the sign of a metastatic disease in the mandible; however, thesesymptoms could result from trauma, infection or noticeable odontogenic reasons and systemicdiseases such as amyloidosis, sarcoidosis, or as neurological manifestation of anon-metastatic malignancy (9). Therefore, earlydetection of jawbone metastasis is usually difficult. In the early stages, lesions may notcause radiological features (3, 10) and the pathological evaluation of the lesions is mandatory fordiagnosis. In our report, mandibular involvement was first sign of malignancy that thecomputed tomography failed to detect it in early stages.

The most common histopathological types of primary tumors including breast areadenocarcinoma (1, 11). However, ductal carcinoma, such as our case, may be observed in breastinvolvement (11). Likewise, to confirm the primarysite of tumor immunohistochemical techniques is necessary. Breast neoplasm usually presentCK7 but not CK20 (4) and along with positivity forER/PR, GCDFP-15, Mammaglobin could be ruled out other malignancy.

The mechanism of metastatic tumors to the oral cavity is unknown, but a hematogenous spreadfrom a distant region is considered. In the breast cancer, the bone, lung, liver, lymphnodes, and brain are the most common sites for metastasis, but oral cavity involvement isvery rare (1-4,11).

Palliative therapy is primarily management of metastatic breast cancer to the oral cavityand generally includes chemotherapy, hormone therapy and local radiotherapy (12). Oral metastasis carries a poor prognosis for thepatient because it represents advanced disease; however, in this case, primary tumorpresentation can be a solitary mandibular metastasis (10).

Manifestations of malignancy including breast are not always straightforward. Therefore, inthe presence of an ambiguous sign in the oral cavity, such as jaw pain or paresthesia, adifferential diagnosis must include metastatic dissemination, and diagnostic examination ishighly recommended.

Conflict of Interests

The authors declare that there is no Conflict of Interests.