Keywords: Immunohistochemistry; multiple primary tumors; occult breast cancer
Multiple primary tumors (MPTs) are defined as the
occurrence of two or more unrelated tumors that originated
from different organ sites at the same or different
times.[
The aim of the present study was to report an extremely
rare case of simultaneous OBC and rectum
cancer and to demonstrate our diagnostic approach
and treatment procedure. We also emphasized the
importance of immunohistochemical examination
(IHC). This retrospective study includes only the patient"s
medical record and related images. Ethical approval
was not thought to be necessary because the
entire clinical course of the case was completely within
the usual medical care. Written informed consent was
obtained from the patient on each occasion of diagnostic
examinations and therapeutic procedures and also
for the publication of this case report.
She underwent positron emission tomography/
computed tomography (CT). A mass was displayed
in her left axilla approximately 55×70 mm in size with
a high uptake of 18fluoro-2-deoxy-d-glucose 8 (FDG)
with a standardized uptake value (SUV) of 16.69 and a
high uptake of FDG with an SUV of 20.86 in the distal
region of the rectum (Figs.
The contrast-enhanced magnetic resonance imaging
(MRI) of the breast showed that in the left axillary
region, a limited diffusion mass with an intact appearance
of 7×11 cm irregularly shaped cystic necrotic
area was observed. Specifically, no mass or non-mass
enhancement was seen in the breast parenchyma (Fig.
In March 2017, colonoscopy was performed, and an ulcerative, vegetative, 3?4 cm in size lesion was seen in the distal part of the rectum. Biopsy was obtained, and result was reported as adenocarcinoma of the rectum. Based on all the above findings, the outcomes of the patient were discussed in our hospital"s oncology board, and the diagnosis was made as OBC with axillary metastatic carcinoma and synchronous rectum cancer. Radiotherapy (RT) was recommended because she was considered inoperable due to cardiovascular problems. Conformal RT was performed to the left breast, supraclavicular fossa, and axillary level I, II, and III regions with a total dose of 50 Gy with an additional total of 16 Gy boost to mass. During breast RT, the patient complained about rectal bleeding. Palliative RT was planned to the rectum to stop bleeding and applied with a daily fraction dose of 300 cGy to a total dose of 30 Gy. In the follow-up period, axillary mass nearly disappeared in 2 months, and she also had no complaints about rectal bleeding. After 3 months, the patient reported shortness of breath. Clinical examination and thorax CT showed that pulmonary edema occurred due to congestive heart failure, which was the reason of the patient"s death.
The National Comprehensive Cancer Network
guidelines recommend MRI to identify occult breast
lesions not identified by clinical examination or mammography.
MRI showed high sensitivity (ranging from
94% to 100%) for the detection of OBC.[
Olson et al. compared the ability of MRI with traditional
imaging methods for the diagnosis of OBC
in 40 patients and found that MRI accurately locates
the primary foci in resected specimens after breast
surgery in 21 (95%) out of 22 suspected cases. Of the
12 cases with negative MRI results, five underwent
breast surgery, but no primary lesion was detected in
four (80%) cases.[
Owing to unknown clinical symptoms, OBC is usually
detected later than other breast cancers. The diagnosis
is usually made in later stages, and the tumor size
is generally greater.[
Axillary lymph node dissection (ALND) or RT is
the treatment of choice in OBC with axillary metastasis;
comparison of both approaches pointed to prognosis
after ALND is better than RT.[
The optimal treatment of the ipsilateral breast is
controversial. Options include mastectomy, breastconserving
treatment using whole breast radiotherapy, and observation alone.[
The survival rates of patients with OBC compared
with patient's with detectable tumors have been investigated
in many studies. Rosen et al. declared that a
group of patients with OBC has better outcomes than
anatomic stage II?III with clinically apparent breast
cancer although not statistically significant.[
Merson et al. reported that the 5- and 10-year survival
rates among patients with OBC are 76.6% and
58.3%, respectively. Subgroup analysis showed the
number of involved lymph nodes associated with the
prognosis and no difference in survival rates of women
who had mastectomy and who underwent RT.[
In 1973, Browson et al. referred to tumors diagnosed
at the same time or within 6 months as synchronous
primary tumors and metachronous tumors diagnosed
after 6 months depending on appearance time.
The incidence of MPTs is being frequently reported
owing to new diagnostic techniques and longer survival
rates of patients with cancer. The incidence of
MPTs varies between 2.4% and 8% up to 17% in a cancer
population within 20 years of follow-up.[
In fact, there are responsible mechanisms, but the
exact cause of MPTs has not been fully explained. Genetic
susceptibility, the immune system of patients, and
chemotherapy and RT used in the treatment of tumors
are among the most common factors of MPTs.[
Informed consent: Written informed consent was obtained
from the patient for the publication of the case report and the
accompanying images.
Peer-review: Externally peer-reviewed.
Conflict of Interest: The authors declare that they have no
conflict of interest.
Authorship contributions: Concept - Ö.A., L.S.; Design -
Ö.A., L.S.; Supervision - Ö.A., L.S., A.Y.Z.; Materials - Ö.A.,
B.K.O.; Data collection &/or processing - Ö.A.B.K.O.; Analysis and/or interpretation - Ö.A., A.Y.Z.; Literature search
- Ö.A., L.S., B.K.O.; Writing - Ö.A.; Critical review - Ö.A.,
L.S., A.Y.Z.