Multiple rapidly growing desmoid tumors that were difficult to distinguish from recurrence of rectal cancer
Nakanishi et al. World Journal of Surgical Oncology
Multiple rapidly growing desmoid tumors that were difficult to distinguish from recurrence of rectal cancer
Koki Nakanishi 0
Dai Shida 0
Shunsuke Tsukamoto 0
Hiroki Ochiai 0
Junichi Mazaki 0
Hirokazu Taniguchi 1
Yukihide Kanemitsu 0
0 Department of Colorectal Surgery, National Cancer Center Hospital , 5-1-1, Tsukiji, Chuo-ku, Tokyo 1040045 , Japan
1 Pathology and Clinical Laboratory Division, National Cancer Center Hospital , 5-1-1, Tsukiji, Chuo-ku, Tokyo 1040045 , Japan
Background: Intra-abdominal desmoid tumors are usually slow growing and solitary, but multifocal desmoid tumors develop on rare occasions. Diagnosing desmoid tumors before histological examination of a surgical biopsy is often difficult. In particular, if a patient has a prior history of malignancy, it may be difficult to differentiate between these lesions and disease recurrence or metastasis. Case presentation: We present a rare case of multiple rapidly growing intra-abdominal desmoid tumors after surgical trauma, without familial adenomatous polyposis. A 51-year-old male underwent abdominal perineal resection with lateral lymph node dissection after neoadjuvant chemotherapy for lower rectal cancer. Follow-up computed tomography (CT), performed 6 months after primary surgery, showed a 20-mm solitary mass in the pelvic mesentery. Another CT scan, performed 3 months later, revealed that the mass had grown to 35 mm in size and that two new masses had formed. Based on imaging studies and his medical history, it was difficult to distinguish the desmoid tumors from recurrence of rectal cancer. Curative resection was chosen for therapeutic diagnosis. The pathological diagnosis was multiple mesenteric desmoid tumors. Conclusions: Desmoid tumors should not be excluded as a differential diagnosis for intra-abdominal masses after intra-abdominal surgery, even in cases of rapidly growing multiple masses.
Desmoid tumors; Mesenteric fibromatosis; Rectal cancer; Intra-abdominal; Cancer recurrence
Background
A desmoid tumor is a monoclonal fibroblastic
proliferation that arises from deep soft tissue and is characterized
by infiltrative growth and a tendency toward local
recurrence but an inability to metastasize [
1
]. Desmoid
tumors are usually solitary, but multifocal desmoid tumors
develop on rare occasions, comprise less than 5% of all
desmoid tumor cases, and typically occur at the
extremities in premenopausal women [
2
]. Intra-abdominal
desmoid tumors can be sporadic or occur in association with
familial adenomatous polyposis (FAP) [
3
]. Diagnosing
desmoid tumors before histological examination of a surgical
biopsy is often difficult. In particular, if a patient has a
prior history of malignancy, it may be difficult to
differentiate between these lesions and disease recurrence or
metastasis [
4–6
]. Here we report a case of multiple rapidly
growing intra-abdominal desmoid tumors which appeared
6 months postoperatively, which could not be
differentiated from recurrence of rectal cancer.
Case presentation
A 51-year-old male, who had received neoadjuvant
chemotherapy (nine courses of oxaliplatin/5-fluorouracil/
leucovorin (mFOLFOX6)) for locally advanced lower
rectal cancer, underwent abdominal perineal resection with
lateral lymph node dissection. He had no remarkable
medical or medication history, except for diabetes. He had
no family history of FAP. His postoperative recovery was
uneventful, with the exception of intrapelvic fluid
collection which was drained percutaneously. Histological
examination of the tumor revealed a well- to moderately
differentiated adenocarcinoma (stage II (pT3N0M0)
according to the 7th TNM classification of the International
Union Against Cancer) [
7
]. He was scheduled for regular
cancer surveillance after surgery with three monthly
serum carcinoembryonic antigen (CEA) and serum
carbohydrate antigen 19-9 (CA19-9) measurements and six
monthly contrast-enhanced computed tomography (CT)
evaluations of the thorax, abdomen, and pelvis. Six
months postoperatively, CT revealed a solitary mass
(lesion 1) in the pelvic mesentery, 20 mm in size (Fig. 1).
Serum CEA and CA19-9 levels were normal. Recurrence
of rectal cancer was suspected, but could not be
confirmed, and thus, close follow-up was chosen. Another
CT, performed 3 months later, showed that the mass had
grown to be 35 × 30 mm in size (lesion 1), with two new
masses measuring 20 × 15 mm (lesion 2) and 15 × 10 mm
(lesion 3) forming at the mesentery of the small bowel
(Fig. 2). Pelvic magnetic resonance imaging (MRI) on
T2weighted images revealed that the central part of the
tumor was hypointense and the peripheral part was
hyperintense, which was gradually enhanced with gadolinium
contrast MRI (Fig. 3). Positron emission tomography
(PET)-CT showed increased fluorodeoxyglucose (FDG)
uptake in all tumors (max standardized uptake value:
SUV = 3.31 (lesion 1), 2.55 (lesion 2), and 2.22 (lesion 3))
(Fig. 4) (...truncated)