Management of unresectable solid papillary cystic tumor of the pancreas. A case report and literature review

Journal of Pediatric Surgery (2010) 45, E1–E6

www.elsevier.com/locate/jpedsurg

Management of unresectable solid papillary cystic tumor of the pancreas. A case report and literature review Pietro Soloni a , Giovanni Cecchetto b , Patrizia Dall'Igna b , Modesto Carli a , Tiziana Toffolutti c , Gianni Bisogno a,⁎ a

Division of Hematology/Oncology, Department of Pediatrics, University Hospital of Padova, 35128 Padova, Italy Division of Pediatric Surgery, Department of Pediatrics, University Hospital of Padova, 35128 Padova, Italy c Section of Pediatric Radiology, Institute of Radiology, University Hospital of Padova, 35128 Padova, Italy b

Received 14 October 2009; revised 9 February 2010; accepted 11 February 2010

Key words: Solid pseudopapillary tumor; Papillary cystic neoplasm; Pancreas; Cystic and solid tumor; Frantz tumor

Abstract Pancreatic solid papillary cystic tumor is a rare neoplasm with an excellent prognosis if surgical excision is complete. We report on a case and review 47 more cases extracted from the published literature to assess the treatment options when solid papillary cystic tumor is considered unresectable. Chemotherapy and radiotherapy were beneficial in a limited number of patients, but therapeutic decisions must be made bearing in mind that patients may be long-term survivors without any treatment because of the tumor's slow growth. © 2010 Elsevier Inc. All rights reserved.

Solid papillary cystic tumor (SPT) of the pancreas is an uncommon epithelial tumor accounting for 2% to 3% of all pancreatic tumors occurring at any age. It typically affects young women in their second or third decade of life, whereas it is exceptional in children [1,2]. It is characterized by a solid cystic appearance, often surrounded by a fibrous pseudocapsule. Microscopically, it consists of a combination of solid, pseudopapillary, and hemorrhagic pseudocystic structures; on immunohistochemical investigation, it expresses epithelial, mesenchymal, and endocrine markers [3,4]. Solid papillary cystic tumor appears to be an indolent neoplasm with a low, but often unpredictable, malignant potential. Metastases, especially in the liver, have been

⁎ Corresponding author. Tel.: +39 049 8211481; fax: +39 049 8213510. E-mail address: [email protected] (G. Bisogno). 0022-3468/$ – see front matter © 2010 Elsevier Inc. All rights reserved. doi:10.1016/j.jpedsurg.2010.02.045

described in up to 20% of patients [4] and can be seen at diagnosis or appear after long disease-free periods [1]. The prognosis is excellent when surgical excision is complete, although the treatment for patients with inoperable or relapsing tumors is less clear. To help clarify the most suitable management for such patients, we reviewed the literature and discuss a case that we have recently treated.

1. Case report An 11-year-old girl with a previously unremarkable medical history underwent abdominal US after a mild abdominal trauma. A pancreatic lesion was discovered, and a computed tomographic (CT) scan confirmed the presence of a large mass arising from the pancreatic body. No evidence of distant metastases or increase in tumor markers (α-fetoprotein, β-subunit of human chorionic gonadotropin,

E2 carcinoembryonic antigen, carbohydrate antigen-19.9, α1antitrypsin) was evident. The child underwent surgery, and the mass was resected completely; but tumor spillage occurred during the procedure. Histopathologic examination identified an SPT of the pancreas. No further therapy was administered. Six years later, the girl was asymptomatic' but a follow-up abdominal CT revealed a large pancreatic mass (10 × 7 × 4 cm) extending down to the inferior pole of the right kidney. Two pelvic masses (both 3 cm in diameter) and 4 small hepatic lesions (maximum diameter of 1 cm) were also evident. Complete tumor resection was deemed unfeasible. A biopsy was performed and confirmed the recurrent SPT. Chemotherapy with a biweekly administration of gemcitabine (1000 mg/m2 per cycle) and oxaliplatin (100 mg/m2 per cycle) was initiated; but no tumor reduction was evident after 4 and 8 cycles, respectively. The therapy was changed and, after 2 cycles of 5fluorouracil (5-FU) 800 mg/m2 in a continuous 120-hour infusion and cisplatin (CDDP) 60 mg/m2 as a single administration, a CT scan showed a tumor shrinkage, with the disappearance of 3 of the liver metastases and a reduction of both the pancreatic (to 9 × 5.5 × 4 cm) and the pelvic lesions (to 2.5 cm) (Fig. 1). Unfortunately, no further tumor reduction was achieved after 3 more cycles; and the tumor remained inoperable owing to its local extension and mesenteric vessel infiltration.

P. Soloni et al. Radiotherapy was refused by the family, and the treatment was stopped. The girl is still in good condition 2 years since her relapse, but with radiological evidence of slow tumor progression.

2. Literature review We searched the English literature on solid pseudopapillary tumors of the pancreas from 1980 to 2009. Only articles describing the treatment of patients of all ages with SPT that were unresectable at diagnosis or on recurrence were considered (independently by at least 2 authors) for inclusion in the review. All references quoted in the selected articles or reviews on SPT were also analyzed, and the pertinent studies were added to our review. A specific database containing the characteristics and treatment of patients with unresectable SPT was created for the purpose of this analysis.

3. Results Including the present report, we identified 42 articles describing 52 patients with unresectable SPT. One article and

Fig. 1 Computed tomographic scan at relapse shows a solid lesion arising from the pancreatic area, involving the superior mesenteric artery (A), and 2 of the 4 liver metastases in the 6° and 7°liver segments (B). After chemotherapy (2 cycles of CDDP + 5-FU), a regression of the pancreatic lesion (C) and the disappearance of liver lesions (D) are evident.

Unresectable solid papillary cystic tumor of the pancreas Table 1

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Clinical characteristics and treatment of 48 patients with unresectable SPT

No Disease

Age/sex Treatment

Treatment response

Outcome Ref (years after diagnosis)

1 2 3 4 5 6 7

Relapse Relapse Diagnosis Diagnosis Diagnosis Relapse Diagnosis

12/F 12/F 18/F 39/F 47/F 60/F 32/F

AWD (6) AWD (9) AWD (3) AWD (4) DOD (3.9) DOD (6) AWD (3.4)

[5] [6] [33] [26] [7] [7] [35]

8 9

Diagnosis 20/F Diagnosis 15/F

– – TR MD TR – Mts reduction after RT; NR to IFN SD TR (80%) after 4 cycles

AWD (2)

[41] [22]

10 11 12 13 14 15 16 17 18 19

Relapse Diagnosis Diagnosis Relapse Relapse Diagnosis Diagnosis Diagnosis Diagnosis Diagnosis

– TR MD MD MD – – NR TR (50%) PM

DOD (10.9) AWD (10) DOD (1.2) DOC (1.6) AWD (6) AWD (1) AWD (13) AWD (12) NED (1) DOD (15)

[8] [25] [30] [42] [1] [9] [9] [42] [23] [27]

– – NR

DOD (0.5) DOD (1.3) DOD (0.8 after relapse) NED (MD)

[11] [11] [36]

AWD (1.5) NED (MD)

[37] [31]

DOD (0.2) DOD (0.8) DOD (8) DOD (7.7) DOD (3)

[12] [32] [43] [10] [10]

36/F 38/F 15/M 34/F 12/F MD MD 20/F 18/F 53/F

20 Diagnosis 33/F 21 Relapse 45/F 22 Relapse 13/F 23 Diagnosis 23/F 24 Relapse 20/F 25 Diagnosis MD/F 26 27 28 29 30

Relapse Relapse Relapse Dgn Relapse

34/F MD 45/M MD MD

31 Diagnosis 33/F 32 33 34 35

Relapse Diagnosis Relapse Diagnosis

Tamoxifen CDDP + 5-FU followed by surgery (Whipple procedure) None 5-FU + epirubicin + mitomycin-C Palliative RT + CT (MD) TAE IFO + CDDP + VP-16; IFN None None Tamoxifene CDDP + gemcit followed by distal pancreatectomy Doxo + strepto +5-FU; somatostatin; IFN; CDDP + topotecan; thalidomide None None RFA (liver Mts)

RT (50.4 Gy) + 5-FU; gemcit; followed by surgery SD after 5-FU + RT; (Whipple procedure) TR after gemcit RFA; TAE NR CT (MD) followed by subtotal MD pancreatectomy + splenectomy None / Gemcit MD Imatinib NR None / VP-16 + CDDP + cyclophosphamide + TR doxo + VCR; RT (50.4 Gy) TR

36 Diagnosis 14/F

RFA None RFA; TAE with doxo CDDP + IFO + VP-16 + VCR; resection (mass) + RFA (liver Mts) Liver transplantation

37 38 39 40 41 42 43 44

None None None 5-FU + CDDP None None None Gemcit, irinotecan, OXP, 5-FU, capecitabine

Relapse Diagnosis Relapse Relapse Relapse Diagnosis Diagnosis Relapse

46/F 13/F 32/M 14/F

None None RT (40 Gy) 5-FU + doxo + mitomycin-C RT (75 Gy) + CT (MD) None RT (liver, 30 Gy; pancreas, 40 Gy), IFN

57/F 68/F MD MD MD 18/F 42/F 49/F

AWD (1.5 after relapse) MD AWD (30) AWD (0.7) NR DOD (2.2) TR after 4 cycles. All but 1 NED (3) liver Mts disappeared. – NED (2.6 after relapse) – AWD (8) – AWD (5) – DOD (2) MD AWD (3.2) – AWD (20) Spontaneous TR AWD (10) – AWD (0.2) PM to all treatment but SD AWD (8) after capecitabine

[24]

[34] [38] [15] [39] [28] [44] [13] [14] [20] [20] [16] [17] [19] [29]

(continued on next page)

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P. Soloni et al.

Table 1 (continued) No Disease

Age/sex Treatment

Treatment response

Outcome Ref (years after diagnosis)

45 46 47 48

MD MD MD 17/F

– MD – SD after OXP + gemcit; TR after CDDP + 5-FU

DOD (0.9) AWD (8.8) DOD (0.5) AWD (2.2)

Diagnosis Relapse Relapse Relapse

None Gemcit None OXP + gemcit; CDDP + 5-FU

[18] [18] [21] a

Doxo indicates doxorubicin; gemcit, gemcitabine; strepto, streptozocin; IFN, interferon; IFO, ifosfamide; VP-16, etoposide; VCR, vincristine; OXP, oxaliplatin; AWD, alive with disease; RT, radiotherapy; CT, chemotherapy; MD, missing data; TR, tumor reduction; DOD, died of disease; NR, no response; Mts, metastases; SD, stable disease; NED, no evidence of disease; TAE, transcatheter arterial embolization; RFA, radiofrequency ablation; PM, progression of disease. a This report.

4 patients were ruled out because the treatment was not described, so 48 patients were considered for this analysis (47 from the literature and the case we have described). Tumor resection was considered unfeasible at diagnosis (in 25 cases) or recurrence (23) owing to extensive metastatic spread or invasion of surrounding organs, with or without vascular involvement. The patients' characteristics and treatment are described in Table 1. Nineteen patients (9 at diagnosis and 10 at relapse) were given no specific treatment after the surgical option had been rejected [6-21]. Nine patients died from 0.2 to 10.9 years after their diagnosis (median, 1.33 years), whereas 10 are alive with disease 0.3 to 20 years since their diagnosis (median, 5.5 years). Surgery was recommended but refused in 2 cases; in one of these, a spontaneous reduction in tumor volume was apparent 10 years after its diagnosis [17]. Different chemotherapeutic combinations were administered to 17 patients, 10 at diagnosis and 7 at relapse [1,7,10,18,20,22-32]. A tumor reduction was described in 8 cases. Cisplatin was used as part of the chemotherapy combination in 8 patients, and 5 of these responded to some degree (although the benefit was only clinical in 1 case, the disease progressed in 1, and there is no mention of the response in 1). A response was reported in 3 of 8 patients treated with 5-FU and in 2 of 6 treated with gemcitabine. After neoadjuvant chemotherapy, 5 patients (4 with advanced local disease or vascular involvement and 1 with metastatic dissemination and vascular involvement) underwent surgery and were all alive with no evidence of disease 1.1 to 4 years since their diagnosis (but the length of followup is missing for 2 cases) [22-24,28,31]. Radiotherapy alone was delivered to 3 patients, and a reduction of the primary or metastatic lesions was reported in all 3. Irradiation was combined with chemotherapy in another 3 patients, and a response was reported in 1 [7,24,30,33-35]. Radiofrequency ablation of liver metastases was used in 5 patients, only 1 of them reportedly alive with no evidence of disease 3 years after its diagnosis [28,36-39]. Transcatheter arterial embolization was used in 3 patients with no apparent benefit, and 1 died of a procedure-related complication

[37,39,40]. Other treatments included: interferon (in 2 patients) [27,35], tamoxifene (2) [41,42], and imatinib (1) [43]; but no response was recorded. One child underwent liver transplantation owing to multiple liver metastases and is alive in complete tumor remission 2 years since the transplant [44]. Overall, 18 patients died and 30 are alive with (24) or without (6) evidence of disease 0.2 to 30 years since their diagnosis (median, 6 years).

4. Discussion Solid papillary cystic tumor is a rare entity, but its frequency seems to be increasing now that its characteristics have been better clarified [15,17,45]. Its clinical behavior and pathologic appearance are consistent with a low-grade malignancy, with an excellent prognosis when the tumor is resected completely. The management of these patients is more difficult in cases with metastases or invasion of adjacent structures. After initial resection, relapses may occur and may be so extensive as to preclude further surgery. A recent literature review suggested that nearly 20% of cases presented with metastases, mainly to the liver and spleen, and/or with portal vein invasion; in the same series, 6.6% of the 467 patients suffered a relapse [4]. Although surgery of the primary and metastatic or recurrent lesions is recommended by most authors to enable long-term survival [4], the case we have described is one of a limited set of patients with unresectable lesions. The management of such cases has not been homogeneous; and the use of chemotherapy and radiotherapy has been sporadic, with controversial results [1,7,10,18,20,22-35]. Unresectable SPT at diagnosis or at relapse poses the same management problems. In addition, the patients in the relapsed group received only surgery as first-line treatment, excluding any possible influence on the effects of chemotherapy or radiotherapy administered after relapse. Consequently, we decided to include these 2 groups of patients in the same analysis.

Unresectable solid papillary cystic tumor of the pancreas Judging from our literature review, 40% of patients with unresectable SPT did not receive any specific treatment after their diagnosis. In the absence of substantial data on the efficacy of chemotherapy or radiotherapy, this approach was motivated in various ways. In some cases, no further treatment was considered feasible by the clinician or family because of the patient's poor conditions and/or the extent of the tumor (this group of patients died shortly after their diagnosis or relapse). Sometimes, the decision to avoid giving any treatment may have been based on the slow progression of SPT (a substantial proportion of these untreated patients survived for up to 20 years). Surprisingly, a case of spontaneous tumor shrinkage has also been reported [17]. It is not clear whether SPT responds to chemotherapy. In vitro tests have suggested that SPT may be sensitive to gemcitabine, epirubicin, docetaxel, paclitaxel, and mitomycin C, whereas it is reportedly scarcely sensitive to CDDP and 5-FU [46]. Our experience and the literature review produced somewhat different results; in fact, the most often used drugs were CDDP, 5-FU, and gemcitabine. The CDDPbased regimens scored best for tumor response. The case we describe supports an effect of CDDP against SPT and shows that CDDP cannot be substituted by analogues such as oxaliplatin. Our review found that 5 of the 17 patients treated with neoadjuvant chemotherapy subsequently underwent tumor resection. Radiotherapy was used in a few cases, and tumor shrinkage was reported, but none of these patients subsequently underwent surgery. In conclusion, our experience and the literature fail to provide clear indications for the treatment of patients with unresectable SPT. Cisplatin-based chemotherapy may achieve a tumor reduction, probably in association with gemcitabine or 5-FU, and, in our opinion, should be administered when a radical surgery could not be anticipated. This could facilitate surgical resection in a limited number of patients. Radiotherapy did not induce any tumor response substantial enough to make it operable, but it may be considered in association with chemotherapy or for palliative purposes. In considering any of these treatments, it is important to bear in mind that patients may have a good quality of life for many years without any treatment at all, given this tumor's slow growth.

Acknowledgments Partially supported by a grant from the Fondazione Cassa di Risparmio di Padova e Rovigo. This paper is part of the SPeLeS Project (Specializzandi in Pediatria e Letteratura Scientifica), an academic scheme organized by the Department of Pediatrics in Padova to improve resident pediatricians' expertise in analyzing teaching cases and writing scientific reports.

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