Tumor Board Presentation- Appendiceal Mucinous Neoplasm

1. Tumor Board Conference
By: Voltaire L. Alojado, MD
February 14, 2024

2. Objectives
1. To discuss a case who presented with gradual increase of abdominal
mass
2. To enumerate di
ff
erentials on patients with gradual increase of abdominal
mass
3. To discuss about appendiceal mucinous neoplasm
4. To enumerate the clinical presentation, work-up and options for patients
with appendiceal mucinous neoplasm
5. To discuss an algorithm on patients with appendiceal mucinous neoplasm

3. General Data
• GE
• 70/M
• Purok Agila Taytayan, Bogo City, Cebu
• Filipino
• Christian

4. Chief Complaint
• Abdominal Distention

5. HPI
• 3 mos PTA, noted gradual enlargement of the abdomen. (+) weight loss,
(+) early satiety, (+) change in stool pattern, (-) vomiting, (-) melena/
hematochezia. No consult was done.
• 1 mos PTA, noted increase in abdominal girth. Hence consult was done to
a gastroenterologist, an a colonoscopy on an OPD basis. Patient was then
advised for CT Scan, which the patient complied a week after.
• Patient was then advised for admission under the gastro service co-
managed with a colorectal surgeon for operation. Hence the patient was
admitted.

6. PMH
• (+) DM2- poor compliance; unrecalled medication
• (-) HPN/BA
• (-) previous hospitalization/surgeries
• (-) maintenance medications

7. FH
• (+) HPN- maternal
• (+) DM- maternal
• (-) FH of malignancy

8. PS
• Smoker- 20 yrs old (5 packs/day for 10 years)l stopped at age 30 yrs old
• (-) allergies

9. PE
• Gen: awake, coherent, not in respiratory distress, oriented to time place and person, GCS 15
• VS:
• 120/90mmHg, 80bpm, 20cpm, 98% O2 sat, Temp 36.5C
• Ht- 5’1”; Wt- 48.8kgs; BMI- 20.3kg/m2 (normal)
• Skin: Senile turgor
• Abd: Distended, (-) previous skin incision, NABS, (-), palpable mass, approx 20x30cm,
entire abdomen, movable, non tender, regular in shape
• DRE: (-) external hemorrhoids, tight sphincter tone, (-) masses/nodules, no blood on
examining
fi
nger

10. Working Impression
• Intraabominal Mass t/c Mesenteric Cyst r/o Malignancy

11. Differentials

12. DDX Rule-In Rule-Out
GIST Intra-abominal mass
Irregular in shape
Early satiety
Weight loss
EGD/Colonoscopy
CT Scan WA w/ Contrast
Biopsy
Tumor Markers (CD117)
Lymphoma Weight loss
Palpable mass in the abdomen
Early satiety
(-) B symptoms:
- High fever
- Drenching night sweats
(-) LAD
(-) hx of bruising/bleeding
(-) repeated infections
EGD/Colonoscopy
CT Scan WA w/ Contrast
Biopsy
IHC Staining (CD3/CD5/CD10/CD20/CD23/
BCL1/BCL2/BCL6/MIB/Ki67)
Colon Cancer Weight loss
Palpable mass in the abdomen
Change in stool pattern
Hx of smoking
(-) easy fatiguability
(-) melena/hematochezia
EGD/Colonoscopy
CT Scan WA w/ Contrast
Biopsy
Tumor Markers (CEA)

13. Work-Up

14. Laboratory Test Feb 2, 2024 Feb 5, 2024 Feb 6, 2024 Feb 8, 2024
CBC
WBC 7.69 10.94 13.12
HGB 12.2 12.3 11
HCT 38.2 37.7 33.4
PLT 221 170 166
Blood Type “B” Rh Positive
HBsAg Nonreactive
Na 141
K 3.8 4.7
Cl 106
Crea 1.3 1.1
Albumin 3.8
aPTT 34.6
PT 10.6
% Activity 96.7
INR 0.88
RAT Negative
Laboratories

15. Chest X-Ray PA View (2/2/24)
• Clear lungs
• Top-normal cardiac size
• Thoracic spondylosis

16. IMAGING
CONTRAST CT OF THE WHOLE ABDOMEN
(HI PRECISION DIAGNOSTIC 1-19-2024)

17. (a)Axial (b) Sagittal, (c) Coronal
view : Lobulated fluid density
mass lesion (*) in the abdominal
region measuring 10.6 x 25.4 x
26.5 cm. Visible thin enhancing
septations (thin arrow) and foci
of calcifications (fat arrow).
Portovenous Phase
(PVP)
a
*
c
*
b
*

20. Possible questions
• Is the appendix visible? – The appendix cannot be visualized due to the mass
effect of the lesion.
• By imaging is it malignant? – No. There is no visceral organ scalloping that could
raise a suspicion of malignancy.
• Is the size of the lesion not malignant looking? – No. Because mucinous neoplasm
tend to grow large and would only cause symptoms due to mass effect.
• Is pseudomyxoma peritonei considered? – The imaging manifestations of PMP
included mucinous ascites, peritoneal soft-tissue implants, omental caking which
is not present radiographically.

21. Colonoscopy 1/8/24
• Anus/Rectum:
• Internal hemorrhoids
• Sigmoid:
• Superficial colitis, severe redundancy w/ no
intraluminal pathology
• Descending:
• Severe redundancy w/ no intraluminal pathology
• Transverse:
• Severe redundancy w/ no intraluminal
pathology, scope only advanced a total of 1 cm
before severe luminal narrowing precludes
advancement, abundant vegetable matter noted
• Post-endoscopy Diagnosis:
• Left-sided colitis, severe luminal narrowing and
redundancy, t/c external compression, internal
hemorrhoids

22. Perioperative

23. Pre-Operative
• Preop Dx:
• Intrabominal Mass t/c Mesenteric Cyst r/o Malignancy
• Procedure Performed:
• Exploratory Laparotomy, Adhesiolysis, Partial Excision of Intra-
abdominal Mass, Appendectomy, JP Drain
• Postop Dx:
• Appendiceal Mucinous Neoplasm

24. Intra-Operative
• Date of Operation: February 5, 2024
• Type of Anesthesia: General Anesthesia w/ Spinal Epidural
• Time Started: 4:45pm
• Time Ended: 10:33pm
• Operative Time: 5 hours and 38 mins
• Estimated Blood Loss: 400cc
• Preoperative Medications:
1. Cefoxitin 2 grams IVTT 1 hr prior to OR
2. Omeprazole 40 mg IVTT OD once on NPO

25. Intra-Operative
Liver
Part of the cyst
adherent w/ the liver
Part of the cyst
adherent w/
diaphragm
Stomach
Asc Colon
Trans Colon
Small Intestines

26. Intra-Operative
APPENDIX Cystic Mass
Filled w/ Mucin

27. Histopathologic Report

28. Histopathologic Report 2/5/24
• “Low-Grade Appendiceal Mucinous Neoplasm”
• Tumor Size: 20cm in greatest dimension
• Histologic Grade: I
• Tumor Extent: Acellular mucin invades visceral peritoneum (serosa)
• Lyphatic and/or vascular invasion: not identi
fi
ed
• Margin status: Low-Grade Dysplasia present at proximal margin
• pTNM Classi
fi
cation (AJCC 9th Version): pT4a

29. S24-305

36. FINAL DIAGNOSIS
LOW-GRADE APPENDICEAL MUCINOUS
NEOPLASM.
*TUMOR SIZE: 20 CENTIMETERS IN GREATEST DIMENSION.
*HISTOLOGIC GRADE: GRADE 1.
*TUMOR EXTENT: ACELLULAR MUCIN INVADES VISCERAL PERITONEUM
(SEROSA).
*LYMPHATIC AND/OR VASCULAR INVASION: NOT IDENTIFIED.
*MARGIN STATUS: LOW-GRADE DYSPLASIA PRESENT AT PROXIMAL MARGIN.
*pTNM CLASSIFICATION (AJCC 9th VERSION): pT4a.

37. Case Discussion
By: Voltaire L. Alojado, MD
February 14, 2024

38. Introduction
• Peritoneal surface malignancies represent a heterogenous group of intraperitoneal
malignancies arising from the lining of the abdominal and pelvic cavity
• They include primary malignancies of the peritoneum such as:
1. Di
ff
use Malignant Peritoneal Mesothelioma
2. Peritoneal Serous Papillary Carcinoma
3. Desmoplastic Small Round Cell Tumors
4. Metastases from other primary tumors typically involving the:
• Colon, stomach and ovaries

39. Introduction
• Cytoreductive surgery (CRS) and Hyperthermic Intraperitoneal
Chemotherapy (HIPEC) have evolved over the past decade to provide a
therapeutic advantage to patients who otherwise have limited options
beyond systemic chemoradiation for locoregional control of palliation

40. Appendiceal Neoplasm

41. Epidemiology and Classi
fi
cation
• 0.12 cases per 100,000
• Commonly diagnosed incidentally on pathology (1-2% of appendectomy
specimens)
• Tumors can be mucinous or non-mucinous histology and may contain
signet ring component
• Very aggressive, 60% w/ distant mets at the time of diagnosis
• Pseudomyxoma Peritonei (PMP)- characterized by mucinous ascites
and peritoneal implants

42. Epidemiology and Classi
fi
cation
• World Health Organization (WHO 2010)
• 3 Categories:
1. Mucinous Adenoma
2. Low-Grade Appendiceal Mucinous Neoplasm (LAMN)
3. Mucinous Adenocarcinoma

43. Epidemiology and Classi
fi
cation
• Peritoneal Surface Oncology Group International Consensus 2016
• Developed a classi
fi
cation system to describe both the primary lesion
and peritoneal disease
1. Noncarcinoid Epithelial Neoplasm of the Appendix itself
2. High-Grade Appendiceal Mucinous Neoplasm (HAMN)
• For lesions w/ low-grade architectural features of Low-Grade
Appendiceal Mucinous Neoplasm but with high-grade cytologic
features

45. Clinical Manifestation
• Common Presentation:
1. Increasing abdominal girth
2. Weight loss
3. Fatigue
4. Bloating
5. Constipation
6. Pain

46. Clinical Manifestation
• Not uncommonly the diagnosis is made on presentation w/
acute appendicitis, obstruction of the appendiceal lumen by
malignant cells, which may lead to in
fl
ammation and infection
of the appendix
• Mucinous tumors may present w/ cystic dilation of the
appendix, which could also mimic symptoms of appendicitis or
be found incidentally on imaging for a di
ff
erent etiology

47. Clinical Manifestation
• Men- may also present w/ hernia
• Women- w/ bulky pelvic mass
• Anorexia, Early Satiety, and Massive Ascites- are also
common manifestations, and in some ways likely underestimate
the true incidence of the disease given the late clincal
presentation of these neoplasms

48. Preoperative Work-up
• CT of the chest/abdomen/pelvis
• Routine CBC, basic metabolic panel, and nutritional markers
• Serum tumor markers:
• CEA, CA 19-9, CA 125, and Chromogranin A
• Preoperative colonoscopy- to evaluate synchronous or metachronous
colonic lesions
• Diagnostic laparoscopy- useful in determining eligibility for cytoreductive
surgery in addition to obtaining histologic assessment (guide treatment plans)

49. Patient Selections
• Patient selection is extremely important in deciding who will most bene
fi
t from
CRS and HIPEC and to avoid signi
fi
cant morbidity and mortality in patients who are
not expected to bene
fi
t
• Surgeons should consider the
ff
:
1. Extent of disease
2. Tumor biology
3. Physiologic age
4. Co-morbidities
5. ECOG/WHO functional and fraility status

50. Patient Selections
• Scoring system such as the Periteonal Disease Severity Score
(PDSC), which was devised to stage patients w/ colon cancer
based on the
ff
:
1. Clinical symptoms
2. Extent of carcinomatosis based on radigraphic evidence
3. Tumor histopathology

51. Patient Selections
• LAMN (grade I)- CRS+HIPEC is the treatment of choice if
complete cytoreduction can be achieved
• Adenocarcinoma and Peritoneal metastasis
• Are likely to have to complete cytoreduction and overall have
poor survival than those w/ LAMN

52. Patient Selections
• Not all LAMNs or well-di
ff
erentiated mucinous
adenocarcinomas require a right hemicolectomy
• Unless there is a clear involvement of the colon serosa, which
would necessitate colectomy

53. Patient Selections
• American College of Surgeons’ NSQIP surgical risk
calculator
• May also be used to estimate perioperative risk, especially in
patients w/ signi
fi
cant cardiopulmonary co-morbidities not
captured by the (PDSC)

54. Patient Selections
• Multidisciplinary team w/ considerations given to probability of
extensive organ resection, morbidity, quality of life, and
recurrence risk

59. • Please take picture of
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link in the chat box for
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60. End of Presentation