The patient is a 42-year-old male who was diagnosed with an adenocarcinoma located in the sigmoid colon during a...

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The patient is a 42-year-old male who was diagnosed with an adenocarcinoma located in the sigmoid colon during a colonoscopy on [date removed]. The colonoscopy also revealed diverticulosis and one tubular adenoma that was completely removed. Plan as of Dec 12, 2025 = “Recent scans with a mixed response we will continue therapy as per the protocol; C5D22 today: - Cetuximab 500 mg/m2 d1, d15, d29 - Cemiplimab 350 mg on” LABS: Imaging: 10/21/24: CT-scan of chest, abdomen and pelvis: The liver is normal in size. Multiple hypoenhancing liver masses are decreased in size compared to [date removed]. Reference lesions: Segment 4A, 2.1 cm (3/89), previously 2.8 cm. Segment 4B, 0.8 cm (3/112), previously 1.5 cm. Persistent wall thickening of the distal sigmoid colon consistent with the primary CEA Latest Ref Rng 0.0 - 3.3 ng/mL [date removed] 1.4 [date removed] 1.2 [date removed] 1.0 [date removed] 1.2 [date removed] 2.7 [date removed] 4.3 (H) [date removed] 5.8 (H) [date removed] 10.5 (H) [date removed] 18.1 (H) [date removed] 24.2 (H) [date removed] 29.0 (H) Mass General Brigham Patient Gateway - Past Visit Details https://patientgateway.massgeneralbrigham.org/MyChart-PRD/app/visit... 5 of 8 [date removed], 3:18 PM colon mass (3/181). Similar ill-defined soft tissue along the superior left lateral aspect of the thickened distal sigmoid colonic wall, suspicious for tumor extending beyond the bowel wall (3/177). A 2.2 cm soft tissue lesion in the anterior mesorectal fascia is decreased in size (3/200), previously 3.5 cm on [date removed]. Mild persistent nonspecific stranding surrounding the sigmoid colon and rectum. The left upper quadrant peritoneal nodules have decreased in size, with the largest measuring 0.9 cm (3/113), previously 2.0 cm on [date removed]. A 1.4 cm short axis portacaval lymph node is stable (3/105). A borderline-enlarged 0.9 cm porta hepatis lymph node is also stable (3/102). 12/13/24: CT-scan of chest, abdomen and pelvis The liver is normal in size. Multiple hypoenhancing liver masses are stable in size. No new definite hepatic lesions. Portal and hepatic veins are patent. Reference lesions: Segment 4A, 2.1 cm (3/ 86), previously 2.1 cm. Segment 4B, 0.9 cm (3/111), previously 0.8 cm. Persistent wall thickening of the distal sigmoid colon consistent with the primary colon mass (3/179). Similar ill-defined soft tissue along the superior left lateral aspect of the thickened distal sigmoid colonic wall, suspicious for tumor extending beyond the bowel wall (3/177). A 2.5 cm soft tissue lesion in the anterior mesorectal fascia is increased in size (3/199), previously 2.2 cm. Mild persistent nonspecific stranding surrounding the sigmoid colon and rectum. The left upper quadrant peritoneal nodules are no longer clearly delineated. A 1.3 cm short axis portacaval lymph node is stable (3/105). A borderline-enlarged 0.9 cm porta hepatis lymph node is also stable (3/101). 2/6/25: CT-scan of chest, abdomen and pelvis: Redemonstrated focal sigmoid colonic wall thickening, compatible with the patient's primary tumor, with adjacent ill-defined soft tissue nodularity, suspicious for tumor extension beyond the bowel wall. Redemonstrated bilobar hepatic metastases. The largest lesion within hepatic segment 4A appears slightly decreased in size from prior. Redemonstrated hepatic hypodense liver masses, reference lesions as follows: 1.9 x 1.7 cm segment 4A lesion (2/89), previously 2.1 x 1.8 cm Other smaller bilobar lesions are not significantly changed, for example 0.9 cm segment IVb lesion (2/112) Others are stable. Peritoneum/mesentery/omentum: Increasing presacral stranding as above. No free air. 2.7 x 0.9 cm soft tissue deposit within the anterior mesorectal fascia (2/200), previously 2.5 x 0.8 cm when remeasured similarly. Similar punctate soft tissue nodularity within the left upper abdomen (2/125), decreased from [date removed]. Lymph nodes: 1.2 cm short axis portacaval lymph node (2/105), previously 1.3 cm. 0.7 severe porta hepatis node, previously 0.9 cm (2/104) There are are several small nonspecific mesorectal and superior rectal nodes, measuring up to 0.4 cm (2/80). Attention on follow-up. 5/13/25: CT-scan chest, abdomen and pelvis: Liver: Hypoenhancing bilobar hepatic metastases, a few examples listed below. Mass General Brigham Patient Gateway - Past Visit Details https://patientgateway.massgeneralbrigham.org/MyChart-PRD/app/visit... 6 of 8 [date removed], 3:18 PM * Segment 2/4 measuring 3.6 cm (301-109), was 2.7 cm * Segment 2 measuring 2.5 cm (301-166), was 1.6 cm * Segment 7/8 measuring 1.6 cm (301-158), was 1.0 cm * Segment 3 measuring 1.5 cm (301-80), was barely perceptible on prior * Segment 4 measuring 2.5 cm (301-197), was 1.4 cm Gastrointestinal Tract: Masslike wall thickening of the sigmoid colon with extension into the mesocolon, similar to minimally worse than prior exam given differences in bowel orientation. There is a left lower quadrant transverse loop colostomy 3.6 x 1.9 cm metastatic implant along the anterior peritoneal reflection was 3.3 x 1.3 cm on prior. Direct extension into the mesocolon from the primary sigmoid colonic tumor appears similar to slightly worse (for example series 301 image 274 and 279). Small ascites similar to slightly decreased from prior. There is peritoneal thickening/enhancement diffusely in the pelvis. Similar omental stranding in the upper abdomen (301-199) with slightly more conspicuous few small omental nodes or implants (301-207, 211, 225 and 226) which is concerning for peritoneal spread of disease A few small likely metastatic mesorectal nodes slightly more conspicuous than prior, for example a 0.9 cm node (301-293) was 0.5 cm on prior. A nonspecific 1.4 cm portacaval node is unchanged 710/25: CT-scan of chest, abdomen and pelvis Decreased liver lesions, including: 22 mm segment 4 (3 1:155) from 24 mm 16 mm segment 2 (301:157) from 23 mm 14 mm segment 4 (301:185) from 26 mm 9 mm segment 8 (301:150) from 11 mm No new or increased liver lesions. Spleen: Enlarged, 140 mm. No lesions. Bowel: Transverse loop colostomy. No obstruction. Normal appendix. Decreased sigmoid colon mass with tethering to adjacent small bowel (301:272). Peritoneum/retroperitoneum: Nearly resolved lower abdominal fluid with mild residual peritoneal thickening. Markedly decreased peritoneal implant at the rectovesical recess/peritoneal reflection, now 7 mm short axis (3 1:290) from 20 mm. Tethering of the sigmoid colon and seminal vesicles remains. No new or increased peritoneal disease. Lymph nodes: Resolves lower abdominal lymphadenopathy. Unchanged 15 mm portacaval node (3 1:180). 8/12/25: CT-scan of chest, abdomen and pelvis: Hepatic metastatic lesions are all either slightly decreased in size or unchanged. Unchanged appearance of primary sigmoid tumor and post-treatment changes. Redemonstrated peritoneal disease with no new nodular component seen. Slightly increased borderline mediastinal and hilar lymph nodes, likely reactive. Dependent opacity in the posterior RIGHT upper lobe along the RIGHT major fissure, most likely dependent atelectasis. Stable calcified and noncalcified lung nodules. 10/2/25: CT-scan of chest, abdomen and pelvis: Indeterminate small pulmonary nodules measuring up to 5 mm, unchanged since at least [date removed]. Borderline enlarged lymph nodes remain stable Since the prior CT from [date removed]: Continued improvement in hepatic metastases. Unchanged subtle peritoneal nodularity. Similar appearance of the Mass General Brigham Patient Gateway - Past Visit Details https://patientgateway.massgeneralbrigham.org/MyChart-PRD/app/visit... 7 of 8 [date removed], 3:18 PM MyChart® licensed from Epic Systems Corporation© 1999 - 2026 primary sigmoid lesion. Slightly increased nodularity in the pericolonic tissues, nonspecific, area represent transient changes related to coursing adjacent vessels, and attention to this area on follow-up to exclude worsening local disease. Increased prominence of mesenteric nodes though remaining subcentimeter short axis, indeterminate. 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