Preoperative radiotherapy in rectal signet-ring cell carcinoma – magnetic resonance imaging and treatment outcome

Figures & data

Figure 1. Tumor histology and MRI specimens – exemplified by Good-Responder #1 and Poor-Responder #2. (a) Diagnostic tumor biopsies, each in two magnifications, from rectum displaying SRCC differentiation. (b) Diagnostic MRI scans, axial and T2-weighted images, illustrating rectal tumors with SRCC signal pattern. (c) Preoperative MRI scans, axial and T2-weighted images, illustrating rectal tumors with SRCC signal pattern. (d) Surgical specimens, in several magnifications, depicting treatment responses.

Table I. Clinical patient characteristics

	Good-Responder #1	Good-Responder #2	Good-Responder #3	Poor-Responder #1	Poor-Responder #2	Poor-Responder #3
Sex,	male,	female,	male,	male,	male,	male,
Age (years)	66	75	65	52	68	65
Localsymptoms	pain,anal incontinence	rectal bleeding,mucous stools	perineal wound	rectal bleeding,mucous diarrhea	pain,rectal bleeding	pain,diarrhea
Weightloss	no	4 kg (<5%of body weight)	no	8 kg (˜10%of body weight)	no	10 kg (˜12%of body weight)
Comorbidity	insulin-dependent diabetes mellitus,rheumatoid arthritis	hypercholesterolemia	no	no	hypertension	hypertension

Table II. Findings on diagnostic MRI examinations

	Good-Responder #1	Good-Responder #2	Good-Responder #3	Poor-Responder #1	Poor-Responder #2	Poor-Responder #3
T-stage, Anatomical	T4a,tumor	T4a,tumor	–	T4a,tumor	T4a,tumor	T4a,tumor
tumor extension	infiltration beyond mesorectal compartment, into seminal vesicle	infiltration beyond mesorectal compartment, into posterior vaginal wall and levator ani and puborectal muscles	tumor infiltration into prostate, seminal vesicles, and levator ani muscle	infiltration throughout mesorectal compartment, including peritoneal reflection	infiltration beyond mesorectal compartment, into puborectal muscles	infiltration beyond mesorectal compartment, into seminal vesicles and pelvic sidewall
N-stage	N1	N1	–	N2	N2	N2
Extramuralvascular tumorinvasion	no	yes	–	yes	yes	yes
Extramesorectallymph nodedisease	no	no	on one pelvic sidewall and inguinal node	no	on both pelvic sidewalls and presacrally	on both pelvic sidewalls
Presence ofmiddle rectalarteries	no	no	–	yes	Yes	yes

Table III. Histopathology findings in surgical specimens

	Good-Responder #1	Good-Responder #2	Good-Responder #3	Poor-Responder #1	Poor-Responder #2	Poor-Responder #3
Staging	ypT0N0	ypT0N0	ypT0N0	ypT2N2	ypT2N2	ypT2N2
Resection margins	clear	clear	clear	circumferential margin with microscopic tumor cells	macroscopically involved	circumferential margin with microscopic tumor cells
Tumor morphology	acellular mucin pools throughout bowel wall and mesorectal compartment	acellular mucin pools throughout bowel wall and mesorectal compartment, extending into vaginal wall and anal muscles	acellular mucin pools diffusely infiltrating prostate, seminal vesicles, and anal muscles	SRCC throughout bowel wall and mesorectal compartment	SRCC, mucinous adenocarcinoma, and undifferentiated carcinoma throughout bowel wall, mesorectal compartment, and anal muscles	SRCC, mucinous adenocarcinoma, and occasional mucin pools and fibrosis throughout bowel wall, mesorectal compartment, and seminal vesicles
Mesorectal tumor deposits	no	no	–	abundant SRCC deposits, lymph node architecture destroyed	confluent tumor infiltrates, lymph node architecture destroyed	6 of 9 lymph nodes containing tumor cells and mucin
Extramural vascular tumor invasion	no	no (mesorectal vessels containing acellular mucin)	–	yes	yes	not specified
Extramesorectal lymph node disease	–	–	no (resected nodes containing acellular mucin pools)	no (resected nodes containing acellular mucin pools)	unknown (nodes not resected)	unknown (nodes not resected)